JP2002193573A - Method and system for detecting object in detection zone - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an improved three-dimensional door safety detecting system for a sliding door. SOLUTION: The system and method of detecting an object existing in a three-dimensional field adjacent to a door passage such as an elevator door passage has an energy transmitter row 40 for transmitting the three-dimensional signal to the field and an energy detector row 42 for receiving the energy signal reflected from the object. The signal is sampled by the predetermined times. For an example, when the minimum value of the sampling signal reaches a threshold value, the object detecting signal is generated. For other example, when a fluctuation range of the sampling signal exists within the predetermined fluctuation range, the object detecting signal is generated. In another example, when the predetermined modulation code is detected from the sampling signal, the object detecting signal is generated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to an elevator,
In particular, it relates to an electronic safety detection system for elevator doors.

[0002]

BACKGROUND OF THE INVENTION Elevator equipment is equipped with a plurality of automatic sliding doors with a safety system designed to detect objects that may interfere with the closing operation of the automatic sliding door. Such safety systems typically include multiple signal sources (emitters) located on one door,
Multiple signal receivers (receivers) located on the other door
And From the signal source, a curtain-type signal is transmitted across the threshold of the elevator door, and this signal is received by the signal receiver. If this curtain-type signal is interrupted, the safety system may communicate with the door control to stop the door closing operation and open the door or to move the door to the open position, depending on the current position of the door. maintain.

A doorway safety system that uses a sonic transmitter and receiver to detect an object or a person present in an area near an elevator door is disclosed in US Pat.
29,176 (Mills). In this system, an object straddling a threshold between doors is detected, and a detection zone is extended to an entrance passage. A signal is generated at an angle from the transmitter and reaches the entrance passage. When an obstruction enters the detection zone, the signal is reflected by the obstruction and detected by the receiver.

Another doorway safety system is described in US Pat. No. 5,886,307 (Full et al.), Which detects objects straddling a threshold or present in an entryway. A three-dimensional system is disclosed. In this system, a curtain-type light beam is projected over a threshold, and a region immediately before an entrance passage is irradiated with a three-dimensional detection beam. The system detects such an obstacle when one or more beams are blocked by an obstacle straddling a threshold between the doors. In addition, if the energy of the three-dimensional beam is reflected by an object in the entrance passage and enters the three-dimensional receiver, this object is also detected.

[0005] The three-dimensional sensing system described above has significant disadvantages. For example, in a curtain-type detection system,
Whereas one or more curtain beams need to be "blocked" to indicate an obstacle straddling the threshold, three-dimensional sensing is "connected" to indicate an obstacle. Need to be Thus, the logic is reversed in three-dimensional sensing, resulting in sensitivity to external energy sources that is not a problem in single-plane or curtain-type sensing systems.

Systems using light as the energy source for three-dimensional sensing are susceptible to interference from various external sources. A light source external to the sensing system, for example in the vicinity of an elevator installation, can be erroneously picked up by a light sensor in the sensing system. If the light from the external light source is modulated as well as the light emitted from the door security system, the light will be picked up and interpreted as indicating an obstacle. Such external light sources include fluorescent lighting systems, emergency strobe lights, and emergency vehicle beacons.

[0007] External sources of impulse-type electrical noise can also cause the detection of disappointing obstacles in three-dimensional door safety systems. Sources of this type of electrical noise include relay-type elevator controls and electro-mechanical door actuators.

[0008]

It is an object of the present invention to provide an improved three-dimensional door safety detection system for a sliding door.

Another object of the present invention is to provide a three-dimensional door safety detection system that operates reliably in the presence of impulse-type electrical noise.

It is yet another object of the present invention to provide a three-dimensional door safety detection system that operates reliably in the presence of an external light source including a light source that generates light energy having characteristics similar to the light energy generated by the detection system. It is to provide.

[0011]

SUMMARY OF THE INVENTION The above and other objects of the invention are achieved in a manner as described herein.

