JP7779225B2 - Counterweights and impact mitigation devices - Google Patents

Description

This disclosure relates to a counterweight and a collision mitigation device.

Patent Document 1 discloses an example of an elevator alarm system. In this system, a beacon detects the proximity of a maintenance worker to a counterweight. When the proximity of a maintenance worker to the counterweight is detected, an audio alarm is sounded.

Japanese Patent Application Laid-Open No. 2019-59620

However, with the alarm system described in Patent Document 1, there is a possibility that a maintenance worker performing maintenance work may not notice the audio alarm. In this case, there is a risk that the maintenance worker may collide with the counterweight.

This disclosure is directed to solving these problems. This disclosure provides a counterweight and a collision mitigation device that mitigate the impact of a maintenance worker colliding with the counterweight.

The counterweight according to the present disclosure is disposed in a hoistway with its back surface facing the inner wall of the hoistway, and travels in the hoistway guided by a guide rail with its longitudinal direction in the up-down direction. It is equipped with a distance sensor that measures the distance to a maintenance worker located below the lower end of the counterweight, a detection unit that detects that the maintenance worker is approaching closer than a predetermined first threshold when the distance measured by the distance sensor is shorter than the first threshold, and an airbag that is disposed at the lower end of the counterweight and deploys downward when the detection unit detects that the maintenance worker is approaching closer than the first threshold.

The collision mitigation device disclosed herein is attached to the lower end of a counterweight that travels along a guide rail with its back facing the inner wall of the elevator shaft, and includes a distance sensor that measures the distance to a maintenance worker located below the lower end of the counterweight, a detection unit that detects that the maintenance worker is approaching closer than a predetermined first threshold when the distance measured by the distance sensor is shorter than the first threshold, and an airbag that deploys downward when the detection unit detects that the maintenance worker is approaching closer than the first threshold.

The counterweight or impact mitigation device disclosed herein mitigates the impact of a maintenance worker colliding with the counterweight.

1 is a configuration diagram of an elevator according to a first embodiment. FIG. 2 is a front view of the counterweight according to the first embodiment. 1 is a configuration diagram of a collision mitigation device according to a first embodiment. 3A to 3C are diagrams illustrating an example of deployment of an airbag according to the first embodiment. 4 is a flowchart showing an example of the operation of the collision mitigation device according to the first embodiment. 1 is a hardware configuration diagram of a main part of a collision mitigation device according to a first embodiment. FIG. 10 is a front view of a counterweight according to a first modified example of the first embodiment. FIG. 10 is a side view of a counterweight according to a second modified example of the first embodiment. 10A and 10B are diagrams illustrating an example of deployment of an airbag according to a second embodiment.

Modes for implementing the subject matter of the present disclosure will be described with reference to the accompanying drawings. In each drawing, the same or corresponding parts will be assigned the same reference numerals, and redundant explanations will be appropriately simplified or omitted. Note that the subject matter of the present disclosure is not limited to the following embodiments, and any component of the embodiments may be modified or omitted within the scope of the spirit of the present disclosure.

Embodiment 1.
FIG. 1 is a configuration diagram of an elevator 1 according to the first embodiment.

The elevator 1 is applied to, for example, a building 2 having multiple floors. A hoistway 3 for the elevator 1 is provided in the building 2. The hoistway 3 is a vertically long space spanning multiple floors. The hoistway 3 is a space surrounded by a vertically long interior wall 4. Note that the interior wall 4 of the hoistway 3 does not have to be flat. Equipment for the elevator 1 may be provided on the interior wall 4 of the hoistway 3. A landing 5 adjacent to the hoistway 3 is provided on each floor. A landing door 6 for the elevator 1 is provided at the landing 5 on each floor. The landing door 6 separates the landing 5 from the hoistway 3. A pit 7 is provided at the bottom of the hoistway 3. During maintenance on the elevator 1, maintenance work by a maintenance worker M is performed, for example, in the pit 7. A pit light 8 is provided in the pit 7 to illuminate the pit 7 during maintenance on the elevator 1. The pit light 8 is an example of a lighting device.

The elevator 1 comprises a hoist 9, a main rope 10, a car 11, a counterweight 12, a buffer 13, and a control panel 14.

