Abstract:
The present invention relates to a locking device which has an electromagnet solenoid, and more particularly to a locking device which has an electromagnet solenoid, and which is suitably used in a shift lever lock in a vehicle automatic transmission apparatus. In the present invention the attraction type solenoid is used for controlling the operations of the movable members of the locking device. A locking device is provided in which the movable members of the locking device can be smoothly operated without hindrance, locking and unlocking operations of the locking device are highly reliable, and a harsh operation noise can be prevented by a shock-absorbing member from being produced, and which is simple and compact in configuration, and economical.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The present invention relates to a locking device which has an electromagnet solenoid, and more particularly to a locking device which has an electromagnet solenoid, and which is suitably used in a shift lever lock in a vehicle automatic transmission apparatus.  
         [0003]     2. Description of the Prior Art  
         [0004]     In order that a vehicle (AT vehicle) on which an automatic transmission apparatus is mounted is prevented from being suddenly started as a result of an erroneous operation in which a shift lever is accidentally shifted from a parking range position to another range position, conventionally, a locking device with an electromagnet solenoid has been proposed (for example, Japanese Patent Application Laying-Open No. 2005-47406). The locking device is used in a shift lever lock for a vehicle automatic transmission apparatus in which, when the shift lever is located at the parking range position, the shift lever is locked so that an shift operation to another range position is restricted, and, in accordance with a depressing operation on an foot brake, the shift lever lock is cancelled and an shift operation to another range position is allowed.  
       SUMMARY OF THE INVENTION  
       [0005]     In the conventional locking device, since a suction type solenoid is used, an urging member which laterally compresses a locking member disposed integrally with a movable core cannot be placed in a middle portion of the locking member (the urging member is placed above or under the solenoid). When the movable core is sucked to or separated from a stationary core, therefore, a rotary moment acts on the movable core and the locking member. Consequently, the movable core and the locking member are tilted, and a prying phenomenon may occur, thereby causing a problem in that such a locking device has low operation reliability. Furthermore, the suction type solenoid has a problem in that the surface state (the inclination of a suction face, adhesion of a foreign matter, rust, and the like) of the movable core largely affects the suction force, and this causes a serious effect on the reliability of the locking device. The suction type solenoid has a further problem in that a harsh operation noise (a sound of a collision between metals) is produced at the instant when the movable core is sucked to the stationary core.  
         [0006]     In order to solve the problems of the conventional art, the invention provides a locking device wherein the locking device comprises: a first movable member which is reciprocable between an engaging position with respect to an external mechanism and a disengaging position; a first urging member which always urges the first movable member toward the engaging position; a second movable member which is reciprocable in a direction perpendicular to the first movable member between a locking position where one end portion overlaps with an operation region end portion in a disengaging direction of the first movable member, and a unlocking position where the one end portion deviates from the operation region end portion; a second urging member which always urges the second movable member toward the locking position; and a solenoid in which a stationary core in a coil is magnetized by energization of the coil to attract a movable plate swingably attached to a frame by an attraction force acting between the stationary core and the movable plate, from a separating position which is separated from the stationary core by a constant distance, toward the stationary core, a tip end portion of the movable plate of the solenoid is engaged with the second movable member, and, in a nonenergization period of the coil of the solenoid, by an urging force of the second urging member, the second movable member is held to the locking position and the movable plate of the solenoid is held to the separating position, the second movable member at the locking position restricts an operation of the first movable member from the engaging position to the disengaging position, and, in an energization period of the coil of the solenoid, by the attraction force acting between the stationary core and the movable plate, the movable plate of the solenoid is attracted against the urging force of the second urging member from the separating position toward the stationary core and the second movable member is operated from the locking position toward the unlocking position, thereby allowing the first movable member to be operated from the engaging position to the disengaging position.  
         [0007]     In the invention, a solenoid of the attraction type (also called the fulcrum type, the flapper type, or the magnet type) is used, and hence an operation of the second movable member is conducted not by a suction force of the movable plate, but by the attraction force. Therefore, the operation of the second movable member is not affected by the surface state of the movable plate, with the result that the operation of the second movable member in the locking device is stabilized and the reliability is improved.  
         [0008]     Since the attraction type solenoid is used and the tip end portion of the movable plate is engaged with the second movable member which is separated and independent from the movable plate, the second urging member can be placed in a middle portion of the second movable member. In locking and unlocking, therefore, the prying phenomenon is not caused in the operation of the second movable member, and the operation is stabilized. Consequently, the reliability of the locking device is enhanced.  
         [0009]     Since the attraction type solenoid is used, a shock-absorbing member can be disposed on the surface of the stationary core to which the movable plate is to be attracted, so that a harsh operation noise is not produced.  
