Patent Publication Number: US-7588127-B2

Title: Elevator rail joint detector and elevator system

Description:
TECHNICAL FIELD 
     The present invention relates to an elevator rail joint detecting device for detecting the presence/absence of a joint in a guide rail having a plurality of unit rails that are vertically connected to each other, and to an elevator apparatus employing the elevator rail joint detecting device. 
     BACKGROUND ART 
     JP 2002-226149 A discloses an elevator apparatus in which a vertically extending code rail is provided in a hoistway in order to detect the position of an elevator car. Markers are formed at intervals in the code rail. Further, a CCD camera for reading the markers is provided to the car. Information on the markers, which is read by the CCD camera, is inputted to a controller to thereby detect the position of the car. 
     Further, JP 9-124238 A discloses an elevator apparatus in which irregularities are formed in the surface of the guide rail for guiding a car in order to detect the position of the car. The irregularities are formed in the guide rail at a constant interval in the vertical direction. Further, the car is provided with an optical position detecting element for reading the irregularities. The position of the car is detected by measuring the period of the irregularities, which is read by the optical position detecting element. 
     In the elevator apparatus as described above, however, in order to detect the position of the car, it is necessary to provide the code rail within the hoistway or to form the irregularities in the guide rail. That is, to mount the car position detecting device to an elevator, it is necessary to perform a large-scale construction work on the entire elevator apparatus. 
     DISCLOSURE OF THE INVENTION 
     The present invention has been made with a view to solving the above-mentioned problem, and therefore it is an object of the present invention to provide an elevator rail joint detecting device that can be easily installed in an elevator and is capable of detecting a joint in a guide rail for the detection of the car position, and an elevator apparatus using the elevator rail joint detecting device. 
     An elevator rail joint detecting device according to the present invention includes: a joint detecting portion opposed to a guide rail, which has a plurality of unit rails vertically connected to each other, and provided to a car guided by the guide rail, for detecting the presence of a joint between each of the unit rails; and a joint determining portion for determining the presence/absence of the joint based on information from the joint detecting portion. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic diagram showing an elevator apparatus according to Embodiment 1 of the present invention. 
         FIG. 2  is a front view showing the safety device of  FIG. 1 . 
         FIG. 3  is a front view showing the safety device of  FIG. 2  that has been actuated. 
         FIG. 4  is a schematic diagram showing an elevator apparatus according to Embodiment 2 of the present invention. 
         FIG. 5  is a front view showing the safety device of  FIG. 4 . 
         FIG. 6  is a front view showing the safety device of  FIG. 5  that has been actuated. 
         FIG. 7  is a front view showing the drive portion of  FIG. 6 . 
         FIG. 8  is a schematic diagram showing an elevator apparatus according to Embodiment 3 of the present invention. 
         FIG. 9  is a schematic diagram showing an elevator apparatus according to Embodiment 4 of the present invention. 
         FIG. 10  is a schematic diagram showing an elevator apparatus according to Embodiment 5 of the present invention. 
         FIG. 11  is a schematic diagram showing an elevator apparatus according to Embodiment 6 of the present invention. 
         FIG. 12  is a schematic diagram showing another example of the elevator apparatus shown in  FIG. 11 . 
         FIG. 13  is a schematic diagram showing an elevator apparatus according to Embodiment 7 of the present invention. 
         FIG. 14  is a schematic diagram showing an elevator apparatus according to Embodiment 8 of the present invention. 
         FIG. 15  is a front view showing another example of the drive portion shown in  FIG. 7 . 
         FIG. 16  is a plan view showing a safety device according to Embodiment 9 of the present invention. 
         FIG. 17  is a partially cutaway side view showing a safety device according to Embodiment 10 of the present invention. 
         FIG. 18  is a schematic diagram showing an elevator apparatus according to Embodiment 11 of the present invention. 
         FIG. 19  is a graph showing the car speed abnormality determination criteria stored in the memory portion of  FIG. 18 . 
         FIG. 20  is a graph showing the car acceleration abnormality determination criteria stored in the memory portion of  FIG. 18 . 
         FIG. 21  is a schematic diagram showing an elevator apparatus according to Embodiment 12 of the present invention. 
         FIG. 22  is a schematic diagram showing an elevator apparatus according to Embodiment 13 of the present invention. 
         FIG. 23  is a diagram showing the rope fastening device and the rope sensors of  FIG. 22 . 
         FIG. 24  is a diagram showing a state where one of the main ropes of  FIG. 23  has broken. 
         FIG. 25  is a schematic diagram showing an elevator apparatus according to Embodiment 14 of the present invention. 
         FIG. 26  is a schematic diagram showing an elevator apparatus according to Embodiment 15 of the present invention. 
         FIG. 27  is a perspective view of the car and the door sensor of  FIG. 26 . 
         FIG. 28  is a perspective view showing a state in which the car entrance  26  of  FIG. 27  is open. 
         FIG. 29  is a schematic diagram showing an elevator apparatus according to Embodiment 16 of the present invention. 
         FIG. 30  is a diagram showing an upper portion of the hoistway of  FIG. 29 . 
         FIG. 31  is a schematic diagram showing an elevator apparatus according to Embodiment 17 of the present invention. 
         FIG. 32  is a schematic diagram showing the rail joint detecting device of  FIG. 31 . 
         FIG. 33  is a schematic diagram showing an elevator rail joint detecting device according to Embodiment 18 of the present invention. 
         FIG. 34  is a schematic diagram showing an elevator rail joint detecting device according to Embodiment 19 of the present invention. 
         FIG. 35  is a schematic diagram showing an elevator rail joint detecting device according to Embodiment 20 of the present invention. 
     
    
    
     BEST MODE FOR CARRYING OUT THE INVENTION 
     Hereinbelow, preferred embodiments of the present invention are described with reference to the drawings. 
     Embodiment 1 
       FIG. 1  is a schematic diagram showing an elevator apparatus according to Embodiment 1 of the present invention. Referring to  FIG. 1 , a pair of car guide rails  2  are arranged within a hoistway  1 . A car  3  is guided by the car guide rails  2  as it is raised and lowered in the hoistway  1 . Arranged at the upper end portion of the hoistway  1  is a hoisting machine (not shown) for raising and lowering the car  3  and a counterweight (not shown). A main rope  4  is wound around a drive sheave of the hoisting machine. The car  3  and the counterweight are suspended in the hoistway  1  by means of the main rope  4 . Mounted to the car  3  are a pair of safety devices  5  opposed to the respective guide rails  2  and serving as braking means. The safety devices  5  are arranged on the underside of the car  3 . Braking is applied to the car  3  upon actuating the safety devices  5 . 
     Also arranged at the upper end portion of the hoistway  1  is a governor  6  serving as a car speed detecting means for detecting the ascending/descending speed of the car  3 . The governor  6  has a governor main body  7  and a governor sheave  8  rotatable with respect to the governor main body  7 . A rotatable tension pulley  9  is arranged at a lower end portion of the hoistway  1 . Wound between the governor sheave  8  and the tension pulley  9  is a governor rope  10  connected to the car  3 . The connecting portion between the governor rope  10  and the car  3  undergoes vertical reciprocating motion as the car  3  travels. As a result, the governor sheave  8  and the tension pulley  9  are rotated at a speed corresponding to the ascending/descending speed of the car  3 . 
     The governor  6  is adapted to actuate a braking device of the hoisting machine when the ascending/descending speed of the car  3  has reached a preset first overspeed. Further, the governor  6  is provided with a switch portion  11  serving as an output portion through which an actuation signal is output to the safety devices  5  when the descending speed of the car  3  reaches a second overspeed (set overspeed) higher than the first overspeed. The switch portion  11  has a contact  16  which is mechanically opened and closed by means of an overspeed lever that is displaced according to the centrifugal force of the rotating governor sheave  8 . The contact  16  is electrically connected to a battery  12 , which is an uninterruptible power supply capable of feeding power even in the event of a power failure, and to a control panel  13  that controls the drive of an elevator, through a power supply cable  14  and a connection cable  15 , respectively. 
     A control cable (movable cable) is connected between the car  3  and the control panel  13 . The control cable includes, in addition to multiple power lines and signal lines, an emergency stop wiring  17  electrically connected between the control panel  13  and each safety device  5 . By closing of the contact  16 , power from the battery  12  is supplied to each safety device  5  by way of the power supply cable  14 , the switch portion  11 , the connection cable  15 , a power supply circuit within the control panel  13 , and the emergency stop wiring  17 . It should be noted that transmission means consists of the connection cable  15 , the power supply circuit within the control panel  13 , and the emergency stop wiring  17 . 
       FIG. 2  is a front view showing the safety device  5  of  FIG. 1 , and  FIG. 3  is a front view showing the safety device  5  of  FIG. 2  that has been actuated. Referring to the figures, a support member  18  is fixed in position below the car  3 . The safety device  5  is fixed to the support member  18 . Further, each safety device  5  includes a pair of actuator portions  20 , which are connected to a pair of wedges  19  serving as braking members and capable of moving into and away from contact with the car guide rail  2  to displace the wedges  19  with respect to the car  3 , and a pair of guide portions  21  which are fixed to the support member  18  and guide the wedges  19  displaced by the actuator portions  20  into contact with the car guide rail  2 . The pair of wedges  19 , the pair of actuator portions  20 , and the pair of guide portions  21  are each arranged symmetrically on both sides of the car guide rail  2 . 
     Each guide portion  21  has an inclined surface  22  inclined with respect to the car guide rail  2  such that the distance between it and the car guide rail  2  decreases with increasing proximity to its upper portion. The wedge  19  is displaced along the inclined surface  22 . Each actuator portion  20  includes a spring  23  serving as an urging portion that urges the wedge  19  upward toward the guide portion  21  side, and an electromagnet  24  which, when supplied with electric current, generates an electromagnetic force for displacing the wedge  19  downward away from the guide member  21  against the urging force of the spring  23 . 
     The spring  23  is connected between the support member  18  and the wedge  19 . The electromagnet  24  is fixed to the support member  18 . The emergency stop wiring  17  is connected to the electromagnet  24 . Fixed to each wedge  19  is a permanent magnet  25  opposed to the electromagnet  24 . The supply of electric current to the electromagnet  24  is performed from the battery  12  (see  FIG. 1 ) by the closing of the contact  16  (see  FIG. 1 ). The safety device  5  is actuated as the supply of electric current to the electromagnet  24  is cut off by the opening of the contact  16  (see  FIG. 1 ). That is, the pair of wedges  19  are displaced upward due to the elastic restoring force of the spring  23  to be pressed against the car guide rail  2 . 
     Next, operation is described. The contact  16  remains closed during normal operation. Accordingly, power is supplied from the battery  12  to the electromagnet  24 . The wedge  19  is attracted and held onto the electromagnet  24  by the electromagnetic force generated upon this power supply, and thus remains separated from the car guide rail  2  ( FIG. 2 ). 
     When, for instance, the speed of the car  3  rises to reach the first overspeed due to a break in the main rope  4  or the like, this actuates the braking device of the hoisting machine. When the speed of the car  3  rises further even after the actuation of the braking device of the hoisting machine and reaches the second overspeed, this triggers closure of the contact  16 . As a result, the supply of electric current to the electromagnet  24  of each safety device  5  is cut off, and the wedges  19  are displaced by the urging force of the springs  23  upward with respect to the car  3 . At this time, the wedges  19  are displaced along the inclined surface  22  while in contact with the inclined surface  22  of the guide portions  21 . Due to this displacement, the wedges  19  are pressed into contact with the car guide rail  2 . The wedges  19  are displaced further upward as they come into contact with the car guide rail  2 , to become wedged in between the car guide rail  2  and the guide portions  21 . A large frictional force is thus generated between the car guide rail  2  and the wedges  19 , braking the car  3  ( FIG. 3 ). 
     To release the braking on the car  3 , the car  3  is raised while supplying electric current to the electromagnet  24  by the closing of the contact  16 . As a result, the wedges  19  are displaced downward, thus separating from the car guide rail  2 . 
     In the above-described elevator apparatus, the switch portion  11  connected to the battery  12  and each safety device  5  are electrically connected to each other, whereby an abnormality in the speed of the car  3  detected by the governor  6  can be transmitted as an electrical actuation signal from the switch portion  11  to each safety device  5 , making it possible to brake the car  3  in a short time after detecting an abnormality in the speed of the car  3 . As a result, the braking distance of the car  3  can be reduced. Further, synchronized actuation of the respective safety devices  5  can be readily effected, making it possible to stop the car  3  in a stable manner. Also, each safety device  5  is actuated by the electrical actuation signal, thus preventing the safety device  5  from being erroneously actuated due to shaking of the car  3  or the like. 
     Additionally, each safety device  5  has the actuator portions  20  which displace the wedge  19  upward toward the guide portion  21  side, and the guide portions  21  each including the inclined surface  22  to guide the upwardly displaced wedge  19  into contact with the car guide rail  2 , whereby the force with which the wedge  19  is pressed against the car guide rail  2  during descending movement of the car  3  can be increased with reliability. 
     Further, each actuator portion  20  has a spring  23  that urges the wedge  19  upward, and an electromagnet  24  for displacing the wedge  19  downward against the urging force of the spring  23 , thereby enabling displacement of the wedge  19  by means of a simple construction. 