The hoisting machine 9 includes a motor that generates driving force and a sheave that rotates due to the driving force generated by the motor. The hoisting machine 9 is disposed, for example, at the top or bottom of the hoistway 3. Alternatively, if a machine room is provided in the elevator 1, for example, above the hoistway 3, the hoisting machine 9 may be disposed in the machine room.

The main rope 10 is a rope that supports the load of the car 11 and counterweight 12 in the hoistway 3. The main rope 10 is wound around the sheave of the hoisting machine 9. The main rope 10 supports the load of the car 11 on one side of the sheave of the hoisting machine 9. The main rope 10 supports the load of the counterweight 12 on the other side of the sheave of the hoisting machine 9. The main rope 10 moves so that it is wound up onto the sheave of the hoisting machine 9 or unwound from the sheave of the hoisting machine 9 as the sheave of the hoisting machine 9 rotates.

The car 11 is a device that transports passengers and the like between multiple floors of the building 2 by traveling up and down the hoistway 3. The car 11 is equipped with a car door 15. The car door 15 separates the interior of the car 11, where passengers board, from the exterior of the car 11. When the car 11 stops at a floor, the car door 15 opens and closes in conjunction with the landing door 6 provided at the landing 5 of that floor. The counterweight 12 is a device that balances the loads acting on both sides of the sheave of the hoisting machine 9 between the car 11 and the counterweight 12. The counterweight 12 is positioned in the hoistway 3 so that its back surface faces the inner wall 4 of the hoistway 3. When performing maintenance on the elevator 1, a maintenance worker M performing maintenance work in the pit 7 performs the work in the space forward of the counterweight 12. The car 11 and counterweight 12 travel in opposite directions up and down the hoistway 3 in conjunction with the main rope 10, which is moved by the motor and sheave of the hoisting machine 9.

The buffer 13 is located in the pit 7 below each of the car 11 and counterweight 12. The buffer 13 is a device that reduces the impact when the car 11 or counterweight 12 collides with the bottom of the elevator shaft 3.

The control panel 14 is a device that controls the operation of the elevator 1. The control of the operation of the elevator 1 by the control panel 14 includes, for example, the running of the car 11. The control panel 14 is located, for example, at the top or bottom of the hoistway 3. Alternatively, if a machine room is provided, the control panel 14 may be located in the machine room.

Figure 2 is a front view of the counterweight 12 according to embodiment 1.

A pair of guide rails 16 with the vertical direction as the longitudinal direction are arranged in the elevator shaft 3. The pair of guide rails 16 are arranged parallel to each other. Each guide rail 16 is a device that guides the movement of the counterweight 12. The pair of guide rails 16 are arranged on both the left and right sides of the counterweight 12. In other words, the counterweight 12 is arranged between the pair of guide rails 16.

The counterweight 12 comprises a counterweight frame 17, a counterweight block 18, a counterweight guide 19, and a collision mitigation device 20.

The weight frame 17 is a frame-shaped device that forms the outer periphery of the counterweight 12. The shape of the weight frame 17 is, for example, rectangular. In this example, the main rope 10 on the counterweight 12 side is attached to the upper edge of the weight frame 17. The weight frame 17 has a spacer 21 at its lower end. The spacer 21 is the part that comes into contact with the buffer 13 at the lower end of the counterweight 12 when the counterweight 12 collides with the bottom of the hoistway 3. In this example, the spacer 21 is located in the horizontal center at the lower end of the weight frame 17.

The weight block 18 is loaded into the weight frame 17 so that the weight of the counterweight 12 can be adjusted.

The weight guide 19 is a device that receives guidance in the travel direction of the counterweight 12 from the guide rail 16. In this example, the weight guide 19 is attached to the outside of each of the four corners of the weight frame 17. The weight guide 19 comes into contact with the guide rail 16, thereby receiving contact from the guide rail 16.

The collision mitigation device 20 is a device that mitigates the impact of a collision between the maintenance worker M and the counterweight 12. The collision mitigation device 20 is located at the lower end of the counterweight 12. The collision mitigation device 20 may be an internal device that is integrated with the counterweight 12 itself, or an external device that is attached to an existing counterweight from the outside. In this example, the collision mitigation device 20 is integrated with the lower edge of the counterweight frame 17.

