GB2438422A

GB2438422A - Obstacle detecting apparatus for a powered door system

Info

Publication number: GB2438422A
Application number: GB0610135A
Authority: GB
Inventors: Terence Christopher Platt
Original assignee: Memco Ltd
Current assignee: Memco Ltd
Priority date: 2006-05-22
Filing date: 2006-05-22
Publication date: 2007-11-28
Anticipated expiration: 2026-05-22
Also published as: WO2007135371A1; GB0610135D0; GB2438422B

Abstract

An obstacle-detecting apparatus for a powered door or a frame of the door includes a circuit board 76, a surface-mount element for emitting or receiving radiation 78 and a radiation re-directing device 80. The surface-mount element and radiation re-directing device are both mounted on the circuit board, the radiation re-directing device being at a defined position relative to the surface-mount element. The re-directing device includes a reflecting member, mounted to sit at a defined angle relative to radiation emitted from or received by the surface-mount element, for re-directing the radiation. That system works in association with a visible-light display system to inform persons approaching an elevator car whether it is possible to safely enter the car.

Description

OBSTACLE-DETECTING APPARATUS FOR A POWERED DOOR SYSTEM

The subject invention relates to an apparatus for detecting an obstacle proximate a powered door, and more particularly, to a detection apparatus which includes a device for re-directing emitted or received radiation.

The subject invention finds particular application in detecting obstacles forward of powered door systems, for instance, in detecting a person standing forward of an elevator landing door or doors. Elevator systems are built with either a single sliding door on each landing, which door closes on a slam post, or with a pair of doors that meet at a central position. For safety and maintenance reasons, as well as for efficient operation, the elevator system needs to monitor proximity of people or objects to the doors, parti-cularly anything forward of the doors. Such "obstruction detection" may be used to override or modify a normal timed closing response of the elevator door or doors, and may either prevent a door from starting to close or reverse a closing movement already underway.

Among schemes used for obstruction detection are beam-interruption schemes that employ an infrared emitter diode for directing infrared light crossing the plane of a door to a receiver diode, and which detect the presence of an ob-struction by a break in the light beam. The receiver diodes are connected to detection circuitry which responds to beam interruption to generate a drive signal for stopping or reversing door closure. Another scheme utilizes "a curtain of light" in which a plurality of infrared emitter diodes are positioned along the edge of a door or on a door frame and an equal number (or a lesser number) of infrared receiver diodes are positioned along an edge of a second door or on the opposite door frame. Figure 1 illustrates one such curtain scheme, with emitter diodes being shown on the right and receiver diodes on the left. The number of receiver diodes can be different from the number of emitter diodes (as in Figure 1), or they can be equal in number. Earlier schemes used "proximity detection", which depended upon detection of capacitive change due to the presence of an obstacle, e.g. people or objects. However, calibration and maintenance difficulties have largely led to discontinuance of proximity detectors.

In a first aspect, the subject invention relates to an obstacle-detecting apparatus for a powered door or a frame of such a door. The apparatus includes: a circuit board; a surface-mount element for emitting or receiving radiation, the element being mounted on the circuit board; and, a radi-ation re-directing device mounted on the circuit board at a defined position relative to the surface-mount element, the device comprising a reflecting member mounted to sit at a defined angle relative to radiation emitted from or received by the surface-mount element, the reflecting member re-directing the radiation.

Preferably, the apparatus further includes one or more additional surface-mount elements and an equal number of radiation re-directing devices, radiation from or radiation to each surface-mount element being re-directed by a res-pective one of the radiation re-directing devices.

Preferably, the apparatus further includes a housing containing the circuit board, the surface-mount element or elements and the radiation re-directing device or devices, the housing including: a channel member attachable to an edge of the powered door or frame of such door; and, a radiation- transparent cover member for connecting to the channel mem-ber, radiation from the surface-mount element or elements exiting or entering the housing through the cover member.

More preferably, the cover member is formed of plastic and the channel member is formed of extruded aluminium.

Preferably, the defined angle is = 30 , and more pre-ferably, is approximately 210.

Preferably, the reflecting member is formed of alumi-nized plastics film.

Preferably, the radiation is infrared light.

Preferably, each surface-mount element for emitting radiation is a surface-mount focussed infrared emitting diode, or is a surface-mount infrared receiving diode.

The radiation re-directing device may be a prism.