     Embodiment 2 
       FIG. 4  is a schematic diagram showing an elevator apparatus according to Embodiment 2 of the present invention. Referring to  FIG. 4 , the car  3  has a car main body  27  provided with a car entrance  26 , and a car door  28  that opens and closes the car entrance  26 . Provided in the hoistway  1  is a car speed sensor  31  serving as car speed detecting means for detecting the speed of the car  3 . Mounted inside the control panel  13  is an output portion  32  electrically connected to the car speed sensor  31 . The battery  12  is connected to the output portion  32  through the power supply cable  14 . Electric power used for detecting the speed of the car  3  is supplied from the output portion  32  to the car speed sensor  31 . The output portion  32  is input with a speed detection signal from the car speed sensor  31 . 
     Mounted on the underside of the car  3  are a pair of safety devices  33  serving as braking means for braking the car  3 . The output portion  32  and each safety device  33  are electrically connected to each other through the emergency stop wiring  17 . When the speed of the car  3  is at the second overspeed, an actuation signal, which is the actuating power, is output to each safety device  33 . The safety devices  33  are actuated upon input of this actuation signal. 
       FIG. 5  is a front view showing the safety device  33  of  FIG. 4 , and  FIG. 6  is a front view showing the safety device  33  of  FIG. 5  that has been actuated. Referring to the figures, the safety device  33  has a wedge  34  serving as a braking member and capable of moving into and away from contact with the car guide rail  2 , an actuator portion  35  connected to a lower portion of the wedge  34 , and a guide portion  36  arranged above the wedge  34  and fixed to the car  3 . The wedge  34  and the actuator portion  35  are capable of vertical movement with respect to the guide portion  36 . As the wedge  34  is displaced upward with respect to the guide portion  36 , that is, toward the guide portion  36  side, the wedge  34  is guided by the guide portion  36  into contact with the car guide rail  2 . 
     The actuator portion  35  has a cylindrical contact portion  37  capable of moving into and away from contact with the car guide rail  2 , an actuating mechanism  38  for displacing the contact portion  37  into and away from contact with the car guide rail  2 , and a support portion  39  supporting the contact portion  37  and the actuating mechanism  38 . The contact portion  37  is lighter than the wedge  34  so that it can be readily displaced by the actuating mechanism  38 . The actuating mechanism  38  has a movable portion  40  capable of reciprocating displacement between a contact position where the contact portion  37  is held in contact with the car guide rail  2  and a separated position where the contact portion  37  is separated from the car guide rail  2 , and a drive portion  41  for displacing the movable portion  40 . 
     The support portion  39  and the movable portion  40  are provided with a support guide hole  42  and a movable guide hole  43 , respectively. The inclination angles of the support guide hole  42  and the movable guide hole  43  with respect to the car guide rail  2  are different from each other. The contact portion  37  is slidably fitted in the support guide hole  42  and the movable guide hole  43 . The contact portion  37  slides within the movable guide hole  43  according to the reciprocating displacement of the movable portion  40 , and is displaced along the longitudinal direction of the support guide hole  42 . As a result, the contact portion  37  is moved into and away from contact with the car guide rail  2  at an appropriate angle. When the contact portion  37  comes into contact with the car guide rail  2  as the car  3  descends, braking is applied to the wedge  34  and the actuator portion  35 , displacing them toward the guide portion  36  side. 
     Mounted on the upperside of the support portion  39  is a horizontal guide hole  47  extending in the horizontal direction. The wedge  34  is slidably fitted in the horizontal guide hole  47 . That is, the wedge  34  is capable of reciprocating displacement in the horizontal direction with respect to the support portion  39 . 
     The guide portion  36  has an inclined surface  44  and a contact surface  45  which are arranged so as to sandwich the car guide rail  2  therebetween. The inclined surface  44  is inclined with respect to the car guide rail  2  such that the distance between it and the car guide rail  2  decreases with increasing proximity to its upper portion. The contact surface  45  is capable of moving into and away from contact with the car guide rail  2 . As the wedge  34  and the actuator portion  35  are displaced upward with respect to the guide portion  36 , the wedge  34  is displaced along the inclined surface  44 . As a result, the wedge  34  and the contact surface  45  are displaced so as to approach each other, and the car guide rail  2  becomes lodged between the wedge  34  and the contact surface  45 . 
       FIG. 7  is a front view showing the drive portion  41  of  FIG. 6 . Referring to  FIG. 7 , the drive portion  41  has a disc spring  46  serving as an urging portion and attached to the movable portion  40 , and an electromagnet  48  for displacing the movable portion  40  by an electromagnetic force generated upon supply of electric current thereto. 
     The movable portion  40  is fixed to the central portion of the disc spring  46 . The disc spring  46  is deformed due to the reciprocating displacement of the movable portion  40 . As the disc spring  46  is deformed due to the displacement of the movable portion  40 , the urging direction of the disc spring  46  is reversed between the contact position (solid line) and the separated position (broken line). The movable portion  40  is retained at the contact or separated position as it is urged by the disc spring  46 . That is, the contact or separated state of the contact portion  37  with respect to the car guide rail  2  is retained by the urging of the disc spring  46 . 
     The electromagnet  48  has a first electromagnetic portion  49  fixed to the movable portion  40 , and a second electromagnetic portion  50  opposed to the first electromagnetic portion  49 . The movable portion  40  is displaceable relative to the second electromagnetic portion  50 . The emergency stop wiring  17  is connected to the electromagnet  48 . Upon inputting an actuation signal to the electromagnet  48 , the first electromagnetic portion  49  and the second electromagnetic portion  50  generate electromagnetic forces so as to repel each other. That is, upon input of the actuation signal to the electromagnet  48 , the first electromagnetic portion  49  is displaced away from contact with the second electromagnetic portion  50 , together with the movable portion  40 . 
     It should be noted that for recovery after the actuation of the safety device  5 , the output portion  32  outputs a recovery signal during the recovery phase. Input of the recovery signal to the electromagnet  48  causes the first electromagnetic portion  49  and the second electromagnetic portion  50  to attract each other. Otherwise, this embodiment is of the same construction as Embodiment 1. 
     Next, operation is described. During normal operation, the movable portion  40  is located at the separated position, and the contact portion  37  is urged by the disc spring  46  to be separated away from contact with the car guide rail  2 . With the contact portion  37  thus being separated from the car guide rail  2 , the wedge  34  is separated from the guide portion  36 , thus maintaining the distance between the wedge  34  and the guide portion  36 . 
     When the speed detected by the car speed sensor  31  reaches the first overspeed, this actuates the braking device of the hoisting machine. When the speed of the car  3  continues to rise thereafter and the speed as detected by the car speed sensor  31  reaches the second overspeed, an actuation signal is output from the output portion  32  to each safety device  33 . Inputting this actuation signal to the electromagnet  48  triggers the first electromagnetic portion  49  and the second electromagnetic portion  50  to repel each other. The electromagnetic repulsion force thus generated causes the movable portion  40  to be displaced into the contact position. As this happens, the contact portion  37  is displaced into contact with the car guide rail  2 . By the time the movable portion  40  reaches the contact position, the urging direction of the disc spring  46  reverses to that for retaining the movable portion  40  at the contact position. As a result, the contact portion  37  is pressed into contact with the car guide rail  2 , thus braking the wedge  34  and the actuator portion  35 . 
     Since the car  3  and the guide portion  36  descend with no braking applied thereon, the guide portion  36  is displaced downward towards the wedge  34  and actuator  35  side. Due to this displacement, the wedge  34  is guided along the inclined surface  44 , causing the car guide rail  2  to become lodged between the wedge  34  and the contact surface  45 . As the wedge  34  comes into contact with the car guide rail  2 , it is displaced further upward to wedge in between the car guide rail  2  and the inclined surface  44 . A large frictional force is thus generated between the car guide rail  2  and the wedge  34 , and between the car guide rail  2  and the contact surface  45 , thus braking the car  3 . 
     During the recovery phase, the recovery signal is transmitted from the output portion  32  to the electromagnet  48 . This causes the first electromagnetic portion  49  and the second electromagnetic portion  50  to attract each other, thus displacing the movable portion  40  to the separated position. As this happens, the contact portion  37  is displaced to be separated away from contact with the car guide rail  2 . By the time the movable portion  40  reaches the separated position, the urging direction of the disc spring  46  reverses, allowing the movable portion  40  to be retained at the separated position. As the car  3  ascends in this state, the pressing contact of the wedge  34  and the contact surface  45  with the car guide rail  2  is released. 
     In addition to providing the same effects as those of Embodiment 1, the above-described elevator apparatus includes the car speed sensor  31  provided in the hoistway  1  to detect the speed of the car  3 . There is thereby no need to use a speed governor and a governor rope, making it possible to reduce the overall installation space for the elevator apparatus. 
     Further, the actuator portion  35  has the contact portion  37  capable of moving into and away from contact with the car guide rail  2 , and the actuating mechanism  38  for displacing the contact portion  37  into and away from contact with the car guide rail  2 . Accordingly, by making the weight of the contact portion  37  smaller than that of the wedge  34 , the drive force to be applied from the actuating mechanism  38  to the contact portion  37  can be reduced, thus making it possible to miniaturize the actuating mechanism  38 . Further, the lightweight construction of the contact portion  37  allows increases in the displacement rate of the contact portion  37 , thereby reducing the time required until generation of a braking force. 
     Further, the drive portion  41  includes the disc spring  46  adapted to hold the movable portion  40  at the contact position or the separated position, and the electromagnet  48  capable of displacing the movable portion  40  when supplied with electric current, whereby the movable portion  40  can be reliably held at the contact or separated position by supplying electric current to the electromagnet  48  only during the displacement of the movable portion  40 . 
     Embodiment 3 
       FIG. 8  is a schematic diagram showing an elevator apparatus according to Embodiment 3 of the present invention. Referring to  FIG. 8 , provided at the car entrance  26  is a door closed sensor  58 , which serves as a door closed detecting means for detecting the open or closed state of the car door  28 . An output portion  59  mounted on the control panel  13  is connected to the door closed sensor  58  through a control cable. Further, the car speed sensor  31  is electrically connected to the output portion  59 . A speed detection signal from the car speed sensor  31  and an open/closed detection signal from the door closed sensor  58  are input to the output portion  59 . On the basis of the speed detection signal and the open/closed detection signal thus input, the output portion  59  can determine the speed of the car  3  and the open or closed state of the car entrance  26 . 
     The output portion  59  is connected to each safety device  33  through the emergency stop wiring  17 . On the basis of the speed detection signal from the car speed sensor  31  and the opening/closing detection signal from the door closed sensor  58 , the output portion  59  outputs an actuation signal when the car  3  has descended with the car entrance  26  being open. The actuation signal is transmitted to the safety device  33  through the emergency stop wiring  17 . Otherwise, this embodiment is of the same construction as Embodiment 2. 
     In the elevator apparatus as described above, the car speed sensor  31  that detects the speed of the car  3 , and the door closed sensor  58  that detects the open or closed state of the car door  28  are electrically connected to the output portion  59 , and the actuation signal is output from the output portion  59  to the safety device  33  when the car  3  has descended with the car entrance  26  being open, thereby preventing the car  3  from descending with the car entrance  26  being open. 
     It should be noted that safety devices vertically reversed from the safety devices  33  may be mounted to the car  3 . This construction also makes it possible to prevent the car  3  from ascending with the car entrance  26  being open. 
     Embodiment 4 
       FIG. 9  is a schematic diagram showing an elevator apparatus according to Embodiment 4 of the present invention. Referring to  FIG. 9 , passed through the main rope  4  is a break detection lead wire  61  serving as a rope break detecting means for detecting a break in the rope  4 . A weak current flows through the break detection lead wire  61 . The presence of a break in the main rope  4  is detected on the basis of the presence or absence of this weak electric current passing therethrough. An output portion  62  mounted on the control panel  13  is electrically connected to the break detection lead wire  61 . When the break detection lead wire  61  breaks, a rope break signal, which is an electric current cut-off signal of the break detection lead wire  61 , is input to the output portion  62 . The car speed sensor  31  is also electrically connected to the output portion  62 . 
     The output portion  62  is connected to each safety device  33  through the emergency stop wiring  17 . If the main rope  4  breaks, the output portion  62  outputs an actuation signal on the basis of the speed detection signal from the car speed sensor  31  and the rope break signal from the break detection lead wire  61 . The actuation signal is transmitted to the safety device  33  through the emergency stop wiring  17 . Otherwise, this embodiment is of the same construction as Embodiment 2. 
     In the elevator apparatus as described above, the car speed sensor  31  which detects the speed of the car  3  and the break detection lead wire  61  which detects a break in the main rope  4  are electrically connected to the output portion  62 , and, when the main rope  4  breaks, the actuation signal is output from the output portion  62  to the safety device  33 . By thus detecting the speed of the car  3  and detecting a break in the main rope  4 , braking can be more reliably applied to a car  3  that is descending at abnormal speed. 
     While in the above example the method of detecting the presence or absence of an electric current passing through the break detection lead wire  61 , which is passed through the main rope  4 , is employed as the rope break detecting means, it is also possible to employ a method of, for example, measuring changes in the tension of the main rope  4 . In this case, a tension measuring instrument is installed on the rope fastening. 