FIG. 3 is a configuration diagram of the collision mitigation device 20 according to the first embodiment.
In FIG. 3, the counterweight 12 is shown as seen from below.

The weight guide 19 of the counterweight 12 includes guide rollers 22. The guide rollers 22 are rollers that contact the guide rail 16. The guide rollers 22 move while rotating on the surface of the guide rail 16 as the counterweight 12 travels. In this example, each weight guide 19 includes three guide rollers 22 that contact the guide rail 16 from three directions.

The collision mitigation device 20 includes an airbag 23, a distance sensor 24, an ejection device 25, an alarm device 26, a power generator 27, a battery 28, and a control device 29.

The airbag 23 is a device that deploys by inflating downward when it receives a control signal indicating deployment. During deployment, the airbag 23 inflates so that it shoots out from an outlet provided in the impact mitigation device 20. The outlet of the airbag 23 faces downward. The airbag 23 may be deployed by gas suddenly generated by a chemical reaction, or by compressed air, or by gas blown in from a fan (not shown). In this example, the outlets of the airbag 23 are located on both the left and right sides of the spacer 21.

The distance sensor 24 is a sensor that measures the distance to an external object without contact. The distance sensor 24 is, for example, a laser rangefinder. Here, the laser rangefinder may measure distance using any method, such as triangulation or ToF (Time of Flight). Furthermore, for example, a ToF laser rangefinder may measure ToF using either a phase difference method or a pulse method. Alternatively, the distance sensor 24 may be a rangefinder that uses ultrasonic waves. The distance sensor 24 may also be a stereo camera. The distance sensor 24 may also be a ToF camera. The distance sensor 24 measures the distance to the maintenance worker M, who is located below the lower end of the counterweight 12. In this example, the distance sensors 24 are positioned on both the front and rear sides of the airbag 23's discharge port. The direction in which the distance sensor 24 measures the distance is, for example, directly below the counterweight 12 or in a direction inclined toward the front from directly below the counterweight 12.

The ejection device 25 is a device that ejects gas from an ejection port when it receives a control signal indicating ejection. The ejection port of the ejection device 25 faces downward. The ejection device 25 may eject air using a fan or the like, or may eject compressed air or the like. In this example, the ejection port of the ejection device 25 is located adjacent to the discharge port of the airbag 23. The ejection ports of the ejection device 25 are located, for example, on the outside to the left and right of the discharge port of the airbag 23.

The alarm device 26 is a device that, when receiving a warning signal indicating an alarm, issues the alarm as an audio warning. The alarm device 26 includes, for example, a speaker. The audio warning may be, for example, an announcement indicating the content of the alarm, or a buzzer sound.

The power generator 27 is a device that generates electricity through the rotation of a rotor attached to the counterweight 12. The rotor rotates in conjunction with the movement of the counterweight 12. The rotor is, for example, the guide roller 22 of the counterweight guide 19. The power generator 27 generates electricity through the rotation of, for example, all or some of the guide rollers 22 attached to the counterweight 12.

The battery 28 is a device that stores power and supplies the stored power to other devices. The battery 28 stores the power generated by the power generation device 27. The battery 28 supplies power to some or all of the airbags 23, distance sensors 24, ejection devices 25, warning devices 26, power generation device 27, and control device 29 of the collision mitigation device 20.

The control device 29 is a device that processes information in the collision mitigation device 20. The control device 29 includes a detection unit 30 and a warning unit 31.

The detection unit 30 is a component equipped with a function for detecting the approach of maintenance worker M based on the distance measured by the distance sensor 24, etc. When the distance measured by the distance sensor 24 is shorter than the first threshold, the detection unit 30 detects that maintenance worker M is approaching closer than the first threshold. Furthermore, when the distance measured by the distance sensor 24 is shorter than the second threshold, the detection unit 30 detects that maintenance worker M is approaching closer than the first threshold. Here, the first threshold and second threshold are preset thresholds for distance. The second threshold is set to a distance longer than the first threshold. The first threshold is set to a distance of, for example, 0.5 m. In this case, the second threshold is set to a distance of, for example, 1.5 m. When the detection unit 30 detects that maintenance worker M is approaching closer than the first threshold, it outputs a control signal to the airbag 23, indicating deployment.

