WO2024121925A1

WO2024121925A1 - Terminal floor forced deceleration device for elevator

Info

Publication number: WO2024121925A1
Application number: PCT/JP2022/044863
Authority: WO
Inventors: 勇来齊藤; 亮前田; 尚史保立
Original assignee: 株式会社日立製作所
Priority date: 2022-12-06
Filing date: 2022-12-06
Publication date: 2024-06-13

Abstract

Disclosed is a terminal floor forced deceleration device for an elevator with which the speed of the impact of a car with a buffer can be reduced even while braking the car by means of a mechanical brake during an emergency stop. The terminal floor forced deceleration device is configured so that, if the speed of a car (1) of an elevator provided with a buffer (300) at a bottom part of a shaft exceeds a prescribed excessive speed threshold that is set according to the position of the car, the supply of power to a hoisting machine (4) is cut and a brake device is operated to decelerate the car. The terminal floor forced deceleration device comprises: an emergency stop device (200) that is provided to the car; an electric operation apparatus (10) that is provided to the car, and that operates the emergency stop device; and a safety control device (100) that operates the electric operation apparatus. The safety control device operates the electric operation apparatus according to the deceleration of the car.

Description

Elevator terminal floor deceleration device

The present invention relates to a forced deceleration device for elevator terminal floors that uses a braking device to decelerate the elevator car in an emergency.

As a safety device, a buffer that corresponds to the rated speed of the elevator is installed at the bottom of the elevator shaft. As the rated speed increases, the length of the buffer increases, which means the depth of the shaft pit also increases.

The length of the buffer can be reduced by suppressing the speed at which the car collides with the buffer during an emergency stop. The collision speed of such a car is suppressed by forcibly stopping the car using a terminal floor forced deceleration device when an abnormality occurs in the car's deceleration control at the lowest floor, i.e., the terminal floor.

The technology described in Patent Document 1 is known as a conventional technology related to a terminal floor forced deceleration device.

This elevator system according to the conventional technology includes a means for setting a first set speed that varies depending on the position of the car in the elevator shaft, a means for setting a second set speed that is faster than the first set speed and varies depending on the position of the car in the elevator shaft, a mechanical brake that operates when the elevator car speed exceeds the first set speed, and an emergency stop device that operates when the elevator car speed exceeds the second set speed.

If an abnormality occurs while the car is descending, causing the car to overspeed and exceed the first set speed near the lowest floor, a mechanical brake is activated. This brakes the car, thereby reducing the speed at which the car strikes the buffer.

International Publication No. 2004/031064

In the above conventional technology, the magnitude of the collision speed depends on the braking force of the mechanical brake, so when considering fluctuations in braking force due to aging, etc., the collision speed that the buffer must respond to becomes large.

The present invention provides a forced deceleration device for elevator terminal floors that can reduce the collision speed of the car against the buffer while braking the car with a mechanical brake during an emergency stop.

In order to solve the above problems, the elevator terminal floor forced deceleration device of the present invention cuts off the power supply to the hoist and activates the brake device to decelerate the car when the speed of the car of an elevator with a buffer installed at the bottom of the hoistway exceeds a predetermined overspeed threshold set according to the position of the car. The device comprises an emergency stop device installed in the car, an electric actuator installed in the car for operating the emergency stop device, and a safety control device for operating the electric actuator, and the safety control device activates the electric actuator according to the deceleration of the car.

According to the present invention, the collision speed of the car with the buffer can be reduced while still braking the car with a mechanical brake during an emergency stop.

　Problems, configurations and advantages other than those mentioned above will become clear from the description of the embodiments below.

1 is a diagram showing the overall configuration of an elevator according to an embodiment of the present invention; 1 is a front view showing a mechanism section housed in a housing of an electric actuator in an embodiment, the electric actuator being in a standby state. 1 is a front view showing a mechanism section housed in a housing of an electric actuator in an embodiment, the electric actuator being in an operating state. FIG. 2 is a functional block diagram showing a configuration of a safety controller in the embodiment. 4 is a flowchart showing a processing operation of a safety controller in the embodiment. 1 is a graph illustrating an example of a relationship between car speed and position in an embodiment.

The following describes an embodiment of the present invention with reference to the following examples and drawings.

In each figure, the same reference numbers indicate the same components or components with similar functions.

FIG. 1 is a diagram showing the overall configuration of an elevator according to an embodiment of the present invention.

