JPH0780642B2 - Control device for hydraulic elevator - Google Patents

Description

The present invention relates to a control device for a hydraulic elevator.

[Prior Art] FIG. 2 is a hydraulic circuit diagram of a control device for a hydraulic elevator similar to that shown as a conventional example in JP-A-57-126369.

In FIG. 2, 1 is a cage of a hydraulic elevator, 2 is a hydraulic jack for moving the cage 1 up and down, 3 is a hydraulic pump,
4 is an electric motor for driving the hydraulic pump 3, 5 is an oil tank, 6
Is a lift main circuit connecting the discharge side of the hydraulic pump 3 and the hydraulic jack 2, and 7 is a bypass circuit that branches from the lift main circuit 6 and opens into the oil tank 5 to form a part of the lift main circuit 6. 6a, the rising flow control valve, 8 is the back chamber of the rising flow control valve 7, 9 is the rising main circuit 6 and the rising flow control valve 7
Of the rising pilot circuit connected to the back chamber 8 and the oil tank 5, 10 is a rising solenoid valve provided in the rising pilot circuit 9, 11 is arranged on both sides of the rising solenoid valve 10 of the rising pilot circuit 9. 1st variable throttle, 12 is pilot circuit 9 for ascent
The second variable throttles arranged on both sides of the rising solenoid valve 10 are reference valves 13 provided on the hydraulic jack 2 side of the bypass circuit 6a of the rising main circuit 6 and the branch portion of the rising pilot circuit 9. 14 is a lowering main circuit opened to the oil tank 5 side connected to the hydraulic jack 2, 15 is a lowering flow control valve provided in the lowering main circuit 14, 17 is a lowering main circuit 14 and a lowering flow control valve 15
Of the descent pilot circuit connected to the back chamber 16 and the oil tank 5, 18 is a descent solenoid valve, 19 is a third variable throttle, 20 is a fourth variable throttle, the third variable throttle 19 and the fourth variable throttle. Variable aperture 20
Is provided in the descending pilot circuit 17 together with the descending solenoid valve 18 on both sides of this solenoid valve 18.

Next, the operation of the conventional example thus configured will be described.

When the car 1 is raised, the hydraulic pump 3 is driven to supply pressure oil to the rising main circuit 6, and the bypass circuit 6a initially causes the total flow rate of the pressure oil to rise.
And is returned to the oil tank 5. When the rising solenoid valve 10 is excited and the pressure oil of the rising main circuit 6 passes through the first variable throttle 11 of the rising pilot circuit 9 and flows into the back chamber 8 of the rising flow control valve 7, the rising flow rate is increased. The control valve 7 is controlled in the direction to close the passage of the bypass circuit 6a, and the amount of return oil to the oil tank 5 is reduced to increase the amount of pressure oil supplied from the raising main circuit 6 to the hydraulic jack 2. Is accelerated. Then, the passage of the ascending flow rate control valve 7 is fully closed, and from this time, the hydraulic oil at the full discharge flow rate of the hydraulic pump 3 is supplied to the hydraulic jack 2, and the car 1 travels upward at the maximum speed. Next, when the rising solenoid valve 10 is demagnetized, the pressure oil in the back chamber 8 of the rising flow rate control valve 7 passes through the second variable throttle 12 and flows out to the oil tank 5, so that the rising flow rate is increased. The control valve 7 is controlled to open the passage, and the oil tank 5 is bypassed.
By increasing the amount of oil recirculated from 6a and decreasing the amount of oil supplied to the hydraulic jack 2, the car 1 is decelerated and the rising flow control valve 7 fully opens this passage, so that the hydraulic pump 3 The pressure oil at the full discharge flow rate is returned to the oil tank 5, and the car 1 stops.

In addition, when the car 1 is lowered, the lowering solenoid valve 18
Is excited, the hydraulic pressure in the back chamber 16 of the descending flow control valve 15 passes through the fourth variable throttle 20 of the descending pilot circuit 17, flows out to the oil tank 5, and the passage of the descending flow control valve 15 is opened. The pressure oil in the hydraulic jack 2 is discharged to the oil tank 5, and the car 1 is lowered and accelerated. Then, the passage of the descending flow control valve 15 is fully opened, and from this time, the car 1 travels downward at the maximum speed. Next, when the descending solenoid valve 18 is demagnetized, the pressure oil from the descending main circuit 14 passes through the third variable throttle 19 and flows into the back chamber 16 of the descending flow rate control valve 15 to control the descending flow rate. The valve 15 moves in the direction to close the passage, the flow rate of the pressure oil passing through the descending flow rate control valve 15 is reduced, the car 1 is decelerated, and the descending flow rate control valve 15 is fully closed. , Car 1 stops.