The detection unit 30 may stop detecting the approach of the maintenance worker M when the counterweight 12 is located in a position below the lower end of the counterweight 12 where it is not expected that the maintenance worker M would be present. For example, if the counterweight 12 is located in a position where the distance from the lower end of the counterweight 12 to the bottom of the hoistway 3 is shorter than the height of the maintenance worker M, it is not normally expected that the maintenance worker M will accidentally enter below the counterweight 12. Therefore, when the counterweight 12 is located in such a range, the detection unit 30 may stop detecting the approach of the maintenance worker M regardless of the distance measured by the distance sensor 24. For example, the detection unit 30 may stop detecting the approach of the maintenance worker M when the counterweight 12 is located in a position where the distance from the lower end of the counterweight 12 to the bottom of the hoistway 3 is shorter than the first threshold or the second threshold. This makes it less likely that the detection unit 30 will mistakenly detect the approach of the counterweight 12 to the bottom of the hoistway 3 as the approach of maintenance worker M when the distance sensor 24 is measuring the distance to the bottom of the hoistway 3. If the detection unit 30 can communicate with the control panel 14 of the elevator 1 via wired or wireless communication, it may obtain the position of the counterweight 12 from the control panel 14. The detection unit 30 may also obtain the position of the counterweight 12 using a camera or other sensor (not shown).

The warning unit 31 is a part equipped with a function to output a warning signal to warn the maintenance worker M. The warning unit 31 outputs a warning signal when the detection unit 30 detects that the maintenance worker M is closer than the second threshold. The warning unit 31, for example, outputs a control signal indicating ejection to the ejection device 25 as a warning signal. The warning unit 31, for example, outputs a warning signal indicating an alarm to the alarm device 26. The warning unit 31, for example, outputs a control signal to a lighting device such as a pit light 8 to turn on or blink as a warning signal. Note that if the collision mitigation device 20 itself is equipped with a lighting device (not shown), the warning unit 31 may output the control signal to the lighting device as a warning signal.

FIG. 4 is a diagram showing an example of deployment of the airbag 23 according to the first embodiment.
In FIG. 4, the counterweight 12 is shown viewed from the side.

When a control signal indicating deployment is received, the airbag 23 deploys by inflating downward from the lower end of the counterweight 12. In this example, the airbag 23 deploys downward and diagonally forward. In other words, the airbag 23 deploys in a direction away from the inner wall 4 of the elevator shaft 3.

The airbags 23 inflate downward from the lower end of the counterweight 12, so even if a maintenance worker M below the counterweight 12 collides with it, the impact of the collision can be mitigated by the airbags 23 acting as a shock absorber. Furthermore, because the airbags 23 deploy in a direction away from the inner wall 4 of the elevator shaft 3, the maintenance worker M is pushed away to the side of the pit 7 where there is more space. This prevents the maintenance worker M from colliding with the counterweight frame 17 or other objects.

Figure 5 is a flowchart showing an example of the operation of the collision mitigation device 20 according to embodiment 1.

In step S1, the distance sensor 24 measures the distance to the maintenance worker M working in the pit 7. Then, processing by the collision mitigation device 20 proceeds to step S2.

In step S2, the detection unit 30 determines whether the distance measured by the distance sensor 24 is shorter than the first threshold. If the determination result is Yes, the processing of the collision mitigation device 20 proceeds to step S3. On the other hand, if the determination result is No, the processing of the collision mitigation device 20 proceeds to step S4.

In step S3, the detection unit 30 outputs a control signal indicating deployment to the airbag 23. The airbag 23 deploys by inflating downward based on the input control signal. Here, if the collision mitigation device 20 can communicate with the control panel 14 of the elevator 1 via wired or wireless communication, the detection unit 30 may output a control signal to stop the elevator 1 to the control panel 14. Upon receiving this control signal, the control panel 14 stops the elevator 1. The control panel 14 may then restrict restarting the elevator 1 until a manual reset operation is performed, for example, by maintenance worker M. After the airbag 23 is deployed, the operation of the collision mitigation device 20 ends.

