HK1085714A - Optically synchronized safety detection device for elevator sliding doors - Google Patents

Description

Optical synchronous safety detection device of elevator sliding door

Background

Technical Field

The present invention relates to an optically synchronized safety detection system for sliding elevator doors and a method for operating such a system.

Prior Art

Many elevator door detection systems currently in operation include a control unit, an emitter door unit (IR emitter array) and a detector door unit (IR receiver array). The gate unit power conditioning and supply and control and synchronization functions are provided by the control unit through the multi-wire cable assembly. While such systems have proven to be fairly reliable, systems produced in this manner tend to be expensive to build and operate.

Cost analysis of these current detection systems has shown that the overall detection system cost can be reduced by more than 60% if many separate control units can be eliminated. However, in order to not use the control unit, its function needs to be assumed by the gate unit. Due to the limited size of the door units, the control and power supply functions cannot be simply moved to the individual door units.

Cost reduction may be achieved by eliminating the need for electrical communication between the various gate units, simplifying the interconnection cables, eliminating the need for buffering and associated protection circuitry. However, scanning elevator entrances and employing separate emitter and detector arrays requires a very complex scanning sequence. The operation or function of the emitter array and the detector array must be carefully coordinated and synchronized. Since there is already a form of unidirectional connection between the emitter door unit and the detector door unit, i.e. in the form of energy used to scan the elevator entrance, it would be advantageous if a method could be devised to use this energy to complete the required connection between the door units. However, the scanning energy generated by the transmitter units of any single source is discontinuous and therefore presents a problem of synchronization between the transmitter and receiver units.

Therefore, there is a need for an elevator door detection system in which power and control functions are assigned to each door unit and are customized for the individual needs of each system. It has further proved advantageous to eliminate the need for electrical communication between the gate units.

Disclosure of Invention

It is therefore an object of the present invention to provide an optically synchronized safety detection system for sliding elevator doors and a method of operating the same.

According to the invention, the safety detection system of a gate arrangement comprises a plurality of linearly arranged emitters, each emitter being adapted to be activated (activated) to emit an energy beam; and a plurality of receivers arranged in a line, each receiver corresponding to one of the emitters and adapted to receive the energy beam generated from the corresponding emitter, wherein each receiver is individually activated prior to receiving the energy beam in a scanning order, each emitter is individually activated to emit the energy beam in the scanning order, and each activated receiver is deactivated upon receiving the energy beam, while the next receiver in the scanning order is activated.

According to the invention, a method for safety monitoring in a door arrangement comprises the following steps: positioning emitters in a line along a first vertical surface; positioning a plurality of receivers in a line along a second vertical surface, wherein each receiver corresponds to one of the plurality of transmitters; activating a receiver in a scanning order; activating an emitter to emit an energy beam in a scan sequence; receiving an energy beam with one receiver being activated, deactivating the activated receiver upon receipt of the energy beam, and activating a next receiver determined in the scanning order; activating a next emitter in the scan order to emit an energy beam; the steps are repeated until each transmitter and each receiver are activated in the scan order.

Drawings

FIG. 1 is a schematic diagram of a security detection system of the present invention;

FIG. 2 is a schematic diagram of the security detection system of the present invention after detecting a beam break.

Description of The Preferred Embodiment

The present invention describes a two-dimensional elevator door unit detector in which power and control functions are assigned to each door unit and no electrical communication is required between the door units.

The apparatus of the present invention includes a series of transmitters on the leading edge of a first door and a series of receivers on the leading edge of a second door. A first controller controls the sequence of activation of each transmitter and a second controller controls the activation of each individual receiver to detect the beam or beams emitted by the transmitters. The second controller also provides a signal to the gate controller to cause the gate to change direction once the signal is lost or an interruption in the transmitted beam is detected.

In the event of such loss of signal or detection of an interruption, the gates will not close again until a complete scan is completed with no loss of signal or detection of an interruption. The scanning patterns of the transmitter and receiver are controlled independently of each other. The transmitter is switched on and off in a known scanning pattern and the receiver is enabled to receive in a pattern matching the transmitter pattern but using energy detected from the transmitter to synchronize the scanning pattern of the receiver with the scanning pattern of the transmitter. This eliminates the need for any type of electrical connection between the transmitter array and the receiver array, as will be described in more detail below.

Fig. 1 shows an elevator door detection system of the present invention. A plurality of transmitters 11 are positioned vertically along a leading edge 23 of the first door 19 and a plurality of receivers 17 are positioned vertically along a leading edge 25 of the second door 21 opposite the transmitters 11. In a preferred embodiment to be described below, each transmitter 11 has a corresponding receiver 15 at the same horizontal position as it. Each respective pair of one receiver 17 and one transmitter 11 forms a transmitter/receiver pair. The figure shows an image of the energy signal 23 emitted by a single emitter. It should be noted that the energy signal 23 emitted by a single emitter is in contact with more than one receiver 17.