The present invention relates to a three-dimensional door safety system for detecting objects or persons approaching or within a predetermined safety zone of an open door. Multiple receivers or detectors are located on one door, and multiple emitters are located on the opposite door. The area just before the closing door is scanned to detect obstacles. An object in the entrance passage is detected by the safety system. At this time, the external energy not generated by the safety system is identified. Generally, each beam generated from the energy emitter is sampled.
The intensity of each beam is stored. This intensity is compared with a predetermined detection threshold level to determine whether an object is present in the detection area.

The first embodiment of the invention takes into account the transient nature of the interference energy, that is to say that it is not detected after a very short time. In this embodiment, each three-dimensional beam is sampled multiple times per door scan frame. By comparing the value of the sample with the smallest intensity among the obtained samples with a predetermined detection threshold level, it is determined whether an object exists in the three-dimensional detection area. In this embodiment, most of the impulse-type interference (eg, electrical noise spikes or light generated from strobe lamps) is effectively ignored.

The second embodiment of the present invention also takes into account the transient nature of the interference energy. However, in this case, it is possible to continuously detect the interference energy other than the high intensity portion of the interference signal. In this embodiment, each three-dimensional beam is sampled multiple times per door scan frame. Each sample is stored for each beam. In one scan frame for a particular beam, the intensity of the detected energy reflected from the object in the three-dimensional detection area should be substantially constant from sample to sample, ie, within a predetermined variation range. If a sample of a particular beam does not exhibit such constant properties, the energy of this beam is considered interference energy and is ignored. This embodiment provides the first implementation by providing the ability to ignore continuously detectable but non-constant intensity interference energy, such as light emanating from certain fluorescent lighting systems. The case identification ability has been improved.

In a third embodiment of the present invention, the transmitted energy is marked to provide the ability to continuously detect and ignore interference energy of constant intensity. I have. In this embodiment, each three-dimensional beam is sampled only once per door scan frame, but with an individually identifiable modulation of the transmitted energy, ie, the transmitted energy modulates the modulation code. And this is confirmed by the sensing receiver. If this modulation code is detected in the sampled beam, a signal is generated to indicate that an object is present.
If the modulation code at the energy detected for a particular beam is not confirmed by the receiver, the energy detected for this beam, regardless of its intensity, is ignored as interference energy. In this embodiment, interference energies, such as light emitted by certain fluorescent lighting systems, that are continuously detectable and cannot be ignored in the first and second embodiments due to the relatively constant intensity. Ability to ignore.

Alternative embodiments of the present invention may use the solutions described above with respect to the three preferred embodiments in various combinations. By combining various solutions, the ability to discriminate between targeted detection energy and interference energy from external sources is improved.

The addition of three-dimensional sensing capability to door safety systems renders certain prior art systems inoperable under various circumstances due to the sensitivity to light from external sources and impulse noise. Such situations include elevator facilities utilizing relay-type controls and fire alarm systems using strobe light, facilities near emergency beacons (ie hospitals), and facilities near fluorescent lighting systems. , And the like. The present invention provides a system that operates reliably in such an environment and therefore operates more safely and economically.

[0018]

FIG. 1 shows a preferred embodiment of a door safety system (10) according to the present invention. The system comprises a hallway (14) and walls (18, 20).
Doorway (12) of elevator car (16) adjacent to
To open and close. One set of hall passage doors (24, 26) and one set of elevator car doors (2
8, 30) are illustrated. Both sets of doors (24, 2
6, 28, 30) slide together over the threshold (34) to open and close, but the hall passage doors (24, 26).
Opens and closes slightly earlier or later than the elevator car doors (28, 30). Safety detection system (3
8) is installed on the elevator car doors (28, 30) adjacent to the hallway doors (24, 26). The safety sensing system (38) comprises a row of transmitters (40) and a row of detectors (42), which are located on opposite sides of the doorway (12) and face each other.

As shown in FIG. 2, each transmitter row (40) includes a housing (46) and a transparent cover (48) for protecting the transmitter circuit board (50) and the transmitter lens board (52). Have. The transmitter lens substrate (52) includes a plurality of three-dimensional transmitter lenses (56) and a plurality of curtain transmitter lenses (58). The transmitter circuit board (50) includes a plurality of transmitters or light emitting diodes (LEDs) (60) for transmitting infrared light, which are disposed adjacent to each lens (56, 58). . A transmitter barrier (64) supports the housing (46) and partially blocks light from the three-dimensional transmitter lens (56).