In step S4, the detection unit 30 determines whether the distance measured by the distance sensor 24 is shorter than the second threshold. If the determination result is Yes, the processing of the collision mitigation device 20 proceeds to step S5. On the other hand, if the determination result is No, the processing of the collision mitigation device 20 proceeds to step S1.

In step S5, the detection unit 30 outputs a control signal indicating a warning to the warning unit 31. The warning unit 31 outputs the warning signal based on the input control signal. The warning unit 31 outputs the warning signal to, for example, the alarm device 26, the pit light 8, and the ejection device 25. The alarm device 26 warns the maintenance staff M by emitting an audio warning based on the input warning signal. The pit light 8 warns the maintenance staff M by lighting up or flashing based on the input warning signal. The ejection device 25 warns the maintenance staff M by ejecting gas based on the input warning signal. Then, processing of the collision mitigation device 20 proceeds to step S1.

As described above, the counterweight 12 according to the first embodiment is disposed in the hoistway 3 with its back surface facing the inner wall 4 of the hoistway 3. The counterweight 12 travels in the hoistway 3 while being guided by a guide rail 16 whose longitudinal direction is the up-down direction. The counterweight 12 is equipped with a collision mitigation device 20. The collision mitigation device 20 includes a distance sensor 24, a detection unit 30, and an airbag 23. The distance sensor 24 measures the distance from the lower end of the counterweight 12 to a maintenance worker M located below. The detection unit 30 detects that the maintenance worker M is approaching closer than the first threshold when the distance measured by the distance sensor 24 is shorter than a first threshold. The first threshold is a preset distance threshold. The airbag 23 is disposed at the lower end of the counterweight 12. The airbag 23 deploys downward when the detection unit 30 detects that the maintenance worker M is approaching closer than the first threshold.

With this configuration, when maintenance worker M approaches below counterweight 12, airbag 23 inflates downward from the lower end of counterweight 12. Therefore, even if maintenance worker M collides with the counterweight, the impact of the collision is mitigated by the airbag 23 acting as a shock absorber.

The airbag 23 also deploys diagonally downward and forward.

With this configuration, the airbag 23 deploys away from the inner wall 4 of the elevator shaft 3, pushing the maintenance worker M away to the side of the pit 7 where there is more space. This prevents the maintenance worker M from colliding with the weight frame 17 or other objects.

The counterweight 12 also includes a power generator 27 and a battery 28. The power generator 27 generates electricity through the rotation of a rotor attached to the counterweight 12. Here, the rotor rotates in conjunction with the movement of the counterweight 12. The rotor is, for example, a guide roller 22 that contacts the guide rail 16. The battery 28 stores the electricity generated by the power generator 27. The battery 28 supplies the stored electricity to the distance sensor 24 and the detection unit 30.

With this configuration, power is stored in the battery 28 during normal operation of the elevator 1. Because the distance sensor 24 and detection unit 30 can operate using the power stored in the battery 28, wiring for supplying power from an external source can be omitted. This prevents the structure of the counterweight 12 from becoming complicated. Furthermore, because the collision mitigation device 20 can operate independently of other equipment such as the control panel 14, it can operate more reliably even if an abnormality occurs in the control panel 14 or other equipment.

The counterweight 12 also includes a warning unit 31. The warning unit 31 outputs a warning signal to warn the maintenance worker M. The detection unit 30 detects that the maintenance worker M is approaching closer than the second threshold when the distance measured by the distance sensor 24 is shorter than the second threshold. The second threshold is a distance threshold that is preset to a distance longer than the first threshold. The warning unit 31 outputs a warning signal when the detection unit 30 detects that the maintenance worker M is approaching closer than the second threshold.

This configuration allows the maintenance technician M to be warned before the airbag 23 is deployed, preventing the airbag 23 from being deployed more than necessary. If the airbag 23 is deployed, recovery work will be required, but because the airbag 23 is not deployed more than necessary, the impact on the efficiency of maintenance work is reduced.