The single emitter 11 is switched on to form an active emitter 13 and a receiver 17 opposite the emitter, the active receiver 15 being switched on and held until it detects an energy signal 23. This active receiver 15 is then deactivated and the next receiver in the scanning order is allowed to receive. As used herein, "scan order" refers to the order in which the transmitters 11 and receivers 17 are activated during the completion of a normal or diagnostic scan. When the next transmitter 11 in the sequence is switched on to become the active transmitter 13 and the optical path to the active receiver 15 is not blocked, the received energy signal 23 triggers the next receiver 17 in the sequence to be activated and so on. This pattern will be repeated for each transmitter/receiver pair. This scanning sequence may be hardwired to each of the receiver 17 and transmitter 11 arrays or, preferably, stored in respective controllers 31, 33 associated with the first gate 19 and the second gate 21.

It can be seen that each active transmitter 13 produces a fairly compact light pattern containing the energy signal 23, which can illuminate more than one receiver 17 at a time. Thus, in a preferred embodiment, the scanning sequence used to turn on or off the emitters 11 is such that no two consecutive activated emitters 13 illuminate the same receiver 17.

An example of a scanning sequence to achieve this is described below, although various other scanning sequences may be used to effectively achieve the objects of the present invention. In this example, 26 emitters 11 are taken as an example (the 1 st to 26 th emitters are arranged from top to bottom). Assume that 26 emitters in a scan sequence (the first emitter 11 at the top of the first gate 19 and the 26 th emitter 11 at the bottom of the first gate 19) are activated in the following order: 1. 14, 2, 15, 3, 16, and on to 13, 26. Likewise, the receivers 17 are activated in the same order. In this example, the energy signal 23 contacts the activation receiver 15 at the same level as the activation transmitter 13 and five receivers on each side. However, as a result of the scanning sequence described herein, subsequent active receivers will not incorrectly receive an energy signal 23 from the transmitter 13.

This will be apparent from the following description. As shown, the 16 th active transmitter 13 is transmitting an energy signal 23, which is sensed by the 16 th active receiver 15 and the 11 th to 15 th and 17 th to 21 th receivers 17. Upon receipt of the transmitted energy signal 23, the next receiver 17 is activated to become the active receiver 15, in this case the 4 th active receiver 15. Note that the 4 th receiver 17 is not included in the 11 th to 21 st receivers 17, and thus the transmitted energy signal 23 does not contribute to it.

Each activation receiver 15 waits for a finite predetermined period of time for energy to be emitted from the corresponding activation transmitter 13, or transmitter whose energy signal 23 may illuminate the activation receiver 15. Once the transmitted energy is detected by the currently active receiver 15, the connection to that receiver (or beam) is entered and the next receiver 17 in the scan sequence is changed to the active receiver 15. If no emission energy is detected within a certain maximum waiting period (which should be long enough to ensure that the expected energy should be reached), a beam interrupt is input and a reverse signal is sent to the door operator 37 while the system 10 is parked (park) (i.e. the "parked" beam/receiver 21, in this case the bottom receiver 17, is activated), as shown in fig. 2. In a preferred embodiment, the gates 19, 21 are opened upon receipt of the reverse signal.

The system 10 then waits for "first energy" to be received by the parking receiver 21. When energy is detected, the synchronization state is considered "ready" while the top receiver is activated, as shown in fig. 2. When the top receiver detects energy, a synchronization state has been established between the emitter unit and the detector, while normal scanning resumes. It is ensured that this synchronization state is established because even if the bottom or parked receiver 20 is not able to receive energy from the transmitter 11 that does not really correspond to the parked receiver 20, by the time energy is received by the bottom/parked receiver 20, the order of the transmitters has advanced far enough to ensure that the top receiver does not receive any energy before the transmitter unit resumes its scanning order from the top.

Once a synchronization state is established between the transmitter and receiver arrays, the normal scan sequence begins. If the entire scan sequence is successfully scanned without beam interruption, the reverse signal to the door operator is cleared and normal scanning continues as previously described.

As can be seen from the figure and indicated above, each transmitter 11 may illuminate several receivers 17. Thus, each emitter in the scan order must be separated far enough from the emitter that precedes it in the sequence or the next emitter in the sequence so that no detector can "see" the energy emitted from any two consecutive emitters in the sequence. Alternatively, if energy is detected from an incorrect transmitter 11 in the sequence (i.e. a transmitter not directly opposite the parked receiver 20) while the receiver is parked waiting for the synchronisation state to be established or re-established, the scanning sequence is designed such that at least one (falsely composed) beam will "break" before the entire scan is completed, causing a "re-park and synchronisation" operating state, whilst the originally present reverse signal remains active. A better way to achieve this is to add a perturbation to the scan sequence. For example, after completing the scan sequence described above as ". 12, 25, 13, 26", a short additional sequence, such as "1, 26, 1, 26", may be added.