The detector array (42) is configured as a mirror image of the transmitter array (40). The detector row (42) includes a detector row housing (66), the housing (66) having a transparent detector row cover (68) for protecting the detector circuit board (70) and the detector lens board (72). )have. The detector lens substrate (72) includes a plurality of three-dimensional detector lenses (76) and a plurality of curtain detector lenses (78). The curtain-type detector lens (78) is disposed straight with respect to the curtain-type transmitter lens (58). The detector circuit board (70) includes a plurality of detectors or photodiodes (80) adjacent each lens (76, 78) for detecting reflected light. The detector barrier (84) is connected to the detector housing (6).
6) and a three-dimensional detector lens (76)
Partially block the light to

The safety system (38) includes a control device (7).
7), and the control device (77) supplies and controls power to the transmitter array (40) and the detector array (42), and outputs signals to the transmitter array (40) and the detector array (42). To an array (sequence)
And controls the communication with the door control device (79).

The control device (77) includes a data collection / data processing circuit, which includes a power supply, an analog-to-digital converter, and a microprocessor.
Microprocessor (eg Motorola 68HC1)
1 or other commercially available microprocessor) further comprises a programmable memory for defining an execution program for detecting elevator door interferers.

In operation, an object or human threshold (34)
, Or approaching the doorway (12), the safety system (38) prevents the elevator car doors (28, 30) from closing.
A signal is generated from the curtain transmitter lens (58) and sent across the threshold (34) to the curtain detector lens (78). If this curtain signal is interrupted with the doors (28, 30) open or closing, the safety system (38)
In communication with the door control device (79), each of the doors (2)
8, 30) are kept open or the closing operation is reversed.

As shown in FIGS. 3 and 4, from the three-dimensional transmitter lens (56), a three-dimensional signal is generated outward at a predetermined angle and sent to the inside of the hall passage (14). . A detector (80) and a three-dimensional detector lens (76) receive signals originating from the three-dimensional transmitter lens (56) and reflected by the object at a predetermined angle. The overlapping area of the field of view (86) of the three-dimensional transmitter lens (56) and the field of view (96) of the three-dimensional detector lens (76) becomes a detection zone (94). If the object or human is in the detection zone
When entering 4), the three-dimensional transmitter lens (5
The signal from 6) hits an obstacle and is reflected back into a three-dimensional detector lens (76). When the three-dimensional detector lens (76) receives a signal, the safety system (38) processes the received signal to determine whether the signal indicates the detection of an obstacle. If so, the safety system (38) communicates with the door control (79) to reverse the closing action or keep the doors (28, 30) open.

In operation, the safety system (38) continuously scans the door opening and reacts to detected obstacles, if any, at each scan frame. Each scan frame consists of two stages. That is, a data collection stage and a data processing stage.

In the following description, the term "beam" refers to the signal generated from a curtain transmitter lens (58) or a three-dimensional transmitter lens (56).

In the data collection stage, each of the curtain beam and the three-dimensional beam is sampled, and the obtained beam data is stored. Curtain beams are sampled only once per scan frame, while three-dimensional beams are subject to the requirements of certain embodiments of the present invention.
Sampling can be performed twice or more per frame. A single sampling of a particular beam can be up to 7 times for both curtain and 3D beams.
Complete within 50 μs time.

In the data processing stage, it is determined whether an obstacle has been detected by processing the beam data accumulated in the data collection stage. A signal is sent to the door control (79) to indicate the presence or absence of a door obstruction.

The individual beams are sampled in the following manner. First, the beam transmitter is activated. The emitted energy signal is modulated so that the sensing circuit can reject light from an external source (eg, sunlight or light from an incandescent light bulb). The type of modulation used will depend on the particular embodiment of the invention.
After the beam transmitter is activated, the beam receiver is ready to receive the transmitted signal. All detected signals are processed by various circuits (gain selection, filtering, and rectification). The resulting signal is sent to the integrator stage. The output of the integrator changes while having a negative slope from the reference voltage which is the initial value. Subsequently, the output signal of the integrator is sent to a voltage comparison stage, where it is compared to a fixed hardware threshold voltage. If the output of the integrator falls below the fixed hardware threshold voltage, the "integration complete" signal is generated by the comparator. The time from the start of integration to the "end of integration" signal is a direct indication of the strength of the received beam signal. A shorter integration time indicates a stronger detected beam signal. This time (or intensity) value is stored for the beam being sampled. If no integration end signal is generated during the maximum sampling time of 750 μs, it is determined that the beam being sampled is in the “no detection” state.

The data processing stage basically consists in comparing the beam intensity values stored in the data collection stage with a predetermined detection threshold. If the signal detected for the three-dimensional beam exceeds a threshold, a signal is sent to the door control (79) to indicate that an obstacle has been detected.

In the first embodiment of the present invention, the transmitted beam signal is modulated by a continuous stream of fixed frequency rectangular waves, and each three-dimensional beam is sampled multiple times per scan frame. For a particular beam, only the value of the sample with the lowest beam intensity value is actually stored. Normal data processing as described above is performed. This embodiment is the simplest and quickest of the three embodiments described herein, since the interference elimination obtained by this embodiment is basically performed entirely in the data acquisition stage of the scan frame. .

In the second embodiment of the present invention, similarly to the first embodiment, the transmitted beam signal is modulated by a continuous flow of a fixed-frequency rectangular wave, and each three-dimensional beam is scanned for each scanning frame. Sampled multiple times. However, unlike the first embodiment, the beam intensity value of each sample is stored for each beam. In the data processing stage, the beam intensity of each individual beam is verified by comparing the intensity values obtained from each sample for each beam. Generally, the fact that the beam intensity value is constant, that is, the beam intensity value is within the predetermined maximum fluctuation range, indicates that the reception of the beam signal is performed properly. On the other hand, a large difference between samples means that interference energy exists.
If the samples taken for a particular beam indicate that interference energy is present, the signal received for that particular beam is ignored. However, if the sample taken for this beam indicates proper reception of the beam signal and the minimum beam intensity value is greater than the detection threshold, then an obstacle has been detected. Represent. The data for each three-dimensional beam is processed similarly.

In a third embodiment of the present invention, the transmitted beam signal is modulated not by a simple square wave modulation but by a specific binary code having a fixed bit rate and repeating. Referring to FIG. 5, an exemplary embodiment of a binary modulation code is illustrated in comparison to continuous square wave modulation. Each three-dimensional beam is sampled only once per scan frame. In the data collection stage, the intensity of the individual beams is sampled while the binary modulation code of the received signal is detected. The detection of such a binary modulation code is performed by using a port pin of a CPU (Central Processing Unit) to detect the polarity (pola) of the received signal.
rity). If no binary modulation code is detected, the detected signal is determined to be from a source external to the system and a "no detection" level is stored for this beam. If the beam signal has the correct modulation code, a value representing the intensity of the beam is stored for the beam, as described above. The data processing steps are performed as usual, as described above. Although this specification describes the use of binary modulation codes, it will be apparent to those skilled in the art that other modulation codes (eg, frequency modulation codes) may be used.

[0034] The addition of three-dimensional sensing capabilities to door safety systems creates sensitivity to light and impulse noise from external sources, which renders certain prior art systems inoperable under various circumstances. Such situations include the use of a relay-type control device or a fire alarm system using strobe light in elevator facilities, the installation of a vehicle near an emergency vehicle beacon (ie, a hospital), and the use of a fluorescent lighting system. , And the like. The present invention provides a system that operates reliably in such an environment and therefore operates more safely and economically.

While a preferred embodiment of the invention has been described herein, it will be understood that modifications and variations are possible without departing from the scope of the invention as claimed.

[Brief description of the drawings]

FIG. 1 is a schematic partial front view of a system according to the present invention.