Furthermore, the warning unit 31 outputs a warning signal when the maintenance worker M approaches closer than the second threshold to the alarm device 26, which issues a warning sound when the warning signal is received.
Furthermore, the warning unit 31 outputs a warning signal when the maintenance worker M approaches closer than the second threshold to a lighting device that lights up or flashes when the warning signal is received.
The counterweight 12 also includes a jetting device 25. When the jetting device 25 receives a warning signal, it jets gas downward from a jetting port provided at the lower end of the counterweight 12. The warning unit 31 outputs a warning signal to the jetting device 25 when the maintenance worker M approaches closer than the second threshold.

When the warning is given by audio, it is possible to effectively warn maintenance personnel M who are not paying attention to the counterweight 12, etc. Furthermore, when the warning is given by lighting or flashing a lighting device, it is possible to effectively warn even in situations where noise is being generated. When the warning is given by gas being emitted from the gas ejection device 25, it is possible to warn maintenance personnel M using a sense other than hearing or sight. Furthermore, when these warning methods are used in combination, it is less likely that the warning will be overlooked or missed.

Note that the placement of parts of the impact mitigation device 20, such as the power generation device 27, battery 28, or control device 29, is not limited to the lower end of the counterweight 12. These devices may also be provided, for example, above the counterweight 12.

Next, an example of the hardware configuration of the collision mitigation device 20 will be described with reference to FIG.
FIG. 6 is a hardware configuration diagram of the main part of the collision mitigation device 20 according to the first embodiment.

Each function of the collision mitigation device 20 may be realized by a processing circuit. The processing circuit includes at least one processor 100a and at least one memory 100b. The processing circuit may include at least one dedicated hardware 200 in addition to or in place of the processor 100a and memory 100b.

When the processing circuit includes a processor 100a and memory 100b, each function of the collision mitigation device 20 is realized by software, firmware, or a combination of software and firmware. At least one of the software and firmware is written as a program. The program is stored in memory 100b. The processor 100a realizes each function of the collision mitigation device 20 by reading and executing the program stored in memory 100b.

The processor 100a is also called a CPU (Central Processing Unit), processing unit, arithmetic unit, microprocessor, microcomputer, or DSP. The memory 100b is composed of non-volatile or volatile semiconductor memory such as RAM, ROM, flash memory, EPROM, or EEPROM.

When the processing circuitry comprises dedicated hardware 200, the processing circuitry may be implemented, for example, as a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, an ASIC, an FPGA, or a combination thereof.

Each function of the collision mitigation device 20 can be realized by a processing circuit. Alternatively, all functions of the collision mitigation device 20 can be realized collectively by a processing circuit. Some of the functions of the collision mitigation device 20 may be realized by dedicated hardware 200, and other parts may be realized by software or firmware. In this way, the processing circuit realizes each function of the collision mitigation device 20 by dedicated hardware 200, software, firmware, or a combination of these.

Figure 7 is a front view of the counterweight 12 according to a first variant of embodiment 1.

The counterweight 12 is equipped with a counterweight sheave 32. The counterweight sheave 32 is attached to the upper edge of the counterweight frame 17. The main rope 10 on the counterweight 12 side is wound around the counterweight sheave 32. In this case, when the counterweight 12 travels up and down due to the winding or unwinding of the main rope 10, the counterweight sheave 32 rotates. At this time, the power generator 27 of the collision mitigation device 20 may generate electricity by the rotation of the counterweight sheave 32.

Figure 8 is a side view of the counterweight 12 according to a second variant of embodiment 1.

In this example, the bottom surface of the weight frame 17 of the counterweight 12 is tilted forward. At this time, the discharge port of the airbag 23 in the collision mitigation device 20 is directed downward and diagonally forward. This makes it easier for the airbag 23 to deploy downward and diagonally forward. In other words, the collision mitigation device 20 makes it easier for the airbag 23 to push the maintenance worker M away from the inner wall 4 of the elevator shaft 3 and allow him to escape.

Embodiment 2.
In the second embodiment, differences from the example disclosed in the first embodiment will be described in particular detail. For features not described in the second embodiment, any of the features of the example disclosed in the first embodiment may be adopted.

FIG. 9 is a diagram showing an example of deployment of the airbag 23 according to the second embodiment.
In FIG. 9, the counterweight 12 is shown viewed from the side.