In a preferred embodiment, some additional spurious synchronization loop perturbations are added to the scan sequence to eliminate the possibility of creating an infinite loop. It is particularly important to avoid the occurrence of such situations: the "breaking" of one "false" sync state directly results in the "breaking" of another "false" sync state, which returns to some "false" sync state that was originally present, so that many "false" sync cycles occur and true synchronization cannot be achieved. In this case, since the detection system 10 continues to indicate a "fault," the reverse signal will never fail and the doors will continue to be in the open position.

Although the above description refers to a detection system 10 comprising two doors 19, 21, this is not a limitation of the invention. For example, the invention may include a detection system 10 comprising a single door with a leading edge that, in the closed position, contacts a vertical wall along which a number of receivers 17 or transmitters 11 of the invention may be mounted vertically.

It is apparent that there has been provided in accordance with the present invention an optically synchronized safety detection system for sliding elevator doors that fully satisfies the objects, means, and advantages set forth above. Although the present invention has been described with reference to specific embodiments, other alternatives, modifications, and variations will become apparent to those skilled in the art having read the foregoing description. Accordingly, such alternatives, modifications, and variations are considered to be within the broad scope of the following claims.

Claims (17)

1. A security detection system for a door apparatus, comprising:

a plurality of linearly arranged emitters, each emitter adapted to be activated to emit an energy beam; and

a plurality of linearly arranged receivers, each receiver corresponding to one of the emitters and adapted to receive one of the energy beams emitted from a respective one of the emitters;

wherein each receiver is individually activated prior to receiving the energy beam in a scan order, wherein each transmitter is individually activated in the scan order to transmit the energy beam, and wherein each activated receiver is deactivated upon receiving the energy beam while a next receiver in the scan order is activated.

2. The security detection system of claim 1, wherein said plurality of emitters are arranged in a line disposed at a leading edge of the door.

3. The security detection system of claim 1, wherein said plurality of emitters are vertically disposed in a line.

4. The security detection system of claim 3 wherein said door comprises an elevator door.

5. The security detection system of claim 1, wherein said linearly disposed receivers are disposed at a leading edge of the door.

6. The security detection system of claim 5 wherein said receivers are vertically disposed.

7. The security detection system of claim 4 wherein said door comprises an elevator door

8. The safety detection system of claim 1 wherein said energy beam comprises infrared light.

9. The safety detection system of claim 1 wherein each of said receivers is adapted to wait a predetermined period of time for receipt of said energy beam.

10. The safety detection system of claim 9 wherein each of said receivers is adapted to acknowledge a beam interruption without having received said energy beam for said predetermined period.

11. A method of security detection of a door assembly, comprising the steps of:

a) positioning emitters in a line along a first vertical surface;

b) positioning a plurality of receivers in a line along a second vertical surface, wherein each receiver corresponds to one of the plurality of transmitters;

c) activating one of the plurality of receivers in a scan order;

d) activating one of the plurality of emitters in a scan order to emit an energy beam;

e) receiving the energy beam with an activated one of the plurality of receivers; deactivating the activated receiver upon receipt of the energy beam and activating a next one of the plurality of receivers determined in the scan order;

f) activating a next one of the plurality of emitters in the scan order to emit the energy beam; and

g) repeating steps e through f until each of the plurality of transmitters and each of the plurality of receivers are activated in the scan order.

12. The method of claim 11, wherein positioning the plurality of launchers in a line along the first vertical surface comprises positioning the plurality of launchers along an edge of an elevator door.

13. The method of claim 11, wherein positioning the plurality of receivers in a line along the vertical surface comprises positioning the plurality of receivers along an edge of an elevator door.

14. The method of claim 11, further comprising the additional step of constructing said scan sequence to synchronize said plurality of transmitters and said plurality of receivers.

15. A method of security detection of a door assembly, comprising the steps of:

a) positioning a plurality of emitters in a line along a first vertical surface;

b) positioning a plurality of receivers in a line along a second vertical surface, wherein each receiver corresponds to one of the plurality of transmitters;

c) activating one of the plurality of receivers in a scan order;

d) activating one of the plurality of emitters in the scan order to emit an energy beam;

e) receiving the energy beam with an activated one of the plurality of receivers; deactivating one of the plurality of receivers that has been activated upon receipt of the energy beam and activating a next one of the plurality of receivers determined in the scan order;

f) activating a next one of the plurality of emitters in the scan order to emit the energy beam;

g) repeating steps e) through f) until each of the plurality of transmitters and each of the plurality of receivers are activated in the scan order and waiting a predetermined time period for the activated one of the plurality of receivers to receive the energy beam; and

h) confirming a beam interruption if the activated one of the plurality of receivers does not receive the energy beam within the predetermined time period.

16. The method of claim 15, further comprising the additional step of opening said elevator door after said energy beam is confirmed.

17. An elevator door safety detection system comprising:

a series of transmitters on the first door;

a series of receivers on the second door;

a first means for controlling the transmitter activation sequence;

second means for activating the receiving volume to detect the beam emitted by the transmitter;

a third device for controlling the door; and

the second means provides a signal to the gate control means to invert the gate upon at least one of a loss of signal and detection of a beam break.