As shown in FIG. 1, in the embodiment, a car 1 and a counterweight 2 are mechanically connected to one end and the other end of a main rope 3, respectively. The main rope 3 is wound around a sheave provided on a hoist 4. This allows the car 1 and the counterweight 2 to be suspended in a hoistway provided in a building. In other words, the embodiment is a so-called bucket-type elevator. In the embodiment, the hoist 4 is installed in a machine room provided above the hoistway. In addition, a buffer 300 is provided at the bottom of the hoistway as a safety device.

When the motor of the hoist 4 rotates and the sheave is rotated, the main rope 3 is driven linearly by the frictional force between the sheave and the main rope 3. As a result, the car 1 and the counterweight 2 move up and down in opposite directions to each other within the hoistway.

The car 1 is movably engaged with the guide rail 5 via a guide device (e.g., a guide shoe) not shown. Therefore, the car 1 moves between the lowest floor FL1 and any of the other floors (FL2, etc.) while being guided by the guide rail 5. In the embodiment, a general T-shaped guide rail is used as the guide rail 5. The counterweight 2 moves while being guided by a guide rail for the counterweight not shown.

Normal operation of the car 1 is controlled by an elevator control device 6 that is installed in the machine room together with the hoist 4. The hoist 4 is equipped with an AC motor such as a synchronous motor. This AC motor is driven and controlled by an inverter device equipped in the elevator control device 6, thereby controlling the speed and position of the car 1. The elevator control device 6 controls the operation of the car 1 based on a detection signal from a rotation detector (e.g., a rotary encoder) (not shown) that detects the rotation of the hoist 4, and a detection signal from a position detection device that detects the position of the car 1 in the elevator shaft.

The position detection device is composed of, for example, a shielding plate fixed inside the elevator shaft and a photoelectric sensor provided in the car 1.

The hoist 4 is equipped with an electromagnetic brake device (not shown) as a brake device. The elevator control device 6 controls the car 1 to decelerate toward the stop floor, and when the car 1 reaches the stop floor, the elevator control device 6 transitions the electromagnetic brake device from an open state to a braked state. This keeps the car 1 stopped.

A safety control device (100) (hereinafter, referred to as "safety controller 100") is installed on the top of the car 1. The safety controller 100 has the function of controlling the emergency stop device 200 provided on the car 1 and the electromagnetic brake device provided on the hoist 4 to bring the car 1 to an emergency stop or forcibly decelerate the car 1 near the lowest floor FL1, i.e., the terminal floor.

The safety controller 100 is electrically connected to a position sensor 50 installed on the top of the car 1. In the embodiment, the position sensor 50 is composed of an image sensor (e.g., a CCD or CMOS sensor). The position sensor 50 acquires a surface image of the guide rail 5, which is a stationary object in the elevator shaft. In the embodiment, a surface image of the tip of the T-shaped foot is acquired as the surface image of the guide rail 5. The safety controller 100 measures the position and speed of the car 1 based on the surface image of the guide rail 5 acquired by the image sensor 9.

The safety controller 100 and the elevator control device 6 are electrically connected by a tail cord 7 so as to be able to communicate with each other and to be able to supply power to the safety controller 100 .

When the safety controller 100 determines that the car 1 is overspeeding based on the detection signal from the position sensor 50, it activates the electromagnetic brake device or emergency stop device 200 provided on the hoist 4 to bring the car 1 to an emergency stop.

The safety controller 100 operates the electric actuator 10 to pull up the lifting rod 21, thereby operating the emergency stop device 200. In the embodiment, the emergency stop device 200 is a known emergency stop device having a wedge-shaped brake.

In this embodiment, the electric actuator 10 is an electromagnetic actuator, and is disposed on the top of the car 1. The electromagnetic actuator has a movable piece or movable rod that is operated by, for example, a solenoid or an electromagnet. The electric actuator 10 operates when the position sensor 50 detects a predetermined overspeed state of the car 1. At this time, the lifting rod 21 is lifted by the drive mechanism (12, 16, 17, 18, etc.) connected to the operating lever 11. This causes the emergency stop device 200 to enter a braking state.

The emergency stop devices 200 are arranged on the left and right sides of the car 1. Each emergency stop device 200 is equipped with a pair of brakes (not shown), which are movable between a braking position and a non-braking position, and clamp the guide rail 5 in the braking position. Furthermore, when the brakes rise relatively due to the descent of the car 1, a braking force is generated by the frictional force acting between the brakes and the guide rail 5. As a result, the emergency stop devices 200 are activated when the car 1 falls into an overspeeding state, and bring the car 1 to an emergency stop.