     Embodiment 5 
       FIG. 10  is a schematic diagram showing an elevator apparatus according to Embodiment 5 of the present invention. Referring to  FIG. 10 , provided in the hoistway  1  is a car position sensor  65  serving as car position detecting means for detecting the position of the car  3 . The car position sensor  65  and the car speed sensor  31  are electrically connected to an output portion  66  mounted on the control panel  13 . The output portion  66  has a memory portion  67  storing a control pattern containing information on the position, speed, acceleration/deceleration, floor stops, etc., of the car  3  during normal operation. Inputs to the output portion  66  are a speed detection signal from the car speed sensor  31  and a car position signal from the car position sensor  65 . 
     The output portion  66  is connected to the safety device  33  through the emergency stop wiring  17 . The output portion  66  compares the speed and position (actual measured values) of the car  3  based on the speed detection signal and the car position signal with the speed and position (set values) of the car  3  based on the control pattern stored in the memory portion  67 . The output portion  66  outputs an actuation signal to the safety device  33  when the deviation between the actual measured values and the set values exceeds a predetermined threshold. Herein, the predetermined threshold refers to the minimum deviation between the actual measurement values and the set values required for bringing the car  3  to a halt through normal braking without the car  3  colliding against an end portion of the hoistway  1 . Otherwise, this embodiment is of the same construction as Embodiment 2. 
     In the elevator apparatus as described above, the output portion  66  outputs the actuation signal when the deviation between the actual measurement values from each of the car speed sensor  31  and the car position sensor  65  and the set values based on the control pattern exceeds the predetermined threshold, making it possible to prevent collision of the car  3  against the end portion of the hoistway  1 . 
     Embodiment 6 
       FIG. 11  is a schematic diagram showing an elevator apparatus according to Embodiment 6 of the present invention. Referring to  FIG. 11 , arranged within the hoistway  1  are an upper car  71  that is a first car and a lower car  72  that is a second car located below the upper car  71 . The upper car  71  and the lower car  72  are guided by the car guide rail  2  as they ascend and descend in the hoistway  1 . Installed at the upper end portion of the hoistway  1  are a first hoisting machine (not shown) for raising and lowering the upper car  71  and an upper-car counterweight (not shown), and a second hoisting machine (not shown) for raising and lowering the lower car  72  and a lower-car counterweight (not shown). A first main rope (not shown) is wound around the drive sheave of the first hoisting machine, and a second main rope (not shown) is wound around the drive sheave of the second hoisting machine. The upper car  71  and the upper-car counterweight are suspended by the first main rope, and the lower car  72  and the lower-car counterweight are suspended by the second main rope. 
     In the hoistway  1 , there are provided an upper-car speed sensor  73  and a lower-car speed sensor  74  respectively serving as car speed detecting means for detecting the speed of the upper car  71  and the speed of the lower car  72 . Also provided in the hoistway  1  are an upper-car position sensor  75  and a lower-car position sensor  76  respectively serving as car position detecting means for detecting the position of the upper car  71  and the position of the lower car  72 . 
     It should be noted that car operation detecting means includes the upper-car speed sensor  73 , the lower-car sped sensor  74 , the upper-car position sensor  75 , and the lower-car position sensor  76 . 
     Mounted on the underside of the upper car  71  are upper-car safety devices  77  serving as braking means of the same construction as that of the safety devices  33  used in Embodiment 2. Mounted on the underside of the lower car  72  are lower-car safety devices  78  serving as braking means of the same construction as that of the upper-car safety devices  77 . 
     An output portion  79  is mounted inside the control panel  13 . The upper-car speed sensor  73 , the lower-car speed sensor  74 , the upper-car position sensor  75 , and the lower-car position sensor  76  are electrically connected to the output portion  79 . Further, the battery  12  is connected to the output portion  79  through the power supply cable  14 . An upper-car speed detection signal from the upper-car speed sensor  73 , a lower-car speed detection signal from the lower-car speed sensor  74 , an upper-car position detecting signal from the upper-car position sensor  75 , and a lower-car position detection signal from the lower-car position sensor  76  are input to the output portion  79 . That is, information from the car operation detecting means is input to the output portion  79 . 
     The output portion  79  is connected to the upper-car safety device  77  and the lower-car safety device  78  through the emergency stop wiring  17 . Further, on the basis of the information from the car operation detecting means, the output portion  79  predicts whether or not the upper car  71  or the lower car  72  will collide against an end portion of the hoistway  1  and whether or not collision will occur between the upper car  71  and the lower car  72 ; when it is predicted that such collision will occur, the output portion  79  outputs an actuation signal to each the upper-car safety devices  77  and the lower-car safety devices  78 . The upper-car safety devices  77  and the lower-car safety devices  78  are each actuated upon input of this actuation signal. 
     It should be noted that a monitoring portion includes the car operation detecting means and the output portion  79 . The running states of the upper car  71  and the lower car  72  are monitored by the monitoring portion. Otherwise, this embodiment is of the same construction as Embodiment 2. 
     Next, operation is described. When input with the information from the car operation detecting means, the output portion  79  predicts whether or not the upper car  71  and the lower car  72  will collide against an end portion of the hoistway  1  and whether or not collision between the upper car and the lower car  72  will occur. For example, when the output portion  79  predicts that collision will occur between the upper car  71  and the lower car  72  due to a break in the first main rope suspending the upper car  71 , the output portion  79  outputs an actuation signal to each the upper-car safety devices  77  and the lower-car safety devices  78 . The upper-car safety devices  77  and the lower-car safety devices  78  are thus actuated, braking the upper car  71  and the lower car  72 . 
     In the elevator apparatus as described above, the monitoring portion has the car operation detecting means for detecting the actual movements of the upper car  71  and the lower car  72  as they ascend and descend in the same hoistway  1 , and the output portion  79  which predicts whether or not collision will occur between the upper car  71  and the lower car  72  on the basis of the information from the car operation detecting means and, when it is predicted that the collision will occur, outputs the actuation signal to each of the upper-car safety devices  77  and the lower-car emergency devices  78 . Accordingly, even when the respective speeds of the upper car  71  and the lower car  72  have not reached the set overspeed, the upper-car safety devices  77  and the lower-car emergency devices  78  can be actuated when it is predicted that collision will occur between the upper car  71  and the lower car  72 , thereby making it possible to avoid a collision between the upper car  71  and the lower car  72 . 
     Further, the car operation detecting means has the upper-car speed sensor  73 , the lower-car speed sensor  74 , the upper-car position sensor  75 , and the lower-car position sensor  76 , the actual movements of the upper car  71  and the lower car  72  can be readily detected by means of a simple construction. 
     While in the above-described example the output portion  79  is mounted inside the control panel  13 , an output portion  79  may be mounted on each of the upper car  71  and the lower car  72 . In this case, as shown in  FIG. 12 , the upper-car speed sensor  73 , the lower-car speed sensor  74 , the upper-car position sensor  75 , and the lower-car position sensor  76  are electrically connected to each of the output portions  79  mounted on the upper car  71  and the lower car  72 . 
     While in the above-described example the output portions  79  outputs the actuation signal to each the upper-car safety devices  77  and the lower-car safety devices  78 , the output portion  79  may, in accordance with the information from the car operation detecting means, output the actuation signal to only one of the upper-car safety device  77  and the lower-car safety device  78 . In this case, in addition to predicting whether or not collision will occur between the upper car  71  and the lower car  72 , the output portions  79  also determine the presence of an abnormality in the respective movements of the upper car  71  and the lower car  72 . The actuation signal is output from an output portion  79  to only the safety device mounted on the car which is moving abnormally. 
     Embodiment 7 
       FIG. 13  is a schematic diagram showing an elevator apparatus according to Embodiment 7 of the present invention. Referring to  FIG. 13 , an upper-car output portion  81  serving as an output portion is mounted on the upper car  71 , and a lower-car output portion  82  serving as an output portion is mounted on the lower car  72 . The upper-car speed sensor  73 , the upper-car position sensor  75 , and the lower-car position sensor  76  are electrically connected to the upper-car output portion  81 . The lower-car speed sensor  74 , the lower-car position sensor  76 , and the upper-car position sensor  75  are electrically connected to the lower-car output portion  82 . 
     The upper-car output portion  81  is electrically connected to the upper-car safety devices  77  through an upper-car emergency stop wiring  83  serving as transmission means installed on the upper car  71 . Further, the upper-car output portion  81  predicts, on the basis of information (hereinafter referred to as “upper-car detection information” in this embodiment) from the upper-car speed sensor  73 , the upper-car position sensor  75 , and the lower-car position sensor  76 , whether or not the upper car  71  will collide against the lower car  72 , and outputs an actuation signal to the upper-car safety devices  77  upon predicting that a collision will occur. Further, when input with the upper-car detection information, the upper-car output portion  81  predicts whether or not the upper car  71  will collide against the lower car  72  on the assumption that the lower car  72  is running toward the upper car  71  at its maximum normal operation speed. 
     The lower-car output portion  82  is electrically connected to the lower-car safety devices  78  through a lower-car emergency stop wiring  84  serving as transmission means installed on the lower car  72 . Further, the lower-car output portion  82  predicts, on the basis of information (hereinafter referred to as “lower-car detection information” in this embodiment) from the lower-car speed sensor  74 , the lower-car position sensor  76 , and the upper-car position sensor  75 , whether or not the lower car  72  will collide against the upper car  71 , and outputs an actuation signal to the lower-car safety devices  78  upon predicting that a collision will occur. Further, when input with the lower-car detection information, the lower-car output portion  82  predicts whether or not the lower car  72  will collide against the upper car  71  on the assumption that the upper car  71  is running toward the lower car  72  at its maximum normal operation speed. 
     Normally, the operations of the upper car  71  and the lower car  72  are controlled such that they are sufficiently spaced away from each other so that the upper-car safety devices  77  and the lower-car safety devices  78  do not actuate. Otherwise, this embodiment is of the same construction as Embodiment 6. 
     Next, operation is described. For instance, when, due to a break in the first main rope suspending the upper car  71 , the upper car  71  falls toward the lower car  72 , the upper-car output portion  81  and the lower-car output portion  82  both predict the impending collision between the upper car  71  and the lower car  72 . As a result, the upper-car output portion  81  and the lower-car output portion  82  each output an actuation signal to the upper-car safety devices  77  and the lower-car safety devices  78 , respectively. This actuates the upper-car safety devices  77  and the lower-car safety devices  78 , thus braking the upper car  71  and the lower car  72 . 
     In addition to providing the same effects as those of Embodiment 6, the above-described elevator apparatus, in which the upper-car speed sensor  73  is electrically connected to only the upper-car output portion  81  and the lower-car speed sensor  74  is electrically connected to only the lower-car output portion  82 , obviates the need to provide electrical wiring between the upper-car speed sensor  73  and the lower-car output portion  82  and between the lower-car speed sensor  74  and the upper-car output portion  81 , making it possible to simplify the electrical wiring installation. 
     Embodiment 8 
       FIG. 14  is a schematic diagram showing an elevator apparatus according to Embodiment 8 of the present invention. Referring to  FIG. 14 , mounted to the upper car  71  and the lower car  72  is an inter-car distance sensor  91  serving as inter-car distance detecting means for detecting the distance between the upper car  71  and the lower car  72 . The inter-car distance sensor  91  includes a laser irradiation portion mounted on the upper car  71  and a reflection portion mounted on the lower car  72 . The distance between the upper car  71  and the lower car  72  is obtained by the inter-car distance sensor  91  based on the reciprocation time of laser light between the laser irradiation portion and the reflection portion. 
     The upper-car speed sensor  73 , the lower-car speed sensor  74 , the upper-car position sensor  75 , and the inter-car distance sensor  91  are electrically connected to the upper-car output portion  81 . The upper-car speed sensor  73 , the lower-car speed sensor  74 , the lower-car position sensor  76 , and the inter-car distance sensor  91  are electrically connected to the lower-car output portion  82 . 
     The upper-car output portion  81  predicts, on the basis of information (hereinafter referred to as “upper-car detection information” in this embodiment) from the upper-car speed sensor  73 , the lower-car speed sensor  74 , the upper-car position sensor  75 , and the inter-car distance sensor  91 , whether or not the upper car  71  will collide against the lower car  72 , and outputs an actuation signal to the upper-car safety devices  77  upon predicting that a collision will occur. 
     The lower-car output portion  82  predicts, on the basis of information (hereinafter referred to as “lower-car detection information” in this embodiment) from the upper-car speed sensor  73 , the lower-car speed sensor  74 , the lower-car position sensor  76 , and the inter-car distance sensor  91 , whether or not the lower car  72  will collide against the upper car  71 , and outputs an actuation signal to the lower-car safety device  78  upon predicting that a collision will occur. Otherwise, this embodiment is of the same construction as Embodiment 7. 
     In the elevator apparatus as described above, the output portion  79  predicts whether or not a collision will occur between the upper car  71  and the lower car  72  based on the information from the inter-car distance sensor  91 , making it possible to predict with improved reliability whether or not a collision will occur between the upper car  71  and the lower car  72 . 
     It should be noted that the door closed sensor  58  of Embodiment 3 may be applied to the elevator apparatus as described in Embodiments 6 through 8 so that the output portion is input with the open/closed detection signal. It is also possible to apply the break detection lead wire  61  of Embodiment 4 here as well so that the output portion is input with the rope break signal. 
