HK1132246B - Control system for elevator - Google Patents

Description

Elevator control system

Technical Field

The present invention relates to an elevator control system, and more particularly to an elevator control system that improves maintenance operations of high-lift elevators in a super high-rise building.

Background

In the conventional maintenance operation of an elevator, an operator operates a controller at his/her side to raise and lower an elevator car. The drive speed during maintenance operation is a low constant speed of about 15 to 30 m/min, which is a very low speed compared with the rated speed during normal operation, but it is characterized in that the elevator can be stopped at any place such as the middle between floors by operating the controller. The driving speed at the time of the maintenance operation is hereinafter referred to as a low-speed operation speed.

On the other hand, in addition to deceleration at the time of maintenance operation, the following forced deceleration method is disclosed in the elevator apparatus disclosed in patent document 1 and the terminal floor forced deceleration apparatus of the elevator disclosed in patent document 2: in normal operation, the speed is detected near the terminal floor (highest floor or lowest floor), and when the detected speed is higher than a preset speed, the elevator car is forcibly decelerated.

Further, patent document 3 discloses a method of trimming the floor height values in the ascending direction and the descending direction during normal operation and storing the trimmed values in a storage device in order to adjust the floor height value (the level value of each floor from the standard floor height).

Patent document 1: japanese laid-open patent publication No. 2001-354372

Patent document 2: japanese laid-open patent publication No. 2007-137554

Patent document 3: japanese unexamined patent publication Hei 5-246636

In the existing elevator, a limit switch is provided as a safety device for limiting the elevator car from descending below the lowest floor. After the limit switch is operated, a command for reducing the speed to zero is output to the drive motor, and the electromagnetic brake is operated. This method is used not only in normal operation but also in maintenance operation, and the elevator car stops after the travel command of the elevator car is changed stepwise to zero speed. In a high-lift elevator, since the length of the rope is very long, the spring coefficient (spring coefficient) of the rope is low, and the elevator car is likely to vibrate due to the speed change. Specifically, the coefficient of elasticity K [ N/m ] is set to

K＝K0*(x/h).........(1)

(wherein K0 represents the unit spring constant of each cable, x represents the number of cables, and h represents the cable length.)

Indicating that the spring constant decreases with increasing sling length h. Therefore, for example, in an elevator in which the length of the hoistway exceeds 400m, after the limit switch is operated, the elevator car stops after performing damping vibration in which the peak value of the amplitude is about several tens mm to one hundred and several tens mm. As a result, the final limit switch operation may be caused to be lower than the limit switch. The final limit switch is a safety device used in normal operation when a significant fault occurs causing the elevator car to pass far beyond the stopping position. Therefore, the final limit switch is set to cut off the power supply to the main circuit of the power converter to stop the power supply to the hoist and to prohibit the restart reset by the automatic operation when the final limit switch is operated. On the other hand, in order to suppress the amplitude of the damping vibration, it is conceivable to perform the operation in a state where the driving speed is further reduced, but in the case of a high-lift elevator, this method would result in an increase in the traveling time required for maintenance, thereby causing an adverse effect.

In patent documents 1 and 2, in normal operation, the speed is suppressed when the actual running speed of the elevator car exceeds a predetermined speed error range with respect to the running mode in which the elevator is stopped at the stop position. However, the forced deceleration operation is directed to an overspeed occurring when deceleration is performed in a normal operation, and the purpose of the forced deceleration operation is to increase the deceleration so as to stop the elevator car at a stop position at the highest floor or the lowest floor, and the techniques in patent documents 1 and 2 are not directed to a maintenance operation on the premise of a low-speed operation.

In patent document 3, since the layer height values in both the rising direction and the falling direction are stored in the storage device, the capacity increases and the reading method becomes complicated. In addition, it takes a lot of time to perform the reciprocating movement in the high-lift elevator.

Disclosure of Invention

The invention aims to provide an elevator control system related to maintenance operation of an elevator with high lift, according to which the elevator can be reliably stopped even if an error stopping operation is performed near the bottommost layer.