Preferably, the radiation re-directing device also includes a frame member on which the reflecting member is mounted. More preferably, the frame member has an integral construction that includes: two rectangular side members; and, a sloping member extending between the side walls for supporting the reflecting member, the sloping member extend-ing at an angle to the side members and having a raised first end at one end of the side members and a non-raised second end at a bottom intermediate position on the side members.

Still more preferably, the defined position of the radiation re-directing device relative to the surface-mount element is such that: an end of the reflecting member, adjacent the second end of the sloping member, abuts the surface-mount element when that element is a radiation-emitting element; and, the other end of the side members abut the surface-mount element when that element is a radiation-receiving element.

Even yet more preferably, the circuit board has a series of pre-drilled holes, each for receiving a respective leg of the radiation re-directing device, the position of the pre-drilled holes positioning the radiation re-directing device relative to the surface-mount element.

In a second aspect, the subject invention relates to an obstacle-detecting system for either a pair of powered doors or a powered door and a frame of such door. The system includes: a first obstacle-detecting apparatus, comprising the apparatus of any preceding claim when the surface-mount element is an element for emitting radiation; a second obstacle-detecting apparatus, comprising the apparatus of any preceding claim when the surface-mount element is an element for receiving radiation; and, control means linked to both the first and second obstacle-detecting apparatuses, the control means being adapted to measure the amount of emitted radiation and the amount of received radiation, and to deter-mine from the two amounts when an obstacle is detected.

Preferably, the system further includes at least one visible-light display module capable of displaying a differ-ent colour at different times, the displayed colour depending on the position of the powered door or doors.

Preferably, the emitted radiation is re-directed by the first obstruction detection apparatus toward an obstruction zone forward of the powered door or doors.

Preferably, the emitted radiation is re-directed by the first obstruction detection apparatus toward an obstruction zone intermediate of a pair of powered doors or intermediate a powered door and a frame of such door.

Preferably, each powered door of the apparatus or system is an elevator door.

Preferred features of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which:-Figure 1 is an illustration of a detection scheme that utilizes a curtain of light across a door opening, the scheme involving a greater number of transmitters (right side) than receivers (left side); Figure 2 illustrates "approach detecting" of an obstacle positioned forward of a powered door; Figure 3 illustrates a serial arrangement for inters-persing, on an elevator door edge, visible-light modules with the obstacle-detecting apparatuses of the subject invention; Figure 4 illustrates a parallel arrangement for inter-spersing, on an elevator door edge, a series of visible-light modules so as to extend in parallel with a series of the obstacle-detecting apparatuses of the subject invention; Figure 5 a side view of a visible-light module used in the arrangements of Figures 3 and 4; Figure 6 is a plan view of the visible-light module of Figure 5; Figure 7 is a plan view illustrating a pair of car doors and a pair of landing elevator doors in an embodiment of the subject invention, one of the car doors having an obstacle-detecting apparatus for emitting radiation fitted to its outward edge and the other car door having an obstacle-detecting apparatus for receiving radiation fitted to its outward edge; Figure 8 is a cross-sectional view through one end of a housed obstacle-detecting apparatus; Figure 9 is a first perspective view of an obstacle-detecting apparatus for emitting radiation in an embodiment of the subject invention; Figure 10 is a second perspective view of the obstacle-detecting apparatus of Figure 9, the view being from the opposite direction to that in Figure 9; and, Figure 11 is a perspective view of a obstacle-detecting apparatus for receiving radiation in the embodiment of the subject invention.

In the described embodiment, the invention is applied to "approach detecting", in which an obstacle in front of a door or doors is detected, as illustrated in Figure 2. Surface-mount infrared radiation emitters and receivers are utilized, and the radiation passing from or to them is re-directed by respective reflectors without the need individually to adjust the position of the respective reflector relative to the emitter or receiver. In particular, the angle at which the reflector is placed relative to the incident light beam has been found to be an important factor. We have found that if a reflector is placed such that the reflector abuts or nearly abuts a surface-mount emitter diode, it is possible to re-direct focussed infrared light emitted by the diode if the reflector is maintained at a shallow angle of less than ap-proximately 30 with respect to the emitted light. In regard to received infrared light, we have found that a shallow angle on the reflector also gave the best result, but that the receiver diode needs to be placed further from the reflector than is the case with the emitter diode.