The elevator of the embodiment is equipped with a so-called ropeless governor system that does not use a governor rope, and when the ascent/descent speed of the car 1 exceeds the rated speed and reaches a first overspeed (e.g., a speed not exceeding 1.3 times the rated speed), the power supply of the hoisting machine 4 and the power supply of the elevator control device 6 that controls this drive device are cut off. Also, when the descent speed of the car 1 reaches a second overspeed (e.g., a speed not exceeding 1.4 times the rated speed), the electric operator 10 provided on the car 1 is electrically driven, and the emergency stop device 200 is operated to bring the car 1 to an emergency stop.

In the embodiment, the ropeless governor system is composed of the aforementioned position sensor 50 and a safety controller 100 that determines the overspeed state of the car 1 based on the detection signal of the position sensor 50. This safety controller 100 measures the speed of the car 1 based on the output signal of the position sensor 50, and when it determines that the measured speed has reached a first overspeed, it outputs a command signal to cut off the power supply of the hoist 4 and the power supply of the elevator control device 6 that controls the hoist 4. In addition, when the safety controller 100 determines that the measured speed has reached a second overspeed, it outputs a command signal to operate the electric actuator 10.

When the pair of brakes provided on the emergency stop device 200 are pulled up by the lifting rod 21, the pair of brakes clamp the guide rail 5. The lifting rod 21 is driven by the electric actuator 10.

The configuration and operation of the electric actuator 10 will be explained below. Note that the explanation will be given with reference to FIG. 1, but for details not shown in FIG. 1, refer to FIG. 2 as appropriate.

As shown in FIG. 1, the operating lever 11 and the first operating piece 16 are connected to form a roughly T-shaped first link member. The operating lever 11 and the first operating piece 16 form the head and foot of the T, respectively. The roughly T-shaped first link member is rotatably supported by a crosshead (not shown) at the connection between the operating lever 11 and the first operating piece 16. One end of a pair of lifting rods 21 (on the left side in the figure) is connected to the end of the first operating piece 16, which forms the foot of the T, on the opposite side to the connection between the operating lever 11 and the first operating piece 16.

The connecting piece 17 and the second operating piece 18 are connected to form a second link member that is approximately T-shaped. The connecting piece 17 and the second operating piece 18 form the head and foot of the T, respectively. The approximately T-shaped second link member is rotatably supported by a crosshead (not shown) at the connection between the connecting piece 17 and the second operating piece 18. The other end (left side in the figure) of the pair of lifting rods 21 is connected to the end of the second operating piece 18, which forms the foot of the T, on the opposite side to the connection between the connecting piece 17 and the second operating piece 18.

The end of the operating lever 11 extending from the inside to the outside of the housing (reference number 30 in FIG. 2) and the end of the connecting piece 17 that is closest to the top of the car 1 are connected to one end (left side in FIG. 2) and the other end (right side in FIG. 2) of the drive shaft 12 lying on the car 1. The drive shaft 12 slidably passes through a fixed part (reference number 14 in FIG. 2) that is fixed to the crosshead. The drive shaft 12 also passes through a pressing member (reference number 15 in FIG. 2), which is fixed to the drive shaft 12. The pressing member 15 (FIG. 2) is located on the second link member (connecting piece 17, second operating piece 18) side of the fixed part. Between the fixed part 14 (FIG. 2) and the pressing member 15 (FIG. 2), a driving spring (reference number 13 in FIG. 2) that is an elastic body is located, and the drive shaft 12 is inserted into the drive spring 13 (FIG. 2).

When the electric actuator 10 is operated, that is, in this embodiment, when the power supply to the electromagnet is cut off, the electromagnetic force that constrains the movement of the operating lever 11 against the biasing force of the drive spring 13 (Fig. 2) disappears, and the drive shaft 12 is driven along the longitudinal direction by the biasing force of the drive spring 13 (Fig. 2) applied to the pressing member 15 (Fig. 2). As a result, the first link member (operating lever 11, first operating piece 16) rotates, and the second link member (connecting piece 17, second operating piece 18) rotates. As a result, one of the lifting rods 21 connected to the first operating piece 16 of the first link member is driven and pulled up, and the other lifting rod 21 connected to the second operating piece 18 of the second link member is driven and pulled up.

