JPH05147867A - Controller of hydraulic elevator - Google Patents

Abstract

PURPOSE:To keep off any cavitation to be produced by a sudden drop of pressure in pressure oil at the side of a hydraulic pump at the time of starting the downward movement of a hydraulic elevator cage. CONSTITUTION:Each of pressure detectors 15, 16 is attached to a first circuit 6a, serving as a passage of pressure oil between a hydraulic pump 3 and an on-off valve 5, and a second circuit 6b serving as a passage of pressure oil between a hydraulic jack 1 and the on-off valve 5, and when both detected values of two pressure detectors 15 and 16 become equlized at the down operation starting of an elevator cage 2, the on-off valve 5 is opened on the basis of a command of a control part 14, thus the cage 2 starts its down travel.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control system for a hydraulic elevator, and more particularly to improvement of control operation at the start of a descent operation of a car.

[0002]

2. Description of the Related Art FIG. 3 is an overall configuration diagram showing an example of a conventional hydraulic elevator control device, and FIG. 4 is a longitudinal sectional view showing details of the on-off valve in FIG. 3 and 4, 1 is a hydraulic jack, 2 is a basket supported by the hydraulic jack 1,
Reference numeral 3 is a hydraulic pump capable of reversible rotation, and 4 is an electric motor for driving the hydraulic pump 3. Reference numeral 5 denotes an opening / closing valve, and a main chamber 52 and a back chamber 53 are formed inside the main body 51, and a valve body 54 is vertically slidably arranged in the main chamber 52, and a valve body 54 is provided between the two. Is sealed with an O-ring. The main chamber 52 of the on-off valve 5 is connected between the hydraulic jack 1 and the hydraulic pump 3, and the valve body 54 is operated up and down by the inflow and outflow of the pressure oil into the back chamber 53, so that the hydraulic jack 1 and the hydraulic pump Open and close the flow path of pressure oil between 3 and. The car 2 is opened when the car 2 is running and is closed when the car 2 is stopped.

Reference numeral 6 is a main circuit for pressure oil in which a hydraulic jack 1, an on-off valve 5 and a hydraulic pump 3 are connected in this order.
And the hydraulic pump 3 between the first circuit 6a and the hydraulic jack 1
A second circuit is provided between the switch and the on-off valve 5. 7 is a filter, 8
Is an oil tank. 9 is a pilot circuit, hydraulic jack 1
And a pressure oil inflow circuit 9a connecting the back chamber 53 of the on-off valve 5 and a pressure oil discharge circuit 9b connecting the back chamber 53 and the oil tank 8.

Reference numeral 10 is a normally open solenoid valve provided in the pressure oil inflow circuit 9a for opening and closing the pressure oil inflow circuit 9a, and 11 is provided in the pressure oil discharge circuit 9b for opening and closing the pressure oil discharge circuit 9b. Normally closed solenoid valves, 12 and 13 are variable throttle valves that adjust the flow rate of the pressure oil in the pressure oil inflow circuit 9a and the pressure oil discharge circuit 9b, and 14 is a control unit that controls the solenoid valves 10 and 11 and the electric motor 4. is there.

Next, the operation of this control device will be described with reference to FIGS. 3 and 4. When the car 2 is raised, pressure oil is supplied to the on-off valve 5 by the hydraulic pump 3 driven by the electric motor 4 according to a command from the control unit 14, and the solenoid valve 10 is closed and the solenoid valve 11 is closed according to a rising operation command for the car 2. The opening / closing valve 5 is opened according to the discharge speed of the pressure oil in the back chamber 53 to the oil tank 8 due to the resistance of the variable throttle valve 13, and the pressure oil from the first flow path 6a is opened by the opening / closing valve 5. It is supplied to the hydraulic jack 1 through the section, the main chamber 52, and the second flow path 6b, and the car 2 rises at a predetermined acceleration.

When a descending operation command is issued to the car 2, the solenoid valve 10 is closed and the solenoid valve 11 is opened by being urged by a signal from the control unit 14, so that the pressure oil in the back chamber 53 is changed by the variable throttle valve. The oil is discharged to the oil tank 8 through the pressure oil discharge circuit 9b at a speed according to the flow path resistance of 13. Further, since the electric motor 4 rotates at the same time as the lowering command from the control unit 14 drives the hydraulic pump 3 to discharge the pressure oil, a negative pressure is temporarily generated in the first circuit 6a. On-off valve 5 is back chamber 53 against pressure.
The pressure oil in the hydraulic jack 1 that starts to open due to the rise of the valve body 54 corresponding to the decrease in pressure due to the discharge of the pressure oil in the inside and is pressurized by the own weight of the car 2 is the second circuit 6b and the on-off valve 5. , The car 2 is discharged to the oil tank 8 through the first circuit 6a and the hydraulic pump 3, the car 2 starts to descend at an acceleration according to the change in the opening degree of the opening / closing valve 5, and when the opening / closing valve 5 is fully opened, the car 2 is at a constant speed. To descend.