         [0010]     In the invention, preferably, a tapered face is disposed in an end portion of the first movable member which is to be engaged with the external mechanism, the tapered face being slidingly contacted with the external mechanism in one direction to cause the first movable member to operate against the urging force of the first urging member from the engaging position toward the disengaging position, the locking device further comprises: a third movable member which is engaged with the first movable member, and which is operable independent from the first movable member; and a third urging member which always urges the third movable member in a same direction as the first movable member, a tapered face is disposed in an end portion of the third movable member which is located on a side of the end portion of the first movable member which is to be engaged with the external mechanism, the tapered face being slidingly contacted with the external mechanism in advance of the tapered face of the first movable member, to cause the third movable member to independently operate against an urging force of the third urging member in advance of the first movable member, a movable-plate pressing portion is disposed in another end portion of the third movable member, and the independent operation of the third movable member causes the movable plate of the solenoid to be pressed against the urging force of the second urging member from the separating position toward the stationary core, and the second movable member to be operated from the locking position toward the unlocking position, thereby allowing the first movable member to be operated from the engaging position to the disengaging position. When this configuration is employed, an unlocking operation in one direction can be conducted mechanically without using an electric power source.  
         [0011]     In the invention, in the case where the external mechanism is a shift lever mechanism for a vehicle automatic transmission apparatus, preferably, energization of the coil of the solenoid is conducted in accordance with a depressing operation on an foot brake, and, in a nonenergization period of the coil of the solenoid when the foot brake is not depressed, the first movable member in which an operation from the engaging position to the disengaging position is restricted restricts an shift operation of the shift lever from a predetermined range position to another range position, and, in an energization period of the coil of the solenoid in accordance with a depressing operation on the foot brake, an operation of the first movable member from the engaging position to the disengaging position is allowed, and an shift operation of the shift lever from the predetermined range position to another range position is allowed. When this configuration is employed, the locking device can be suitably used as a shift lever locking device for a vehicle automatic transmission apparatus. In this case, it is preferable to configure the locking device so that, in accordance with an shift operation of the shift lever from another range position to the predetermined range position, the third movable member is independently operated, thereby allowing an operation of the first movable member from the engaging position to the disengaging position. When this configuration is employed, in accordance with a shift operation of the shift lever from another range position to the predetermined range position, an unlocking operation can be conducted mechanically without using an electric power source.  
       EFFECTS OF THE INVENTION  
       [0012]     According to the invention, since an attraction type solenoid is used, it is possible to provide a locking device in which movable members of the locking device can be smoothly operated without hindrance, locking and unlocking operations of the locking device are highly reliable, and a harsh operation noise can be prevented by a shock-absorbing member from being produced, and which is simple and compact in configuration, and economical. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0013]      FIG. 1  is a diagram showing the internal structure of a shift lever locking device for a vehicle automatic transmission apparatus according to an embodiment of the invention;  
         [0014]      FIG. 2  is a plan view of the locking device;  
         [0015]      FIG. 3  is an operation diagram of the locking device;  
         [0016]      FIG. 4  is a diagram schematically illustrating a shift lever mechanism of the vehicle automatic transmission apparatus which is an external mechanism of the locking device; and  
         [0017]      FIG. 5  is a diagram of a locking device of a modification. 
     1  case      10  attraction type solenoid      11  frame (yoke)      12  stationary core      14  coil      15  fulcrum      16  movable plate      17  shock-absorbing member      20  stopper (second movable member)      30  main lever (first movable member)      38  tapered face      40  sublever (third movable member)      42  tapered face      43  movable-plate pressing portion      50  second return spring (second urging member)      60  first return spring (first urging member)      70  third return spring (third urging member)      100  shift lever mechanism (external mechanism)      103  shift lever     
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0037]     Hereinafter, an embodiment of the invention will be described with reference to the accompanying drawings.  FIG. 1  is a diagram showing the internal structure of a shift lever locking device for a vehicle automatic transmission apparatus according to the embodiment of the invention,  FIG. 2  is a plan view of the locking device,  FIG. 3  is an operation diagram of the locking device, and  FIG. 4  is a diagram schematically illustrating a shift lever mechanism of the vehicle automatic transmission apparatus which is an external mechanism of the locking device.  
         [0038]     First, the shift lever mechanism of the vehicle automatic transmission apparatus which is the external mechanism of the locking device will be described with reference to  FIG. 4 . In  FIG. 4, 100  denotes the straight type shift lever mechanism (shift operation unit) which is placed in the vicinity of the driver&#39;s seat, for example, between the driver&#39;s seat and the front passenger seat, and which is configured by attaching various components to a frame body  101  made of a resin. The reference numeral  102  denotes a lever guide plate which is attached to an upper portion of the frame body  101 , and the surface of which is exposed to the interior of the cabin, and  103  denotes a shift lever in which a lower end portion is swingably attached to the frame body  101  via a fulcrum shaft  104 , and an upper portion is elongated into the cabin via a straight type lever guide groove  105  disposed in the lever guide plate  102 . By pressing or pulling an upper handle  106 , the shift lever  103  is shift-operated to one of range positions including a parking range position (P-range) which is set in one end portion of the lever guide groove  105 , and other range positions which are sequentially set subsequent to the parking range position, such as a reverse range position (R-range), a neutral range position (N-range), a drive range position (D-range), and a low range position (L-range). In the shift lever  103 , a select button  107  is disposed on the upper handle  106 , and a shift lock pin  108  is disposed so as to be movable in a predetermined range along the lever axis. The shift lock pin  108  is always urged by a spring force toward the upper end of the shift lever  103 . When the select button  107  is operated, the shift lever  103  can be compulsively pressed down toward the lower end of the shift lever  103  against the spring force. The reference numeral  109  denotes a shift lock groove which is opened in the frame body  101  along the lever axis of the shift lever  103  that is positioned in the P-range. The shift lock pin  108  is fitted into the shift lock groove  109 . One end of an arcuate guide groove  110  which is opened in the frame body  101  in the shift operation range of the shift lever  103  and on the circumference centered at the fulcrum shaft  104  is connected substantially perpendicularly and communicatingly to a lower end portion of the shift lock groove  109 .  
         [0039]     In the above configuration, when the shift lever  103  is positioned at the P-range, the select button  107  is operated so as to compulsively press down the shift lock pin  108  to a lower end portion of the shift lock groove  109  against the spring force, and then move the pin to a beginning portion of the guide groove  110 , whereby a shift operation from the P-range position to another range position is enabled.  
         [0040]     The locking device is placed in the shift lever mechanism  100  in a state where a case (housing)  1  formed in a rectangular parallelepiped shape is attached by two screws  4 ,  4  to the lower side of the guide groove  110  in the frame body  101 , and tip and portions (upper end portions) of a main lever  30  serving as the first movable member, and a sublever  40  serving as the third movable member which are upward projected from a right side portion of an upper side wall of the case  1  to the outside of the case  1  are raised from the lower side at a right lateral position of a lower end portion of the shift lock groove  109 .  
         [0041]     In the above configuration, when the shift lever  103  is positioned at the P-range and the select button  107  is operated, the shift lock pin  108  butts from the upper side against the tip end face of the main lever  30  of the locking device in front of the lower end portion of the shift lock groove  109 . By contrast, when the shift lever  103  is shift-operated from a range position other than the P-range to the P-range position, the shift lock pin  108  butts from a lateral side against side faces of the sublever  40  and the main lever  30  of the locking device in the beginning portion of the guide groove  110 .  
         [0042]     Next, the locking device will be described with reference to  FIGS. 1 and 2 . The locking device comprises the case  1  formed in a rectangular parallelepiped shape. The case  1  is configured by a first case  2  which is made of a resin material, and which is deep, and a second case  3  which is joined to the first case  2 , and which is shallow. Flanges  6  having screw holes  5  through which the screws  4  are passed in the joining direction are disposed integrally with outer faces of right and left side walls of the first and second cases  2 ,  3 . In an end face of the first case  2  which is joined to the second case  3 , disposed are a first recess  7  for forming a lever projection port through which upper end portions (end portions to be engaged with the shift lock pin  108 ) of the main lever  30  and the sublever  40  are upward projected from the right side portion of the upper side wall of the case  1  to the outside of the case  1 , and a second recess  8  for forming a lead wire port through which two lead wires  14   a,    14   b  drawn out from a coil  14  of a solenoid  10  are further drawn out from the left side wall of the case  1  to the outside of the case  1 .  
         [0043]     The locking device further comprises: the solenoid  10 ; a stopper  20  which is made of a resin material, and which serves as the second movable member; the main lever  30  which serves as the first movable member; the sublever  40  which serves as the third movable member; a second return spring  50  which is configured by a coil spring, and which serves as the second urging member for the stopper; a first return spring  60  which is configured by a coil spring, and which serves as the first urging member for the main lever; and a third return spring  70  which is configured by a coil spring, and which serves as the third urging member for the sublever.  
