Device for elevator
A technology for elevators and stop devices, applied in transportation and packaging, elevators, etc., can solve the problems of slow braking force and time-consuming
Inactive Publication Date: 2007-12-19
MITSUBISHI ELECTRIC CORP
2 Cites 18 Cited by
AI-Extracted Technical Summary
Problems solved by technology
[0006] However, in the above-mentioned conventional brake device and brake control device, both of the basic emergency braking operation and the control of the b...
Method used
[0049] The cam plate 55 rotates about 90 degrees about the shaft 55a in response to a command signal from the fourth brake control unit 27, and changes from the state of FIG. 4 to the state of FIG. 5 . As a result, the second brake pad 52 is displaced upward relative to the car 1, and the distance between the second brake pad 52 and the second side surface of the car guide rail 3 (the distance before the start of the braking operation) changes from that shown in the figure. C0 narrows to C1 (C0>C1). As a result, the braking operation time of the emergency stop device 13 , that is, the time from when the circulation of the governor rope 15 is stopped to when...
Abstract
In an elevator apparatus, a brake control device has a first brake control portion, a second brake control portion, and a third brake control portion. The first brake control portion operates a hoisting machine brake to stop a ascending/descending body as an emergency measure when an abnormality is detected. The second brake control portion reduces a braking force of the hoisting machine brake when a deceleration of the ascending/descending body becomes equal to or higher than a predetermined value during an emergency braking operation of the hoisting machine brake. The third brake control portion monitors a slip speed of a main rope with respect to a drive sheave during emergency braking operation of the hoisting machine brake, and reduces a braking force of the hoisting machine brake when the slip speed of the main rope becomes equal to or higher than a predetermined value.
Application Domain
Elevators
Technology Topic
Automotive engineeringBrake control +3
Image
Examples
- Experimental program(1)
Example Embodiment
[0015] Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
[0016] Figure 1 is a configuration diagram showing an elevator apparatus according to Embodiment 1 of the present invention. The elevator car 1 and the counterweight 2 as an elevator body are raised and lowered in the hoistway. A car guide rail 3 that guides the lifting of the car 1 and a counterweight guide rail (not shown) that guides the lifting of the counterweight 2 are provided in the hoistway.
[0017] In the upper part of the hoistway, a hoist 4 for raising and lowering the car 1 and the counterweight 2 is provided. The winch 4 has a drive pulley 5, a motor 6 that rotates the drive pulley 5, a winch brake 7 that brakes the rotation of the drive pulley 5, and a pulley speed detection that detects the rotation speed of the drive pulley 5 (the rotation speed of the rotating shaft of the motor 6)器8. As the pulley speed detector 8, for example, a motor encoder that generates a pulse signal corresponding to the rotation speed of the rotating shaft of the electric motor 6 is used.
[0018] The hoist brake 7 has a brake rotor 9 such as a brake drum that rotates with the rotating shaft of the motor 6 and the drive pulley 5, a brake shoe 10 that contacts or separates from the brake rotor 9, and brakes A brake spring (not shown) that the shoe 10 presses against the brake rotor 9 and an electromagnet (not shown) that overcomes the brake spring and separates the brake shoe 10 from the brake rotor 9.
[0019] A deflector wheel 11 is arranged in the vicinity of the drive pulley 5. A plurality of main ropes 12 (only one is shown in the figure) are wound on the driving pulley 5 and the deflector wheel 11. In the hoistway, the car 1 and the counterweight 2 are suspended by the main rope 12. In the hoistway, the car 1 and the counterweight 2 are raised and lowered by the hoist 4 via the main rope 12.
[0020] In the lower part of the car 1, an emergency stop device (car brake) 13 that engages with the car guide rail 3 to stop the car 1 is installed. A governor 14 is provided on the upper part of the hoistway. The governor 14 is provided with a governor pulley, an overspeed detection (full text) switch, a rope catcher, and the like. A governor rope 15 is wound on the governor pulley. The two ends of the governor rope 15 are connected to the operating mechanism of the emergency stop device 13. The lower end of the governor rope 15 is wound on a tension pulley 16 arranged at the lower part of the hoistway.
[0021] When the car 1 rises and falls, the governor rope 15 circulates, and the governor pulley rotates at a rotation speed corresponding to the traveling speed of the car 1. In the governor 14, it is mechanically detected whether the traveling speed of the car 1 has reached an overspeed. As the detected overspeed, a first overspeed higher than the rated speed and a second overspeed higher than the first overspeed are set.
[0022] When the traveling speed of the car 1 reaches the first overspeed, the overspeed detection switch of the governor 14 is operated. When the overspeed detection switch is operated, the power supply to the electric motor 6 is cut off, and the rotation of the driving pulley 5 is braked by the hoisting machine brake 7, and the car 1 is stopped. When the traveling speed of the car 1 reaches the second overspeed, the governor rope 15 is grasped by the rope catcher of the governor 14 and the circulation of the governor rope 15 is stopped. When the circulation of the governor rope 15 is stopped, the emergency stop device 13 is operated to perform a braking operation.
[0023] The governor 14 is provided with a car speed detector 17 as an elevator speed detector that generates a signal corresponding to the rotation speed of the governor pulley, that is, the traveling speed of the car 1. As the car speed detector 17, for example, a governor encoder that generates a pulse signal corresponding to the rotation speed of a governor pulley is used.
[0024] A car buffer 18 and a counterweight buffer 19 are provided in the lower part (pit) in the hoistway. The car buffer 18 is arranged directly below the car 1 to buffer the impact when the car 1 collides with the bottom of the hoistway. The counterweight buffer 19 is arranged directly below the counterweight 2 to cushion the impact when the counterweight 2 collides with the bottom of the hoistway.
[0025] An upper terminal detection switch 20 is provided near the upper terminal floor in the hoistway. Near the lower terminal floor in the hoistway, a lower terminal detection switch 21 is provided. In the car 1, operating members 22 for operating terminal detection switches 20 and 21 are installed.
[0026] The hoisting machine brake 7 is controlled by the brake control device 23. The signals from the pulley speed detector 8, the car speed detector 17, and the terminal detection switches 20 and 21 are input to the brake control device 23.
[0027] FIG. 2 is a circuit diagram showing the brake control device 23 of FIG. 1. The brake control device 23 includes first to third brake control units 24 to 26 that control the hoisting machine brake 7 and a fourth brake control unit 27 that controls the braking operation time of the emergency stop device 13 independently.
[0028] The electromagnet of the hoisting machine brake 7 is provided with a brake coil (electromagnetic coil) 31. By energizing the brake coil 31 to excite the electromagnet, the brake shoe 10 is separated from the brake rotor 9. In addition, by controlling the current value of the brake coil 31, the degree of release of the hoisting machine brake 7 is controlled.
[0029] The circuit in which the discharge resistor 32 and the first discharge diode 33 are connected in series is connected in parallel with the brake coil 31. Furthermore, at both ends of the brake coil 31, a second discharge diode 35 is connected in parallel via the first and second electromagnetic relays 34a and 34b. In addition, the first relay 34 a side of the brake coil 31 is connected to the power source 36. In addition, the second relay 34 b side of the brake coil 31 is connected to the ground 38 of the power source 36 via the first semiconductor switch 37.
[0030] The first determining unit 39 controls the on/off of the first semiconductor switch 37. When the car 1 moves up and down, the first determination unit 39 closes the first semiconductor switch 37 to excite the brake coil 31, and the braking force of the hoisting machine brake 7 is released. When the car 1 is stopped, the first determining unit 39 turns off the first semiconductor switch 37 without energizing the brake coil 31, and causes the hoisting machine brake 7 to generate a braking force (standstill).
[0031] When an abnormality is detected in the elevator apparatus, the first determination unit 39 turns off the first semiconductor switch 37, releases the electromagnetic relays 34a and 34b, does not energize the brake coil 31, and causes the hoisting machine brake 7 to perform a braking operation. As a result, the car 1 is stopped urgently.
[0032] The function of the first determination unit 39 is realized by, for example, a first computer (not shown) of an elevator control device that controls the operation of the car 1. That is, in the first computer, a program for realizing the function of the first judging unit 39 is stored.
[0033] The first brake control unit (main control unit) 24 includes electromagnetic relays 34 a and 34 b, a second discharge diode 35, a first semiconductor switch 37, and a first determination unit 39. In addition, the first brake control unit 24 further includes a safety circuit (not shown) that releases the electromagnetic relays 34a and 34b in accordance with the abnormality of the elevator apparatus.
[0034] In addition, the first relay 34 a side of the brake coil 31 is connected to the power source 36 via the upper terminal detection switch 20. The second relay 34b side of the brake coil 31 is connected to the ground 38 via the lower terminal detection switch 21, the second semiconductor switch 40, and the current limiting resistor 41. The current limiting resistor 41 limits the magnitude of the current flowing through the brake coil 31.
[0035] When the car 1 is located near the terminal floor and is operated by the operating member 22, the terminal detection switches 20 and 21 are turned off, and the terminal detection switches 20 and 21 are turned off at other times. Therefore, when the car 1 is located outside the vicinity of the terminal floor, if the second semiconductor switch 40 is closed, even if the electromagnetic relays 34a and 34b and the first semiconductor switch 37 are opened, the brake coil 31 is excited. At this time, the current limiting resistor 41 limits the magnitude of the current flowing through the brake coil 31, so the electromagnetic force generated in the brake coil 31 is smaller than when the first brake control unit 24 performs brake release.
[0036] The OR logic unit 42 controls the on/off of the second semiconductor switch 40. The signal from the second determination unit 43 is input to one side of the OR logic unit 42. The output signal from the pulley speed detector 8 is input to the second determination unit 43. The second judging unit 43 obtains the car speed (to be precise, the sheave speed) based on the signal from the pulley speed detector 8, and obtains the car deceleration (absolute negative overspeed) by differentiating the car speed. value).
[0037] Then, the target deceleration (threshold value) set by the target deceleration setting unit 44 is input to the second determination unit 43. Then, the second determination unit 43 compares the car deceleration obtained from the signal from the pulley speed detector 8 with the target deceleration, and when the car deceleration reaches the target deceleration, outputs an ON signal to the OR logic unit 42. That is, when the car deceleration becomes equal to or greater than the predetermined value, the second determination unit 43 turns on the second semiconductor switch 40 to excite the brake coil 31, and reduces the braking force of the hoisting machine brake 7.
[0038] The second brake control unit (deceleration suppression unit) 25 has a second semiconductor switch 40, a current limiting resistor 41, or a logic unit 42, a second determination unit 43, and a target deceleration setting unit 44. For example, the functions of the OR logic unit 42, the second determination unit 43, and the target deceleration setting unit 44 are realized by a second computer (not shown) independent of the first determination unit 39. That is, in the second computer, a program for realizing the functions of the OR logic unit 42, the second determination unit 43, and the target deceleration setting unit 44 is stored.
[0039] The signal from the third determination unit 45 is input to the other side of the OR logic unit 42. The difference signal between the output signal from the car speed detector 17 and the output signal from the pulley speed detector 8 is input to the third determination unit 45. Then, the third determination unit 45 detects the sliding speed of the main rope 12 with respect to the drive pulley 5, and when the sliding speed reaches a predetermined value (threshold value), it outputs an ON signal to the OR logic unit 42. That is, when the sliding speed of the main rope 12 becomes equal to or greater than a predetermined value, the third determination unit 45 turns on the second semiconductor switch 40 to excite the brake coil 31 and reduce the braking force of the hoisting machine brake 7.
[0040] The third brake control unit (slip suppression unit) 26 has a second semiconductor switch 40, a current limiting resistor 41, or a logic unit 42, and a third determination unit 45. The function of the third determination unit 45 is realized by, for example, a second computer shared with the second determination unit 43. That is, in the second computer, a program for realizing the function of the third determination unit 45 is stored.
[0041] In addition, the ON signal from the third determination unit 45 when the sliding speed reaches a predetermined value is also input to the fourth brake control unit 27. When the fourth brake control unit 27 receives the ON signal from the third determination unit 45, it outputs a command signal for shortening the braking operation time to the emergency stop device 13. For example, the function of the fourth brake control unit (emergency stop control unit) 27 is realized by the second computer.
[0042] Next, FIG. 3 is a timing chart for explaining the operations of the second and third brake control units 25 and 26 of FIG. 2. In an emergency stop, the first brake control unit 24 turns off the electromagnetic relays 34a and 34b and the first semiconductor switch 37 (time T1). At this time, the torque of the motor 6 disappears, so the drive pulley 5 and the weight difference between the car 1 and the car 1 and the counterweight 2 are temporarily increased or decelerated according to the weight difference, and then the hoist brake 7 is applied to the drive pulley 5 Start deceleration (time T1 ~ T2).
[0043] During the deceleration of the drive pulley 5 and the car 1, the second brake control unit 25 monitors the deceleration of the drive pulley 5. Then, when the deceleration of the drive pulley 5 reaches the target deceleration or more, the second semiconductor switch 40 is turned on, and when the target deceleration is not reached, the second semiconductor switch 40 is turned off (timing T2 to T3). In FIG. 3, the second semiconductor switch 40 is repeatedly closed/opened to control the deceleration of the drive pulley 5 (interrupt switch control) only during the time T2 to T3.
[0044] During the deceleration of the drive pulley 5 and the car 1, the third brake control unit 26 monitors the sliding speed of the main rope 12 with respect to the drive pulley 5. When the sliding speed exceeds a predetermined value, the second semiconductor switch 40 is turned on (time T3). Thereby, the sliding speed of the main rope 12 is reduced (time T4 to T5), and the output from the third determination unit 45 is turned off (time T5). After that, the second and third brake control units 25 and 26 continue to monitor (time T5 to T6) until the drive pulley 5 and the car 1 stop.
[0045] However, when the car 1 arrives near the terminal floor and the terminal detection switches 20, 21 are operated during the deceleration of the car 1, the control of the second and third brake control units 25, 26 is invalidated, and the car Car 1 stops directly.
[0046] Next, Fig. 4 is a configuration diagram showing the emergency stop device 13 of Fig. 1. The emergency stop device 13 has first and second brake pads (wedge members) 51, 52 arranged on both sides of the car guide rail 3, a guide body 53 that guides the displacement of the brake pads 51, 52, and the first brake The moving piece 51 performs a braking operation with a working piece 54 and an elliptical cam plate 55 for displacing the second brake piece 52.
[0047] The working piece 54 is connected to the governor rope 15. When the descent speed of the car 1 reaches the second overspeed and the circulation of the governor rope 15 is stopped, the car 1 continues to descend, so that the work piece 54 rotates counterclockwise in FIG. 4 with the shaft 54a as the center. As a result, the first work piece 51 is displaced upward with respect to the car 1.
[0048] The guide body 53 is provided with first and second guide surfaces 53a and 53b facing each other. The interval between the guide surfaces 53a and 53b becomes narrower as it goes upward. Therefore, when the first brake pad 51 is lifted up by the work piece 54, it approaches the car guide rail 3 and is finally driven between the first guide surface 53 a and the first side surface of the car guide rail 3. As a result, the car 1 is only slightly displaced to the right in FIG. 4, that is, the car guide rail 3 is clamped between the first and second brake pads 51 and 52, and the car 1 is frictionally braked. .
[0049] The cam plate 55 rotates about 90 degrees around the shaft 55a in accordance with a command signal from the fourth brake control unit 27, and changes from the state of FIG. 4 to the state of FIG. 5. As a result, the second brake pad 52 is displaced upward with respect to the car 1, and the interval between the second brake pad 52 and the second side surface of the car guide rail 3 (the interval before the start of the braking operation) is changed from that of the figure. C0 narrows to C1 (C0>C1). As a result, the braking operation time of the emergency stop device 13, that is, the time from the stop of the circulation of the governor rope 15 to the generation of braking force, is shortened. In addition, for example, the cam plate 55 is rotated by a servo motor (not shown) provided in the car 1.
[0050] In such an elevator apparatus, while suppressing the deceleration during emergency braking, the main rope 12 can be prevented from slipping, and the emergency braking operation can be started more reliably and quickly. That is, the second brake control unit 25 suppresses the deceleration during emergency braking, so the ride feeling during emergency braking can be improved. In addition, the third brake control unit 26 suppresses the sliding of the main rope 12 during emergency braking, so the stopping distance of the car 1 can be shortened, and the vertical dimension of the hoistway can be shortened. Moreover, even when the slip of the main rope 12 becomes excessive, the speed of the car 1 is monitored by the governor 14, so the car 1 can be stopped more reliably.
[0051] In addition, when the sliding speed of the main rope 12 becomes more than a predetermined value, the fourth brake control unit 27 outputs a command signal for shortening the braking operation time of the emergency stop device 13, so that the stopping of the car 1 can be shortened more reliably. distance.
[0052] In addition, the emergency stop device 13 is provided with a cam plate 55 that rotates in response to a command signal from the fourth brake control unit 27 to displace the brake pad 52. Therefore, the emergency stop device 13 can be changed with a simple structure. Braking time.
[0053] Furthermore, the power supply system of the second semiconductor switch 40 controlled by the second and third brake control units 25, 26 and the power supply system of the first semiconductor switch 37 controlled by the first brake control unit 24 are different systems, and the second Since the semiconductor switch 40 is connected in series with the current limiting resistor 41, the magnitude of the current flowing through the brake coil 31 can be appropriately limited, and the control amount of the second and third brake control units 25, 26 to the hoisting machine brake 7 can be appropriately set.
[0054] In addition, when the car 1 reaches the vicinity of the terminal floor during the emergency braking operation of the hoist brake 7, the control by the second and third brake control units 25 and 26 is invalidated, so it is possible to change the position near the terminal floor. The car 1 is reliably stopped.
[0055] In addition, the second determination unit 43 may obtain the car deceleration based on the signal from the car speed detector 17 instead of the signal from the pulley speed detector 8.
[0056] Also, in the above example, the car speed detector 17 is provided in the governor 14. However, as shown in FIG. 6, for example, a deflector that generates a signal corresponding to the rotation speed of the deflector wheel 11 may be used. The wheel rotation detector 70 is used as a car speed detector.
[0057] Furthermore, as shown in FIG. 6, for example, the main rope speed detector 71 which generates a signal corresponding to the speed of the main rope 12 may be used as a car speed detector. As the main rope speed detector 71, the following measuring device can be used, which measures the speckle (speckle pattern) obtained by imaging the diffuse reflection light generated by irradiating the laser beam on the surface of the main rope 12 with a special camera. The moving speed of the main rope 12.
[0058] Furthermore, for example, as shown in FIG. 6, the camera apparatus 73 which photographs the main rope 12 may be used as a car speed detector.
[0059] As described above, by providing the car speed detector in addition to the governor 14, the detection accuracy of the car speed can be improved without depending on the flexibility (rigidity) of the governor rope 15.
[0060] Furthermore, in the above example, the sliding speed of the main rope 12 is obtained from the difference between the pulley speed and the car speed. However, as shown in FIG. 6, for example, it may be based on the microphone device 73 that detects the sliding sound of the main rope 12 Signal to estimate the sliding speed.
[0061] In addition, the sliding speed may be estimated based on a signal from a temperature sensor (not shown) that detects the temperature increase of the drive pulley 5 caused by the sliding of the main rope 12.
[0062] Furthermore, for example, as shown in FIG. 6, the sliding speed may be estimated based on a signal from the tension detection device 74 that detects the tension change of the main rope 12 caused by the sliding of the main rope 12.
[0063] Here, in FIG. 6, a state in which a plurality of car speed detectors and a plurality of sliding speed detectors are installed at the same time is shown, but of course, one car speed detector and one sliding speed detector may be selectively provided respectively. Speed detector.
[0064] In addition, in the above-mentioned example, the emergency stop device 13 is installed in the car 1, but the present invention can also be applied when the emergency stop device 13 is installed on the counterweight 2.
[0065] In addition, in the above example, the emergency stop device 13 that operates when the car 1 travels downward is shown, but the present invention can also be applied when an emergency stop device that operates when the elevator car 1 travels upward is used.
[0066] In addition, in the above-mentioned example, the first judging unit 39, the second and third judging units 43, 45 are constituted by different computers, but they may be constituted by a common computer. In addition, the second judging unit 43 and the third judging unit 45 may be composed of different computers.
[0067] Furthermore, the functions of the first to third determination units 39, 43, and 45 may be realized by a logic circuit that processes analog signals.
[0068] In addition, in the above-mentioned example, the hoist 4 is arranged at the upper part of the hoistway, but it may be arranged at other positions such as the lower part in the hoistway, for example.
[0069]Moreover, the roping method of the main rope is not particularly limited, and may be a 2:1 roping method, for example.
[0070] Furthermore, the main rope may be a rope having a circular cross-section, or a belt-shaped rope.
[0071] In addition, the hoisting machine brake may be a type that is embedded in the inner side of the drive pulley or the inner side of the motor rotor.
PUM
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