Figure 9 shows the shape of the airbag 23 immediately after deployment. Here, the shape immediately after deployment refers to the shape of the airbag 23 at its most inflated point immediately after deployment is complete. The airbag 23 may deflate from the shape illustrated in Figure 9 after deployment. The airbag 23 is shaped so that the lower end on the rear side is lower than the lower end on the front side. That is, the airbag 23 is shaped so that the lower end is biased toward the rear side. The lower end on the rear side of the airbag 23 is, for example, the lower end of the part of the airbag 23 that is rearward of the center of gravity or center of the inflated part. In this case, the lower end on the front side of the airbag 23 is, for example, the lower end of the part of the airbag 23 that is frontward of the center of gravity or center of the inflated part. Due to this shape of the airbag 23, the rear side of the airbag 23 deploys before the front side. That is, the speed at which the airbag 23 inflates downward is greater on the rear side than on the front side.

As described above, in the impact mitigation device 20 for the counterweight 12 according to the second embodiment, the airbag 23 is deployed so that the rear side precedes the front side.
In addition, immediately after deployment, the airbag 23 has a shape in which the lower end on the rear side is lower than the lower end on the front side.

This configuration makes it easier for maintenance personnel M to be pushed away to the side of the pit 7 where there is more space. This more effectively prevents maintenance personnel M from colliding with the weight frame 17 and other objects.

The airbag 23 may have a shape as shown in Figure 9 during deployment. For example, the airbag 23 may have a shape during deployment in which the lower end on the rear side is lower than the lower end on the front side. In this case, the airbag 23 may inflate to a shape in which the lower end on the rear side is lower than the lower end on the front side, and then the front side may inflate further.

To summarize the above explanation, possible configurations of the technology according to the present disclosure include the configurations listed below as appendices.
(Appendix 1)
a counterweight that is disposed in the hoistway such that its back surface faces the inner wall of the hoistway, and that travels in the hoistway while being guided by a guide rail whose longitudinal direction is the up-down direction,
a distance sensor that measures the distance from the lower end of the counterweight to a maintenance worker located below;
a detection unit that detects that the maintenance worker is approaching closer than a first threshold when the distance measured by the distance sensor is shorter than a predetermined first threshold;
an airbag that is disposed at a lower end of the counterweight and that deploys downward when the detection unit detects that the maintenance worker is approaching closer than the first threshold;
A counterweight comprising:
(Appendix 2)
The airbag deploys so that the rear side precedes the front side.
2. The counterweight of claim 1.
(Appendix 3)
The airbag has a shape immediately after deployment in which the lower end portion on the rear side is lower than the lower end portion on the front side.
2. The counterweight of claim 1.
(Appendix 4)
The airbag deploys downward and diagonally forward.
2. The counterweight of claim 1.
(Appendix 5)
a power generating device that generates electricity by the rotation of a rotor that rotates in conjunction with the movement of the counterweight and is provided on the counterweight;
a battery that stores the power generated by the power generation device and supplies the stored power to the distance sensor and the detection unit;
5. The counterweight of any one of claims 1 to 4, comprising:
(Appendix 6)
The rotating body is a guide roller that contacts the guide rail.
6. The counterweight of claim 5.
(Appendix 7)
The rotating body is a counterweight sheave around which a main rope supporting the load of the counterweight is wound.
6. The counterweight of claim 5.
(Appendix 8)
a warning unit that outputs a warning signal to warn the maintenance person,
the detection unit detects that the maintenance worker is approaching closer than the second threshold when the distance measured by the distance sensor is shorter than a second threshold that is preset to be longer than the first threshold,
The warning unit outputs the warning signal when the detection unit detects that the maintenance worker is approaching closer than the second threshold.
8. The counterweight of any one of claims 1 to 7.
(Appendix 9)
The warning unit outputs the warning signal to an alarm device that issues a warning sound when the warning signal is received.
9. The counterweight of claim 8.
(Appendix 10)
The warning unit outputs the warning signal to a lighting device that lights up or flashes when the warning signal is received.
9. The counterweight of claim 8.
(Appendix 11)
a jetting device that jets gas downward from a jetting port provided at a lower end of the counterweight when the warning signal is received,
The warning unit outputs the warning signal to the ejection device.
9. The counterweight of claim 8.
(Appendix 12)
The counterweight is attached to the lower end of a counterweight that travels while being guided by a guide rail with its longitudinal direction in the up-down direction in the hoistway that is arranged so that its back surface faces the inner wall of the hoistway,
a distance sensor that measures the distance from the lower end of the counterweight to a maintenance worker located below the counterweight;
a detection unit that detects that the maintenance worker is approaching closer than a first threshold when the distance measured by the distance sensor is shorter than a predetermined first threshold;
an airbag that deploys downward when the detection unit detects that the maintenance worker is approaching closer than the first threshold;
A collision mitigation device comprising:

1. Elevator, 2. Building, 3. Hoistway, 4. Interior wall, 5. Landing, 6. Landing door, 7. Pit, 8. Pit light, 9. Hoisting machine, 10. Main rope, 11. Cage, 12. Counterweight, 13. Buffer, 14. Control panel, 15. Cage door, 16. Guide rail, 17. Counterweight frame, 18. Counterweight block, 19. Counterweight guide, 20. Collision mitigation device, 21. Spacer, 22. Guide roller, 23. Airbag, 24. Distance sensor, 25. Ejector, 26. Alarm device, 27. Power generator, 28. Battery, 29. Control device, 30. Detection unit, 31. Warning unit, 32. Counterweight sheave, 100a. Processor, 100b. Memory, 200. Dedicated hardware

Claims (12)

a counterweight that is disposed in the hoistway such that its back surface faces the inner wall of the hoistway, and that travels in the hoistway while being guided by a guide rail whose longitudinal direction is the up-down direction,
a distance sensor that measures the distance from the lower end of the counterweight to a maintenance worker located below;
a detection unit that detects that the maintenance worker is approaching closer than a first threshold when the distance measured by the distance sensor is shorter than a predetermined first threshold;
an airbag that is disposed at a lower end of the counterweight and that deploys downward when the detection unit detects that the maintenance worker is approaching closer than the first threshold;
A counterweight comprising: The airbag deploys so that the rear side precedes the front side.
2. The counterweight of claim 1. The airbag has a shape immediately after deployment in which the lower end portion on the rear side is lower than the lower end portion on the front side.
2. The counterweight of claim 1. The airbag deploys downward and diagonally forward.
2. The counterweight of claim 1. a power generating device that generates electricity by the rotation of a rotor that rotates in conjunction with the movement of the counterweight and is provided on the counterweight;
a battery that stores the power generated by the power generation device and supplies the stored power to the distance sensor and the detection unit;
5. A counterweight according to claim 1, comprising: The rotating body is a guide roller that contacts the guide rail.
6. A counterweight according to claim 5. The rotating body is a counterweight sheave around which a main rope supporting the load of the counterweight is wound.
6. A counterweight according to claim 5. a warning unit that outputs a warning signal to warn the maintenance person,
the detection unit detects that the maintenance worker is approaching closer than the second threshold when the distance measured by the distance sensor is shorter than a second threshold that is preset to be longer than the first threshold,
The warning unit outputs the warning signal when the detection unit detects that the maintenance worker is approaching closer than the second threshold.
A counterweight according to any one of claims 1 to 4. The warning unit outputs the warning signal to an alarm device that issues a warning sound when the warning signal is received.
9. A counterweight according to claim 8. The warning unit outputs the warning signal to a lighting device that lights up or flashes when the warning signal is received.
9. A counterweight according to claim 8. a jetting device that jets gas downward from a jetting port provided at a lower end of the counterweight when the warning signal is received,
The warning unit outputs the warning signal to the ejection device.
9. A counterweight according to claim 8. The elevator is attached to a lower end of a counterweight that travels while being guided by a guide rail with its longitudinal direction in the up-down direction in the elevator shaft that is arranged so that its back surface faces the inner wall of the elevator shaft,
a distance sensor that measures the distance from the lower end of the counterweight to a maintenance worker located below the counterweight;
a detection unit that detects that the maintenance worker is approaching closer than a first threshold when the distance measured by the distance sensor is shorter than a predetermined first threshold;
an airbag that deploys downward when the detection unit detects that the maintenance worker is approaching closer than the first threshold;
A collision mitigation device comprising: