Elevator device and control method for elevator device

Abstract

Disclosed are: an elevator device capable of performing a safe operation if an electric operation device fails; and a control method for the elevator device. This elevator device comprises: a cab; an emergency stop device provided to the cab; an electric operation unit (10) for operating the emergency stop device; a safety control device (103) for operating the electric operation unit upon detection of excessive speed of the cab; and an elevator control device (7) for controlling the operation of the cab. Upon detecting failure of the electric operation device, the elevator control device causes the cab to perform an emergency stop, and determines the operation state of the emergency stop device on the basis of an excessive speed detection signal sent from the safety control device.

Description

Elevator system and control method for elevator system

[0001] The present invention relates to an elevator system including an electric operating device that activates an emergency stop device, and a control method for this elevator system.

[0002] An electrically operated emergency stop device that does not use a governor rope has been proposed. A technology disclosed in Patent Document 1 is known as a conventional technology relating to such an emergency stop device.

[0003] In this conventional technology, a drive shaft that drives the safety device and an electric actuator that operates the drive shaft are provided on the car. The electric actuator has a moving element that is mechanically connected to the drive shaft and an electromagnet that attracts the moving element. The drive shaft is biased by a drive spring, but under normal circumstances, the electromagnet is energized and the moving element is attracted, so the movement of the drive shaft is restricted by the electric actuator.

[0004] In an emergency, the electromagnet is demagnetized, releasing the drive shaft, and the drive shaft is driven by the biasing force of the drive spring, which activates the emergency stop device and brings the car to an emergency stop.

[0005] Furthermore, when returning the emergency stop device to its normal state, the electromagnet is moved closer to the mover that moved in the emergency. The electromagnet is equipped with a feed nut that screws onto the feed screw shaft, and when the feed screw shaft is rotated by the motor, the electromagnet moves toward the mover. When the electromagnet comes into contact with the mover, the mover is attracted to the electromagnet. Furthermore, with the mover attracted to the electromagnet, the electromagnet is moved, returning the mover and electromagnet to their normal standby positions.

[0006] When maintaining an electric emergency stop device, it is necessary to inspect not only the mechanical parts such as the brakes (wedges) but also the electrical parts such as the electromagnets and motors equipped in the electric actuator for abnormalities and deterioration.

[0007] A technique described in Patent Document 2 is known as a conventional technique for improving the maintainability of an electrical device section.

[0008] This conventional technology includes a mover detection switch that detects the position of the mover, and a safety control device that detects a fault in the electric actuator based on a position detection signal from the mover detection switch. The safety control device commands the power cut-off of the first electromagnet when the electric actuator is on standby, and then detects a fault in the second electromagnet based on the position detection signal.

[0009] JP 2021-130550 A International Publication No. 2023 / 058198

[0010] The technique described in Patent Document 2 does not take into consideration the case where the electric operating device fails during normal operation of the elevator system.

[0011] Therefore, the present invention provides an elevator system that can operate safely even when an electric operating device fails, and a control method for an elevator system.

[0012] To solve the above problems, an elevator system according to the present invention includes a car, an emergency stop device provided in the car, an electric operating device that activates the emergency stop device, a safety control device that activates the electric operating device when it detects an overspeed of the car, and an elevator control device that controls the operation of the car. When the elevator control device detects a failure of the electric operating device, it brings the car to an emergency stop and determines the operating state of the emergency stop device based on an overspeed detection signal sent from the safety control device.

[0013] In order to solve the above problems, the present invention provides a control method for an elevator system including a car, an emergency stop device provided in the car, and an electric operating device for activating the emergency stop device. In this control method, when a failure of the electric operating device is detected, the car is brought to an emergency stop and the operating state of the emergency stop device is determined based on the car's overspeed state.

[0014] According to the present invention, safe operation of an elevator system equipped with an electric operator is possible.

[0015] Problems, configurations, and effects other than those described above will become apparent from the following description of the embodiments.

[0016] While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments and is not to be construed as limiting the scope of the invention.

[0017] An elevator system according to an embodiment of the present invention will be described below by way of example with reference to the drawings. In the drawings, the same reference numerals indicate the same components or components having similar functions.

[0018] FIG. 1 is a schematic diagram of an elevator system according to an embodiment of the present invention.

[0019] As shown in FIG. 1, the elevator system includes a car 1, speed sensors (5, 6), an electric operating device 10, a drive mechanism (12 to 20), a lifting rod 21, and a safety device 2.

[0020] The car 1 is suspended by a main rope (not shown) in a hoistway provided in a building, and is slidably engaged with a guide rail 4 via a guide device (not shown). When the main rope is frictionally driven by a drive device (hoisting machine: not shown), the car 1 moves up and down in the hoistway.

[0021] The speed sensor in this embodiment is provided on the car 1, and includes a rotation detector 6 and a roller 5 connected to the rotation shaft of the rotation detector 6. In this embodiment, the roller 5 is connected to the rotation shaft of the rotation detector 6 so that the rotation shaft of the roller 5 and the rotation shaft of the rotation detector 6 are coaxial. A rotary encoder, for example, can be used as the rotation detector 6.

[0022] The rollers 5 are in contact with the guide rails 4. Therefore, when the car 1 moves up and down, the rollers 5 rotate, which in turn rotates the rotation detector 6. A safety control device, which will be described later, monitors the running speed of the car 1 based on the rotation position signal output by the rotation detector 6 in accordance with the rotation.

[0023] An image sensor may be used as the speed sensor. In this case, the position and speed of the elevator car 1 are detected based on image information of the surface condition of the guide rail 4 acquired by the image sensor. For example, the speed is calculated from the moving distance of the image feature over a predetermined time period.

[0024] In this embodiment, the electric operator 10 is an electromagnetic operator and is disposed on the top of the car 1. The electromagnetic operator includes a movable piece or movable rod operated by, for example, a solenoid or an electromagnet. The electric operator 10 is actuated when a predetermined overspeed state of the car 1 is detected by the speed sensors (5, 6). At this time, the lifting rod 21 is pulled up by the drive mechanisms (12 to 20) mechanically connected to the operating lever 11. This causes the safety device 2 to enter a braking state.

[0025] The drive mechanisms (12 to 20) will be described later.

[0026] The safety devices 2 are arranged one on each side of the car 1. A pair of wedge-shaped brake shoes (not shown) provided on each safety device 2 are movable between a braking position and a non-braking position, and in the braking position they clamp the guide rail 4. Furthermore, when the brake shoes rise relative to the car 1 as the car 1 descends, a braking force is generated by the frictional force acting between the brake shoes and the guide rail 4. As a result, the safety devices 2 are activated when the car 1 enters an overspeed state, bringing the car 1 to an emergency stop.

[0027] The elevator system of this 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 (for example, a speed not exceeding 1.3 times the rated speed), the power supply to the drive device (hoisting machine) and the power supply to the control device that controls this drive device are cut off. Also, when the descent speed of the car 1 reaches a second overspeed (for example, a speed not exceeding 1.4 times the rated speed), the electric operating device 10 provided on the car 1 is electrically driven to activate the safety device 2, thereby bringing the car 1 to an emergency stop.

[0028] In this embodiment, the ropeless governor system is composed of the above-mentioned speed sensors (5, 6) and a safety control device that determines whether the car 1 is in an overspeed state based on the output signal of the speed sensor. This safety control device measures the speed of the car 1 based on the output signal of the speed sensor, and when it determines that the measured speed has reached a first overspeed, it outputs a command signal to cut off the power supply to the drive device (hoisting machine) and the power supply to the elevator control device that controls this drive device. Furthermore, when it determines that the measured speed has reached a second overspeed, the safety control device outputs a command signal to operate the electric operating device 10.

[0029] In this embodiment, although not shown in FIG. 1, the safety control device is disposed on the top of the car 1 together with the electric operating device 10.

[0030] The drive mechanism (12 to 20) that drives the lifting rod 21 will be described below.

[0031] The operating lever 11 and first operating piece 16 of the electric actuator 10 are connected to form a substantially T-shaped first link member. The operating lever 11 and first operating piece 16 form the head and foot of the T, respectively. The substantially T-shaped first link member is rotatably supported on the crosshead 50 via a first operating shaft 19 at the connection between the operating lever 11 and the first operating piece 16. One end (left side in the figure) of a pair of lifting rods 21 is connected to the end of the first operating piece 16, which forms the foot of the T, on the opposite side from the connection between the operating lever 11 and the first operating piece 16.

[0032] The connecting piece 17 and the second operating piece 18 are connected to form a substantially T-shaped second link member. The connecting piece 17 and the second operating piece 18 form the head and foot of the T, respectively. The substantially T-shaped second link member is rotatably supported on the crosshead 50 via the second operating shaft 20 at the connection portion 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 from the connection portion between the connecting piece 17 and the second operating piece 18.

[0033] An end of the operating lever 11 extending from the inside to the outside of the housing 30 and one of both ends of the connecting piece 17, which is closer to the top of the car 1 than the second operating shaft 20, are connected to one end (left side in the figure) and the other end (right side in the figure) of a drive shaft 12 lying on the car 1. The drive shaft 12 slidably passes through a fixed part 14 fixed to the crosshead 50. The drive shaft 12 also passes through a pressing member 15, which is fixed to the drive shaft 12. The pressing member 15 is located on the second link member (connecting piece 17, second operating piece 18) side of the fixed part 14. A drive spring 13, which is an elastic body, is located between the fixed part 14 and the pressing member 15, and the drive shaft 12 is inserted through the drive spring 13.

[0034] When the electric operator 10 is operated, that is, when the electromagnet is de-energized in this embodiment, the electromagnetic force that constrains the movement of the operating lever 11 against the biasing force of the drive spring 13 disappears, and the biasing force of the drive spring 13 applied to the pressing member 15 drives the drive shaft 12 along the longitudinal direction. As a result, the first link member (operating lever 11, first operating piece 16) rotates about the first operating shaft 19, and the second link member (connecting piece 17, second operating piece 18) rotates about the second operating shaft 20. 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.

[0035] Fig. 2 is a plan view showing the mechanical section of the electric actuator 10 in this embodiment in the installed state shown in Fig. 1. The mechanical section of the electric actuator 10 shown in Fig. 2 is housed in the housing 30 in Fig. 1.

[0036] FIG. 2 also shows the circuit configuration for driving and controlling the electric actuator 10.

[0037] In Fig. 2 (excluding the two-dot chain line), the safety device 2 (Fig. 1) is in a non-braking state, and the electric operating device 10 is in a standby state. In other words, the elevator system is in a normal operating state.

[0038] 2, in the standby state, the movers (34a, 34b, 34c), which are movable members connected to the operating lever 11, are attracted by electromagnetic force to the electromagnets 35a, 35b, whose coils are energized and excited. This restricts the movement of the movers against the biasing force F of the drive spring 13 acting on the movers via the drive shaft 12 (FIG. 1) and the operating lever 11. Therefore, the electric operating device 10 restricts the movement of the drive mechanism (12-20: FIG. 1) against the biasing force of the drive spring 13.

[0039] The mover has an attraction portion 34a that is attracted to the magnetic pole faces of the electromagnets 35a and 35b, and a support portion 34b that is fixed to the attraction portion 34a and to which the operating lever 11 is connected. The operating lever 11 is rotatably connected to the support portion 34b of the mover via a connection bracket 38. In the electric actuator 10, a mover detection switch 109 is provided at a position where the attraction portion 34a of the mover is located during standby.

[0040] The mover further has a cam portion 34c fixed to the suction portion 34a. When the mover is located at the standby position, a mover detection switch 109 is operated by the cam portion 34c. When the mover detection switch 109 is operated by the cam portion 34c, the mover detection switch 109 transitions from an ON state to an OFF state, or from an OFF state to an ON state. Therefore, it is possible to detect whether the mover is located at the standby position depending on the state of the mover detection switch 109. In this embodiment, the safety control device 103 determines whether the mover is located at the standby position based on the state of the mover detection switch 109.

[0041] In this embodiment, the mover detection switch 109 is in an ON state when it is operated by the cam portion 34c.

[0042] In this embodiment, at least the attracting portion 34a of the movers (34a, 34b, 34c) is made of a magnetic material, preferably a soft magnetic material such as low carbon steel or permalloy (iron-nickel alloy).

[0043] The other mechanisms (36, 37, 39, 41) in FIG. 2 will be described later.

[0044] The electromagnets 35a and 35b are excited by a DC power supply 300. The excitation circuit for the electromagnets 35a and 35b has the following configuration.

[0045] One end of the coil of electromagnet 35a is connected via fuse 107a to one end (electrical contact 105 side in FIG. 2 ) of the series connection of electrical contacts 104 and 105. One end of the coil of electromagnet 35b is connected via fuse 107b to one end (electrical contact 105 side in FIG. 2 ) of the series connection of electrical contacts 104 and 105. The other end (electrical contact 104 side in FIG. 2 ) of the series connection of electrical contacts 104 and 105 is connected to the high potential (positive terminal) of DC power supply 300.

[0046] The other ends of the coils of the electromagnets 35 a and 35 b are connected to each other and to the low potential (negative terminal) of the DC power supply 300 .

[0047] 2, the coils of the electromagnets 35a and 35b are connected in parallel via fuses 107a and 107b. One end of the parallel connection is connected to the high potential (positive terminal) of the DC power supply 300 via the series connection of electrical contacts 104 and 105. The other end of the parallel connection is connected to the low potential (negative terminal) of the DC power supply 300.

[0048] In this embodiment, the DC power supply 300 is composed of a rectifier and a power converter that convert AC power from the commercial single-phase AC power supply 200 into DC power. The commercial single-phase AC power supply 200 may be one phase of a commercial three-phase AC power supply 400 that supplies power to the hoisting machine 500 and the elevator control device 7 that drives and controls the hoisting machine 500.

[0049] The DC power supply 300 supplies power to operate the electromagnets 35a and 35b, the safety control device 103, the rotation detector 6, and the electrical contacts 104 and 105, as well as an answerback signal (S ０ ) as a power source for generating

[0050] A battery 111 is connected to the output of the DC power supply 300 in order to compensate for the power supply to the load for a short time when a power outage or voltage drop occurs. This allows the supply of DC power to be maintained in the event of an instantaneous power outage or instantaneous voltage drop in the commercial single-phase AC power supply 200.

[0051] Fuses 107a and 107b are provided in the excitation circuits to protect the electromagnets 35a and 35b from overcurrent, respectively.

[0052] The electrical contacts 104, 105 are controlled to be turned on and off by the safety control device 103. When the electric operator 10 is in a standby state, the safety control device 103 controls each of the electrical contacts 104, 105 to be in an on state. As a result, the coils of the electromagnets 35a, 35b are energized, and the electromagnets 35a, 35b generate electromagnetic forces.

[0053] Each of the electrical contacts 104, 105 is composed of a normally open contact provided in, for example, an electromagnetic relay, an electromagnetic contactor, or an electromagnetic switch. In the excitation circuit of the electromagnets 35a, 35b, multiple electrical contacts (two in FIG. 2) are connected in series. This means that even if an ON fault occurs in one contact when multiple electrical contacts are controlled to the OFF state to activate the safety device 2, as will be described later, the electromagnets are de-energized. This improves the operational reliability of the electric actuator 10. An ON fault may occur, for example, due to contact welding.

[0054] The other electrical equipment sections (37, 112) will be described later.

[0055] The answerback signal from the excitation circuit, which is input to the safety control device 103 via the signal line 106 shown in FIG. 2, indicates the potential at one end of the parallel connection of the coils of the electromagnets 35 a, 35 b, which is connected to the high potential (positive terminal) of the DC power supply 300 via the series connection of the electrical contacts 104, 105.

[0056] Therefore, if the electromagnets 35a, 35b are energized, the answerback signal indicates a high potential of the DC power supply 300, and if the electromagnets 35a, 35b are not energized, the answerback signal indicates a low potential of the DC power supply 300. Based on the potential indicated by such an answerback signal, the safety control device 103 detects the energized state of the electromagnets 35a, 35b and detects a failure of the electrical contacts 104, 105.

[0057] Next, the operation of the electric operating device 10 when the safety device 2 is activated will be described.

[0058] When the safety control device 103 detects a predetermined overspeed state (the second overspeed described above) of the car 1 based on the rotation position signal S from the rotation detector 6, it outputs an OFF command to each of the electrical contacts 104 and 105. The OFF command causes the electrical contacts 104 and 105 to transition from the ON state ( FIG. 2 ) to the OFF state. This stops the excitation of the electromagnets 35 a and 35 b, and the electromagnetic force acting on the movers (34 a, 34 b, 34 c) disappears. This releases the mover from its restraint position ( FIG. 2 ) due to the attraction of the attraction portion 34 a to the electromagnets 35 a and 35 b. The mover then moves from its standby position ( FIG. 2 ) to position P in the direction of the attraction force of the drive spring 13 (to the right in the figure) due to the biasing force of the drive spring 13 (F in FIG. 2 ). Note that in FIG. 2 , the mover after movement is indicated by a two-dot chain line.

[0059] As the restraint on the mover is released, the drive shaft 12 is driven by the biasing force of the drive spring 13 (FIG. 1) acting on the pressing member 15 (FIG. 1) of the drive shaft 12 in the direction from the fixed portion 14 (FIG. 1) toward the pressing member 15 (FIG. 1). When the drive shaft 12 is driven, the first link member (operating lever 11 and first operating piece 16: FIG. 1) connected to the drive shaft 12 rotates around the first operating shaft 19 (FIG. 1). This causes the lifting rod 21 (FIG. 1) connected to the first operating piece 16 to be pulled up. When the drive shaft 12 is driven, the second link member (connecting piece 17 and second operating piece 18: FIG. 1) connected to the drive shaft 12 rotates around the second operating shaft 20 (FIG. 1). This causes the lifting rod 21 (FIG. 1) connected to the second operating piece 18 to be pulled up.

[0060] Next, the return operation of the electric actuator 10 will be described.

[0061] In order to return the electric actuator 10 from an operating state in which the mover moves to position P by demagnetizing the electromagnets 35a and 35b to a standby state in which the mover is attracted to the electromagnets 35a and 35b as shown in FIG. 2, the mover (34a, 34b, 34c) is returned from the moving position (position P in FIG. 2) to the standby position (FIG. 2) by the mechanical parts (36, 37, 39, 41) and the electrical equipment part (37, 112), the description of which will be omitted, as will be described next.

[0062] The electric actuator 10 has a feed screw 36 for driving the mover. The feed screw 36 is coaxially connected to the rotation shaft of a motor 37 and rotatably supported by a support member 41. The electromagnets 35a and 35b are fixed to an electromagnet support plate 39 that includes a feed nut portion (not shown). The feed nut portion of the electromagnet support plate 39 is threadedly engaged with the feed screw 36. The feed screw 36 is rotated by the motor 37. The motor 37 is driven by a motor control device 112.

[0063] The motor control device 112 includes a drive circuit for the motor 37, and controls the rotation of the motor 37 in response to a control command from the elevator control device 7. The motor 37 may be either a DC motor or an AC motor.

[0064] The elevator control device 7 controls the operation of the car 1 and has information on the operating state of the elevator device. In this embodiment, as described above, the elevator control device 7 further has a function of controlling the motor 37 provided in the electric operating device 10.

[0065] In this embodiment, the elevator control device 7 includes a power converter 70 such as an inverter device that drives an electric motor 501 provided in the hoisting machine 500, a control unit that controls the electric motor 501 by controlling the power converter 70, a DC power supply for a brake device 502 provided in the hoisting machine 500, and a control unit that controls the opening and closing of the brake device 502. AC power is supplied to the elevator control device 7 from a commercial three-phase AC power supply 400 via normally open contacts provided in an electromagnetic contactor, an electromagnetic switch, etc. Normally, the normally open contacts are closed.

[0066] The elevator control device 7 controls the operation of the car 1 by controlling the motor 501 based on the detection signal of a rotation detector 510 (e.g., a rotary encoder) that detects the rotation of the motor 501 and the motor current detected by a current sensor 520.

[0067] When the safety control device 103 determines that the speed of the car 1 has reached the first overspeed, it outputs a command signal Sc, which in turn commands an electromagnetic contactor, an electromagnetic switch, or the like to open the normally open contact. This cuts off the power supply from the commercial three-phase AC power supply 400 to the elevator control device 7, stopping the drive control of the electric motor 501 and putting the brake device 502 into a braking state. This brings the car 1 to an emergency stop.

[0068] The recovery operation of the electric operating device 10 is executed when the elevator device is restored after the car 1 has come to an emergency stop due to the operation of the safety device 2 or the occurrence of a power outage.

[0069] When returning the electric operator 10 to the standby state, the elevator control device 7 sends a rotation command for the motor 37 to the motor control device 112. Upon receiving the rotation command, the motor control device 112 drives the motor 37 to rotate the feed screw 36. The rotating feed screw 36 and a feed nut portion provided on the electromagnet support plate 39 convert the rotation of the motor 37 into linear movement of the electromagnets 35a, 35b along the axial direction of the feed screw 36. As a result, the electromagnets 35a, 35b approach position P of the movers (34a, 34b, 34c) and come into contact with the movers.

[0070] The motor control device 112 monitors the motor current flowing through the motor 37 in order to control the motor 37. As described above, when the electromagnets 35a and 35b come into contact with the mover, the load on the motor 37 increases, and the motor current increases. When the motor current increases and exceeds a predetermined value, the motor control device 112 determines that the electromagnets 35a and 35b have come into contact with the mover. The motor control device 112 sends this determination result to the safety control device 103 and the elevator control device 7.

[0071] When the safety control device 103 receives the determination result from the motor control device 112, it outputs a control command signal S to each of the electrical contacts 104 and 105. １ , S ２The ON command signal is output as an ON command signal. The ON command signal causes the electrical contacts 104 and 105 to transition from an OFF state to an ON state. This causes the electromagnets 35a and 35b to be excited. The electromagnets 35a and 35b exert an electromagnetic force on the attracting portion 34a of the mover, causing it to be attracted to the electromagnets 35a and 35b.

[0072] When the elevator control device 7 receives the above-mentioned determination result from the motor control device 112, it sends a reverse rotation command for the motor 37 to the motor control device 112. Upon receiving the reverse rotation command, the motor control device 112 reverses the rotation direction of the motor 37, thereby rotating the feed screw 36 in the reverse direction. As a result, the mover attracted to the electromagnets 35a and 35b moves toward the standby position ( FIG. 2 ) together with the electromagnets 35a and 35b while receiving the biasing force of the drive spring 13.

[0073] The cam portion 34c of the mover (34a, 34b, 34c) is separated from the mover detection switch 109 from when the electric operator 10 is actuated and the mover (34a, 34b, 34c) moves to position P until immediately before the electric operator 10 completes its return operation. Therefore, at this time, the mover detection switch 109 is in the OFF state.

[0074] When the movers (34a, 34b, 34c) attracted to the electromagnets 35a, 35b reach the standby position from position P, the mover detection switch 109 is operated by the cam portion 34c provided on the mover. When the mover detection switch 109 is operated, the elevator control device 7 determines that the mover is located at the standby position. Based on this determination result, the elevator control device 7 sends a stop command for the motor 37 to the motor control device 112. Upon receiving the stop command, the motor control device 112 stops the rotation of the motor 37.

[0075] When the elevator control device 7 detects a failure of the electric operating device 10 during normal operation of the car 1 (non-overspeed state and non-power outage state), it stops the power supply from the power converter 70 to the electric motor 501 and activates the brake device 502 to bring the car 1 to an emergency stop.

[0076] In this embodiment, the elevator control device 7 detects a failure of the electric operator 10 by the mover detection switch 109. The elevator control device 7 monitors the on / off state of the mover detection switch 109, and when it detects a transition from the on state to the off state, that is, when it detects movement of the movers (34a, 34b, 34c) from the standby position during normal operation, it determines that a failure has occurred in the electric operator 10.

[0077] The elevator control device 7 has a rescue operation function, but because it may be difficult to move the car 1 depending on the operating state of the emergency stop device 2, before executing the rescue operation, the elevator control device 7 determines the operating state of the emergency stop device 2. In this embodiment, the elevator control device 7 determines the operating state of the emergency stop device 2 based on the presence or absence of an overspeed detection signal from the safety control device 103.

[0078] As described above, when the safety control device 103 determines that the descent speed of the car 1 measured by the speed sensors (5, 6) has reached the second overspeed, it outputs a command signal to operate the electric operating device 10. The safety control device 103 sends this command signal to the elevator control device 7 as an overspeed detection signal. The safety control device 103 and the elevator control device 7 are connected to each other so that they can communicate with each other.

[0079] If the elevator control device 7 does not receive an overspeed detection signal from the safety control device 103, it determines that the emergency stop device 2 is not activated or that it has activated due to a malfunction of the electric operator 10 rather than due to the car 1 overspeeding.

[0080] If the safety device 2 is not activated, the elevator control device can perform a rescue operation.

[0081] If the safety device 2 is activated due to a failure of the electric actuator 10, the elevator control device can execute rescue operation in the upward direction. Note that if the car 1 is operated in the downward direction, a wedge effect of the brake shoe of the safety device 2 occurs, causing the car 1 to stop moving and making rescue operation impossible.

[0082] Therefore, in this embodiment, when the elevator control device 7 does not receive an overspeed detection signal from the safety control device 103, it operates the car 1 upward from the stop position to the nearest floor as a rescue operation. After stopping the car at the nearest floor, the elevator control device 7 opens the car door and the hall door of the car 1.

[0083] 3 is a flowchart showing the safety operation of the elevator control device 7 in the event of a failure of the electric operating device 10 in this embodiment. The explanation will be made with reference to FIGS.

[0084] In this embodiment, the control unit in the elevator control device 7 includes a computer system such as a microcomputer, and the computer system executes a predetermined program to perform a safety operation.

[0085] In step S301, the elevator control device 7 determines whether the mover detection switch 109 is in the OFF state during normal operation of the car 1 (non-overspeed state and non-power outage state).

[0086] If the mover detection switch 109 transitions from the on state to the off state during normal operation of the car 1, the movers (34a, 34b, 34c) of the electric operator 10 are malfunctioning. Therefore, in step S301, the elevator control device 7 determines whether a failure has occurred in the electric operator 10.

[0087] If the elevator control device 7 determines that the mover detection switch 109 is not in the OFF state (NO in step S301), that is, if it determines that the mover detection switch 109 is in the ON state, it executes step S301 again. That is, the elevator control device 7 continues to monitor the occurrence of a failure in the electric operator 10. Furthermore, if the elevator control device 7 determines that the mover detection switch 109 is in the OFF state (YES in step S301), it then executes step S302.

[0088] In step S302, the elevator control device 7 brings the hoisting machine 500 to an emergency stop. In this case, the elevator control device 7 commands the electric motor 501 to stop and commands the brake device 502 to operate. This brings the car 1 to an emergency stop. After executing step S302, the elevator control device 7 then executes step S303.

[0089] In step S303, the elevator control device 7 determines whether the safety control device 103 has detected the above-mentioned second overspeed based on the overspeed detection signal from the safety control device 103. As described above, when the descent speed of the car 1 reaches the second overspeed, the emergency stop device 2 is activated by the electric operating device 10. Therefore, in step S303, the elevator control device 7 determines whether the emergency stop device 2 has not been activated or whether the emergency stop device 2 has been activated due to a malfunction of the electric operating device 10 rather than due to an overspeed of the car.

[0090] If the elevator control device 7 determines that the safety control device 103 has not detected the second overspeed (YES in step S303), that is, if it determines that the emergency stop device 2 has not been activated or that the emergency stop device 2 has been activated due to a malfunction of the electric operating device 10, it then executes step S304. If the elevator control device 7 determines that the safety control device 103 has detected the second overspeed (NO in step S303), that is, if it determines that the emergency stop device 2 has been activated due to the car 1 overspeeding, it ends the series of processes while keeping the car 1 in an emergency stop. Thereafter, the elevator device enters a state where it waits for work by an engineer.

[0091] In step S304, the elevator control device 7 determines whether the current position of the car 1 is between the top floor and the floor one floor before the top floor.

[0092] Rescue operation in the up and down directions is possible unless the emergency stop device 2 is activated, and rescue operation in the up direction is possible even if the emergency stop device 2 is activated due to a failure of the electric operating device 10. Therefore, when the elevator control device 7 determines that the safety control device 103 has not detected the second overspeed (YES in step S303), it can execute rescue operation in the up direction.

[0093] When nearest floor operation is performed as a rescue operation, if the position of the car 1 is between the top floor and the floor one floor before the top floor, the car 1 is operated to the top floor. If the car 1 stops at the top floor, it becomes difficult for an engineer to perform recovery work after the rescue operation. In particular, in this embodiment, the drive mechanism and electric operating device 10 of the emergency stop device 2 are provided on the car 1, making the recovery work even more difficult. Therefore, in this embodiment, before executing a rescue operation, it is determined whether the current position of the car 1 is between the top floor and the floor one floor before the top floor, or whether it is the nearest floor above the emergency stop position of the car 1.

[0094] If the elevator control device 7 determines that the position of the car 1 is not between the top floor and the floor one floor before the top floor, i.e., that the nearest floor is not the top floor (YES in step S304), it then executes step S305. Also, if the elevator control device 7 determines that the position of the car 1 is between the top floor and the floor one floor before the top floor, i.e., that the nearest floor is the top floor (NO in step S304), it ends the series of processes while keeping the car 1 in an emergency stop. The elevator device then enters a state where it waits for a technician to perform work.

[0095] In step S305, the elevator control device 7 releases the brake device 502 of the emergency-stopped car 1 and resumes operation of the car 1 in the upward (UP) direction toward the nearest floor. After executing step S305, the elevator control device 7 then executes step S306.

[0096] In step S306, the elevator control device 7 drives the car door of the car 1 that has arrived and stopped at the nearest floor to open the car door and the hall door that engages with the car door, and then places the car 1 in a stopped state at the nearest floor. After executing step S306, the elevator control device 7 ends the series of processes. The elevator device then enters a state of waiting for work by an engineer.