Since the pressure oil discharged when the car 2 descends passes through the hydraulic pump 3 as described above, the electric motor 4 connected to this hydraulic pump 3 is operated by dynamic braking (regeneration),
The flow rate of the pressure oil to the oil tank 8 is suppressed, and the car 2 descends at a speed controlled by the electric motor 4. When the car 2 descends near the target floor, the electromagnetic valve 10 is opened and the electromagnetic valve 11 is closed in response to a command from the control unit 14, so the variable throttle valve 12 provided in the pressure oil inflow circuit 9a is closed. The supply of the pressure oil to the back chamber 53 according to the flow path resistance of the car starts, the car 2 starts decelerating corresponding to the speed in the closing direction of the valve body 54 due to this supply, and stops when the opening / closing valve 5 is fully closed. To do.

[0008]

In the conventional hydraulic elevator system as described above, when the car 2 starts descending,
Since the pressure oil in the back chamber 53 is discharged to the oil tank 8 through the electromagnetic valve 11, the pressure oil in the first circuit 6a is discharged to the oil tank 8 by the driving of the hydraulic pump 3 by the electric motor 4.
The inside of the first circuit 6a is in a temporary negative pressure state until the opening / closing valve 5 is opened, so that the gas dissolved in the pressure oil is released and cavitation occurs in which bubbles are generated. Bubbles due to this cavitation are generated by the hydraulic pump 3 and the first circuit 6a.
When the inner wall portion such as the above collides with an abnormally high impact force, there is a problem that vibration and noise are generated and the device and the seal portion are damaged. Further, in order to avoid the above-mentioned cavitation, for example, even when it is attempted to set a time point at which a control command is issued from the control unit 14 so as to start the electric motor 4 immediately after the opening / closing valve 5, the valve body 54 of the opening / closing valve 5 is controlled. There is also a problem that the movement cannot be mechanically measured from the outside.

The present invention has been made in order to solve the above-mentioned problems, and the first aspect of the present invention is provided when the car starts to descend.
An object of the present invention is to obtain a control device for a hydraulic elevator that can prevent vibration, noise, and damage to equipment and the like due to cavitation without causing cavitation in a circuit or a hydraulic pump.

[0010]

In a control device for a hydraulic elevator according to the present invention, an on-off valve for opening and closing a flow passage of pressure oil between a hydraulic pump and a hydraulic jack is provided on the hydraulic pump side when a car starts to descend. The control unit is provided with a pressure detecting means for transmitting a detection signal so as to open when the pressure becomes equal to the pressure on the hydraulic jack side.

[0011]

In the present invention, the pressure on the hydraulic pump side, which has been raised in advance when the descent operation of the car is started by discharging the pressure oil on the hydraulic jack side through the on-off valve and the hydraulic pump, is the pressure on the hydraulic jack side. When it becomes equal to, the on-off valve opens based on the command of the control unit that has detected the equal pressure state, and the descent traveling of the car starts.

[0012]

【Example】

Example 1. FIG. 1 is an overall configuration diagram of an embodiment of the present invention. The same parts as those in the conventional example of FIG. 3 are designated by the same reference numerals and the description thereof will be omitted. Reference numeral 15 is a pressure detector provided in the first circuit 6a, which detects the pressure between the hydraulic pump 3 and the on-off valve 5 and transmits it to the control unit 14. Also, 16 is the second
The pressure detector provided in the circuit 6b detects the pressure between the hydraulic jack 1 and the on-off valve 5 and transmits it to the control unit 14.

Next, the operation of the present invention configured as described above will be described with reference to FIGS. 1 and 2. However, basket 2
Since the operation during the ascending operation of is the same as the conventional example, it is omitted.
In addition, a portion of the operation of the car 2 during the descent operation that overlaps with the conventional example will be briefly described. First, when a descending operation command is issued to the car 2, the solenoid valve 10 is closed and the solenoid valve 11 is opened by being energized by a signal from the control unit 14,
The pressure oil in the back chamber 53 is discharged to the oil tank 8 through the pressure oil discharge circuit 9b at a speed according to the flow path resistance of the variable throttle valve 13. On the other hand, the electric motor 4 is rotated by a signal from the control unit 14 at the same time as the solenoid valves 10 and 11 are energized to drive the hydraulic pump 3 to change the hydraulic pressure in the first circuit 6a to point A as shown in FIG. Raise in the direction.