FIG. 2 is a schematic partial view of the components of the system according to FIG. 1;

FIG. 3 is a schematic partial plan view of the system according to FIG. 1;

FIG. 4 is a schematic partial plan view of the system according to FIG. 1;

FIG. 5 schematically illustrates a binary modulation code according to the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 Door safety system 12 Door passage 14 Hall passage 16 Elevator car 18 Wall 20 Wall 24 Hall passage door 26 Hall passage door 28 Elevator car door 30 Elevator car door 34 Threshold 38 Safety detection system 40 Transmitter row 42 Detector row 50 Transmitter wiring board 52 Transmitter lens substrate 46 Housing 48 Transparent cover 56 Three-dimensional transmitter lens 58 Curtain transmitter lens 60 Transmitter or light emitting diode (LE
D) 64 Transmitter light shielding plate 66 Detector row housing 68 Detector row cover 70 Detector wiring board 72 Detector lens board 76 Three-dimensional detector lens 77 Controller 78 Curtain detector lens 79 Door controller 80 Detector or photodiode 84 Detector shield 86 Field of view 96 Field of view 94 Detection zone

 ──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Terir Davreux. Morton United States of America, Arizona, Texas, N. Wide load 7745 F term (reference) 3F307 AA02 DA11 5J084 AA01 AB07 AD03 BA04 BA05 BA36 BA38 BB02 CA23 CA31 CA44

Claims (21)