     While the drive portion in Embodiments 2 through 8 described above is driven by utilizing the electromagnetic repulsion force or the electromagnetic attraction force between the first electromagnetic portion  49  and the second electromagnetic portion  50 , the drive portion may be driven by utilizing, for example, an eddy current generated in a conductive repulsion plate. In this case, as shown in  FIG. 15 , a pulsed current is supplied as an actuation signal to the electromagnet  48 , and the movable portion  40  is displaced through the interaction between an eddy current generated in a repulsion plate  51  fixed to the movable portion  40  and the magnetic field from the electromagnet  48 . 
     While in Embodiments 2 through 8 described above the car speed detecting means is provided in the hoistway  1 , it may also be mounted on the car. In this case, the speed detection signal from the car speed detecting means is transmitted to the output portion through the control cable. 
     Embodiment 9 
       FIG. 16  is a plan view showing a safety device according to Embodiment 9 of the present invention. Here, a safety device  155  has the wedge  34 , an actuator portion  156  connected to a lower portion of the wedge  34 , and the guide portion  36  arranged above the wedge  34  and fixed to the car  3 . The actuator portion  156  is vertically movable with respect to the guide portion  36  together with the wedge  34 . 
     The actuator portion  156  has a pair of contact portions  157  capable of moving into and away from contact with the car guide rail  2 , a pair of link members  158   a ,  158   b  each connected to one of the contact portions  157 , an actuating mechanism  159  for displacing the link member  158   a  relative to the other link member  158   b  such that the respective contact portions  157  move into and away from contact with the car guide rail  2 , and a support portion  160  supporting the contact portions  157 , the link members  158   a ,  158   b , and the actuating mechanism  159 . A horizontal shaft  170 , which passes through the wedge  34 , is fixed to the support portion  160 . The wedge  34  is capable of reciprocating displacement in the horizontal direction with respect to the horizontal shaft  170 . 
     The link members  158   a ,  158   b  cross each other at a portion between one end to the other end portion thereof. Further, provided to the support portion  160  is a connection member  161  which pivotably connects the link member  158   a ,  158   b  together at the portion where the link members  158   a ,  158   b  cross each other. Further, the link member  158   a  is provided so as to be pivotable with respect to the other link member  158   b  about the connection member  161 . 
     As the respective other end portions of the link member  158   a ,  158   b  are displaced so as to approach each other, each contact portion  157  is displaced into contact with the car guide rail  2 . Likewise, as the respective other end portions of the link member  158   a ,  158   b  are displaced so as to separate away from each other, each contact portion  157  is displaced away from the car guide rail  2 . 
     The actuating mechanism  159  is arranged between the respective other end portions of the link members  158   a ,  158   b . Further, the actuating mechanism  159  is supported by each of the link members  158   a ,  158   b . Further, the actuating mechanism  159  includes a rod-like movable portion  162  connected to the link member  158   a , and a drive portion  163  fixed to the other link member  158   b  and adapted to displace the movable portion  162  in a reciprocating manner. The actuating mechanism  159  is pivotable about the connection member  161  together with the link members  158   a ,  158   b.    
     The movable portion  162  has a movable iron core  164  accommodated within the drive portion  163 , and a connecting rod  165  connecting the movable iron core  164  and the link member  158   b  to each other. Further, the movable portion  162  is capable of reciprocating displacement between a contact position where the contact portions  157  come into contact with the car guide rail  2  and a separated position where the contact portions  157  are separated away from contact with the car guide rail  2 . 
     The drive portion  163  has a stationary iron core  166  including a pair of regulating portions  166   a  and  166   b  regulating the displacement of the movable iron core  164  and a side wall portion  166   c  that connects the regulating members  166   a ,  166   b  to each other and, surrounding the movable iron core  164 , a first coil  167  which is accommodated within the stationary iron core  166  and which, when supplied with electric current, causes the movable iron core  164  to be displaced into contact with the regulating portion  166   a , a second coil  168  which is accommodated within the stationary iron core  166  and which, when supplied with electric current, causes the movable iron core  164  to be displaced into contact with the other regulating portion  166   b , and an annular permanent magnet  169  arranged between the first coil  167  and the second coil  168 . 
     The regulating member  166   a  is so arranged that the movable iron core  164  abuts on the regulating member  166   a  when the movable portion  162  is at the separated position. Further, the other regulating member  166   b  is so arranged that the movable iron core  164  abuts on the regulating member  166   b  when the movable portion  162  is at the contact position. 
     The first coil  167  and the second coil  168  are annular electromagnets that surround the movable portion  162 . Further, the first coil  167  is arranged between the permanent magnet  169  and the regulating portion  166   a , and the second coil  168  is arranged between the permanent magnet  169  and the other regulating portion  166   b.    
     With the movable iron core  164  abutting on the regulating portion  166   a , a space serving as a magnetic resistance exists between the movable iron core  164  and the other regulating member  166   b , with the result that the amount of magnetic flux generated by the permanent magnet  169  becomes larger on the first coil  167  side than on the second coil  168  side. Thus, the movable iron core  164  is retained in position while still abutting on the regulating member  166   a.    
     Further, with the movable iron core  164  abutting on the other regulating portion  166   b , a space serving as a magnetic resistance exists between the movable iron core  164  and the regulating member  166   a , with the result that the amount of magnetic flux generated by the permanent magnet  169  becomes larger on the second coil  168  side than on the first coil  167  side. Thus, the movable iron core  164  is retained in position while still abutting on the other regulating member  166   b.    
     Electric power serving as an actuation signal from the output portion  32  can be input to the second coil  168 . When input with the actuation signal, the second coil  168  generates a magnetic flux acting against the force that keeps the movable iron core  164  in abutment with the regulating portion  166   a . Further, electric power serving as a recovery signal from the output portion  32  can be input to the first coil  167 . When input with the recovery signal, the first coil  167  generates a magnetic flux acting against the force that keeps the movable iron core  164  in abutment with the other regulating portion  166   b.    
     Otherwise, this embodiment is of the same construction as Embodiment 2. 
     Next, operation is described. During normal operation, the movable portion  162  is located at the separated position, with the movable iron core  164  being held in abutment on the regulating portion  166   a  by the holding force of the permanent magnet  169 . With the movable iron core  164  abutting on the regulating portion  166   a , the wedge  34  is maintained at a spacing from the guide portion  36  and separated away from the car guide rail  2 . 
     Thereafter, as in Embodiment 2, by outputting an actuation signal to each safety device  155  from the output portion  32 , electric current is supplied to the second coil  168 . This generates a magnetic flux around the second coil  168 , which causes the movable iron core  164  to be displaced toward the other regulating portion  166   b , that is, from the separated position to the contact position. As this happens, the contact portions  157  are displaced so as to approach each other, coming into contact with the car guide rail  2 . Braking is thus applied to the wedge  34  and the actuator portion  155 . 
     Thereafter, the guide portion  36  continues its descent, thus approaching the wedge  34  and the actuator portion  155 . As a result, the wedge  34  is guided along the inclined surface  44 , causing the car guide rail  2  to be held between the wedge  34  and the contact surface  45 . Thereafter, the car  3  is braked through operations identical to those of Embodiment 2. 
     During the recovery phase, a recovery signal is transmitted from the output portion  32  to the first coil  167 . As a result, a magnetic flux is generated around the first coil  167 , causing the movable iron core  164  to be displaced from the contact position to the separated position. Thereafter, the press contact of the wedge  34  and the contact surface  45  with the car guide rail  2  is released in the same manner as in Embodiment 2. 
     In the elevator apparatus as described above, the actuating mechanism  159  causes the pair of contact portions  157  to be displaced through the intermediation of the link members  158   a ,  158   b , whereby, in addition to the same effects as those of Embodiment 2, it is possible to reduce the number of actuating mechanisms  159  required for displacing the pair of contact portions  157 . 
     Embodiment 10 
       FIG. 17  is a partially cutaway side view showing a safety device according to Embodiment 10 of the present invention. Referring to  FIG. 17 , a safety device  175  has the wedge  34 , an actuator portion  176  connected to a lower portion of the wedge  34 , and the guide portion  36  arranged above the wedge  34  and fixed to the car  3 . 
     The actuator portion  176  has the actuating mechanism  159  constructed in the same manner as that of Embodiment 9, and a link member  177  displaceable through displacement of the movable portion  162  of the actuating mechanism  159 . 
     The actuating mechanism  159  is fixed to a lower portion of the car  3  so as to allow reciprocating displacement of the movable portion  162  in the horizontal direction with respect to the car  3 . The link member  177  is pivotably provided to a stationary shaft  180  fixed to a lower portion of the car  3 . The stationary shaft  180  is arranged below the actuating mechanism  159 . 
     The link member  177  has a first link portion  178  and a second link portion  179  which extend in different directions from. the stationary shaft  180  taken as the start point. The overall configuration of the link member  177  is substantially a prone shape. That is, the second link portion  179  is fixed to the first link portion  178 , and the first link portion  178  and the second link portion  179  are integrally pivotable about the stationary shaft  180 . 
     The length of the first link portion  178  is larger than that of the second link portion  179 . Further, an elongate hole  182  is provided at the distal end portion of the first link portion  178 . A slide pin  183 , which is slidably passed through the elongate hole  182 , is fixed to a lower portion of the wedge  34 . That is, the wedge  34  is slidably connected to the distal end portion of the first link portion  178 . The distal end portion of the movable portion  162  is pivotably connected to the distal end portion of the second link portion  179  through the intermediation of a connecting pin  181 . 
     The link member  177  is capable of reciprocating movement between a separated position where it keeps the wedge  34  separated away from and below the guide portion  36  and an actuating position where it causes the wedge  34  to wedge in between the car guide rail and the guide portion  36 . The movable portion  162  is projected from the drive portion  163  when the link member  177  is at the separated position, and it is retracted into the drive portion  163  when the link member is at the actuating position. 
     Next, operation is described. During normal operation, the link member  177  is located at the separated position due to the retracting motion of the movable portion  162  into the drive portion  163 . At this time, the wedge  34  is maintained at a spacing from the guide portion  36  and separated away from the car guide rail. 
     Thereafter, in the same manner as in Embodiment 2, an actuation signal is output from the output portion  32  to each safety device  175 , causing the movable portion  162  to advance. As a result, the link member  177  is pivoted about the stationary shaft  180  for displacement into the actuating position. This causes the wedge  34  to come into contact with the guide portion  36  and the car guide rail, wedging in between the guide portion  36  and the car guide rail. Braking is thus applied to the car  3 . 
     During the recovery phase, a recovery signal is transmitted from the output portion  32  to each safety device  175 , causing the movable portion  162  to be urged in the retracting direction. The car  3  is raised in this state, thus releasing the wedging of the wedge  34  in between the guide portion  36  and the car guide rail. 
     The above-described elevator apparatus also provides the same effects as those of Embodiment 2. 
     Embodiment 11 
       FIG. 18  is a schematic diagram showing an elevator apparatus according to Embodiment 11 of the present invention. In  FIG. 18 , a hoisting machine  101  serving as a driving device and a control panel  102  are provided in an upper portion within the hoistway  1 . The control panel  102  is electrically connected to the hoisting machine  101  and controls the operation of the elevator. The hoisting machine  101  has a driving device main body  103  including a motor and a driving sheave  104  rotated by the driving device main body  103 . A plurality of main ropes  4  are wrapped around the sheave  104 . The hoisting machine  101  further includes a deflector sheave  105  around which each main rope  4  is wrapped, and a hoisting machine braking device (deceleration braking device)  106  for braking the rotation of the drive sheave  104  to decelerate the car  3 . The car  3  and a counter weight  107  are suspended in the hoistway  1  by means of the main ropes  4 . The car  3  and the counterweight  107  are raised and lowered in the hoistway  1  by driving the hoisting machine  101 . 
     The safety device  33 , the hoisting machine braking device  106 , and the control panel  102  are electrically connected to a monitor device  108  that constantly monitors the state of the elevator. A car position sensor  109 , a car speed sensor  110 , and a car acceleration sensor  111  are also electrically connected to the monitor device  108 . The car position sensor  109 , the car speed sensor  110 , and the car acceleration sensor  111  respectively serve as a car position detecting portion for detecting the speed of the car  3 , a car speed detecting portion for detecting the speed of the car  3 , and a car acceleration detecting portion for detecting the acceleration of the car  3 . The car position sensor  109 , the car speed sensor  110 , and the car acceleration sensor  111  are provided in the hoistway  1 . 
     Detection means  112  for detecting the state of the elevator includes the car position sensor  109 , the car speed sensor  110 , and the car acceleration sensor  111 . Any of the following may be used for the car position sensor  109 : an encoder that detects the position of the car  3  by measuring the amount of rotation of a rotary member that rotates as the car  3  moves; a linear encoder that detects the position of the car  3  by measuring the amount of linear displacement of the car  3 ; an optical displacement measuring device which includes, for example, a projector and a photodetector provided in the hoistway  1  and a reflection plate provided in the car  3 , and which detects the position of the car  3  by measuring how long it takes for light projected from the projector to reach the photodetector. 
     The monitor device  108  includes a memory portion  113  and an output portion (calculation portion)  114 . The memory portion  113  stores in advance a variety of (in this embodiment, two) abnormality determination criteria (set data) serving as criteria for judging whether or not there is an abnormality in the elevator. The output portion  114  detects whether or not there is an abnormality in the elevator based on information from the detection means  112  and the memory portion  113 . The two kinds of abnormality determination criteria stored in the memory portion  113  in this embodiment are car speed abnormality determination criteria relating to the speed of the car  3  and car acceleration abnormality determination criteria relating to the acceleration of the car  3 . 
       FIG. 19  is a graph showing the car speed abnormality determination criteria stored in the memory portion  113  of  FIG. 18 . In  FIG. 19 , an ascending/descending section of the car  3  in the hoistway  1  (a section between one terminal floor and an other terminal floor) includes acceleration/deceleration sections and a constant speed section located between the acceleration/deceleration sections. The car  3  accelerates/decelerates in the acceleration/deceleration sections respectively located in the vicinity of the one terminal floor and the other terminal floor. The car  3  travels at a constant speed in the constant speed section. 
     The car speed abnormality determination criteria has three detection patterns each associated with the position of the car  3 . That is, a normal speed detection pattern (normal level)  115  that is the speed of the car  3  during normal operation, a first abnormal speed detection pattern (first abnormal level)  116  having a larger value than the normal speed detection pattern  115 , and a second abnormal speed detection pattern (second abnormal level)  117  having a larger value than the first abnormal speed detection pattern  116  are set, each in association with the position of the car  3 . 
     The normal speed detection pattern  115 , the first abnormal speed detection pattern  116 , and a second abnormal speed detection pattern  117  are set so as to have a constant value in the constant speed section, and to have a value continuously becoming smaller toward the terminal floor in each of the acceleration and deceleration sections. The difference in value between the first abnormal speed detection pattern  116  and the normal speed detection pattern  115 , and the difference in value between the second abnormal speed detection pattern  117  and the first abnormal speed detection pattern  116 , are set to be substantially constant at all locations in the ascending/descending section. 
       FIG. 20  is a graph showing the car acceleration abnormality determination criteria stored in the memory portion  113  of  FIG. 18 . In  FIG. 20 , the car acceleration abnormality determination criteria has three detection patterns each associated with the position of the car  3 . That is, a normal acceleration detection pattern (normal level)  118  that is the acceleration of the car  3  during normal operation, a first abnormal acceleration detection pattern (first abnormal level)  119  having a larger value than the normal acceleration detection pattern  118 , and a second abnormal acceleration detection pattern (second abnormal level)  120  having a larger value than the first abnormal acceleration detection pattern  119  are set, each in association with the position of the car  3 . 
     The normal acceleration detection pattern  118 , the first abnormal acceleration detection pattern  119 , and the second abnormal acceleration detection pattern  120  are each set so as to have a value of zero in the constant speed section, a positive value in one of the acceleration/deceleration section, and a negative value in the other acceleration/deceleration section. The difference in value between the first abnormal acceleration detection pattern  119  and the normal acceleration detection pattern  118 , and the difference in value between the second abnormal acceleration detection pattern  120  and the first abnormal acceleration detection pattern  119 , are set to be substantially constant at all locations in the ascending/descending section. 
     That is, the memory portion  113  stores the normal speed detection pattern  115 , the first abnormal speed detection pattern  116 , and the second abnormal speed detection pattern  117  as the car speed abnormality determination criteria, and stores the normal acceleration detection pattern  118 , the first abnormal acceleration detection pattern  119 , and the second abnormal acceleration detection pattern  120  as the car acceleration abnormality determination criteria. 
     The safety device  33 , the control panel  102 , the hoisting machine braking device  106 , the detection means  112 , and the memory portion  113  are electrically connected to the output portion  114 . Further, a position detection signal, a speed detection signal, and an acceleration detection signal are input to the output portion  114  continuously over time from the car position sensor  109 , the car speed sensor  110 , and the car acceleration sensor  111 . The output portion  114  calculates the position of the car  3  based on the input position detection signal. The output portion  114  also calculates the speed of the car  3  and the acceleration of the car  3  based on the input speed detection signal and the input acceleration detection signal, respectively, as a variety of (in this example, two) abnormality determination factors. 
     The output portion  114  outputs an actuation signal (trigger signal) to the hoisting machine braking device  106  when the speed of the car  3  exceeds the first abnormal speed detection pattern  116 , or when the acceleration of the car  3  exceeds the first abnormal acceleration detection pattern  119 . At the same time, the output portion  114  outputs a stop signal to the control panel  102  to stop the drive of the hoisting machine  101 . When the speed of the car  3  exceeds the second abnormal speed detection pattern  117 , or when the acceleration of the car  3  exceeds the second abnormal acceleration detection pattern  120 , the output portion  114  outputs an actuation signal to the hoisting machine braking device  106  and the safety device  33 . That is, the output portion  114  determines to which braking means it should output the actuation signals according to the degree of the abnormality in the speed and the acceleration of the car  3 . 
     Otherwise, this embodiment is of the same construction as Embodiment 2. 
     Next, operation is described. When the position detection signal, the speed detection signal, and the acceleration detection signal are input to the output portion  114  from the car position sensor  109 , the car speed sensor  110 , and the car acceleration sensor  111 , respectively, the output portion  114  calculates the position, the speed, and the acceleration of the car  3  based on the respective detection signals thus input. After that, the output portion  114  compares the car speed abnormality determination criteria and the car acceleration abnormality determination criteria obtained from the memory portion  113  with the speed and the acceleration of the car  3  calculated based on the respective detection signals input. Through this comparison, the output portion  114  detects whether or not there is an abnormality in either the speed or the acceleration of the car  3 . 
     During normal operation, the speed of the car  3  has approximately the same value as the normal speed detection pattern, and the acceleration of the car  3  has approximately the same value as the normal acceleration detection pattern. Thus, the output portion  114  detects that there is no abnormality in either the speed or the acceleration of the car  3 , and normal operation of the elevator continues. 
     When, for example, the speed of the car  3  abnormally increases and exceeds the first abnormal speed detection pattern  116  due to some cause, the output portion  114  detects that there is an abnormality in the speed of the car  3 . Then, the output portion  114  outputs an actuation signal and a stop signal to the hoisting machine braking device  106  and the control panel  102 , respectively. As a result, the hoisting machine  101  is stopped, and the hoisting machine braking device  106  is operated to brake the rotation of the drive sheave  104 . 
     When the acceleration of the car  3  abnormally increases and exceeds the first abnormal acceleration set value  119 , the output portion  114  outputs an actuation signal and a stop signal to the hoisting machine braking device  106  and the control panel  102 , respectively, thereby braking the rotation of the drive sheave  104 . 
     If the speed of the car  3  continues to increase after the actuation of the hoisting machine braking device  106  and exceeds the second abnormal speed set value  117 , the output portion  114  outputs an actuation signal to the safety device  33  while still outputting the actuation signal to the hoisting machine braking device  106 . Thus, the safety device  33  is actuated and the car  3  is braked through the same operation as that of Embodiment 2. 
     Further, when the acceleration of the car  3  continues to increase after the actuation of the hoisting machine braking device  106 , and exceeds the second abnormal acceleration set value  120 , the output portion  114  outputs an actuation signal to the safety device  33  while still outputting the actuation signal to the hoisting machine braking device  106 . Thus, the safety device  33  is actuated. 
     With such an elevator apparatus, the monitor device  108  obtains the speed of the car  3  and the acceleration of the car  3  based on the information from the detection means  112  for detecting the state of the elevator. When the monitor device  108  judges that there is an abnormality in the obtained speed of the car  3  or the obtained acceleration of the car  3 , the monitor device  108  outputs an actuation signal to at least one of the hoisting machine braking device  106  and the safety device  33 . That is, judgment of the presence or absence of an abnormality is made by the monitor device  108  separately for a variety of abnormality determination factors such as the speed of the car and the acceleration of the car. Accordingly, an abnormality in the elevator can be detected earlier and more reliably. Therefore, it takes a shorter time for the braking force on the car  3  to be generated after occurrence of an abnormality in the elevator. 
     Further, the monitor device  108  includes the memory portion  113  that stores the car speed abnormality determination criteria used for judging whether or not there is an abnormality in the speed of the car  3 , and the car acceleration abnormality determination criteria used for judging whether or not there is an abnormality in the acceleration of the car  3 . Therefore, it is easy to change the judgment criteria used for judging whether or not there is an abnormality in the speed and the acceleration of the car  3 , respectively, allowing easy adaptation to design changes or the like of the elevator. 
     Further, the following patterns are set for the car speed abnormality determination criteria: the normal speed detection pattern  115 , the first abnormal speed detection pattern  116  having a larger value than the normal speed detection pattern  115 , and the second abnormal speed detection pattern  117  having a larger value than the first abnormal speed detection pattern  116 . When the speed of the car  3  exceeds the first abnormal speed detection pattern  116 , the monitor device  108  outputs an actuation signal to the hoisting machine braking device  106 , and when the speed of the car  3  exceeds the second abnormal speed detection pattern  117 , the monitor device  108  outputs an actuation signal to the hoisting machine braking device  106  and the safety device  33 . Therefore, the car  3  can be braked stepwise according to the degree of this abnormality in the speed of the car  3 . As a result, the frequency of large shocks exerted on the car  3  can be reduced, and the car  3  can be more reliably stopped. 
     Further, the following patterns are set for the car acceleration abnormality determination criteria: the normal acceleration detection pattern  118 , the first abnormal acceleration detection pattern  119  having a larger value than the normal acceleration detection pattern  118 , and the second abnormal acceleration detection pattern  120  having a larger value than the first abnormal acceleration detection pattern  119 . When the acceleration of the car  3  exceeds the first abnormal acceleration detection pattern  119 , the monitor device  108  outputs an actuation signal to the hoisting machine braking device  106 ,and when the acceleration of the car  3  exceeds the second abnormal acceleration detection pattern  120 , the monitor device  108  outputs an actuation signal to the hoisting machine braking device  106  and the safety device  33 . Therefore, the car  3  can be braked stepwise according to the degree of an abnormality in the acceleration of the car  3 . Normally, an abnormality occurs in the acceleration of the car  3  before an abnormality occurs in the speed of the car  3 . As a result, the frequency of large shocks exerted on the car  3  can be reduced, and the car  3  can be more reliably stopped. 
     Further, the normal speed detection pattern  115 , the first abnormal speed detection pattern  116 , and the second abnormal speed detection pattern  117  are each set in association with the position of the car  3 . Therefore, the first abnormal speed detection pattern  116  and the second abnormal speed detection pattern  117  each can be set in association with the normal speed detection pattern  115  at all locations in the ascending/descending section of the car  3 . In the acceleration/deceleration sections, in particular, the first abnormal speed detection pattern  116  and the second abnormal speed detection pattern  117  each can be set to a relatively small value because the normal speed detection pattern  115  has a small value. As a result, the impact acting on the car  3  upon braking can be mitigated. 
     It should be noted that in the above-described example, the car speed sensor  110  is used when the monitor  108  obtains the speed of the car  3 . However, instead of using the car speed sensor  110 , the speed of the car  3  may be obtained from the position of the car  3  detected by the car position sensor  109 . That is, the speed of the car  3  may be obtained by differentiating the position of the car  3  calculated by using the position detection signal from the car position sensor  109 . 
     Further, in the above-described example, the car acceleration sensor  111  is used when the monitor  108  obtains the acceleration of the car  3 . However, instead of using the car acceleration sensor  111 , the acceleration of the car  3  may be obtained from the position of the car  3  detected by the car position sensor  109 . That is, the acceleration of the car  3  may be obtained by differentiating, twice, the position of the car  3  calculated by using the position detection signal from the car position sensor  109 . 
     Further, in the above-described example, the output portion  114  determines to which braking means it should output the actuation signals according to the degree of the abnormality in the speed and acceleration of the car  3  constituting the abnormality determination factors. However, the braking means to which the actuation signals are to be output may be determined in advance for each abnormality determination factor. 
     Embodiment 12 
       FIG. 21  is a schematic diagram showing an elevator apparatus according to Embodiment 12 of the present invention. In  FIG. 21 , a plurality of hall call buttons  125  are provided in the hall of each floor. A plurality of destination floor buttons  126  are provided in the car  3 . A monitor device  127  has the output portion  114 . An abnormality determination criteria generating device  128  for generating a car speed abnormality determination criteria and a car acceleration abnormality determination criteria is electrically connected to the output portion  114 . The abnormality determination criteria generating device  128  is electrically connected to each hall call button  125  and each destination floor button  126 . A position detection signal is input to the abnormality determination criteria generating device  128  from the car position sensor  109  via the output portion  114 . 
     The abnormality determination criteria generating device  128  includes a memory portion  129  and a generation portion  130 . The memory portion  129  stores a plurality of car speed abnormality determination criteria and a plurality of car acceleration abnormality determination criteria, which serve as abnormal judgment criteria for all the cases where the car  3  ascends and descends between the floors. The generation portion  130  selects a car speed abnormality determination criteria and a car acceleration abnormality determination criteria one by one from the memory portion  129 , and outputs the car speed abnormality determination criteria and the car acceleration abnormality determination criteria to the output portion  114 . 
     Each car speed abnormality determination criteria has three detection patterns each associated with the position of the car  3 , which are similar to those of  FIG. 19  of Embodiment 11. Further, each car acceleration abnormality determination criteria has three detection patterns each associated with the position of the car  3 , which are similar to those of  FIG. 20  of Embodiment 11. 
     The generation portion  130  calculates a detection position of the car  3  based on information from the car position sensor  109 , and calculates a target floor of the car  3  based on information from at least one of the hall call buttons  125  and the destination floor buttons  126 . The generation portion  130  selects one by one a car speed abnormality determination criteria and a car acceleration abnormality determination criteria used for a case where the calculated detection position and the target floor are one and the other of the terminal floors. 