FIG. 2 shows the mechanism stored in the housing 30 of the electric actuator 10 in the embodiment, and is a front view in the installed state of FIG. 1. In FIG. 2, the emergency stop device 200 (FIG. 1) is in an inoperative state, and the electric actuator 10 is in a standby state. In other words, the elevator is in a normal operating state.

As shown in FIG. 2, in the standby state, the armature 34 connected to the operating lever 11 is attracted to the excited electromagnet 35. This restricts the movement of the operating lever 11 against the biasing force of the drive spring 13 (compression spring). The operating lever 11 is connected to the armature 34 via a bracket 38 that is rotatably mounted on the armature 34. At least the portion of the armature 34 that is attracted to the electromagnet 35 is made of a magnetic material.

The other mechanisms (36, 37, 40-42) in Figure 2 will be described later (Figure 3).

In this embodiment, a flexible cover member 32 is provided on the housing cover 31, which is the top surface of the housing 30, at an opening through which the operating lever 11 passes, to cover this opening. For example, the cover member 32 is made of a thin rubber material. Because the cover member 32 is flexible, the movement of the operating lever 11 is not impeded when the emergency stop device is activated.

The cover member 32 prevents dust and foreign objects from entering the housing 30 and adhering to or coming into contact with the mechanism. This improves the reliability of the operation of the electric actuator in the installation environment (such as inside the elevator shaft). This improves the reliability of the operation of the emergency stop device.

In the embodiment, a plate-like member 33 is further provided on the operating lever 11. The plate-like member 33 is fixed to the connection between the bracket 38 and the operating lever 11. The flat surface of the plate-like member 33 is located within the housing 30, directly below the opening in the housing cover 31 through which the operating lever 11 passes and in the space around it, and covers the mechanism located directly below the opening. This prevents dust, foreign matter, etc. from adhering to or coming into contact with the mechanism even if dust, foreign matter, etc. enters the housing 30. This more reliably improves the reliability of the operation of the electric operating device in the installation environment (such as in a hoistway). This more reliably improves the reliability of the operation of the emergency stop device.

FIG. 3 shows the mechanism stored in the housing 30 of the electric actuator 10 in the embodiment, and is a front view in the installed state of FIG. 1. In FIG. 3, the emergency stop device 200 (FIG. 1) is in a braking state, and the electric actuator 10 is in an operating state. In other words, the elevator system is stopped by the emergency stop device 200.

When the excitation of the electromagnet 35 is stopped by a command signal from the safety controller 100, the attractive force acting on the armature 34 disappears, and the biasing force of the drive spring 13 is released to drive the drive shaft 12. When the drive shaft 12 is driven, the operating lever 11 connected to the drive shaft 12 rotates around the first operating shaft 19, and in conjunction with this, the first operating piece 16 connected to the operating lever 11 rotates around the first operating shaft 19. As a result, the lifting rod 21 connected to the first operating piece is lifted.

When the operating lever 11 rotates as described above, the armature 34 connected to the operating lever 11 moves in the direction of rotation of the operating lever 11. To return the electric operating device 10 to the standby state shown in FIG. 2, the armature 34 is returned from the moving position (FIG. 3) to the standby position (FIG. 2) by a mechanism (36, 37, 40-42) not described in FIG. 2, as described below.

As shown in FIG. 3, the electric actuator 10 has a feed screw 36 located on the flat surface of the substrate 40 to drive the armature 34. The feed screw is rotatably supported by a first support member 41 and a second support member 42 fixed on the flat surface of the substrate 40. The electromagnet 35 has a nut portion, which screws into the feed screw 36. The feed screw 36 is rotated by a motor 37.

To return the electric actuator 10 to the standby state, first, while exciting the electromagnet 35, the motor 37 is driven to rotate the feed screw. The rotating feed screw and the nut portion of the electromagnet 35 convert the rotation of the motor into linear movement of the electromagnet 35 along the axial direction of the feed screw. As a result, the electromagnet 35 approaches the movement position of the armature 34 shown in FIG. 3, and the armature 34 is attracted to the electromagnet 35 due to the electromagnetic force of the electromagnet 35. Once the armature 34 is attracted to the electromagnet 35, the direction of rotation of the motor 37 is reversed while continuing to excite the electromagnet 35, and the feed screw is reversed. As a result, the armature 34 moves to the standby position together with the electromagnet 35.

