Abstract:
The present invention relates to external entrapment protection system that allows use of the same set of photoelectric transmitter/receiver units for both sensor types of a contact type sensor and a non-contact type sensor. A kit includes the entrapment system and an elastic profile and/or a photoelectric wall mounting unit.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit of U.S. Provisional Patent Application No. 61/238,815, filed Sep. 1, 2009, the entirety of which is hereby incorporated by reference into this application. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present relates to a contact and non-contact entrapment protection system and in particular to an optical sensor which can be used in either the contact or non-contact protection system. 
         [0004]    2. Description of the Related Art 
         [0005]    Contact type sensor entrapment systems are known. U.S. Pat. No. 6,897,630 describes a system for sensing forces on a movable barrier including a motor and a movable barrier. A potentiometer coupled to the door determines its position. A force detection mechanism is coupled to determine a first component force value applied by the motor. An entrapment system can use the first component force value generated by the motor which is scaled using a second component force value derived from an angular position of the a trolley arm connected to the movable barrier. 
         [0006]    U.S. Pat. No. 7,616,895 describes an optical safety edge with status and failure recognition. The optoelectronic safety sensitive edge for the safeguarded, motor-driven movement of a gate having a closing edge, operates with light from a light-transmitting device which is emitted dynamically and passed through a medium, such as air, to a light receiver device. In response to the light received, a dynamic, electrical coupling signal is generated, which is passed over an electric coupling lead back to the light-emitting device. The electric coupling signal is scanned and a release signal is generated in response to, that is, dependent on the electrical coupling signal detected. Bit-coded information concerning at least one operating parameter, such as the adjusting parameter of the light-transmitting device, is passed over the electric coupling lead. The light-transmitting device is comprised of the light transmitter and a transmitter control system. 
         [0007]    Non-contact type sensor entrapment systems are known. U.S. Pat. No. 7,228,883 describes a photo-electric eye safety system used in conjunction with a motorized barrier operator system having a primary photo-electric eye safety device, which includes a primary emitter mounted at one side of an opening enclosed by the barrier, and a primary receiver mounted on another side of the opening and aligned to receive a beam from said primary emitter, wherein a controller monitors the primary emitter and the primary receiver, and initiates corrective action if the beam is interrupted. A supplemental photo-electric eye safety system is used comprising a supplemental emitter including supplemental emitter terminals connectable to the controller and the primary receiver, and a supplemental receiver including supplemental receiver terminals connectable to the controller and the primary receiver. The system can be used for detecting obstructions of different heights in the path of a motorized movable barrier by emitting a first beam across the movable barrier&#39;s path, receiving the first beam, triggering emission of a second beam across the movable barrier&#39;s path at a height different than the first beam, receiving the second beam and initiating at least stoppage of the movable barrier if one of the beams is interrupted. 
         [0008]    According to the UL Standard for Safety for Door, Drapery, Gate, Louver, and Window Operators and Systems, UL 325, paragraph 30.1.1, any automatically operated commercial/industrial door operator has to be connected to an external entrapment protection device. In paragraph 30.2.1, the standard states that an external entrapment protection device provided with, or as an accessory to, a commercial/industrial operator (or system) shall consist either of a contact type sensor or a non-contact type sensor. Once this standard goes into effect on Aug. 29, 2010, operator and door manufacturers, as well as door installers, will have to ensure that every automatically operated commercial/industrial door is equipped with one of those types of sensors. As both of those types of sensors have advantages in different types of door installations, the decisions for the type of sensor creates a logistical challenge. The information of the type of door installation lies with the door installer, whereas the decision of which types of sensor will get shipped with the operator system, lies with the operator manufacturer. 
         [0009]    It is desirable to provide an external entrapment protection system that allows the use of the same set of photoelectric transmitter/receiver units for both a contact type sensor and a non-contact type sensor. 
       SUMMARY OF THE INVENTION 
       [0010]    The present invention relates to external entrapment protection system that allows use of the same set of photoelectric transmitter/receiver units for both sensor types of a contact type sensor and a non-contact type sensor. This allows the operator/manufacturer to ship the same transmitter/receiver units with every automatic operator and the installer can then decide to either install them as a contact or as a non-contact sensor. This provides a great logistical advantage for the operator manufacturers as they only have to deal with one expensive transmitter/receiver unit and do not have to have information about they type of door installation when they ship an automatic operator unit. The door installer can independently source and warehouse the inexpensive elastic profiles and photoelectric wall fixture units. 
         [0011]    The invention will be more fully described by reference to the following drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]      FIG. 1  is a schematic diagram of an entrapment protection system in a contact sensor type embodiment. 
           [0013]      FIG. 2  is a schematic diagram of the entrapment protection system in a non-contact sensor type embodiment. 