An elevator control system according to a preferred embodiment of the present invention includes: the elevator car ascends and descends in the ascending and descending channel, and the winch drives the elevator car to ascend and descend; and a control device for controlling the hoisting machine, wherein the elevator control system gives a zero speed command as a speed command of the elevator car and applies mechanical braking to the hoisting machine, when the elevator car reaches a first place beyond a standard stop position of a bottommost floor under a condition that the elevator car descends toward the bottommost floor according to a low-speed running speed for maintenance lower than a normal highest passenger-carrying running speed, wherein the elevator control system comprises: a speed suppression means for suppressing the speed command for maintenance operation lower than the low-speed operation speed for maintenance when the elevator car exceeds a set position higher than the first point; a final limit switch for emergency stopping of the elevator system when the elevator car in passenger travel reaches a point beyond a standard stopping position of the lowest floor by a prescribed distance, and further comprising: and a restarting means for automatically restarting the low-speed operation for maintenance when the measured position of the elevator car is located above an operating point of the final limit switch.

In a preferred embodiment of the present invention, the speed suppressing means includes speed command reducing means for reducing the speed command to a value lower than the speed command for the maintenance operation from a position immediately before the first point.

In a more specific embodiment of the present invention, the speed command reducing means is speed command reducing means for reducing a speed command stepwise to a speed command value lower than the speed command for the maintenance operation from a position immediately before the first point.

In another specific embodiment of the present invention, the speed command reduction means is speed command reduction means for gradually reducing the speed command from a position immediately before the first point to a predetermined speed or lower.

According to a preferred embodiment of the present invention, when the maintenance operation of the high-lift elevator is performed, the final limit switch operation due to the damping vibration of the elevator car can be prevented by the stepwise change of the speed command.

Other objects and features of the present invention will be described in the embodiments described below.

Drawings

Fig. 1 is a schematic view of a control system of an elevator in a first embodiment of the invention.

Fig. 2 is an example graph of speed command and elevator car displacement beyond the bottom floor in a typical maintenance run.

Fig. 3 is a flowchart of processing when a speed instruction is determined in the first embodiment of the present invention.

Fig. 4 is a first example of a maintenance operating speed command when traveling toward the bottommost layer in the first embodiment of the invention.

Fig. 5 is a second example of a maintenance operation speed command when traveling toward the lowermost layer in the first embodiment of the present invention.

Fig. 6 is a third example of a maintenance operation speed command when traveling toward the lowermost layer in the first embodiment of the present invention.

Fig. 7 is a process flow diagram of the second embodiment of the present invention.

Fig. 8 is a process flow diagram of the third embodiment of the present invention.

Fig. 9 is a schematic diagram for explaining an abnormal example of the shield plate inspection in the third embodiment, when the measurement value of the layer height value is written in the memory.

Fig. 10 is an explanatory diagram of an operation example when an error occurs in the measurement of the layer height value according to the third embodiment of the present invention.

In the figure: 1-elevator car, 2-hoist engine, 21-rotary encoder, 3-control device, 4-limit switch, 5-final limit switch, 6-controller for emergency operation, 71-7 n-shielding plate, 8-position detector, 9-speed regulator, 10-speed regulator rope.

Detailed Description

Embodiments of the present invention will be described below with reference to the drawings.

(example 1)

Fig. 1 is a schematic view of a control system of an elevator of a first embodiment of the present invention. As shown in the drawing, a hoist 2 including a drive motor for raising and lowering an elevator car 1 and a control device 3 for driving and controlling the hoist 2 are provided. In a normal state, the speed control of the drive motor is performed by comparing the speed command of the elevator with the output of the rotary encoder 21 for detecting the rotation speed of the hoisting machine 2.

As a safety device of an elevator terminal floor, there are provided a limit switch 4 that outputs a stop command for limiting the descent of the elevator car 1, and a final limit switch 5 disposed below the limit switch 4.

For the maintenance operation, a connector is provided in the elevator car 1, to which connector the controller 6 can be connected or from which connector it can be removed. When performing a maintenance operation, the maintenance person can communicate with the control device 3 after connecting the controller 6 to the connector, and can cause the elevator car 1 to ascend and descend at a low speed only while pressing the ascending button or the descending button of the controller 6.

In the hoistway, shielding plates 71-7 n as a reference for position correction for correcting the position of the elevator car when the elevator car 1 is raised and lowered are provided at respective floors, and a position detector 8 is provided in the elevator car 1, and the position of the elevator car 1 is detected by the position detector 8 in a direction facing the shielding plates 71-7 n.

In addition, a governor 9, which detects an abnormal overspeed of the elevator car 1, is directly connected to the elevator car 1 by a governor rope 10 and is driven by the elevator car 1. Thereby, the abnormal overspeed of the elevator car 1 at the initial stage is transmitted to the control device 3 to brake the elevator car, and at the abnormal overspeed at the final stage, the elevator car 1 is stopped by a wedge (wedge) between the brake and the guide rail.

In addition, when performing maintenance operation of the elevator, the operator operates the controller 6 at the side to raise and lower the elevator car, and operates the elevator at a maintenance operation speed (low-speed operation speed) which is a very low drive speed of about 15 to 30 m/min with respect to the rated speed in normal operation. The maintenance operation performed by the controller 6 is driven by an operation capable of selecting only the ascending operation/descending operation at a constant speed or the stopped state as described above, and the speed command value transmitted to the control device 3 is also changed stepwise in accordance with the operation.

The limit switch 4 is a safety device that operates when the elevator car 1 exceeds a stop position of a terminal floor (the highest floor and the lowest floor) by a predetermined distance, outputs a zero speed command as a speed command of the elevator, and operates a brake to prevent the elevator from further ascending or descending. The final limit switch 5 is a safety device that is provided at a position closer to the hoistway end portion side than the limit switch 4 and operates when the elevator car 1 exceeds a predetermined distance again, and the final limit switch 5 is a safety device provided to cope with a case where the elevator car greatly exceeds a stop position due to a serious failure occurring during normal operation. The final limit switch 5 is set to cut off power supply to the main circuit of the power converter to stop power supply to the hoist and to prohibit restart reset by automatic operation when the final limit switch is operated. In the case of normal operation, measures such as notification to a maintenance center or the like are taken.

Fig. 2 is an example graph of speed command and elevator car displacement beyond the bottom floor in a typical maintenance run. In the maintenance operation, the elevator is operated in accordance with a low speed command Vp at a constant speed, for example, a speed of 30 m/min or the like, in accordance with a descending operation command from the controller 6. Here, when the down travel command is output even after the stop position is exceeded, the limit switch 4 is operated when the elevator car 1 exceeds a predetermined distance. In this case, the speed command Vp is changed to zero stepwise, and the brake is actuated to stop the elevator. At this time, in the elevator with high lift, the car position Cp changes as shown in the figure with the time as the speed command Vp changes stepwise, and the elevator car 1 stops after undergoing damped vibration with the maximum amplitude x1 in the vertical direction. This is because, in an elevator with a high lift, as shown in formula (1), the spring coefficient of the suspension rope becomes small, and this effect starts to occur in an elevator with a hoistway length exceeding 200m, and when exceeding 400m, the maximum amplitude of the damping vibration may reach one hundred and several tens mm. As a result, the final limit switch 5 may be operated, and the restart reset may not be performed in an automatic operation manner, thereby possibly extending the maintenance time. As a countermeasure, it is conceivable to further reduce the operation speed of the maintenance, for example, to 15 m/etc., but if this method is adopted, the operation time when the high-lift lifting is performed becomes extremely long at the time of the maintenance, and the burden on the maintenance personnel increases.

Therefore, in the first embodiment, the speed command is changed when the prescribed distance is exceeded only when descending toward the lowermost layer in the maintenance operation.

Fig. 3 is a flowchart of processing when a speed instruction is determined in the first embodiment of the present invention. In step 31, it is determined whether or not there is a descending movement command. When there is no speed command in the descending direction, that is, when the vehicle is in the ascending operation or stopped state, a normal maintenance operation (ascending operation or stopping at a constant speed) command is output in step 32. On the other hand, when there is a travel command in the descending direction, it is determined in step 33 whether or not the position of the elevator car 1 from the limit switch 4 is higher than a predetermined position ho (position to be reached to the limit switch 4). When the elevator car 1 is about to reach the set position ho, a normal service travel speed command (constant speed: 30 m/min) is output in step 34. When the elevator car 1 exceeds the set position ho, a maintenance operation speed command (for example, 15 m/min) lower than the normal maintenance operation speed command is output as a speed command in step 35.

Fig. 4 is a first example of a maintenance operation speed command when traveling toward the lowermost layer in the first embodiment of the present invention.

In the first example of fig. 4, when the position of the elevator car 1 exceeds the set position ho, the speed command value controlled at a constant speed (30 m/min) until then is lowered to a maintenance operation speed command (for example, 15 m/min) lower than the normal maintenance operation speed command.

In this way, when a normal maintenance operation is performed at a speed of 30 m/min, the speed command value is reduced to 15 m/min when the descending operation is performed and the position of the elevator car 1 exceeds the set position ho. This processing reduces the variation width by, for example, about half of the variation width of the speed command value when the stop processing is performed by the limit switch 4, and therefore, the maximum value x2 of the amplitude when the elevator car 1 damps the vibration can be reduced. As a result, the final limit switch 5 can be prevented from operating without increasing the maintenance time.

Fig. 5 is a second example of the maintenance operation speed instruction while traveling toward the lowermost layer in the first embodiment of the present invention.

In the second example of fig. 5, when the position of the elevator car 1 exceeds the set position ho, the speed command value is decreased according to the position of the elevator car 1. That is, the speed command value Vp is reduced in a bulb shape in proportion to the position of the limit switch 4 and the distance between the elevator cars 1. As a result, as shown in the figure, the maximum amplitude of the vibration at the position Cp of the elevator car 1 generated when the speed command value Vp changes in a stepwise manner can be reduced to a very small amplitude of x3, and therefore the elevator car 1 can be stopped smoothly. As a result, the final limit switch operation due to the damping vibration can be prevented from occurring, and adverse effects such as an extension of maintenance time can be prevented from occurring.

In this example, the speed command value Vp is set to decrease in a bulb shape in proportion to the distance between the position of the limit switch 4 and the elevator car 1, but the speed command value Vp may be set to gradually decrease with the passage of time, and in this case, the same effect can be obtained, and a simpler circuit device can be realized.

Fig. 6 is a third example of the maintenance operation speed instruction when traveling toward the lowermost layer in the first embodiment of the present invention. In this example a method of forced deceleration of the elevator car speed is taken. That is, in the normal operation of the elevator, when the actual speed of the elevator car exceeds a predetermined speed error range with respect to the operation speed pattern in which the elevator is stopped at the stop position of the final floor (the highest floor and the lowest floor), the elevator car is forcibly decelerated. The operation speed pattern for forcibly decelerating the elevator car at this time is called a forced deceleration command, and is used at the time of deceleration (including the time of rising and falling) in normal operation.

In the third example of fig. 6, only when the maintenance operation is being performed, the forcible deceleration command is automatically switched to the forcible deceleration command when the forcible deceleration command is smaller than the speed command of a constant speed of 30 m/min. In this case, the maximum amplitude of the vibration generated when the speed command value changes in a stepwise manner can be reduced to a very small amplitude of x 4. As a result, the final operation of the limit switch 5 due to the damping vibration can be prevented, and adverse effects such as an extension of the maintenance time can be prevented.

(example 2)

Fig. 7 is a process flow diagram of the second embodiment of the present invention. The second embodiment is concerned with the final limit switch 5. The final limit switch 5 is a safety device provided to cope with a case where the elevator car greatly exceeds the stop position due to a serious failure in normal operation. Therefore, when the final limit switch 5 is set to be in operation, the power supply to the main circuit of the power conversion device is cut off to stop the power supply to the hoist and to prohibit the restart reset in the automatic operation.

The second embodiment is a safety measure when the high-lift elevator descends toward the lowermost floor and stops during maintenance operation, but unfortunately causes the final limit switch 5 to be actuated, although the first embodiment is employed.

First, when the final limit switch 5 is detected to be operated in step 71, the elevator is stopped in step 72 as in the case of a normal elevator. However, as described in the first embodiment, the final limit switch 5 may be operated due to the damping vibration generated when the elevator car 1 is stopped. Therefore, in step 73, after the predetermined time required for the convergence of the damping vibration has elapsed, the position of the elevator car 1 is measured again. In step 74, it is determined whether the measured position of the elevator car 1 is below the operating point of the final limit switch 5. When the position of the elevator car 1 is below the operating point of the final limit switch 5, the elevator is completely stopped in step 75. On the other hand, when the position of the elevator car 1 is above the operating point of the final limit switch 5, if the maintenance operation is being performed, the process of automatically restarting is performed in step 76.

The processing operation of the second embodiment has an effect that it is possible to prevent adverse effects such as an extension of maintenance time and to efficiently perform maintenance work.

(example 3)

Fig. 8 is a process flow diagram of the third embodiment of the present invention. The third embodiment is focused on layer height determination. The floor height measurement is performed to store the level value of each floor from the standard floor in the built-in storage device of the control device 3.

For example, as shown in fig. 1, the elevator car 1 is raised from a standard floor (for example, the lowest limit switch), and the number of pulses when passing through the shielding plates 71 to 7n is detected by the position detector 8, thereby determining the stop position of each floor. In this way, the floor height values of the shielding plates 71-7 n of all the floors up to the highest floor are stored. In general, the floor height measurement is performed at the time of commissioning before completion of the building, and the operation of the elevator car 1 at this time is performed at a low speed as in the low speed operation of the first embodiment.

In addition, the layer height measurement is generally performed from the lowermost layer toward the uppermost layer. However, since re-measurement is necessary when a detection abnormality or the like occurs, a long measurement time is inevitably required particularly in an elevator with a high lift because the speed of the elevator car 1 is low.

Fig. 9 is a schematic diagram for explaining an abnormal example of the shield plate inspection when the measurement value of the layer height value is written in the memory. As shown in fig. 9, a table corresponding to the number of floors is prepared in advance in the microcomputer. When the number of the shield plates 71-7 n detected in the layer height measurement is counted and the number of the shield plates does not match the number of the tables, it is determined that an abnormality has occurred, and a serviceman must exit the machine room and ride the elevator to check the installation condition of the shield plates. When the mounting error is corrected in the vicinity of the highest layer, it is needless to say that the layer height measurement is preferably performed from the highest layer.

Here, in the third embodiment of fig. 8, a method for measuring the floor height of an elevator capable of efficiently performing a high lift will be described.

First, in step 81, the position of the elevator car 1 before the floor height measurement is checked, and in step 82, it is determined whether the position of the elevator car 1 is closer to the highest floor or the lowest floor. When the distance is close to the bottommost floor, the elevator car 1 is moved to the standard floor of the bottommost floor in step 83, and the floor height measurement is performed while the elevator car 1 is raised in step 84.

Fig. 9(a) shows an example of the case where the measured value of the layer height value is written into the memory while rising from the bottommost layer in the third embodiment. Every time the position detector 8 passes through the shielding plates 71-7 n, a count value is stored in the storage device by an interrupt process or the like.

Referring back to fig. 8, when it is determined that the position of the elevator car 1 is closer to the highest floor in step 82, the elevator car 1 is moved to the standard floor of the highest floor in step 85, and the floor height measurement is performed while the elevator car 1 is lowered in step 86.

Fig. 9(B) is an example of writing the measured value of the layer height value into the memory while descending from the highest layer in the third embodiment. At this time, in order to store the measurement value of the same floor at the same address as in fig. 9(a), the measurement value is stored in the direction opposite to that of fig. 9 (a).

Then, in step 87, the number of the shield plates 71-7 n as the trigger signal for the layer height measurement process is compared with a predetermined number, and it is determined whether or not there is an abnormality in the measurement. If there is no abnormality, the layer height measurement is terminated, and if an abnormality is found, the process returns to step 82 to perform the process again.