In the embodiment, the plate-like member 33 is fixed to the operating lever 11 within the space inside the housing 30, and therefore moves together with the operating lever 11. In other words, the plate-like member 33 does not interfere with the movement of the operating lever 11.

In the embodiment, in order to fix the plate-like member 33 to the operating lever 11, the plate-like member 33 and the operating lever 11 are fitted together without any gaps or are tightly connected with an adhesive or bonding material. Therefore, the plate-like member 33 and the operating lever 11 are connected to each other without any gaps at their connection points. Therefore, the plate-like member 33 reliably prevents dust, foreign matter, etc. from adhering to or coming into contact with the mechanism.

Next, we will explain the terminal floor forced deceleration device equipped in the elevator of the embodiment.

In this embodiment, the terminal floor forced deceleration device is composed of an electromagnetic brake device and a safety controller 100 provided on the hoisting machine 4, and further includes an electric actuator 10 controlled by the safety controller 100, and an emergency stop device 200 operated by the electric actuator 10.

FIG. 4 is a functional block diagram showing the configuration of the safety controller 100 in the embodiment. Note that FIG. 4 shows the functions of the safety controller 100 related to forced deceleration at the final floor and emergency stop.

In the embodiment, the safety controller 100 is composed of a computer system such as a microcomputer. The computer system executes a predetermined program to function as each part.

As shown in FIG. 4, the safety controller 100 includes a position detection unit 101, an overspeed threshold calculation unit 102, a first overspeed determination unit 103, a power cutoff unit 104, a speed detection unit 105, a second overspeed determination unit 106, an electric actuator operation unit 107, a deceleration calculation unit 108, and a deceleration determination unit 109.

The position detection unit 101 detects the position of the car 1 in the height direction of the elevator shaft based on the detection signal output by the position sensor 50 for detecting the position of the car 1.

In this embodiment, an image sensor is used as the position sensor 50.

The position detection unit 101 detects the position of the car 1 by image processing the image of the exposed surface of the guide rail 5 acquired by the image sensor. For example, the position detection unit 101 calculates the image shift Δd at two points in time (time t and time t+Δt: Δt is, for example, a frame period) by an image correlation method. The position detection unit 101 calculates the travel distance d of the car 1 by sequentially accumulating Δd calculated for each Δt, and further calculates the position of the car 1 based on the travel distance d.

The overspeed threshold calculation unit 102 calculates the overspeed threshold, which is the reference speed of the car when the car 1 is brought to an emergency stop while in motion by stopping the hoist 4, according to the position of the car 1 detected by the position detection unit 101.

The overspeed threshold calculation unit 102 calculates the overspeed threshold by using a formula or table data that indicates the relationship between the position of the car 1 and the overspeed threshold. For example, the overspeed threshold _Vth is calculated by the formula "Vth = (2a0·L + Vc2)1/2" using the distance L from the position of the car 1 to the upper surface of the buffer 300, the magnitude of deceleration _a0 (>0: standard value) caused by an electromagnetic brake device ( _not shown) provided in the hoist 4, and the collision speed _Vc (allowable value) of the _car ₁ with ^{the buffer 300} ^.

The overspeed threshold _Vth varies depending on the position of the car 1, but the value calculated by the formula increases as the car moves away from the lowest floor. Therefore, when the calculated value is equal to or greater than the above-mentioned first overspeed, the overspeed threshold calculation unit 102 sets the overspeed threshold to the first overspeed. When the calculated value is smaller than the first overspeed, the overspeed threshold calculation unit 102 sets the overspeed threshold to the calculated value.

The first overspeed determination unit 103 determines whether the speed of the car 1 detected by the speed detection unit 105 described below is greater than the overspeed threshold set by the overspeed threshold calculation unit.

When the power cutoff unit 104 receives a determination result from the first overspeed determination unit 103 that the speed of the car 1 is greater than the overspeed threshold, it sends a signal commanding the cutting off of the power supply from the power source to the hoist 4. This stops the drive of the hoist 4, and the electromagnetic brake device equipped in the hoist 4 transitions from an open state to a braking state. Therefore, the car 1 comes to an emergency stop.

In the embodiment, the AC motor provided in the hoisting machine 4 is driven at a variable speed by AC power from the inverter device. The inverter device is connected to the power source for the drive via an electromagnetic contactor. The inverter device converts the power from the power source for the drive into AC power for driving the AC motor. When the contacts of the electromagnetic contactor are opened by a signal from the power source cutoff unit 104, the power supply from the power source for the drive to the inverter device is cut off.

The speed detection unit 105 detects the speed of the car 1 based on the detection signal output by the position sensor 50.

The speed detection unit 105 detects the speed of the car 1 by image processing the image of the exposed surface of the guide rail 5 acquired by the position sensor 50, i.e., the image sensor. For example, the position detection unit 101, like the position detection unit, calculates the image shift Δd at two points in time (time t and time t+Δt: Δt is, for example, a frame period) by image correlation. Furthermore, the speed detection unit 105 calculates the speed of the car 1 (= Δd/Δt) using the calculated image shift Δd.

The second overspeed determination unit 106 determines whether the speed of the car 1 detected by the speed detection unit 105 is greater than a preset emergency stop activation threshold. The emergency stop activation threshold is equal to the second overspeed value described above.

When the electric actuator operating unit 107 receives a judgment result from the second overspeed judgment unit 106 that the speed of the car 1 is greater than the emergency stop operation threshold, it sends a signal commanding the operation of the electric actuator 10. This causes the electric actuator 10 to operate, and the emergency stop device 200 to operate. Therefore, the car 1 comes to an emergency stop.

In addition, the electric actuator actuation unit 107 also sends a signal to command the operation of the electric actuator 10 when it receives a judgment result from the deceleration judgment unit 109 described below.

The deceleration calculation unit 108 calculates the deceleration of the car 1 based on the speed (v) of the car 1 detected by the speed detection unit 105.

If the image shift between times _t0 and _t1 (= _t0 +Δt) is _Δd1 , and the image shift between times _t1 and _t2 (= _t1 +Δt) is _Δd2 , the speed of car 1 detected by the speed detection unit 105 is _Δd1 /Δt (= _v1 ) at time _t1 , and _Δd2 /Δt (= _v2 ) at time t2. The deceleration calculation unit 108 calculates the deceleration a (=( _v2 _-v1 )/Δt=( _Δd2 _-Δd1 )/(Δt) ² ) based on _v1 and _v2 . The calculated value of a is negative if car 1 is decelerating, and positive if car 1 is accelerating.

The deceleration determination unit 109 determines whether the deceleration calculated by the deceleration calculation unit 108 is smaller than a preset threshold value. The deceleration determination unit 109 first determines whether the deceleration a calculated by the deceleration calculation unit 108 is negative, i.e., determines whether the car 1 is decelerating, and if it is decelerating, determines whether the magnitude (|a| or −a) of a (<0) is smaller than a threshold value a _th (>0).

In this embodiment, the threshold value a _th is set to the magnitude of the deceleration before the braking force of the electromagnetic brake device fluctuates due to aging or the like, that is, the standard value (a ₀ described above).

When the electric operator actuation unit 107 receives a determination result from the deceleration determination unit 109 that the magnitude of the deceleration of the car 1 is smaller than the threshold value a _th , it sends out a signal to command the operation of the electric operator 10. This causes the electric operator 10 to operate, and the safety device 200 to operate, thereby suppressing the collision speed of the car 1 with the buffer 300.

According to the embodiment, if the braking force of the electromagnetic brake device fluctuates due to aging or the like, the collision speed of the car 1 with the buffer 300 is suppressed by the emergency stop device 200. As a result, the buffer 300 only needs to be able to handle the collision speed when a standard deceleration is obtained, without having to provide a margin to account for fluctuations in the braking force.

FIG. 5 is a flowchart showing the processing operation of the safety controller 100 in the embodiment. The following explanation will be given with reference to FIG. 4 as appropriate.

When the safety controller 100 starts processing, in step S1 it determines whether the car 1 is descending.

The image acquired by the position sensor 50 is shifted downward and upward in the image frame in accordance with the ascent and descent of the car 1, respectively. Therefore, by setting the above-mentioned image shift Δd to positive or negative depending on the direction of image shift, it is possible to determine whether the car 1 is ascending or descending depending on the positive or negative value of the speed detected by the speed detection unit 105. In the embodiment, the safety controller 100 determines whether the car 1 is descending using the second overspeed determination unit 106 that receives the speed detected by the speed detection unit 105 from the speed detection unit 105.

If the safety controller 100 determines that the car is not descending (NO in step S1), it executes step S1 again. If the safety controller 100 determines that the car is descending (YES in step S1), it then executes step S2.

In step S2, the safety controller 100 uses the second overspeed determination unit 106 to determine whether the speed of the car 1 detected by the speed detection unit 105 is greater than the emergency stop activation threshold (= second overspeed). If the safety controller 100 determines that the speed of the car 1 is greater than the emergency stop activation threshold (YES in step S2), it then executes step S7. If the safety controller 100 determines that the speed of the car 1 is not greater than the emergency stop activation threshold (NO in step S2), it then executes step S3.

In step S3, the safety controller 100 uses the first overspeed determination unit 103 to determine whether the speed of the car 1 detected by the speed detection unit 105 is greater than the overspeed threshold (the above-mentioned V _th ) calculated by the overspeed threshold calculation unit 102. If the safety controller 100 determines that the speed of the car 1 is greater than the overspeed threshold (YES in step S3), it then executes step S4. If the safety controller 100 determines that the speed of the car 1 is not greater than the overspeed threshold (NO in step S3), it executes step S1 again.

In step S4, the safety controller 100 uses the power cutoff unit 104 to cut off the power supply from the drive power source to the hoist 4. After executing step S4, the safety controller 100 then executes step S5.

In step S5, the safety controller 100 uses the deceleration calculation unit 108 to calculate the deceleration of the car 1 (above-mentioned a) based on the speed of the car 1 detected by the speed detection unit 105. After executing step S5, the safety controller then executes step S6.

In step S6, the safety controller 100 uses the deceleration determination unit 109 to determine whether the magnitude of the deceleration of the car 1 calculated in step S5 is smaller than a predetermined threshold value (the above-mentioned a _th ). If the safety controller 100 determines that the magnitude of the deceleration is smaller than the threshold value (YES in step S6), it then executes step S7. If the safety controller 100 determines that the magnitude of the deceleration is not smaller than the threshold value (NO in step S6), it executes step S6 again.

In step S7, the safety controller 100 operates the electric operator 10 by sending a signal commanding operation of the electric operator 10 using the electric operator operating unit 107. As a result, when the safety controller 100 executes step S7 after step S2, the emergency stop device 200 is activated and the car 1 is brought to an emergency stop. Also, when the safety controller 100 executes step S7 after step S6, the emergency stop device 200 is activated and the car 1 is braked, thereby suppressing the collision speed of the car 1 with the buffer 3001).

Once the safety controller executes step S7, it ends the series of processes.

FIG. 6 is a graph showing an example of the relationship between the speed and position of car 1 in the embodiment. In FIG. 6, the speed and position of car 1 are denoted as "car speed" and "car position", respectively.

Note that Figure 6 shows the stopping operation of car 1 at the terminal floor, i.e., the lowest floor.

When the car 1 is running normally, the electric motor of the hoist 4 is controlled to decelerate, causing the car 1 to decelerate towards the lowest floor and stop at the lowest floor.

If an abnormality occurs, the car 1 will travel without slowing down. Therefore, if the car speed exceeds the overspeed threshold Vth, the safety controller 100 will cut off the power supply to the hoist 4 (see "power cutoff unit 104" in Figure 4 and step S4 in Figure 5).

When the magnitude of the deceleration of the car 1 is maintained at the standard value (a ₀ described above), the car 1 reaches the upper surface of the buffer at a speed equal to or lower than the allowable collision speed of the buffer.

If the magnitude of the deceleration of the car 1 becomes smaller than the threshold value (a _th (=a ₀ ) described above) due to fluctuations in the braking force of the electromagnetic brake device, the electric actuator 10 is activated and the emergency stop device 200 operates, causing the car 1 to reach the top surface of the buffer at a speed within the range of the buffer's allowable collision speed.

In contrast, in the comparative example, the emergency stop device is not activated, and the collision speed of the car against the buffer is suppressed by the braking force of the electromagnetic brake device. For this reason, a buffer with a large collision speed tolerance is applied, anticipating a decrease in deceleration due to fluctuations in the braking force of the electromagnetic brake device.

In the terminal floor forced deceleration device according to the above embodiment, when the speed of the car 1 at the terminal floor (lowest floor) exceeds an overspeed threshold _Vth corresponding to the position of the car 1, the power supply to the hoist 4 is cut off and the electromagnetic brake device provided in the hoist is activated to decelerate the car, and when the magnitude of the deceleration of the car is smaller than a predetermined threshold _ath (=standard value _a0 ), the electric operator 10 is operated to operate the emergency stop device 200. As a result, even if the braking force of the electromagnetic brake device fluctuates due to aging or the like, the collision speed of the car with the buffer can be suppressed, and therefore the allowable collision speed value of the buffer can be reduced.