           [0014]      FIG. 3  shows a safety sensitive edge with reference to a safeguarding closing edge in an exploded representation; 
           [0015]      FIG. 4  shows a diagrammatic sketch of an inventive safety sensitive edge in a first operating state; 
           [0016]      FIG. 5  shows the inventive safety sensitive edge of  FIG. 4  in a second operating state. 
       
    
    
     DETAILED DESCRIPTION 
       [0017]    Reference will now be made in greater detail to a preferred embodiment of the invention, an example of which is illustrated in the accompanying drawings. Wherever possible, the same reference numerals will be used throughout the drawings and the description to refer to the same or like parts. 
         [0018]    Entrapment protection system  10  provides a non-contact type sensor to create a non-contact sensor application and a contact type sensor to create a contact sensor application. For example, the contact type sensor and the non-contact type sensor can include through-beam photoelectric sensors including a transmitter transmitting light and a receiver receiving it both in separate units or reflective photoelectric sensors including a combined transmitter/receiver unit in which the transmitter transmits light onto a unit with a reflective surface and the receiver receives the reflected light. In one embodiment, a reflective system can be used as a contact or non-contact sensor is described in U.S. Pat. No. 5,790,259, hereby incorporated by reference. Non-contact sensors and contact sensors can include a communication interface for communicating signaling information. The communication interface can include, for example, a dynamic output signal, transistor output signal or relay output signal. 
         [0019]    In the contact type sensor application, transmitter/receiver units  12  are inserted into elastic circular profile  14 . Elastic circular profile  14  can be connected to bottom edge  15  of moving part of the door  16 , as shown in  FIG. 1 . For example, bottom edge  15  can be formed of polymeric or elastomeric material. The contact sensor formed by transmitter/receiver units  12  gets activated by “contacting” the elastic material of elastic circular profile  14  which then interrupts the flow of light inside the circular profile. 
         [0020]    In one embodiment, transmitter/receiver units  12  can be optical devices. U.S. patent application Ser. No. 11/371,836, hereby incorporated by reference into this application, provides a description of contact sensor operation principles and as shown in  FIGS. 3 and 4 . Safety sensitive edge  100 , which is to be fastened to a roller shutter, of which a shutter segment  140  is shown in  FIG. 3 . Sensitive edge  100  comprises, as essential components, an optical transmitter device  121  and an optical receiver device  122 , which are coupled over an electric coupling lead  123  and the light path between the transmitter device and the receiver device, so that a feed-back loop is created. In a manner not shown, lead  124  connects electrical coupling lead  123  with evaluating device  130 . In the example shown, safety sensitive edge  100  detects the deformation of a hollow rubber profile  110 , which is constructed rectangularly and has a so-called switch chamber  111  as well as a tracking chamber  112 , both of which extend at a distance from one another along a hollow profile. In the embodiment shown, the switching chamber  111  is constructed in the shape of a hollow cylinder, the optical transmitter device  121  being introduced at a first end and the assigned optical receiver device at the other end of the profile. The periphery of the transmitter device as well as that of the receiver device is fitted to the periphery of the switching chamber, so that these can simply be inserted. The transmitter device  121  comprises a light transmitter  121   a  in the form of an LED and an assigned transmitter control  121   b , which triggers the light transmitter to emit light. In an appropriate manner, the receiver device  122  comprises an optical receiver  122   a  in the form of a photodiode, which is matched to the light emitted by the light transmitter  121   a . Accordingly, the components given form an optoelectronic sensitive edge, at which the light, emitted by the light transmitter  121   a , is taken up by the receiver  122   a , converted into electrical pulses assigned to the optical pulses and transmitted over the electric coupling lead  123  back to the light transmitter. The components named accordingly form a feedback system. 
         [0021]    On the longitudinal side, which faces the closing edge  141  of the gate, the hollow rubber profile  110  has two link plates  114 , which enable lateral insertion in a C profile  142 . The C profile  142  itself is fastened to the closing edge  141  of the gate by means of screws. 
         [0022]    As already stated, the dynamic electric coupling signal from the electric coupling lead  123  is tapped by the lead  124  and taken to the evaluating device  130 , which works as a central control device. The electric coupling signal is evaluated there and, in response thereto, that is, depending on the coupling signal detected, an output signal S 1  of the optoelectronic safety sensitive edge  100 , which is put out over the output signal lead  131  and is referred to as the release signal, is generated. This output signal of the sensitive edge is taken in a manner not shown to a control system for the gate driving mechanism, which evaluates the signal, for example, in order to move the gate further in the closing direction as requested by the release signal, or to stop or reverse the gate, when the actuation of the safety sensitive edge is detected. This operating state occurs, if, during the movement of the closing edge  141 , the latter is moved against an obstacle, as a result of which, to begin with, the hollow profile  110  comes up against the obstacle and is deformed. 