Figures 3 and 4 indicate two arrangements for placing infrared light emitters or receivers 30 on the edge of the inside panel of a landing door of an elevator. Either the infrared emitters or receivers may be serially interspersed with visible-light modules 32 as in Figure 3, or they may be arranged in parallel as in Figure 4. A more complete des-cription of these two arrangements is provided in WO 2004/ 001764. Each of the visible-light modules 32 may be similar to that shown in side view in Figure 5, and in perspective view in Figure 6. A red light-emitting diode (LED) 34 and a green LED 36 sit on either end of a transparent plastic block 38. Light is reflected within the plastic block 38 and exits the block through a light diffuser 40. The light diffusers are shown as the rectangular blocks in the visible-light modules 32 in Figure 3. The visible-light modules 32 turn green when the doors open and turn flashing red' as soon as the doors start to close.

We thus have developed an obstacle-detecting apparatus in which a radiation re-directing device sits next to a sur-face-mount emitter (or receiver) diode on a printed circuit board. The re-directing device includes a reflective element preset at a defined angle in a plastic frame; the plastic frame has legs that fit into respective pre-formed holes in the circuit board, allowing accurate positioning of the frame on the board relative to the position of the surface-mount emitter or receiver, and thereby accurate re-direction of the radiation. In the described embodiment, radiation from an emitter diode is re-directed from one direction to a second direction that extends toward a detection zone positioned forward of the door. Any obstacle in the detection zone will reflect part of the incident radiation, and part of the re-flected radiation is re-directed toward a second re-directing device on a second door or on the door frame, which second re-directing device in turn re-directs the reflected radi-ation toward an infrared receiver diode.

As depicted in the plan view of Figure 7, two-door elevator systems utilize a pair of car doors 50 that travel with an elevator car (not shown), and a pair of landing doors 52 on each floor landing. The control system operates such that, when the elevator car reaches a particular floor, the pair of car doors 50 begins to open in a synchronized manner with the opening of the pair of landing doors 52 on that floor. The back of each car door 50 faces a respective one of the landing doors 52, while an elevator user normally sees only the front of the car doors and landing doors. Each door 50 and 52 is normally constructed of a heavy-gauge metal with a double bend formed at both side edges such that an inside lip extends into the cavity that separates the doors 50 and 52. Thus, an inside lip 54 on each car door 50 faces a respective inside lip 56 on the respective landing door 52.

As can be seen from Figure 7, the facing inside edges 58 of the landing doors 52 always remain slightly closer to each other than do the facing inside edges 60 of the car doors 50.

In the preferred embodiment, visible-light modules 32 are interspersed vertically (Figure 3) on each inside lip 54 of a car door 50 with the obstacle-detecting apparatuses 64 (each in a housing). On the inside lip 54 of one car door 50 is a first apparatus 64 having one or more surface-mount elements that only emit radiation, while on the inside lip 56 of the other car door 50 is a second apparatus 64 having one or more surface-mount elements that only receive radiation.

Figure 4 illustrates a possible alternative arrangement, in which the visible-light modules are grouped together to form a first vertical channel 68, while obstacle-detecting appar-atuses are grouped together in an adjacent second vertical channel 70.

An end section of an obstacle-detecting apparatus in a housing is shown in cross-section in Figure 8. It includes a two-part housing formed by extruded-aluminium channel member 72 and an infrared_light_transparent plastic cover member 74 that is snap-fitted onto end of the channel member 72. To the inside of the channel member 72 is secured a circuit board 76 on which is mounted a surface-mount (SM) infrared emitter diode 78. The emitter diode 78 is "pre-focussed", meaning that its output beam is contained within a cone with a small conical angle. As depicted in Figure 8, that conical angle is about 20 .

Secured to the circuit board 76 in front of the emitter diode 78 so as to closely abut that diode is a radiation re-directing device 80. The relatively close positioning of the emitter diode 78 and the re-directing device 80 on circuit board 76 is shown in Figures 8, 9 and 10. The re-directing device 80 includes a moulded-plastic frame member 82 and a reflecting member formed by a piece of aluminized plastics film 84. The film piece 84 is shaped to sit on a sloped section 86 of the frame member 82, with its upper end secured under a first-end section 88 of the frame member 82 and its two lower sides secured under flanges 90. The film piece 84 extends at an angle of 21 to the surface of circuit board 76. The re-directing device 80 is secured to the circuit board 76 by four integral legs 92 that extend through pre-drilled holes in the board 76; the outer end of each leg 92 is deformed by heat to permanently fix the re-directing device 80 to the board 76.

Figure 11 illustrates that the same re-directing device can be used with an infrared receiving diode 94 on a circuit board 96. In this case, however, the re-directing device 80 is positioned such that a dome on one of its sides is aligned with a spacing gap between two side walls of frame member 82 at a second-end section 98 of that frame member.

The receiver diode is mounted further from the re-directing device 80 than the emitter diode so as to narrow down the field-of-view of the receiver diode and prevent direct infra-red light from the emitter diode being received, thereby shielding it.

In operation of an elevator car between floors, the visible-light modules 32 display no colour. As the elevator car reaches a landing floor and the car doors 50 are opened, the modules turn green. When fully open, the car doors are approximately one metre apart. The system is able to sense an obstacle that is up to approximately one metre in front of the plane of the elevator car doors 50. As the car doors 50 begin to close, the visible-light modules turn red and begin to flash. The obstacle-detecting apparatuses 64 on the res-pective car doors 50 move toward each other and in doing so sense an obstacle proportionately closer to the plane of the car doors 50. For instance, when the gap between the car doors 50 is only 20cm, only obstacles that are = 20cm from the plane of the car doors are detected. Colour change in the visible-light system is controlled by a computer based on the position of the doors. The computer also senses the position of the car doors and measures the amount of emitted radiation and the amount of received radiation. If the computer deter-mines that an obstacle is in the obstruction zone forward of the doors, the car doors will not close or, if closing, will reverse their movement, and the colour display will again turn green. On starting to close again, the car doors 50 go flashing red again, and when closed, the colour display on the visible-light modules turns off.

Although the description of the preferred embodiment related to a two-door elevator system, the subject invention is equally applicable to a one-door system. In that case, either a emitting or receiving obstacle-detecting apparatus would be positioned on the outer edge of the door, with a respective receiving or emitting obstacle-detecting apparatus being positioned on the "slam post". A slam post in a single-door elevator system is that part of the elevator door frame onto which an outer edge of the door abuts when closed.

Although obstacle detection has been described in which the obstacle is located forward of the plane of opened doors, it is also possible to utilize the system of the invention to detect an obstacle in the plane of the opened doors. In such case, a first radiation re-directing device re-directs radiation from a surface-mount radiation-emitting device on one side of a door opening to extend along the plane of the elevator door or doors, and that radiation is then directed to a surface-mount radiation-receiving device on the other side of the door opening by a second radiation re-directing device.

The preferred embodiment has described the radiation re-directing device as comprising a reflecting member mounted on a frame member. However, it is possible for the re-directing device to be a prism of solid plastics or other material, in which case the prism serves the twin functions of providing a reflecting surface and supporting that surface at a defined angle and spacing from the emitter diode or receiver diode.

While the present invention has been described in its preferred embodiments, it is to be understood that the words which have been used are words of description rather than limitation, and that changes may be made to the invention without departing from its scope as defined by the appended claims.

Each feature disclosed in this specification (which term includes the claims) and/or shown in the drawings may be in-corporated in the invention independently of other disclosed and/or illustrated features.

The text of the abstract filed herewith is repeated here

as part of the specification

An obstacle-detecting apparatus for a powered door or a frame of the door includes a circuit board, a surface-mount element for emitting or receiving radiation, and a radiation re-directing device. The surface-mount element and radiation re-directing device are both mounted on the circuit board, the radiation re-directing device being at a defined position relative to the surface-mount element. The re-directing device includes a reflecting member, mounted to sit at a defined angle relative to radiation emitted from or received by the surface-mount element, for re-directing the radiation.

The re-directing device also includes a moulded-plastic frame member on which the reflecting member sits and which is used to position the reflecting member relative to the surface-mount element. The reflecting member abuts a surface-mount emitter diode that emits radiation. The same re-directing device may be used with a receiving diode, but then the reflecting member is positioned on the circuit board to sit further from the diode; in that case, an end wall of the frame member is used for setting an appropriate distance between the re-directing device and the receiving diode. The re-directing device might alternatively be a prism. An obstacle-detecting apparatus with an emitter diode or diodes forms, together with an obstacle-detecting apparatus with a receiving diode or diodes, a system for detecting an obstacle in front of or between the powered doors. That system works in association with a visible-light display system to inform persons approaching an elevator car whether it is possible to safely enter the car.