     Otherwise, this embodiment is of the same construction as Embodiment 11. 
     Next, operation is described. A position detection signal is constantly input to the generation portion  130  from the car position sensor  109  via the output portion  114 . When a passenger or the like selects any one of the hall call buttons  125  or the destination floor buttons  126  and a call signal is input to the generation portion  130  from the selected button, the generation portion  130  calculates a detection position and a target floor of the car  3  based on the input position detection signal and the input call signal, and selects one out of both a car speed abnormality determination criteria and a car acceleration abnormality determination criteria. After that, the generation portion  130  outputs the selected car speed abnormality determination criteria and the selected car acceleration abnormality determination criteria to the output portion  114 . 
     The output portion  114  detects whether or not there is an abnormality in the speed and the acceleration of the car  3  in the same way as in Embodiment 11. Thereafter, this embodiment is of the same operation as Embodiment 9. 
     With such an elevator apparatus, the car speed abnormality determination criteria and the car acceleration abnormality determination criteria are generated based on the information from at least one of the hall call buttons  125  and the destination floor buttons  126 . Therefore, it is possible to generate the car speed abnormality determination criteria and the car acceleration abnormality determination criteria corresponding to the target floor. As a result, the time it takes for the braking force on the car  3  to be generated after occurrence of an abnormality in the elevator can be reduced even when a different target floor is selected. 
     It should be noted that in the above-described example, the generation portion  130  selects one out of both the car speed abnormality determination criteria and car acceleration abnormality determination criteria from among a plurality of car speed abnormality determination criteria and a plurality of car acceleration abnormality determination criteria stored in the memory portion  129 . However, the generation portion may directly generate an abnormal speed detection pattern and an abnormal acceleration detection pattern based on the normal speed pattern and the normal acceleration pattern of the car  3  generated by the control panel  102 . 
     Embodiment 13 
       FIG. 22  is a schematic diagram showing an elevator apparatus according to Embodiment 13 of the present invention. In this example, each of the main ropes  4  is connected to an upper portion of the car  3  via a rope fastening device  131  ( FIG. 23 ). The monitor device  108  is mounted on an upper portion of the car  3 . The car position sensor  109 , the car speed sensor  110 , and a plurality of rope sensors  132  are electrically connected to the output portion  114 . Rope sensors  132  are provided in the rope fastening device  131 , and each serve as a rope break detecting portion for detecting whether or not a break has occurred in each of the ropes  4 . The detection means  112  includes the car position sensor  109 , the car speed sensor  110 , and the rope sensors  132 . 
     The rope sensors  132  each output a rope brake detection signal to the output portion  114  when the main ropes  4  break. The memory portion  113  stores the car speed abnormality determination criteria similar to that of Embodiment 11 shown in  FIG. 19 , and a rope abnormality determination criteria used as a reference for judging whether or not there is an abnormality in the main ropes  4 . 
     A first abnormal level indicating a state where at least one of the main ropes  4  have broken, and a second abnormal level indicating a state where all of the main ropes  4  has broken are set for the rope abnormality determination criteria. 
     The output portion  114  calculates the position of the car  3  based on the input position detection signal. The output portion  114  also calculates the speed of the car  3  and the state of the main ropes  4  based on the input speed detection signal and the input rope brake signal, respectively, as a variety of (in this example, two) abnormality determination factors. 
     The output portion  114  outputs an actuation signal (trigger signal) to the hoisting machine braking device  106  when the speed of the car  3  exceeds the first abnormal speed detection pattern  116  ( FIG. 19 ), or when at least one of the main ropes  4  breaks. When the speed of the car  3  exceeds the second abnormal speed detection pattern  117  ( FIG. 19 ), or when all of the main ropes  4  break, the output portion  114  outputs an actuation signal to the hoisting machine braking device  106  and the safety device  33 . That is, the output portion  114  determines to which braking means it should output the actuation signals according to the degree of an abnormality in the speed of the car  3  and the state of the main ropes  4 . 
       FIG. 23  is a diagram showing the rope fastening device  131  and the rope sensors  132  of  FIG. 22 .  FIG. 24  is a diagram showing a state where one of the main ropes  4  of  FIG. 23  has broken. In  FIGS. 23 and 24 , the rope fastening device  131  includes a plurality of rope connection portions  134  for connecting the main ropes  4  to the car  3 . The rope connection portions  134  each include an spring  133  provided between the main rope  4  and the car  3 . The position of the car  3  is displaceable with respect to the main ropes  4  by the expansion and contraction of the springs  133 . 
     The rope sensors  132  are each provided to the rope connection portion  134 . The rope sensors  132  each serve as a displacement measuring device for measuring the amount of expansion of the spring  133 . Each rope sensor  132  constantly outputs a measurement signal corresponding to the amount of expansion of the spring  133  to the output portion  114 . A measurement signal obtained when the expansion of the spring  133  returning to its original state has reached a predetermined amount is input to the output portion  114  as a break detection signal. It should be noted that each of the rope connection portions  134  may be provided with a scale device that directly measures the tension of the main ropes  4 . 
     Otherwise, this embodiment is of the same construction as Embodiment 11. 
     Next, operation is described. When the position detection signal, the speed detection signal, and the break detection signal are input to the output portion  114  from the car position sensor  109 , the car speed sensor  110 , and each rope sensor  131 , respectively, the output portion  114  calculates the position of the car  3 , the speed of the car  3 , and the number of main ropes  4  that have broken based on the respective detection signals thus input. After that, the output portion  114  compares the car speed abnormality determination criteria and the rope abnormality determination criteria obtained from the memory portion  113  with the speed of the car  3  and the number of broken main ropes  4  calculated based on the respective detection signals input. Through this comparison, the output portion  114  detects whether or not there is an abnormality in both the speed of the car  3  and the state of the main ropes  4 . 
     During normal operation, the speed of the car  3  has approximately the same value as the normal speed detection pattern, and the number of broken main ropes  4  is zero. Thus, the output portion  114  detects that there is no abnormality in either the speed of the car  3  or the state of the main ropes  4 , and normal operation of the elevator continues. 
     When, for example, the speed of the car  3  abnormally increases and exceeds the first abnormal speed detection pattern  116  ( FIG. 19 ) for some reason, the output portion  114  detects that there is an abnormality in the speed of the car  3 . Then, the output portion  114  outputs an actuation signal and a stop signal to the hoisting machine braking device  106  and the control panel  102 , respectively. As a result, the hoisting machine  101  is stopped, and the hoisting machine raking device  106  is operated to brake the rotation of the drive sheave  104 . 
     Further, when at least one of the main ropes  4  has broken, the output portion  114  outputs an actuation signal and a stop signal to the hoisting machine braking device  106  and the control panel  102 , respectively, thereby braking the rotation of the drive sheave  104 . 
     If the speed of the car  3  continues to increase after the actuation of the hoisting machine braking device  106  and exceeds the second abnormal speed set value  117  ( FIG. 19 ), the output portion  114  outputs an actuation signal to the safety device  33  while still outputting the actuation signal to the hoisting machine braking device  106 . Thus, the safety device  33  is actuated and the car  3  is braked through the same operation as that of Embodiment 2. 
     Further, if all the main ropes  4  break after the actuation of the hoisting machine braking device  106 , the output portion  114  outputs an actuation signal to the safety device  33  while still outputting the actuation signal to the hoisting machine braking device  106 . Thus, the safety device  33  is actuated. 
     With such an elevator apparatus, the monitor device  108  obtains the speed of the car  3  and the state of the main ropes  4  based on the information from the detection means  112  for detecting the state of the elevator. When the monitor device  108  judges that there is an abnormality in the obtained speed of the car  3  or the obtained state of the main ropes  4 , the monitor device  108  outputs an actuation signal to at least one of the hoisting machine braking device  106  and the safety device  33 . This means that the number of targets for abnormality detection increases, allowing abnormality detection of not only the speed of the car  3  but also the state of the main ropes  4 . Accordingly, an abnormality in the elevator can be detected earlier and more reliably. Therefore, it takes a shorter time for the braking force on the car  3  to be generated after occurrence of an abnormality in the elevator. 
     It should be noted that in the above-described example, the rope sensor  132  is disposed in the rope fastening device  131  provided to the car  3 . However, the rope sensor  132  may be disposed in a rope fastening device provided to the counterweight  107 . 
     Further, in the above-described example, the present invention is applied to an elevator apparatus of the type in which the car  3  and the counterweight  107  are suspended in the hoistway  1  by connecting one end portion and the other end portion of the main rope  4  to the car  3  and the counterweight  107 , respectively. However, the present invention may also be applied to an elevator apparatus of the type in which the car  3  and the counterweight  107  are suspended in the hoistway  1  by wrapping the main rope  4  around a car suspension sheave and a counterweight suspension sheave, with one end portion and the other end portion of the main rope  4  connected to structures arranged in the hoistway  1 . In this case, the rope sensor is disposed in the rope fastening device provided to the structures arranged in the hoistway  1 . 
     Embodiment 14 
       FIG. 25  is a schematic diagram showing an elevator apparatus according to Embodiment 14 of the present invention. In this example, a rope sensor  135  serving as a rope brake detecting portion is constituted by lead wires embedded in each of the main ropes  4 . Each of the lead wires extends in the longitudinal direction of the rope  4 . Both end portion of each lead wire are electrically connected to the output portion  114 . A weak current flows in the lead wires. Cut-off of current flowing in each of the lead wires is input as a rope brake detection signal to the output portion  114 . 
     Otherwise, this embodiment is of the same construction as Embodiment 13. 
     With such an elevator apparatus, a break in any main rope  4  is detected based on cutting off of current supply to any lead wire embedded in the main ropes  4 . Accordingly, whether or not the rope has broken is more reliably detected without being affected by a change of tension of the main ropes  4  due to acceleration and deceleration of the car  3 . 
     Embodiment 15 
       FIG. 26  is a schematic diagram showing an elevator apparatus according to Embodiment 15 of the present invention. In  FIG. 26 , the car position sensor  109 , the car speed sensor  110 , and a door sensor  140  are electrically connected to the output portion  114 . The door sensor  140  serves as an entrance open/closed detecting portion for detecting open/closed of the car entrance  26 . The detection means  112  includes the car position sensor  109 , the car speed sensor  110 , and the door sensor  140 . 
     The door sensor  140  outputs a door-closed detection signal to the output portion  114  when the car entrance  26  is closed. The memory portion  113  stores the car speed abnormality determination criteria similar to that of Embodiment 11 shown in  FIG. 19 , and an entrance abnormality determination criteria used as a reference for judging whether or not there is an abnormality in the open/close state of the car entrance  26 . If the car ascends/descends while the car entrance  26  is not closed, the entrance abnormality determination criteria regards this as an abnormal state. 
     The output portion  114  calculates the position of the car  3  based on the input position detection signal. The output portion  114  also calculates the speed of the car  3  and the state of the car entrance  26  based on the input speed detection signal and the input door-closing detection signal, respectively, as a variety of (in this example, two) abnormality determination factors. 
     The output portion  114  outputs an actuation signal to the hoisting machine braking device  104  if the car ascends/descends while the car entrance  26  is not closed, or if the speed of the car  3  exceeds the first abnormal speed detection pattern  116  ( FIG. 19 ). If the speed of the car  3  exceeds the second abnormal speed detection pattern  117  ( FIG. 19 ), the output portion  114  outputs an actuation signal to the hoisting machine braking device  106  and the safety device  33 . 
       FIG. 27  is a perspective view of the car  3  and the door sensor  140  of  FIG. 26 .  FIG. 28  is a perspective view showing a state in which the car entrance  26  of  FIG. 27  is open. In  FIGS. 27 and 28 , the door sensor  140  is provided at an upper portion of the car entrance  26  and in the center of the car entrance  26  with respect to the width direction of the car  3 . The door sensor  140  detects displacement of each of the car doors  28  into the door-closed position, and outputs the door-closed detection signal to the output portion  114 . 
     It should be noted that a contact type sensor, a proximity sensor, or the like maybe used for the door sensor  140 . The contact type sensor detects closing of the doors through its contact with a fixed portion secured to each of the car doors  28 . The proximity sensor detects closing of the doors without contacting the car doors  28 . Further, a pair of hall doors  142  for opening/closing a hall entrance  141  are provided at the hall entrance  141 . The hall doors  142  are engaged to the car doors  28  by means of an engagement device (not shown) when the car  3  rests at a hall floor, and are displaced together with the car doors  28 . 
     Otherwise, this embodiment is of the same construction as Embodiment 11. 
     Next, operation is described. When the position detection signal, the speed detection signal, and the door-closed detection signal are input to the output portion  114  from the car position sensor  109 , the car speed sensor  110 , and the door sensor  140 , respectively, the output portion  114  calculates the position of the car  3 , the speed of the car  3 , and the state of the car entrance  26  based on the respective detection signals thus input. After that, the output portion  114  compares the car speed abnormality determination criteria and the drive device state abnormality determination criteria obtained from the memory portion  113  with the speed of the car  3  and the state of the car of the car doors  28  calculated based on the respective detection signals input. Through this comparison, the output portion  114  detects whether or not there is an abnormality in each of the speed of the car  3  and the state of the car entrance  26 . 
     During normal operation, the speed of the car  3  has approximately the same value as the normal speed detection pattern, and the car entrance  26  is closed while the car  3  ascends/descends. Thus, the output portion  114  detects that there is no abnormality in each of the speed of the car  3  and the state of the car entrance  26 , and normal operation of the elevator continues. 
     When, for instance, the speed of the car  3  abnormally increases and exceeds the first abnormal speed detection pattern  116  ( FIG. 19 ) for some reason, the output portion  114  detects that there is an abnormality in the speed of the car  3 . Then, the output portion  114  outputs an actuation signal and a stop signal to the hoisting machine braking device  106  and the control panel  102 , respectively. As a result, the hoisting machine  101  is stopped, and the hoisting machine braking device  106  is actuated to brake the rotation of the drive sheave  104 . 
     Further, the output portion  114  also detects an abnormality in the car entrance  26  when the car  3  ascends/descends while the car entrance  26  is not closed. Then, the output portion  114  outputs an actuation signal and a stop signal to the hoisting machine braking device  106  and the control panel  102 , respectively, thereby braking the rotation of the drive sheave  104 . 
     When the speed of the car  3  continues to increase after the actuation of the hoisting machine braking device  106 , and exceeds the second abnormal speed set value  117  ( FIG. 19 ), the output portion  114  outputs an actuation signal to the safety device  33  while still outputting the actuation signal to the hoisting machine braking device  106 . Thus, the safety device  33  is actuated and the car  3  is braked through the same operation as that of Embodiment 2. 
     With such an elevator apparatus, the monitor device  108  obtains the speed of the car  3  and the state of the car entrance  26  based on the information from the detection means  112  for detecting the state of the elevator. When the monitor device  108  judges that there is an abnormality in the obtained speed of the car  3  or the obtained state of the car entrance  26 , the monitor device  108  outputs an actuation signal to at least one of the hoisting machine braking device  106  and the safety device  33 . This means that the number of targets for abnormality detection increases, allowing abnormality detection of not only the speed of the car  3  but also the state of the car entrance  26 . Accordingly, abnormalities of the elevator can be detected earlier and more reliably. Therefore, it takes less time for the braking force on the car  3  to be generated after occurrence of an abnormality in the elevator. 
     It should be noted that while in the above-described example, the door sensor  140  only detects the state of the car entrance  26 , the door sensor  140  may detect both the state of the car entrance  26  and the state of the elevator hall entrance  141 . In this case, the door sensor  140  detects displacement of the elevator hall doors  142  into the door-closed position, as well as displacement of the car doors  28  into the door-closed position. With this construction, abnormality in the elevator can be detected even when only the car doors  28  are displaced due to a problem with the engagement device or the like that engages the car doors  28  and the elevator hall doors  142  with each other. 
     Embodiment 16 
       FIG. 29  is a schematic diagram showing an elevator apparatus according to Embodiment 16 of the present invention.  FIG. 30  is a diagram showing an upper portion of the hoistway  1  of  FIG. 29 . In  FIGS. 29 and 30 , a power supply cable  150  is electrically connected to the hoisting machine  110 . Drive power is supplied to the hoisting machine  101  via the power supply cable  150  through control of the control panel  102 . 
     A current sensor  151  serving as a drive device detection portion is provided to the power supply cable  150 . The current sensor  151  detects the state of the hoisting machine  101  by measuring the current flowing in the power supply cable  150 . The current sensor  151  outputs to the output portion  114  a current detection signal (drive device state detection signal) corresponding to the value of a current in the power supply cable  150 . The current sensor  151  is provided in the upper portion of the hoistway  1 . A current transformer (CT) that measures an induction current generated in accordance with the amount of current flowing in the power supply cable  150  is used as the current sensor  151 , for example. 
     The car position sensor  109 , the car speed sensor  110 , and the current sensor  151  are electrically connected to the output portion  114 . The detection means  112  includes the car position sensor  109 , the car speed sensor  110 , and the current sensor  151 . 
     The memory portion  113  stores the car speed abnormality determination criteria similar to that of Embodiment 11 shown in  FIG. 19 , and a drive device abnormality determination criteria used as a reference for determining whether or not there is an abnormality in the state of the hoisting machine  101 . 
     The drive device abnormality determination criteria has three detection patterns. That is, a normal level that is the current value flowing in the power supply cable  150  during normal operation, a first abnormal level having a larger value than the normal level, and a second abnormal level having a larger value than the first abnormal level, are set for the drive device abnormality determination criteria. 
     The output portion  114  calculates the position of the car  3  based on the input position detection signal. The output portion  114  also calculates the speed of the car  3  and the state of the hoisting device  101  based on the input speed detection signal and the input current detection signal, respectively, as a variety of (in this example, two) abnormality determination factors. 
     The output portion  114  outputs an actuation signal (trigger signal) to the hoisting machine braking device  106  when the speed of the car  3  exceeds the first abnormal speed detection pattern  116  ( FIG. 19 ), or when the amount of the current flowing in the power supply cable  150  exceeds the value of the first abnormal level of the drive device abnormality determination criteria. When the speed of the car  3  exceeds the second abnormal speed detection pattern  117  ( FIG. 19 ), or when the amount of the current flowing in the power supply cable  150  exceeds the value of the second abnormal level of the drive device abnormality determination criteria, the output portion  114  outputs an actuation signal to the hoisting machine braking device  106  and the safety device  33 . That is, the output portion  114  determines to which braking means it should output the actuation signals according to the degree of abnormality in each of the speed of the car  3  and the state of the hoisting machine  101 . 
     Otherwise, this embodiment is of the same construction as embodiment 11. 
     Next, operation is described. When the position detection signal, the speed detection signal, and the current detection signal are input to the output portion  114  from the car position sensor  109 , the car speed sensor  110 , and the current sensor  151 , respectively, the output portion  114  calculates the position of the car  3 , the speed of the car  3 , and the amount of current flowing in the power supply cable  151  based on the respective detection signals thus input. After that, the output portion  114  compares the car speed abnormality determination criteria and the drive device state abnormality determination criteria obtained from the memory portion  113  with the speed of the car  3  and the amount of the current flowing into the current supply cable  150  calculated based on the respective detection signals input. Through this comparison, the output portion  114  detects whether or not there is an abnormality in each of the speed of the car  3  and the state of the hoisting machine  101 . 
     During normal operation, the speed of the car  3  has approximately the same value as the normal speed detection pattern  115  ( FIG.19 ), and the amount of current flowing in the power supply cable  150  is at the normal level. Thus, the output portion  114  detects that there is no abnormality in each of the speed of the car  3  and the state of the hoisting machine  101 , and normal operation of the elevator continues. 
     If, for instance, the speed of the car  3  abnormally increases and exceeds the first abnormal speed detection pattern  116  ( FIG. 19 ) for some reason, the output portion  114  detects that there is an abnormality in the speed of the car  3 . Then, the output portion  114  outputs an actuation signal and a stop signal to the hoisting machine braking device  106  and the control panel  102 , respectively. As a result, the hoisting machine  101  is stopped, and the hoisting machine braking device  106  is actuated to brake the rotation of the drive sheave  104 . 
     If the amount of current flowing in the power supply cable  150  exceeds the first abnormal level in the drive device state abnormality determination criteria, the output portion  114  outputs an actuation signal and a stop signal to the hoisting machine braking device  106  and the control panel  102 , respectively, thereby braking the rotation of the drive sheave  104 . 
     When the speed of the car  3  continues to increase after the actuation of the hoisting machine braking device  106 , and exceeds the second abnormal speed set value  117  ( FIG. 19 ), the output portion  114  outputs an actuation signal to the safety device  33  while still outputting the actuation signal to the hoisting machine braking device  106 . Thus, the safety device  33  is actuated and the car  3  is braked through the same operation as that of Embodiment 2. 
     When the amount of current flowing in the power supply cable  150  exceeds the second abnormal level of the drive device state abnormality determination criteria after the actuation of the hoisting machine braking device  106 , the output portion  114  outputs an actuation signal to the safety device  33  while still outputting the actuation signal to the hoisting machine braking device  106 . Thus, the safety device  33  is actuated. 
     With such an elevator apparatus, the monitor device  108  obtains the speed of the car  3  and the state of the hoisting machine  101  based on the information from the detection means  112  for detecting the state of the elevator. When the monitor device  108  judges that there is an abnormality in the obtained speed of the car  3  or the state of the hoisting machine  101 , the monitor device  108  outputs an actuation signal to at least one of the hoisting machine braking device  106  and the safety device  33 . This means that the number of targets for abnormality detection increases, and it takes a shorter time for the braking force on the car  3  to be generated after occurrence of an abnormality in the elevator. 
     It should be noted that in the above-described example, the state of the hoisting machine  101  is detected using the current sensor  151  for measuring the amount of the current flowing in the power supply cable  150 . However the state of the hoisting machine  101  may be detected using a temperature sensor for measuring the temperature of the hoisting machine  101 . 
     Further, in Embodiments 11 through 16 described above, the output portion  114  outputs an actuation signal to the hoisting machine braking device  106  before outputting an actuation signal to the safety device  33 . However, the output portion  114  may instead output an actuation signal to one of the following brakes: a car brake for braking the car  3  by gripping the car guide rail  2 , which is mounted on the car  3  independently of the safety device  33 ; a counterweight brake mounted on the counterweight  107  for braking the counterweight  107  by gripping a counterweight guide rail for guiding the counter weight  107 ; and a rope brake mounted in the hoistway  1  for braking the main ropes  4  by locking up the main ropes  4 . 
     Further, in Embodiments 1 through 16 described above, the electric cable is used as the transmitting means for supplying power from the output portion to the safety device. However, a wireless communication device having a transmitter provided at the output portion and a receiver provided at the safety device may be used instead. Alternatively, an optical fiber cable that transmits an optical signal may be used. 
     Embodiment 17 
       FIG. 31  is a schematic diagram showing an elevator apparatus according to Embodiment 17 of the present invention. Referring to  FIG. 31 , a car guide rail  2  has a plurality of unit rails  201  that are vertically connected to each other. Accordingly, a joint  202  is provided between each of the unit rails  201 . 
     The car  3  is provided with a guide roller  203  that contacts the car guide rail  2 . The guide roller  203  rolls on the car guide rail  2  as the car  3  travels. The guide roller  203  is provided with an encoder  204  serving as a roller sensor. The encoder  204  outputs a rotational position signal (pulse signal) that is based on the rotational position of the guide roller  203 . Further, provided on top of the car  3  is a rail joint detecting device  205  for detecting the presence/absence of the joint  202 . The rail joint detecting device  205  outputs information on the presence/absence of the joint  202  thus detected. 
     Mounted in the control panel  102  are a car position calculating circuit (car position detecting portion)  206  for obtaining the position of the car  3  based on information (rotational position signal) from the encoder  204 , a car speed calculating circuit  207  for obtaining the speed of the car  3  based on information on the position of the car  3  as obtained by the car position calculating circuit  206 , a car position correcting circuit (car position correcting portion)  208  for correcting the position information on the car  3  from the car position calculating circuit  206  based on the information on the presence/absence of the joint  202  as detected by the rail joint detecting device  205 , and a control device  209  for controlling the operation of the elevator based on information from each of the car speed calculating circuit  207  and the car position correcting circuit  208 . 
     Position information on each joint  202  is set in advance in the car position correcting circuit  208 . When the presence of the joint  202  is detected by the rail joint detecting device  205 , the car position correcting circuit  208  acquires the set position information on the joint  202  as position information on the car  3 . Further, when position information on the car  3  as acquired based on information from the car position calculating circuit  206  and that as acquired based on information from the rail joint detecting device  205  match each other, the car position correcting circuit  208  outputs the matched position information on the car  3  to the control device  209  as corrected position information on the car  3 , and when the respective pieces of position information on the car  3  are different from each other, the car position correcting circuit  208  outputs to the control device  209  the position information on the car  3  acquired based on information from the rail joint detecting device  205 , as corrected position information on the car  3 . 
     The control device  209  stores the same car speed abnormality judgment criteria as those of Embodiment 11 shown in  FIG. 19 . The control device  209  outputs an actuation signal (trigger signal) to the hoisting machine braking device  104  ( FIG. 18 ) when the speed of the car  3  as obtained from the car speed calculating circuit  207  exceeds the first abnormality speed detection pattern  116  ( FIG. 19 ) at the position of the car  3  as obtained from the car position correcting circuit  208 . Further, when, at the position of the car  3  as obtained from the car speed calculating circuit  208 , the speed of the car  3  as obtained from the car speed calculating circuit  207  exceeds the second abnormal speed detection pattern  117  ( FIG. 19 ), the control device  209  outputs an actuation signal to the safety device  33  while continuing to output the actuation signal to the hoisting machine braking device  104 . That is, the control device  209  controls the operation of the elevator based on information on the speed of the car  3  from the car speed calculating circuit  207 , and information on the position of the car  3  from the car position correcting circuit  208 . 
       FIG. 32  is a schematic diagram showing the rail joint detecting device  205  of  FIG. 31 . Referring to  FIG. 32 , the rail joint detecting device  205  has a sensor head  210  serving as a joint detecting portion for optically detecting the presence of the joint  202 , and a determination circuit  211  serving as a joint determining portion for determining the presence/absence of the joint  202  based on information from the sensor head  210 . The determination circuit  211  is electrically connected to the car position correcting circuit  208  ( FIG. 31 ). 