         [0044]     The solenoid  10  of the locking device is placed in a left upper corner of the interior of the case  1  on the side of the first case  2 . The solenoid  10  is configured as the suction type by: a hook-shaped frame (yoke)  11  which is made of a magnetic material, and which is bent at right angle so as to extend along inner walls of left and upper side walls of the first case  2 ; a columnar stationary core  12  which is made of a magnetic material, which is projected in a cantilevered manner in parallel to a horizontal piece  11   b  b of the frame  11  extending along the upper-wall inner face of the first case  2 , from a substantially middle portion of a vertical piece  11   a  of the frame  11  extending along the left-wall inner face of the first case  2 , and which is placed in a horizontal posture in which the axis is laterally directed, in a substantially vertically middle portion of a left-half portion of the interior of the first case  2 ; the coil  14  which is configured by winding an insulated copper wire or the like around a bobbin  13  made of an insulating material, and which is concentrically placed on the outer circumference of the stationary core  12 ; and a movable plate  16  which is made of a magnetic material, in which an upper end portion is engaged with a tip end portion of the horizontal piece  11   b  of the frame  11  by a hinge structure, to function as a fulcrum  15 , and which is hangingly supported from the tip end portion of the horizontal piece  11   b  of the frame  11  on the right side of the stationary core  12  and the coil  14  via the fulcrum  15 , and placed so as to be swingable in lateral directions contacted with and separated from the stationary core  12  in a substantially laterally middle portion of the interior of the first case  2 . In the attraction type solenoid  10 , the stationary core  12  in the coil  14  is magnetized by energizing the coil  14  to conduct an operation of attracting the movable plate  16  which is separated from the stationary core  12  by a constant distance (stroke), toward the stationary core  12  by an attraction force which acts between the stationary core  12  and the movable plate  16 . In the attraction type solenoid  10 , a shock-absorbing member  17  configured by a thin rubber plate is bonded to the surface (tip end face) of the stationary core  12  to which the movable plate  16  is to be attracted. The shock-absorbing member  17  can prevent a harsh operation noise (metallic sound of collision of the movable plate  16  against the stationary core  12 ) from being generated. The two lead wires  14   a,    14   b  drawn out from the coil  14  are further drawn out from the left side wall of the case  1  to the outside of the case  1  through a recess  18  disposed in a corner portion of one side end face of the frame  11  on the side of the second case  3 , and the second recess  8  of the first case  2 . The coil  14  of the attraction type solenoid  10  is energized in accordance with a depressing operation on a foot brake when an ignition key of the vehicle is turned on, and is not energized when the foot brake is not depressed.  
         [0045]     The stopper  20  which serves as the second movable member is formed into a quadrangular prism-like shape, and placed under the attraction type solenoid  10  on the side of the first case  2  in the interior of the case  1 , and in a horizontal posture in which the axis is laterally directed.  
         [0046]     The stopper is disposed so as to be laterally reciprocable along the inner face of the lower side wall of the first case  2 . Between the stopper  20  and the left side wall of the first case  2 , the second return spring  50  is disposed in a compressed state coaxially with the axis of the stopper  20 , to always urge the stopper  20  in the rightward direction. In the stopper  20 , an engagement groove  21  is disposed in a substantially middle portion in the longitudinal direction in one side face on the side of the second case  3 , and a tip end portion of the movable plate  16  of the attraction type solenoid  10  is inserted from the upper side into the engagement groove  21  to be engaged therewith.  
         [0047]     In the above configuration, in a nonenergization period of the coil  14  of the attraction type solenoid  10 , an attraction force is not generated between the stationary core  12  and the movable plate  16 . As indicated by the solid lines in  FIG. 1 , the stopper  20  is held by the urging force of the second return spring  50  to a position (locking position) where the stopper butts against the right side wall of the first case  2 , and the movable plate  16  whose tip end portion is engaged with the stopper  20  is held to a separating position which is separated from the stationary core  12  by a constant distance (stroke). When the coil  14  of the attraction type solenoid  10  is energized, an attraction force is generated between the stationary core  12  and the movable plate  16 . Therefore, the movable plate  16  which is at the separating position is attracted toward the stationary core  12 , and leftward swung until the plate is closely contacted with the shock-absorbing member  17  disposed on the tip end face of the stationary core  12 , while the stopper  20  engaged with the tip end portion of the movable plate  16  is leftward linearly operated from the locking position against the urging force of the second return spring  50 . When the energization of the coil  14  of the attraction type solenoid  10  is continued, as indicated by the phantom lines in  FIG. 1 , the attraction force generated between the stationary core  12  and the movable plate  16  holds the movable plate  16  in the state where the plate is closely contacted with the shock-absorbing member  17  disposed on the tip end face of the stationary core  12 , and holds the stopper  20  engaged with the tip end portion of the movable plate  16  against the urging force of the second return spring  50  to a separating position (unlocking position) which is separated by a constant distance from the right side wall of the first case  2 . By contrast, when the energization of the coil  14  of the attraction type solenoid  10  is turned off, the attraction force generated between the stationary core  12  and the movable plate  16  disappears. By the urging force of the second return spring  50 , therefore, the stopper  20  is rightward linearly operated from the unlocking position, and returned and held to the original locking position. The movable plate  16  whose tip end portion is engaged with the stopper  20  is rightward swung in accordance with the returning operation of the stopper  20  to the locking position, to be separated by the constant distance from the stationary core  12 , and returned and held to the original separating position.  