Claims

CLAIMS: 1. An obstacle-detecting apparatus for a powered door or a

frame of such a door, the apparatus comprising: a circuit board; a surface-mount element for emitting or receiving radiation, the element being mounted on the circuit board; and, a radiation re-directing device mounted on the circuit board at a defined position relative to the surface-mount element, the device comprising a reflecting member mounted to sit at a defined angle relative to radiation emitted from or received by the surface-mount element, the reflecting member re-directing the radiation.

2. The apparatus of claim 1, further comprising one or more additional surface-mount elements and an equal number of radiation re-directing devices, radiation from or radiation to each surface-mount element being re-directed by a respect-ive one of the radiation re-directing devices.

3. The apparatus of claim 1 or 2, further comprising a housing containing the circuit board, the surface-mount element or elements and the radiation re-directing device or devices, the housing comprising: a channel member attachable to an edge of the powered door or frame of such door; and, a radiation-transparent cover member for connecting to the channel member, radiation from the surface-mount element or elements exiting or entering the housing through the cover member.

4. The apparatus of claim 3, wherein the cover member is formed of plastic and the channel member is formed of extruded aluminium.

5. The apparatus of any preceding claim, wherein the defined angle is = 30 .

6. The apparatus of claim 5, wherein the defined angle is approximately 21 .

7. The apparatus of any preceding claim, wherein the reflecting member is formed of aluminized plastics film.

8. The apparatus of any preceding claim, wherein the radiation is infrared light.

9. The apparatus of any preceding claim, wherein each surface-mount element for emitting radiation is a surface-mount focussed infrared emitting diode.

10. The apparatus of any of claims 1 to 8, wherein each surface-mount element for receiving radiation is a surface-mount infrared receiving diode.

11. The apparatus of any preceding claim, wherein the radiation re-directing device comprises a prism.

12. The apparatus of any one of claims 1 to 10, wherein the radiation re-directing device also comprises a frame member on which the reflecting member is mounted.

13. The apparatus of claim 12, wherein the frame member has an integral construction that includes: two rectangular side members; and, a sloping member extending between the side walls for supporting the reflecting member, the sloping member extend-ing at an angle to the side members and having a raised first end at one end of the side members and a non-raised second end at a bottom intermediate position on the side members.

14. The apparatus of claim 13, wherein the defined position of the radiation re-directing device relative to the surface-mount element is such that: an end of the reflecting member, adjacent the second end of the sloping member, abuts the surface-mount element when that element is a radiation-emitting element; and, the other end of the side members abut the surface-mount element when that element is a radiation-receiving element.

15. The apparatus of claim 14, wherein the circuit board has a series of pre-drilled holes, each for receiving a respective leg of the radiation re-directing device, the position of the pre-drilled holes positioning the radiation re-directing device relative to the surface-mount element.

16. An obstacle-detecting system for either a pair of powered doors or a powered door and a frame of such door, the system comprising: a first obstacle-detecting apparatus, comprising the apparatus of any preceding claim when the surface-mount element is an element for emitting radiation; a second obstacle-detecting apparatus, comprising the apparatus of any preceding claim when the surface-mount element is an element for receiving radiation; and, control means linked to both the first and second obstacle-detecting apparatuses, the control means being adapted to measure the amount of emitted radiation and the amount of received radiation, and to determine from the two amounts when an obstacle is detected.

17. The system of claim 16, further comprising at least one visible-light display module capable of displaying a different colour at different times, the displayed colour depending on the position of the powered door or doors.

18. The system of claim 16 or 17, wherein the emitted radiation is re-directed by the first obstruction detection apparatus toward an obstruction zone forward of the powered door or doors.

19. The system of claim 16 or 17, wherein the emitted radiation is re-directed by the first obstruction detection apparatus toward an obstruction zone intermediate of a pair of powered doors or intermediate a powered door and a frame of such door.

20. The apparatus of any one of claims 1 to 15, wherein the powered door is an elevator door.

21. The system of any one of claims 16 to 19, wherein each powered door is an elevator door.

22. An obstacle-detecting apparatus for a powered door or a frame of such door, the apparatus being substantially as herein described with reference to and as shown in the accom-panying drawings.

23. An obstacle-detecting system for either a pair of powered doors or a powered door and a frame of such door, the system being substantially as herein described with reference to and as shown in the accompanying drawings.