Fig. 10 is an explanatory diagram of an operation example of the third embodiment when an error occurs in the measurement of the layer height value. In the third embodiment, it is selected whether starting from the highest floor or the lowest floor depending on the initial position of the elevator car 1. This can shorten the measurement time. Further, for example, when the floor height is measured from the lowest floor as a starting point and an abnormality is detected in step 87, in the normal floor height measurement, it is necessary to move the elevator car 1 to the lowest floor again and to perform the measurement again. However, as shown in the operation example of the third embodiment of fig. 10 in which an error occurs in the floor height value measurement, in the third embodiment, when the floor height measurement is performed with the lowest floor as the starting point, if an abnormality is detected in step 87, the measurement is performed again with the highest floor as the starting point. This has the effect of shortening the measurement time especially in high-lift elevators.

The embodiments of the present invention have been described above, but the present invention is not limited to the above embodiments, and it goes without saying that various modifications can be made within the scope not changing the gist of the present invention.

Claims (9)

1. An elevator control system, comprising: the elevator car ascends and descends in the ascending and descending channel, and the winch drives the elevator car to ascend and descend; and a control device for controlling the hoisting machine, wherein the elevator control system gives a zero speed as a speed of the elevator car and applies a mechanical brake to the hoisting machine, when the elevator car reaches a limit switch, which is a first point, beyond a predetermined distance from a standard stop position of a bottommost floor, under a condition that the elevator car descends toward the bottommost floor, in accordance with a low-speed running speed for maintenance, which is lower than a normal highest passenger-carrying running speed, the elevator control system is characterized by comprising:

a speed suppression means for suppressing a speed for maintenance operation of the elevator car to a speed lower than a low-speed operation speed for maintenance when the elevator car exceeds a set position higher than the first point;

a final limit switch which brings the elevator system to an emergency stop when the elevator car, which is carrying passengers, reaches a point which exceeds the standard stopping position of the lowermost floor by a prescribed distance,

further, the present invention also includes:

a detection unit that measures a position of the elevator car after a predetermined time elapses when the final limit switch is operated during low-speed operation for maintenance, and,

and a restarting means for automatically restarting the low-speed operation for maintenance when the measured position of the elevator car is above the operating point of the final limit switch.

2. Elevator control system according to claim 1,

the speed suppressing means includes speed command reducing means for reducing the speed of the elevator car to be lower than the speed for the maintenance operation from a position immediately before the elevator car reaches the first point.

3. Elevator control system according to claim 2,

the speed command reducing means is speed command reducing means for reducing the speed of the elevator car in a stepwise manner, and reduces the speed of the elevator car in a stepwise manner to a speed lower than the speed for the maintenance operation from a position immediately before the elevator car reaches the first point.

4. Elevator control system according to claim 2,

the speed command reduction means is speed command reduction means for gradually reducing the speed, and gradually reduces the speed of the elevator car from a position immediately before the elevator car reaches the first point to a predetermined speed or less.

5. Elevator control system according to claim 4,

the speed command reduction means is speed command reduction means for gradually reducing the speed, and gradually reduces the speed of the elevator car from a position immediately before the elevator car reaches the first point as time passes from the previous speed for the maintenance operation.

6. Elevator control system according to claim 1,

has a forced deceleration instruction generating unit which is used during passenger carrying operation and forcibly decelerates and stops the elevator which is going on descending operation on the terminal floor,

when the speed at which deceleration starts is lower than the maintenance operation speed, the speed command value is switched to a forced deceleration command.

7. Elevator control system according to claim 1,

the elevator control system is used for a high-lift elevator with the length of the lifting channel exceeding 200 m.

8. The elevator control system according to claim 1, characterized by comprising:

a position detection unit for confirming the position of the elevator cage during the floor height measuring operation, and,

and a floor height measuring operation command unit which moves the elevator car to the bottommost floor and then ascends to the topmost floor when the current position of the elevator car is closer to the bottommost floor and farther from the topmost floor, and moves the elevator car to the topmost floor and then descends to the bottommost floor when the current position of the elevator car is closer to the topmost floor and farther from the bottommost floor.

9. The elevator control system according to claim 8, characterized by having:

an abnormality detection means for detecting whether there is an abnormality in the floor height measurement after the floor height measurement from any one terminal floor of the highest floor or the lowest floor to another terminal floor is performed, and,

and a re-measurement instruction means for instructing a re-floor height measurement operation from the other terminal floor to the one terminal floor when the abnormality detection means detects an abnormality related to floor height measurement.