         [0048]     The main lever  30  which serves as the first movable member is configured by: a first engagement portion  31  having a quadrangular prism-like shape; and a plate-like second engagement portion  33  which is thinner than the first engagement portion  31 , and which has three side faces that are flush with three side faces of the first engagement portion  31 , and one side face that is continuous to the remaining one face of the first engagement portion  31  via a stepped face (one end face of the first engagement portion  31 )  32 . The main lever  30  is placed inside the case  1  on the right side of the attraction type solenoid  10  on the side of the first case  2  in a vertical posture which is perpendicular to the stopper  20 , in a state where the stepped one side face (left side face) is directed toward the attraction type solenoid  10 , the flush right side face is contacted with the inner face of the right side wall of the first case  2 , the first engagement portion  31  is located in the upper side, and the second engagement portion  33  is located in the lower side. The main lever  30  is disposed so as to be vertically reciprocable along the inner face of the right side wall of the first case  2 . The main lever  30  is formed so as to have an approximately same length as the height of the external shape of the case  1 . In order to set the operation region (to restrict the operation range) of the main lever  30  between the two side faces adjacent to the left side face of the first engagement portion  31  opposed to the attraction type solenoid  10 , and the faces on the sides of the first and second cases  2 ,  3  with which the two side faces are slidingly contacted, a rectangular bottomed guide groove  34  having a predetermined vertical length is disposed in the two side faces adjacent to the left side face of the first engagement portion  31  opposed to the attraction type solenoid  10 , and a flat rectangular guide projection  35  which is slidably fitted into the bottomed guide groove  34  is disposed integrally with the faces on the sides of the first and second cases  2 ,  3  with which the two side faces adjacent to the left side face of the first engagement portion  31  opposed to the attraction type solenoid  10  are slidingly contacted. In the case  1 , the main lever  30  is disposed so as to be overridable on the stopper  20  in the locking position, and to be reciprocable vertically and linearly between: the maximum raised position (engaging position with the shift lock pin  108 ) where the lower end of the main lever  30  (the tip end of the second engagement portion  33 ) is raised to a substantially same level as the upper side face of the stopper  20 , and an upper end portion of the main lever  30  (a tip end portion of the first engagement portion  31 ) is projected by a predetermined projection length H 1  from a right side portion of the upper side wall of the case  1  via the lever projection port formed by the first recess  7  of the first case  2  to the outside of the case  1 ; and the maximum lowered position (disengaging position with the shift lock pin  108 ) where, in the case  1 , the lower end of the main lever  30  is lowered more than the upper side face of the stopper  20 , and the upper end portion of the main lever  30  is projected by a predetermined projection length H 2  which is shorter than the projection length H 1  at the engaging position from a right side portion of the upper side wall of the case  1  via the lever projection port formed by the first recess  7  of the first case  2  to the outside of the case  1  (the upper end portion of the main lever  30  which is projected from the right side portion of the upper side wall of the case  1  via the lever projection port formed by the first recess  7  of the first case  2  to the outside of the case  1  is retracted into the case  1  so as to have the predetermined projection length H 2  which is shorter than the projection length H 1  at the engaging position). The projection lengths H 1 , H 2  of the upper end portion of the main lever  30  are set so that, as indicated by the solid lines in  FIG. 4 , the longer length H 1  is set to a value which restricts the passing of the shift lock pin  108  from the lower end portion of the shift lock groove  109  to the beginning portion of the guide groove  110 , or the passing from the beginning portion of the guide groove  110  to the lower end portion of the shift lock groove  109 , and, as indicated by the phantom lines in  FIG. 4 , the shorter length H 2  is set to a value which allows the passing of the shift lock pin  108  from the lower end portion of the shift lock groove  109  to the guide groove  110 , or the passing from the beginning portion of the guide groove  110  to the lower end portion of the shift lock groove  109 . The projection length H 2  of the upper end portion of the main lever  30  may be “ 0 ”. Inside the second engagement portion  33  of the main lever  30 , the first return spring  60  is disposed in a compressed state to always urge the main lever  30  in the upward direction, between the first engagement portion  31 , and a spring seat  36  which is projected integrally from the first case  2  at a position that is opposed to the stepped face  32 , that is lower than the lower end of the first engagement portion  31 , i.e., the stepped face  32 , and that is higher than the stopper  20 . The horizontal lower face of the spring seat  36  cooperates with the inner lower side face of the first case  2  to sandwich the stopper  20  therebetween so as to be laterally slidable, thereby enabling the spring seat to function also as a slide guide for the stopper  20 . The vertical right end face of the spring seat  36  cooperates with the inner right side face of the first case to sandwich the second engagement portion  33  of the main lever  30  therebetween so as to be vertically slidable, thereby enabling the spring seat to function also as a slide guide for the main lever  30 . Alternatively, with respect to the bottomed guide groove  34  and the guide projection  35  for setting the operation region of the main lever  30 , the bottomed guide groove  34  may be disposed on the side of the first and second cases  2 ,  3 , and the guide projection  35  may be disposed on the side of the main lever  30 .  