     The sensor head  210  is opposed to the car guide rail  2 . Further, the sensor head  210  has a light projecting portion (light source)  212  for irradiating light (light beam) having rectilinear property to the surface of the car guide rail  2 , and a light receiving portion  213  for receiving reflected light from the car guide rail  2  and converting it into an electrical signal (light reception signal) corresponding to the amount of received light. It should be noted that as the light projecting portion  212 , for example, a laser light irradiation device, a light source device combining a light emitting diode and a lens, or the like may be used. Further, as the light receiving portion  213 , for example, a photodiode, a CCD camera, a photomultiplier tube, or the like may be used. 
     The light projecting portion  212  is placed so as to irradiate light in an oblique direction with respect to the surface of the car guide rail  2 . That is, the light projecting portion  212  is placed such that the incident angle (the angle formed between the line perpendicular to the surface of the car guide rail  2  and the optical path of incident light) of the light irradiated from the light projecting portion  212  on the surface of the car guide rail  2  becomes a predetermined angle larger than 0 degree but smaller than 90 degrees. 
     The light receiving portion  213  is placed so as to avoid interference with the optical path of reflected light (specularly reflected light) due to such reflection that the incident and reflection angles of the light from the light projecting portion  212  on the surface of the car guide rail  2  become the same, that is, specular reflection. That is, the light receiving portion  213  is placed so as to avoid interference with the direction in which the reflected light of the light from the light projecting portion  212  as specularly reflected by the surface of the car guide rail  2  travels. It should be noted that the reflection angle refers to the angle formed between the line perpendicular to the surface of the car guide rail  2  and the optical path of the reflected light. 
     Here, processing is performed on the surface of each unit rail  201  so as to ensure that the light irradiated from the light projecting portion  212  undergoes substantially specular reflection. Since no such processing as that performed on the surface of each unit rail  201  is performed on the joint  202  between each of the unit rails  201 , the light irradiated from the light projecting portion  212  is scattered when reflected by each joint  202 . That is, when the light from the light projecting portion  212  is irradiated to the surface of each unit rail  202 , the light undergoes substantially specular reflection and does not directly enter the light receiving portion  213 , so the amount of light received by the light receiving portion  213  decreases; when the light from the light projecting portion  212  is irradiated to each joint  202 , the light is scattered by the joint  202 , so the amount of light received by the light receiving portion  213  increases. 
     Determination criteria for determining the presence/absence of the joint  202  is set in the determination circuit  211 . The determination circuit  211  determines that there has been no detection of the joint  202  (“joint not-present” determination) when the amount of light received by the light receiving portion  213  is equal to or lower in value than the determination criteria, and determines that the joint  202  has been detected (“joint present” determination) when the amount of light received by the light receiving portion  213  exceeds the determination criteria in value. Further, the determination circuit  211  is adapted to output information on the presence/absence of the joint  202  as obtained by the above determination to the car position correcting circuit  208 . Otherwise, Embodiment 17 is of the same construction as Embodiment 11. 
     Next, operation will be described. When a rotational position signal from the encoder  204  is inputted to the car position calculating circuit  206 , the position of the car  3  is obtained by the car position calculating circuit  206 . Thereafter, information on the position of the car  3  is outputted from the car position calculating circuit  206  to the car speed calculating circuit  207  and to the car position correcting circuit  208 . 
     In the car speed calculating circuit  207 , the speed of the car  3  is obtained based on the information on the position of the car  3 . Then, information on the speed of the car  3  obtained by the car speed calculating circuit  207  is outputted to the control device  209 . 
     Further, the car position correcting circuit  208  is constantly inputted with, separately from information on the position of the car  3  from the car position calculating circuit  206 , information on the presence/absence of the joint  202  which is obtained from the rail joint detecting device  205 . When there has been no detection of the joint  202  by the rail joint detecting device  205 , the car position correcting circuit  208  outputs to the control device  209  the information on the position of the car  3  from the car position calculating circuit  206 . 
     When the presence of the joint  202  is detected by the rail joint detecting device  205 , the car position correcting circuit  208  obtains the position of the car  3  based on the detection of the joint  202 . Then, the position of the car  3  thus obtained and the information on the position of the car  3  from the car position calculating circuit  206  are compared with each other. When the result of the comparison indicates that the respective pieces of position information on the car  3  match each other, the matched position information on the car  3  is outputted to the control device  209 , and when the respective pieces of position information differ from each other, the information on the position of the car  3  as obtained based on the detection of the joint  202  is outputted to the control device  209 . 
     Thereafter, the operation of the elevator is controlled on the basis of the information on the speed of the car  3  from the car speed calculating circuit  207  and the information on the position of the car  3  from the car position correcting circuit  208 . 
     That is, when the speed of the car  3  is substantially the same in value as the normal speed detection pattern  115  ( FIG. 19 ), the operation of the elevator is set to normal operation by the control device  209 . 
     For example, when, due to some cause, the speed of the car  3  increases abnormally and exceeds the first abnormal speed detection pattern  116  ( FIG. 19 ), an actuation signal and a stop signal are outputted to the hoisting machine braking device  106  ( FIG. 18 ) and to the hoisting machine  101  ( FIG. 18 ), respectively, from the control device  209 . As a result, the hoisting machine  101  is stopped, and the hoisting machine braking device  106  is actuated, thereby braking the rotation of the drive sheave  104 . 
     When, after the actuation of the hoisting machine braking device  106 , the speed of the car  3  further increases and exceeds the second abnormal speed detection pattern  117  ( FIG. 19 ), the control device  209  outputs an actuation signal to the safety device  33  ( FIG. 18 ) while continuing to output the actuation signal to the hoisting machine braking device  106 . As a result, the safety device  33  is actuated, thereby braking the car  3  through the same operation as that of Embodiment 2. 
     In the elevator rail joint detecting device  205  as described above, the sensor head  210  for detecting the presence of the joint  202  is provided to the car  3 , and the presence/absence of the joint  202  is determined by the determination circuit  211  based on information from the sensor head  210 . Accordingly, the sensor head  210  and the determination circuit  211  can be easily mounted to the car  3 , thereby facilitating the installation thereof in the elevator. Further, the joint  202  of the car guide rail  2  is detected, whereby the position of the car  3  can be easily detected with enhanced reliability without machining on a structure such as the car guide rail  2 . 
     Further, the sensor head  210  has the light projecting portion  212 , and the light receiving portion  213  for receiving the light from the light projecting portion  212  as reflected by the car guide rail  2 , with the light receiving portion  213  being placed so as to avoid interference with the optical path of the reflected light as specularly reflected by the surface of the car guide rail  2 . Accordingly, only the light scattered by the joint  202  can be received by the light receiving portion  213 , thereby making it possible to detect the presence of the joint  202  with enhanced reliability. 
     Further, in the elevator apparatus as described above, the position information on the car  3  from the car position calculating circuit  206  is corrected by the car position correcting circuit  208  based on information from the determination circuit  211  that determines the presence/absence of the joint  202 , and the operation of the elevator is controlled by the control device  209  based on the position information on the car  3  thus corrected. Accordingly, it is possible to prevent a large deviation from occurring between the position information on the car  3  that is inputted to the control device  209  and the actual position of the car  3 , whereby the operation of the elevator can be controlled with enhanced accuracy. Therefore, it is also possible to prevent, for example, collision or the like of the car  3  against an end portion of the hoistway  1 . Further, the vertical length of the hoistway  1  can also be reduced. 
     Embodiment 18 
       FIG. 33  is a schematic diagram showing an elevator rail joint detecting device according to Embodiment 18 of the present invention. Referring to  FIG. 33 , the light projecting portion  212  is adapted to irradiate light in a direction perpendicular to the surface of the car guide rail  2 . That is, the light projecting portion  212  is placed such that the incident angle of the light irradiated from the light projecting portion  212  on the surface of the car guide rail  2  becomes zero degree. It should be noted that oil  221  adheres to the surface of the car guide rail  2 . Otherwise, Embodiment 18 is of the same construction and operation as Embodiment 17. 
     In the elevator rail joint detecting device as described above, the light projecting portion  212  irradiates light in the direction perpendicular to the surface of the car guide rail  2 . Accordingly, even when a liquid such as the oil  221  adheres to the surface of the car guide rail  2 , it is possible to suppress the reflection of light by the surface of the oil  221 , thereby enhancing the efficiency of light reception by the light receiving portion  213 . 
     Embodiment 19 
       FIG. 34  is a schematic diagram showing an elevator rail joint detecting device according to Embodiment 19 of the present invention. Referring to  FIG. 34 , the polarization direction of light irradiated from the light projecting portion  212  is P-polarization. Here, in the case where light is reflected on the surface (plane) of the oil  221 , the polarization in the direction parallel to the plane containing the incident and reflected light beams, that is, the incidence plane, is referred to as the P-polarization. 
     Further, the light projecting portion  212  is adapted to irradiate light such that the incident angle of light on the surface of the car guide rail  2  becomes a Brewster angle. A Brewster angle refers to an incident angle at which the reflectance of the P-polarization becomes zero. A Brewster angle α is determined by a refractive index of an incident-side medium (which, in this example, is a refractive index of air) n 1 , and a refractive index of a refraction-side medium (which, in this example, is a refractive index of the oil  221 ) n 2 . That is, the relationship among the refractive index of air n 1 , the refractive index n 2  of the oil  221 , and the Brewster angle α can be represented by the following expression (1).
 
tan α= n 2 /n 1  (1)
 
     Otherwise, Embodiment 19 is of the same construction and operation as Embodiment 17. 
     In the elevator rail joint detecting device as described above, the polarization direction of light irradiated from the light projecting portion  212  is P-polarization, and the incident angle of the light on the surface of the car guide rail  2  is set to the Brewster angle, so even when the oil  221  adheres to the surface of the car guide rail  2 , the reflectance of light by the surface of the oil  221  can be made close to zero, thereby making it possible to further enhance the efficiency of light reception by the light receiving portion  213 . 
     Embodiment 20 
       FIG. 35  is a schematic diagram showing an elevator rail joint detecting device according to Embodiment 20 of the present invention. Referring to  FIG. 35 , a sensor head  225  has: a light projecting portion  226  for irradiating a plurality of (in this example, two) mutually parallel light beams A, B to the surface of the car guide rail  2 ; a plurality of (in this example, two) light receiving portions  227 ,  228  placed so as to avoid interference with the optical path of the light beams of the respective light beams A, B as specularly reflected by the car guide rail  2 , for receiving the light beams respectively reflected by the car guide  2 ; and an imaging optical system  230  including a lens  229  for imaging the respective reflected light beams to the respective light receiving portions  227 ,  228 . 
     The light projecting portion  226  is adapted to irradiate the light beam A and the light beam B to different positions of the car guide rail  2  with respect to the vertical direction. 
     The light receiving portion  227  receives a part of the reflected light beam of the light beam A irradiated to the joint  202 . Further, the light receiving portion  228  receives a part of the reflected light beam of the light beam B irradiated to the joint  202 . The light receiving portions  227 ,  228  each output to the determination circuit  211  an electrical signal (light reception signal) corresponding to the amount of received light. 
     The imaging optical system  230  images to the position of the light receiving portion  227  a part of the reflected light beam of the light beam A irradiated to the joint  202 , and images to the position of the light receiving portion  228  a part of the reflected light beam of the light beam B irradiated to the joint  202 . Accordingly, the light receiving portion  227  can receive only the reflected light beam of the light beam A, and the light receiving portion  228  can receive only the reflected light beam of the light beam B. Otherwise, Embodiment 20 is of the same construction and operation as Embodiment 17. 
     In the elevator rail joint detecting device as described above, the sensor head  225  has the two light receiving portions  227 ,  228 , and the detection of the presence/absence of the joint  202  is performed based on the amounts of the reflected light beams respectively received by the light receiving portions  227 ,  228 , thereby achieving enhanced reliability of the detection of the joint  202 . Accordingly, it is possible to reduce detection omission of the joint  202 , whereby the joint  202  can be detected with enhanced reliability. 
     It should be noted that, while in the above-described example the reflected light beams of the two light beams irradiated from the light projecting portions  226  are respectively received by the two light receiving portions  227 ,  228 , the number of light beams irradiated from the light projecting portion  212  may be set to three or more, the reflected light beams of the respective light beams being received by the same number of light receiving portions as the number of the irradiated light beams, that is, three or more light receiving portions. 
     Further, while in the above-described example the respective light beams are irradiated in the direction perpendicular to the surface of the car guide rail  2 , it is also possible, as in Embodiment 19, to set the incident angle of each light beam on the car guide rail  2  to the Brewster angle. 
     Further, while in each of Embodiments 17 through 20 the rail joint detecting device for detecting the presence/absence of a joint of the car guide rail is applied to the elevator apparatus according to Embodiment 11, the rail joint detecting device may be mounted to the car  3  of the elevator apparatus according to each of Embodiments 1 through 10 and 12 through 16 to detect the presence/absence of a rail joint of the car guide rail  2 . In this case, the operation of the elevator is controlled by an output portion as the control device based on information from the rail joint detecting device. 
     Further, while in each of Embodiments 1 through 20 described above the safety device applies braking with respect to an overspeed (movement) of the car in the downward direction, the safety device may be mounted upside down to the car to thereby apply braking with respect to an overspeed (movement) in the upward direction.