         [0023]    Reference is made to  FIG. 4 , which represents a diagrammatic sketch of the sensitive edge, for describing the mode of functioning of the inventive safety sensitive edge. The safety sensitive edge comprises the sensor system, consisting of the hollow profile  110  and the coupled transmitter and receiver devices  121 ,  122 . The evaluating device  130  is connected with the sensor system over the electrical tapping lead  135 , which is connected to the electrical coupling lead  123 . For supplying the sensor system with energy, the evaluating device  130  has a controllable voltage source  133 , with which the transmitter device  121  and the receiver device  122  are connected over the supply leads  137 . In this respect, the lead connection  124  in  FIG. 3  of corresponds to the tapping lead,  135 , and the supply leads  137 , shown in  FIG. 4 . 
         [0024]    Optical transmitter  121   a  emits dynamic light pulses, which are shown as an optical coupling signal K 1 . These light pulses are detected by the receiver device  122  and converted in a predetermined manner into an electrical coupling signal K 2 , which is fed back over the electric lead  123  to the transmitter device  121 . Information as to whether the light, emitted by the transmitter device  121 , has arrived at the receiver device  122 , is supplied over this feedback to the optical transmitter device  121 . The electrical coupling signal, detected by means of the tapping lead  135 , is supplied to a processor  132  in the evaluating device  130 , which represents the intelligence of the evaluating device. The processor has an A/D converter, which is not shown in the Figure, in order to convert the electrical coupling signal detected, so that the information can subsequently be processed digitally. 
         [0025]    The electrical coupling signal K 2  is processed in the processor in order to determine whether or not the safety sensitive edge is actuated, that is, whether the light path between the transmitter  121   a  and the receiver  122   a  is or is not obstructed. Depending on the result of the data processing, the evaluating device  130  emits a corresponding release signal S 1 , the variation of which over time is shown to the left of the signal lead, over the signal lead  131 . In the operating situation shown in  FIG. 4 , the light pulses are received by the receiver device  122  and converted into electrical pulses, which are placed on the electrical coupling lead  123 . These electrical signals, arriving at the transmitter device, are then used, in turn, for controlling the output of corresponding optical light pulses, which are detected by the receiver device  122  and processed further, as described, etc. If no obstacle is detected, the signal S 1  indicates that the driving mechanism can be actuated further. 
         [0026]    In order to achieve at least batchwise a certain adaptation of the safety sensitive edge to changed operating conditions, as caused by surrounding light or ageing phenomena of the participating components, provisions are made so that the power, with which the light transmitter  121   a  sends out light pulses, is adjusted automatically. This is accomplished in that the transmitter  121   a  sequentially emits light pulses with different intensities, and the light intensity, which is required so that the receiver  122   a  still recognizes these light pulses, is determined in this way. Such an automatic adaptation of the system to the circumstances is very advantageous. However, for conventional safety sensitive edges, information concerning how individual operating parameters of the system must be adjusted so that the operation can be maintained, is not available in the evaluating device. 
         [0027]      FIG. 5  shows another operating situation, which is different from that of  FIG. 4 . The optical path between the transmitter device  121  and the receiver device  122  is interrupted by an elastic deformation  115  of the closing profile  110  caused by an obstacle, which is not shown, so that the receiver  122   a  transmits an appropriate electrical coupling signal K 2  to the transmitter  121  over the electrical coupling, lead  123 . A comparison of the signal K 2 ′ with the operating situation in  FIG. 2  shows that the electrical coupling signals K 2  and K 2 ′ are different. This is also detected over the tapping lead  135  by the processor  132 , which subsequently, in response to the electrical coupling signal detected, puts out an assigned release signal S 1  to the output signal lead  131 . This signal S 1  differs from the output signal of the situation shown in  FIG. 4  and causes the driving mechanism, which is not shown, to be stopped or reversed. 
         [0028]    The system of the present invention fulfills the above-described monitoring requirement, as well as the edge sensor requirements described in paragraph 36 of the UL 325 standard. 
         [0029]    To create a non-contact sensor application, transmitter/receiver units  12  are installed into the photoelectric wall mounting units  18 , as shown in  FIG. 2 . Transmitter unit  20  emits a light beam  21  that is received by receiver unit  22 . Sensor  23  is activated by interrupting light beam  21 . The combination of the optical characteristics of transmitter/receiver units  12  and photoelectric wall mounting units  18  ensure that system  10  meets the sensitivity requirements of paragraph 35.3 and the ambient light test of paragraph 35.4 of the UL 325 standard. 
         [0030]    Alternatively, transmitter/receiver units  12  are combined transmitter/receiver units in which the transmitter transmits light onto a unit with a reflective surface and the receiver receives the reflected light. 
         [0031]    In one embodiment, a kit can include transmitter/receiver units  12 , elastic circular profile  14 , and/or photoelectric wall mounting units  18 . 
         [0032]    It is to be understood that the above-described embodiments are illustrative of only a few of the many possible specific embodiments, which can represent applications of the principles of the invention. Numerous and varied other arrangements can be readily devised in accordance with these principles by those skilled in the art without departing from the spirit and scope of the invention.