[0097] According to the above-described embodiment, if a failure of the electric operating device 10 is detected during normal operation of the car 1, the car 1 is brought to an emergency stop, and the operating state of the emergency stop device is determined based on whether or not an overspeed state of the car 1 is detected. This enables appropriate safety operation of the elevator system (in this embodiment, rescue operation in the upward direction) and appropriate safety measures for the elevator system after the emergency stop. Therefore, the safety of an elevator system equipped with an electric emergency stop device is improved.

[0098] The present invention is not limited to the above-described embodiments and includes various modifications. For example, the above-described embodiments have been described in detail to clearly explain the present invention, and the present invention is not necessarily limited to those including all of the described configurations. Furthermore, it is possible to add, delete, or replace part of the configuration of the embodiments with other configurations.

[0099] For example, if reliability can be ensured, only one electrical contact may be required.

[0100] Alternatively, the answerback signal from the excitation circuit may be an excitation current from a DC power supply. In this case, the excitation current is detected by a current sensor, and when the excitation current is detected, the safety control device determines that the electrical contacts have an ON failure. When the detected current value is zero, the safety control device determines that the electrical contacts are normal.

[0101] Moreover, instead of the mover detection switch 109, other position detection sensors, such as a photoelectric position sensor, a magnetic position sensor, or a proximity sensor (capacitive or inductive), may be used.

[0102] In addition, the electric operating device 10 may be provided not only at the upper part of the elevator car 1 but also at the lower part or side part.

[0103] The elevator system may have a machine room, or may be a so-called machine room-less elevator that does not have a machine room.

[0104] DESCRIPTION OF SYMBOLS 1...car, 2...emergency stop device, 4...guide rail, 5...roller, 6...rotation detector, 7...elevator control device, 10...electric operator, 11...operating lever, 12...drive shaft, 13...drive spring, 14...fixing portion, 15...pressure member, 16...first operating piece, 17...connecting piece, 18...second operating piece, 19...first operating shaft, 20...second operating shaft, 21...lifting rod, 30...casing, 34a...suction portion, 34b...support portion, 34c...cam portion, 35a, 35b...electromagnet, 36...feed screw, 37...motor , 38...Connection bracket, 39...Electromagnet support plate, 41...Support member, 50...Crosshead, 70...Power converter, 103...Safety control device, 104, 105...Electrical contacts, 106...Signal line, 107a, 107b...Fuse, 109...Motor detection switch, 111...Battery, 112...Motor control device, 200...Commercial single-phase AC power supply, 300...DC power supply, 400...Commercial three-phase AC power supply, 500...Hoisting machine, 501...Electric motor, 502...Brake device, 510...Rotation detector, 520...Current sensor

Claims

1. An elevator apparatus comprising a car, an emergency stop device provided in the car, an electric operator for operating the emergency stop device, a safety control device for operating the electric operator when detecting an overspeed of the car, and an elevator control device for controlling the operation of the car, wherein the elevator control device stops the car emergently when detecting a failure of the electric operator, and determines an operating state of the emergency stop device based on an overspeed detection signal sent from the safety control device.

2. The elevator apparatus according to claim 1, wherein the elevator control device executes a rescue operation in the upward direction of the car when not receiving the overspeed detection signal.

3. The elevator apparatus according to claim 2, wherein the elevator control device keeps the car stopped when receiving the overspeed detection signal.

4. The elevator apparatus according to claim 2, wherein the rescue operation is an operation to the nearest floor.

5. The elevator apparatus according to claim 4, wherein the nearest floor is not the top floor.

6. The elevator apparatus according to claim 1, comprising a drive mechanism for driving the emergency stop device, wherein the electric operator operates the drive mechanism, and the electric operator includes a mover mechanically connected to the drive mechanism, and an electromagnet that attracts the mover at a standby position of the mover to restrain the movement of the drive mechanism and is demagnetized when the speed of the car reaches a predetermined overspeed to operate the drive mechanism.

7. The elevator apparatus according to claim 6, wherein the elevator control device detects the failure of the electric operator according to the movement of the mover from the standby position.

8. In a control method of an elevator apparatus including a car, an emergency stop device provided in the car, and an electric operator that operates the emergency stop device, when a failure of the electric operator is detected, the car is brought to an emergency stop, and based on an overspeed state of the car, an operating state of the emergency stop device is determined. A control method of an elevator apparatus is characterized by this.

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