[Claims] 1. A method for detecting an object in a detection zone using a plurality of pairs of three-dimensional energy emitters and receivers, the emitter transmitting an energy beam at a predetermined angle toward the object. And wherein the receiver senses an energy beam reflected from the object, sampling the reflected energy beam of the emitter / receiver pair a predetermined number of times to obtain a set of intensity signals indicative of the intensity of the reflected energy; Comparing the value of the minimum intensity signal of the set of intensity signals to a predetermined threshold; and generating an object detection signal when the value of the minimum intensity signal reaches a predetermined threshold. And a method comprising: Determining the range of variation of the set of intensity signals; comparing the range of variation of the set of intensity signals with a predetermined maximum variation range; Generating the object detection signal if it is within the predetermined maximum variation range. 3. modulating the transmitted energy beam of the emitter / receiver pair with a predetermined modulation code; detecting the presence of the modulation code with respect to the sampled energy beam; and detecting the presence of the modulation code. Generating an object detection signal when the event occurs. Modulating a transmitted energy beam of the emitter / receiver pair with a predetermined modulation code; detecting the presence of the modulation code with respect to the sampled energy beam; and detecting the presence of the modulation code. Generating an object detection signal in the event of a failure. 5. The sampling step further comprises: sampling the reflected energy beam to obtain a resulting signal; and integrating the signal resulting from the sampling for a predetermined time to obtain an integrated output signal. Comparing the integrated output signal with a predetermined minimum detection threshold value, and generating an integration end signal when the integrated output signal reaches the minimum detection threshold value. The method of claim 1, wherein 6. A method of providing a plurality of pairs of curtain energy emitters and receivers, wherein said emitters transmit a curtain energy beam directly to each corresponding receiver; Sampling the transmitted energy beam to obtain a curtain signal indicating that no object is present in the curtain energy beam; and a second object detection signal if the curtain signal is interrupted. Generating the method. 2. The method of claim 1, further comprising: 7. The emitter / receiver pair further comprises:
2. The method of claim 1 comprising providing all the pairs of energy emitters and receivers of all emitter / receiver pairs. 8. The method of claim 1, wherein said plurality of pairs of three-dimensional energy emitters and receivers are mounted on opposing doors of an elevator car. 9. The method of claim 3, wherein the modulation code is a binary code. 10. A method of detecting an object in a detection zone using a plurality of pairs of three-dimensional energy emitters and receivers, the emitter transmitting an energy beam at a predetermined angle toward the object. And wherein the receiver senses an energy beam reflected from the object, sampling the reflected energy beam of the emitter / receiver pair a predetermined number of times to obtain a set of intensity signals indicating the intensity of the reflected energy. Determining the variation range of the set of intensity signals; comparing the variation range of the set of intensity signals with a predetermined maximum variation range; and wherein the variation range of the set of intensity signals is the predetermined maximum variation. Generating an object detection signal if it is within the range. 11. Modulating the transmitted energy beam of the emitter / receiver pair with a predetermined modulation code; detecting the presence of the modulation code with respect to the sampled energy beam; detecting the presence of the modulation code 11. The method of claim 10, further comprising: generating an object detection signal when performed. 12. A method for detecting an object in a detection zone using a plurality of pairs of three-dimensional energy emitters and receivers, the emitter transmitting an energy beam at a predetermined angle toward the object. Wherein the receiver senses an energy beam reflected from the object, wherein the receiver modulates the transmitted energy beam of the emitter / receiver pair with a predetermined modulation code; Detecting the presence of the modulation code with an error detection signal, and generating an object detection signal when the modulation code is detected. 13. A system for detecting an object in a detection zone, the system comprising a plurality of pairs of three-dimensional energy emitters and receivers, the emitter directing an energy beam at an angle to the object. Wherein the receiver senses an energy beam reflected by the object, and the system further comprises a controller responsive to signals from the receiver and having data acquisition and data processing circuitry. The data collection and data processing circuit samples the reflected energy beam of the emitter / receiver pair a predetermined number of times to obtain a set of intensity signals indicating the intensity of the reflected energy; Comparing the value of the intensity signal with a predetermined threshold value, wherein the value of the minimum intensity signal reaches the predetermined threshold value System characterized in that functions to generate an object detection signal when the. 14. The data collection and data processing circuit further determines a variation range of the set of intensity signals, compares the variation range of the set of intensity signals with a predetermined maximum variation range, 14. The system of claim 13, further comprising circuitry operable to generate an object detection signal when the set of variation ranges is within the predetermined maximum variation range. 15. The data collection / data processing circuit,
Further, the transmission energy beam of the emitter / receiver pair is modulated with a predetermined modulation code, the presence of the modulation code is detected with respect to the sampled energy beam, and when the presence of the modulation code is detected, the object detection signal is generated. 14. The system of claim 13, further comprising circuitry operative to generate. 16. The data collection / data processing circuit,
Further, the transmission energy beam of the emitter / receiver pair is modulated with a predetermined modulation code, the presence of the modulation code is detected for the sampled energy beam, and an object detection signal is generated when the presence of the modulation code is detected. 15. The system of claim 14, operable to: 17. The system of claim 13, wherein said plurality of pairs of three-dimensional energy emitters and receivers are mounted on opposing doors of an elevator car.
The described system. 18. The data collection / data processing circuit,
Further comprising a microprocessor responsive to a signal from the receiver, the microprocessor comprising a memory for storing a signal including a signal defining an execution program for generating an object detection signal. 14. The system according to claim 13, wherein: 19. A system for detecting an object within a detection zone, comprising a plurality of pairs of three-dimensional energy emitters and receivers, the emitter directing an energy beam at a predetermined angle to the object. Wherein the receiver senses an energy beam reflected by the object, and the system further comprises a controller responsive to a signal from the receiver and having data acquisition and data processing circuitry. The data collection / data processing circuit samples the reflected energy beam of the emitter / receiver pair a predetermined number of times to obtain a set of intensity signals indicating the intensity of the reflected energy, and obtains a variation range of the set of intensity signals. Determining the variation range of the set of intensity signals with a predetermined maximum variation range; A system operable to generate an object detection signal when a motion range is within the predetermined maximum variation range. 20. The data collection / data processing circuit,
Further, the transmission energy beam of the emitter / receiver pair is modulated with a predetermined modulation code, the presence of the modulation code is detected with respect to the sampled energy beam, and the object detection is performed when the presence of the modulation code is detected. The system of claim 19, further comprising circuitry operative to generate a signal. 21. A system for detecting an object within a detection zone, comprising: a plurality of pairs of three-dimensional energy emitters and receivers, the emitter directing an energy beam at a predetermined angle to the object. Wherein the receiver senses an energy beam reflected by the object, and the system further comprises a controller responsive to a signal from the receiver and having data acquisition and data processing circuitry. The data collection and data processing circuit modulates the transmitted energy beam of the emitter / receiver pair with a predetermined modulation code, and detects the presence of the modulation code with respect to the sampled energy beam of the emitter / receiver pair; Function to generate an object detection signal when a modulation code is detected System which is characterized.