The present invention is not limited to the above-described embodiment, but includes various modified examples. For example, the above-described examples have been described in detail to clearly explain the present invention, and the present invention is not necessarily limited to having all of the configurations described. In addition, it is possible to add or delete other configurations or replace some of the configurations of the examples with other configurations.

For example, the position sensor 50 may be an image sensor or a rotation detector (e.g., a rotary encoder) that is provided in the car and rotates with the movement of the car. Also, any sensor that can detect the movement of the car, such as a speed sensor, may be used in place of the position sensor 50. When a speed sensor is used, the position detection unit 101 detects the position by integrating the speed.

The electric actuator 10 may be provided on the top of the car 1, as well as on the side or bottom of the car 1.

The elevator may be a so-called machine room-less elevator, in which the hoist and elevator control device are installed inside the hoistway.

1...car, 2...counterweight, 3...main rope, 4...hoist, 5...guide rail, 6...elevator control device, 7...tail cord, 10...electric actuator, 11...operating lever, 12...drive shaft, 13...drive spring, 14...fixed portion, 15...pressure member, 16...operating piece, 17...connecting piece, 18...operating piece, 19...operating shaft, 20...operating shaft, 21...lifting rod, 30...casing, 31...casing cover, 32...cover member, 33...plate-shaped member, 34...armature, 3 5...electromagnet, 36...feed screw, 37...motor, 38...bracket, 40...board, 41...support member, 42...support member, 50...position sensor, 100...safety controller, 101...position detection unit, 102...overspeed threshold calculation unit, 103...first overspeed determination unit, 104...power cutoff unit, 105...speed detection unit, 106...second overspeed determination unit, 107...electrical actuator operation unit, 108...deceleration calculation unit, 109...deceleration determination unit, 200...emergency stop device, 300...buffer

Claims

A terminal floor forced deceleration device that cuts off power supply to a hoist and activates a brake device to decelerate an elevator car having a buffer at the bottom of a hoistway when the speed of the elevator car exceeds a predetermined overspeed threshold set according to the position of the elevator car,
An emergency stop device provided in the car;
An electric operating device provided in the car for operating the safety device;
A safety control device that operates the electric actuator;
Equipped with
A terminal floor forced deceleration device characterized in that the safety control device operates the electric operator in accordance with the deceleration of the elevator car.
In the terminal stage forced deceleration device according to claim 1,
The terminal floor forced deceleration device is characterized in that the safety control device activates the electric actuator when the deceleration is smaller than a predetermined threshold value.
In the terminal stage forced deceleration device according to claim 2,
The safety control device includes:
A position detection unit that detects the position of the elevator car based on a detection signal of a movement sensor;
A speed detection unit that detects the speed of the car based on the detection signal of the movement sensor;
A deceleration calculation unit that calculates the deceleration of the car based on the speed of the car detected by the speed detection unit;
a deceleration determination unit that determines whether the deceleration calculated by the deceleration calculation unit is smaller than the predetermined threshold value;
A terminal floor forced deceleration device comprising:
In the terminal stage forced deceleration device according to claim 2,
A terminal floor forced deceleration device, characterized in that the predetermined threshold value is set to a standard value of the deceleration by the brake device.
In the terminal stage forced deceleration device according to claim 1,
The safety control device includes:
A terminal floor forced deceleration device characterized by having an overspeed threshold calculation unit that calculates the overspeed threshold based on the position of the elevator.
In the terminal stage forced deceleration device according to claim 1,
The safety control device includes:
When the speed of the car exceeds a predetermined first overspeed, the car is brought to an emergency stop by the brake device;
A terminal floor forced deceleration device characterized in that when the speed of the elevator car exceeds a predetermined second overspeed, the emergency stop device brings the elevator car to an emergency stop.
In the terminal stage forced deceleration device according to claim 1,
The elevator includes an elevator control device that controls a normal operation of the elevator car,
A terminal floor forced deceleration device characterized in that, during normal operation, the elevator car is controlled by the elevator control device to decelerate toward a stopping floor.
In the terminal stage forced deceleration device according to claim 1,
The terminal floor forced deceleration device characterized in that the electric actuator includes an electromagnet and a mechanism that drives the emergency stop device when the electromagnet is demagnetized.
In the terminal stage forced deceleration device according to claim 3,
The terminal floor forced deceleration device is characterized in that the movement sensor is an image sensor.