         [0049]     In the above configuration, an end portion on the locking side in the operation region between the locking and unlocking positions of the stopper  20 , and an end portion on the unlocking side in the operation region between the locking and unlocking positions of the main lever  30  overlap with each other in the right lower corner on the side of the first case  2  in the case  1 . Depending on the operation position of the stopper  20 , the operation region of the stopper is caused to overlap with, or separate from the operation region of the main lever  30 , thereby restriction or allowing the operation of the main lever  30  from the locking position to the unlocking position. In the nonenergization period of the coil  14  of the attraction type solenoid  10  in the state where the main lever  30  is held to the engaging position by the urging force of the first return spring  60 , the stopper  20  and the movable plate  16  are returned and held to the locking position and the separating position by the urging force of the second return spring  50 . As indicated by the solid lines in  FIG. 1 , therefore, the right end portion of the stopper  20  at the locking position is sandwiched between the lower end of the main lever  30  at the engaging position and the lower side walls of the first case  2 , and the main lever  30  at the engaging position overrides the right end portion of the stopper  20  at the locking position. The stopper  20  at the locking position restricts the operation of the main lever  30  from the engaging position to the disengaging position. The main lever  30  is fixed at the engaging position where the upper end portion is projected by the projection length H 1  from the right side portion of the upper side wall of the case  1  to the outside of the case  1  via the lever projection port formed by the first recess  7  of the first case  2 . When the coil  14  of the attraction type solenoid  10  is energized, the movable plate  16  and the stopper  20  are leftward operated toward the unlocking position by the attraction force generated between the stationary core  12  and the movable plate  16 . As indicated by the phantom lines in  FIG. 1 , therefore, the right end portion of the stopper  20  is separated from the position between the lower end of the main lever  30  at the engaging position and the lower side wall of the first case  2  to the left side, and a gap corresponding to the height of the stopper  20  is formed (an operation region corresponding to the height of the stopper  20  is formed under the main lever  30  at the engaging position), whereby the operation of the main lever  30  from the engaging position to the disengaging position is allowed, so that the main lever  30  can be operated to the disengaging position where the upper end portion is projected from the right side portion of the upper side wall of the case  1  via the lever projection port formed by the first recess  7  of the first case  2 , to the outside of the case  1  by the projection length H 2  (the upper end portion of the main lever  30  which is projected from the right side portion of the upper side wall of the case  1  via the lever projection port formed by the first recess  7  of the first case  2  to the outside of the case  1  is retractable into the case  1  so as to have the predetermined projection length H 2  which is shorter than the projection length H 1  at the engaging position).  
         [0050]     The sublever  40  is formed into a plate-like shape having an approximately same length as the first engagement portion  31  of the main lever  30 , and a flat head portion  41  is formed perpendicularly integrally on one end. In accordance with a shift operation of the shift lever  103  from a range position other than the P-range to the P-range position, the shift lock pin  108  which is moved in the guide groove  110  toward the beginning portion of the groove is engaged from a lateral side in the beginning portion of the guide groove  110  with one side face of the main lever  30 , i.e., one side face (left side face) of the first engagement portion  31  on the side the attraction type solenoid  10 . In the side face, a sublever attachment groove  37  is disposed with which an approximately half of the total width of the sublever  40  is vertically slidably fitted and engaged. In a state where the head portion  41  of the sublever  40  is opposed in underside to the stepped face  32  of the main lever  30 , and an approximately half of the total width of the sublever  40  is perpendicularly projected from a middle portion of the left side face of the main lever  30 , the sublever  40  is attached to the main lever  30  via the sublever attachment groove  37 . The third return spring  70  is disposed in a compressed state between the head portion  41  of the sublever  40  and the spring seat  36 , to always upward urge the sublever  40 , and to upward urge the main lever  30  via the head portion  41  of the sublever  40 . The urging force of the third return spring  70  is set to be larger than that of the first return spring  60 . In a state where the head portion  41  is buttingly engaged from the lower side with the stepped face  32  of the main lever  30  by the urging force of the third return spring  70 , the sublever  40  can be vertically reciprocated integrally with the main lever  30 , and can be vertically reciprocated independently from the main lever  30 . When the head portion  41  of the sublever  40  is buttingly engaged from the lower side with the stepped face  32  of the main lever  30 , the upper end of the sublever  40  coincides with that of the main lever  30 , and the upper end faces of the levers  30 ,  40  are flush with each other. In the main lever  30 , in order to, in accordance with a shift operation of the shift lever  103  from a range position other than the P-range to the P-range position, allow the main lever  30  to be pressed down from the engaging position to the disengaging position against the urging forces of the first and third return springs  60 ,  70  by the sliding contact with the shift lock pin  108  which is moved in the guide groove  110  toward the beginning portion of the groove, a left upper edge portion of the first engagement portion  31  is chamfered, and a tapered face  38  is disposed in an upper end portion of the left side face of the first engagement portion  31 . In the sublever  40 , in order to, in accordance with a shift