As described above, when the pressure oil in the back chamber 53 is being discharged and the pressure oil in the first circuit 6a is being increased, the pressure detectors 15 and 16 are respectively the hydraulic pump 3 and the on-off valve. 5, the pressure between the hydraulic jack 1 and the on-off valve 5 is detected and transmitted to the control unit 14. When the transmitted pressure detection values reach the point A in FIG.
4 issues a stop command to the electric motor 4, and at the same time, the opening / closing valve 5 starts to open, and the descending traveling of the car 2 starts at point B after time t.

The pressure oil in the hydraulic jack 1 is discharged to the oil tank 8 through the second circuit 6b, the opening / closing valve 5, the first circuit 6a and the hydraulic pump 3 by the weight of the saw 2, and the car 2
Accelerates until it reaches point C. When the point C is reached, the electric motor 4 connected to the hydraulic pump 3 is switched to the power generation control (regeneration) operation, and a constant braking action is applied to the rotation of the hydraulic pump 3, so that the car 2 shifts to constant speed traveling.

When the car 2 descends to the point D near the destination floor, the solenoid valves 10 and 11 are demagnetized by a command from the control unit 14 to open and close respectively, so that the second circuit 6b pressurizes oil. The supply of pressure oil to the back chamber 53 starts via the inflow circuit 9a, the car 2 decelerates and runs at a speed corresponding to the speed of the valve body 54 in the closing direction, and the car is at point E almost at the same time as the opening / closing valve 5 is fully closed. 2 stops.

[0017]

As described above, according to the present invention, the pressures on the hydraulic pump side and the hydraulic jack side of the on-off valve which is closed when the car starts to descend are detected, and when these pressures become equal, the on-off valve is opened. Since it was configured to open
It is possible to suppress cavitation caused by negative pressure on the hydraulic pump side before opening the on-off valve. Therefore, it is possible to obtain a hydraulic elevator control device capable of reliably preventing vibration and noise due to cavitation and damage to equipment.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of an embodiment of the present invention.

FIG. 2 is a diagram for explaining the operation of the present invention.

FIG. 3 is an overall configuration diagram of a conventional hydraulic elevator control device.

4 is a vertical cross-sectional view showing the structure of the on-off valve in FIG.

[Explanation of symbols]

 1 hydraulic jack 2 basket 3 hydraulic pump 4 electric motor 5 on-off valve 14 control unit 15 and 16 pressure detector

[Procedure amendment]

[Submission date] April 20, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0005

[Correction method] Change

[Correction content]

Next, the operation of this control device will be described with reference to FIGS. 3 and 4. When the car 2 is raised, pressure oil is supplied to the on-off valve 5 by the hydraulic pump 3 driven by the electric motor 4 according to a command from the control unit 14, and the solenoid valve 10 is closed and the solenoid valve 11 is closed according to a rising operation command for the car 2. The opening / closing valve 5 is opened according to the discharge speed of the pressure oil in the back chamber 53 to the oil tank 8 due to the resistance of the variable throttle valve 13, and the pressure oil from the first flow path 6a is opened by the opening / closing valve 5. It is supplied to the hydraulic jack 1 through the section, the main chamber 52, and the second circuit 6b, and the car 2 rises at a predetermined acceleration.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0006

[Correction method] Change

[Correction content]

When a descending operation command is issued to the car 2, the solenoid valve 10 is closed and the solenoid valve 11 is opened by being urged by a signal from the control unit 14, so that the pressure oil in the back chamber 53 is changed by the variable throttle valve. The oil is discharged to the oil tank 8 through the pressure oil discharge circuit 9b at a speed according to the flow path resistance of 13. Further, since the electric motor 4 rotates at the same time as the lowering command from the control unit 14 drives the hydraulic pump 3 to discharge the pressure oil, a negative pressure is temporarily generated in the first circuit 6a. On-off valve 5 is back chamber 53 against pressure.
The pressure oil in the hydraulic jack 1 that starts to open due to the rise of the valve body 54 corresponding to the decrease in pressure due to the discharge of the pressure oil in the inside and is pressurized by the own weight of the car 2 is the second circuit 6b and the on-off valve 5. , The car 2 is discharged to the oil tank 8 through the first circuit 6a and the hydraulic pump 3, the car 2 starts to descend at an acceleration according to the rotation speed of the electric motor 4, and after the opening / closing valve 5 is fully opened, the car 2 descends at a constant speed. ..

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0007

[Correction method] Change

[Correction content]

Since the pressure oil discharged when the car 2 descends passes through the hydraulic pump 3 as described above, the electric motor 4 connected to this hydraulic pump 3 is operated by dynamic braking (regeneration),
The flow rate of the pressure oil to the oil tank 8 is suppressed, and the car 2 descends at a speed controlled by the electric motor 4. When the car 2 descends near the destination floor, it is decelerated by the control of the electric motor 4 and then stopped. During deceleration of the car, the solenoid valve 10 is opened by a command from the control unit 14 and the solenoid valve 11 is closed. Therefore, the back chamber according to the flow path resistance of the variable throttle valve 12 provided in the pressure oil inflow circuit 9a. The supply of pressure oil to 53 starts, the valve body 54 moves in the closing direction by this supply, and then the on-off valve 5 is fully closed.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0013

[Correction method] Change

[Correction content]

Next, the operation of the present invention configured as described above will be described with reference to FIGS. 1 and 2. However, basket 2
Since the operation during the ascending operation of is the same as the conventional example, it is omitted.
In addition, a portion of the operation of the car 2 during the descent operation that overlaps with the conventional example will be briefly described. First, when a lowering operation command is issued to the car 2, the electric motor 4 rotates in the forward direction, the pressure of the first circuit 6a rises in the A direction, and when the pressure of the second circuit 6b becomes substantially the same as the pressure of the second circuit 6b, the control unit 14 The solenoid valve 10 is closed and the solenoid valve 11 is opened by being urged by the signal of
The pressure oil in the back chamber 53 is discharged to the oil tank 8 through the pressure oil discharge circuit 9b at a speed according to the flow path resistance of the variable throttle valve 13.

[Procedure Amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0014

[Correction method] Change

[Correction content]

As described above, when the pressure oil in the back chamber 53 is being discharged and the pressure oil in the first circuit 6a is being increased, the pressure detectors 15 and 16 are respectively the hydraulic pump 3 and the on-off valve. 5, the pressure between the hydraulic jack 1 and the on-off valve 5 is detected and transmitted to the control unit 14. When the transmitted pressure detection values reach the point A in FIG.
After the motor 4 is stopped, the reverse rotation command is continuously issued, and at the same time, the opening / closing valve 5 starts to open, and the descending traveling of the car 2 starts at point B after time t.

[Procedure correction 6]

[Document name to be amended] Statement

[Correction target item name] 0015

[Correction method] Change

[Correction content]

The pressure oil in the hydraulic jack 1 is discharged to the oil tank 8 through the second circuit 6b, the opening / closing valve 5, the first circuit 6a and the hydraulic pump 3, and the car 2 accelerates until it reaches point C. .. Immediately after the start of acceleration, the electric motor 4 connected to the hydraulic pump 3 is switched to the power generation control (regeneration) operation, and a constant braking action is applied to the rotation of the hydraulic pump 3.
Shifts to constant speed driving.

[Procedure Amendment 7]

[Document name to be amended] Statement

[Correction target item name] 0016

[Correction method] Change

[Correction content]

When the car 2 descends to the point D near the destination floor, the solenoid valves 10 and 11 are demagnetized by a command from the control unit 14 to open and close respectively, so that the second circuit 6b pressurizes oil. The supply of pressure oil to the back chamber 53 starts via the inflow circuit 9a, moves in the closing direction of the valve body 54, the car 2 is decelerated by the rotation speed control of the electric motor 4, and the opening / closing valve 5 is fully closed almost at the same time. Car 2 stops at point E.

[Procedure Amendment 8]

[Document name to be corrected] Drawing

[Name of item to be corrected] Fig. 4

[Correction method] Change

[Correction content]

[Figure 4]

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kamiya Kaguya No. 1 Hishimachi, Inazawa City Mitsubishi Electric Co., Ltd. Inazawa Works

Claims (2)

[Claims] 1. A car is raised by supplying pressure oil from a hydraulic pump driven by an electric motor to the hydraulic jack, and the car is lowered by discharging the hydraulic pressure in the hydraulic jack via the hydraulic pump. However, in a hydraulic elevator equipped with an on-off valve that opens between the hydraulic jack and the hydraulic pump when the car runs and closes when the car stops, the inlet side and the outlet of the on-off valve at the start of the descent of the car. A control device for a hydraulic elevator, characterized in that a pressure detecting means is provided for controlling so as to open when the pressure becomes equal to that on the side. 2. A first pressure detector is provided between the on-off valve and the hydraulic pump, and a second pressure detector is provided between the on-off valve and the hydraulic jack, and detection signals of these pressure detectors are supplied to a motor or the like. The control device for a hydraulic elevator according to claim 1, wherein the control device outputs a command to the control unit.