operation of the shift lever  103  from a range position other than the P-range to the P-range position, allow the sublever  40  to be singly pressed down against the urging force of the third return spring  70  with respect to the main lever  30  at the engaging position in advance of the pressing down operation of the main lever  30  at the engaging position by the sliding contact with the shift lock pin  108  which is moved in the guide groove  110  toward the beginning portion of the groove, a left upper edge portion of the sublever  40  is chamfered in the same manner as the main lever  30 , and a tapered face  42  which is substantially parallel to the tapered face  38  of the main lever  30  is disposed in an upper end portion of the left side face of the sublever  40 . In the sublever  40 , a movable-plate pressing portion  43  which is projected from the left lower edge portion of the sublever  40  toward the movable plate  16  is integrally disposed in order that, in accordance with a single pressing down operation of the sublever  40  on the main lever  30  at the engaging position, in the nonenergization period of the coil  14  of the attraction type solenoid  10 , the sublever is slidingly contacted with the surface of the movable plate  16  which is returned and held to the separating position, the surface being on the side opposite to the stationary core  12 , and the movable plate  16  of the attraction type solenoid  10  is pressed against the stationary core  12  until the plate is closely contacted from the separating position with the shock-absorbing member  17  disposed on the tip end face of the stationary core  12  against the urging force of the second return spring  50 . A resin plate  44  which is made of the same material as the sublever  40  is bonded to the metal surface of the movable plate  16  with which the movable-plate pressing portion  43  made of a resin is slidingly contacted, in order to prevent the movable-plate pressing portion  43  from abrading, and to obtain a pressing force on the movable plate  16 . A lower edge portion of the tip end of the movable-plate pressing portion  43  is rounded (R), and the upper end of the resin plate  44  is tapered, so that the movable-plate pressing portion  43  can smoothly override the surface of the resin plate  44 . Preferably, an urging member  19  configured by a coil spring or a plate spring that always urges the movable plate  16  in a direction along which the plate is separated from the stationary core  12  is disposed in the attraction type solenoid  10 . The urging force of the urging member  19  is set to be smaller than that of the second return spring  50 . The movable plate  16  of the attraction type solenoid  10  is always contacted and held to the movable-plate pressing portion  43  of the sublever  40  by the urging force of the urging member  19 .  
         [0051]     In the above configuration, in a state where the main lever  30  is fixed at the engaging position and in a nonenergization period of the coil  14  of the attraction type solenoid  10 , the shift lock pin  108  which is moved in the guide groove  110  toward the beginning portion of the groove in accordance with a shift operation of the shift lever  103  from a range position other than the P-range to the P-range position is first contacted form the left side with the tapered face  42  of the sublever  40  in the beginning portion of the guide groove  110 , to rightward press the tapered face  42 , whereby the sublever  40  is singly pressed down against the urging force of the third return spring  70  with respect to the main lever  30  at the engaging position. In accordance with the single pressing down operation of the sublever  40  on the main lever  30  at the engaging position, the movable-plate pressing portion  43  disposed on the lower end of the sublever  40  presses the movable plate  16  of the attraction type solenoid  10  against the stationary core  12  until the plate is closely contacted from the separating position with the shock-absorbing member  17  disposed on the tip end face of the stationary core  12  against the urging force of the second return spring  50 . In the same manner as the energization period of the coil  14  of the attraction type solenoid  10 , therefore, a state where the operation of the main lever  30  from the engaging position to the disengaging position is allowed is produced (the unlocking operation is mechanically conducted). While pressing and holding the sublever  40 , thereafter, the shift lock pin  108  is slidingly contacted from the left side with the tapered face  38  of the main lever  30  to rightward press the tapered face  38 , whereby the main lever  30  in which the operation from the engaging position to the disengaging position is allowed is pressed down to the disengaging position against the urging force of the first return spring  60 .  
         [0052]     Referring to  FIG. 3 , the operation of the thus configured locking device will be described. For example, in the case where the select button  107  is operated to shift-operate the shift lever  103  located at the P-range to another range position, when the foot brake is not depressed, the coil  14  of the attraction type solenoid  10  of the locking device is not energized. In the nonenergization period of the coil  14  of the attraction type solenoid  10 , an attraction force is not generated between the stationary core  12  and the movable plate  16 . As shown in  FIG. 3 (A), therefore, the stopper  20  is held to the locking position by the urging force of the second return spring  50 , and the movable plate  16  of the attraction type solenoid  10  in which the tip end portion is engaged with the stopper  20  is held to the separating position. The operation of the main lever  30  from the engaging position to the disengaging position is restricted by the stopper  20  at the locking position. Therefore, the shift lock pin  108  is buttingly engaged before the lower end portion of the shift lock groove  109  from the upper side with the tip end face of the main lever  30  in which the operation from the engaging position to the disengaging position is restricted, and cannot be moved to the lower end portion of the shift lock groove  109 . Therefore, the shift lever  103  cannot be shift-operated from the P-range position to another range position, and is locked to the P-range position. The locking device is provided with the shift lever locking function.  
         [0053]     By contrast, when the foot brake is depressed, the coil  14  of the attraction type solenoid  10  of the locking device is energized in accordance with the operation of depressing the foot brake. In the energization period of the coil  14  of the attraction type solenoid  10 , an attraction force is generated between the stationary core  12  and the movable plate  16 . As shown in  FIG. 3 (B), by the attraction force generated between the stationary core  12  and the movable plate  16 , therefore, the movable plate  16  at the separating position is attracted toward the stationary core  12  against the urging force of the second return spring  50 , and the stopper  20  which is engaged with the tip end portion of the movable plate  16  is operated from the locking position to the unlocking position, thereby allowing the main lever  30  to be operated from the engaging position to the disengaging position. Therefore, the shift lock pin  108  is buttingly engaged before the lower end portion of the shift lock groove  109  from the upper side with the tip end face of the main lever  30  in which the operation from the engaging position to the disengaging position is restricted, and thereafter can be passed through the lower end portion of the shift lock groove  109  to be moved to the beginning portion of the guide groove  110  while pressing down the main lever  30  integrally with the sublever  40  to the disengaging position against the urging forces of the first and third return springs  60 ,  70 . As a result, the shift lever  103  can be shift-operated from the P-range position to another range position. The locking device is provided with the electrical shift lever unlocking function.  
         [0054]     After the shift lever  103  which is located at the P-range position is shift-operated to another range position such as the D-range position, the foot is lifted off the foot brake, and the accelerator lever is depressed to start the vehicle. In this case, in the state where the shift lock pin  108  is located in the guide groove  110 , the locking device is returned to the locked state shown in  FIG. 3 (A).  
         [0055]     When the shift lever  103  is shift-operated from a range position other than the P-range to the P-range position, the shift lock pin  108  which is moved in the guide groove  110  toward the beginning portion of the groove operates in the following manner in accordance with the shift operation. In the beginning portion of the guide groove  110 , as shown in  FIG. 3 (C), the sublever  40  is first singly pressed with respect to the main lever  30  at the engaging position via the tapered face  42  against the urging force of the third return spring  70 , and, in the same manner as the energization period of the coil  14  of the attraction type solenoid  10 , the operation of the main lever  30  from the engaging position to the disengaging position is allowed. As shown in  FIG. 3 (D), thereafter, while the sublever  40  is pressed down and held, the main lever  30  in which the operation from the engaging position to the disengaging position is allowed is pressed down via the tapered face  38  to the disengaging position against the urging force of the first return spring  60 , and the shift lock pin  108  can be passed through the beginning portion of the guide groove  110  to be moved to the lower end portion of the shift lock groove  109 . According to the configuration, even when an operation of depressing the foot brake is not involved and the coil  14  of the attraction type solenoid  10  of the locking device is not energized, the shift lever  103  can be shift-operated from a range position other than the P-range to the P-range position. The locking device is provided with the mechanical shift lever unlocking function.  
         [0056]     After the shift lever  103  is shift-operated from a range position other than the P-range to the P-range position, the shift lock pin  108  is returned and held to an upper end portion of the shift lock groove  109 , and the locking device is returned to the locked state shown in  FIG. 3 (A).  
         [0057]     In the locking device of the embodiment, if the shift lock pin  108  is to be passed with being advanced from the right side of the main lever  30  to the left side, and further passed with being returned from the left side to the right side, the right upper edge portion of the first engagement portion  31  of the main lever  30  may be chamfered to add a tapered face  39  to an upper end portion of the right side face of the first engagement portion  31  as shown in  FIG. 5 . According to the configuration, in the nonenergization period of the coil  14  of the attraction type solenoid  10 , the passage of the shift lock pin  108  from the right side of the main lever  30  to the left side is restricted, and, as a result of energization, the main lever  30  is pressed down via the tapered face  39  to the disengaging position against the urging forces of the first and third return springs  60 ,  70 , thereby allowing the passage of the shift lock pin  108 . The passage of the shift lock pin  108  from the left side of the main lever  30  to the right side is enabled by the above-mentioned mechanical shift lever unlocking function. The locking device of the modification shown in  FIG. 5  is configured in the same manner as the locking device of  FIG. 1  except the tapered face  39 . Therefore, the identical components are denoted by the reference numerals, and their description is omitted.  
         [0058]     As described above, as shown in, for example,  FIG. 5 , the locking device of the embodiment is enabled to conduct the shift lever lock at a predetermined range position other than the P-range position by changing the tip end shapes of the main lever  30  and the sublever  40 . Furthermore, the locking device can be preferably used in a shift lever mechanism for a vehicle automatic transmission apparatus other than the shift lever mechanism shown in the embodiment. The locking device is not restricted to a shift lever lock of a vehicle automatic transmission apparatus, and may be used in locking in various products such as a door lock of a household electrical appliance. Namely, the locking device has an excellent versatility.