[Problems to be Solved by the Invention] A conventional elevator control device is configured in this way,
The pressure in the hydraulic jack 2 fluctuates due to the fluctuation of the load due to the number of passengers in the car, etc., and accordingly, the rising main circuit 6 having the ascending flow control valve 7 or the descending flow control valve 15 or the descent. The pressure of the main circuit 14 for change also changes, and the flow rate of the pressure oil flowing through the ascending pilot circuit 9 and the descending pilot circuit 17 also changes. Therefore, the moving speed of the ascending flow rate control valve 7 or the descending flow rate control valve 15, that is, the passage opening / closing speed varies depending on the pressure in the hydraulic jack 2, and the car 1 is moved up and down to accelerate and decelerate. The slow speed travel (hereinafter simply referred to as “stop travel”) time for stopping the vehicle in conformity with the floor changes. Therefore, there are problems that the riding comfort is poor, the exercise efficiency is reduced, and the required power amount is increased.

Therefore, the present invention has been made to solve the above-described problems, and even if the pressure in the hydraulic jack changes, the car traveling speed is raised, the car is accelerated, decelerated, and stopped at a constant time. An object of the present invention is to provide a control device for a hydraulic elevator that can be used.

[Means for Solving Problems] A control device for a hydraulic elevator according to the present invention includes an ascending flow control valve connected to an ascending main circuit for supplying oil to a hydraulic jack to ascend the car, and the hydraulic pressure. A descending flow control valve connected to a descending main circuit for discharging oil from the jack to descend the car, and arranged between the ascending flow control valve, the descending flow control valve and the oil tank, and Leading the pressure in the hydraulic jack to the other, leading to the pressure on the downstream side of the ascending flow control valve and the descending flow control valve to the other, the spool valve operating with the pressure difference of both has a high pressure in the hydraulic jack. And a constant differential pressure reducing valve for reducing an orifice flowing from the ascending flow rate control valve and the descending flow rate control valve to the oil tank, and adjusting the hydraulic pressure of the ascending main circuit to the back chamber of the ascending flow control valve. With connecting to A rising pilot circuit connected to the main circuit between the back chamber of the rising flow control valve and the rising flow control valve and the constant difference pressure reducing valve;
The hydraulic pressure of the lowering main circuit is connected to the back chamber of the lowering flow control valve, and the main circuit between the lower chamber of the lowering flow control valve and the lowering flow control valve and the constant difference pressure reducing valve is connected. It is provided with at least one of the connected pilot circuits for descending.

[Operation] In the present invention, the hydraulic pressure of the rising main circuit is connected to the back chamber of the rising flow control valve, and the hydraulic pressure of the lowering main circuit is connected to the back chamber of the lowering flow control valve. Since the pilot circuit for use is connected between the ascending flow control valve, the descending flow control valve and the constant pressure reducing valve,
The pressure in the rising main circuit or the falling main circuit and the pressure at the downstream end of the rising pilot circuit or the falling pilot circuit are always constant without being affected by the pressure in the hydraulic jack, and the rising pilot circuit or The flow rate of the pressure oil that passes through the descending pilot circuit and the pressure oil that flows out of the ascending flow control valve or the descending flow control valve will also be constant, and even if the pressure inside the hydraulic jack changes, the car will rise and fall. Acceleration, deceleration, and stopping of traveling can be kept constant.

[Embodiment] An embodiment of the present invention will be described below with reference to FIG.

FIG. 1 is a hydraulic circuit diagram showing a control device for a hydraulic elevator according to an embodiment of the present invention. In the figure, the same reference numerals and symbols as those of the conventional example indicate the same or corresponding components as those of the conventional example, and therefore, duplicated description is omitted here.

In FIG. 1, 21 is a constant pressure reducing valve, 22 is a first pilot circuit that guides the pressure of the hydraulic jack 2 to the constant pressure reducing valve 21, and 23 is a pressure immediately before the constant pressure reducing valve 21 to the constant pressure reducing valve 21. A second pilot circuit 24, which leads, is a return main circuit provided with a constant pressure reducing valve 21. The reflux main circuit 24 is a portion where one end of the bypass circuit 6a, which constitutes a part of the rising main circuit 6, is connected to the downstream side of the rising flow control valve 7 and the downstream main circuit 14 to the falling flow control valve 15 downstream side. , And the other end is opened to the oil tank 5 via the constant pressure reducing valve 21. In addition, the pilot circuit 9 for rising
The downstream ends of the descending pilot circuits 17 are respectively connected to the bypass circuit 6a and the descending main circuit 14 immediately before the portion where the second pilot circuit 23 is connected to the return main circuit 24.

Further, the constant pressure reducing valve 21 is provided with a piston 21b on one side of the spool valve 21a on which the pressure in the hydraulic jack 2 by the first pilot circuit 22 acts, and at the other end of the spool valve 21a, a spring force of a spring 21e is provided. A piston 21c on which the pressure on the downstream side of the ascending flow rate control valve 7 and the descending flow rate control valve 15 by the second pilot circuit 23, that is, the pressure on the upstream side of the constant pressure reducing valve 21 of the reflux main circuit 24 acts is provided. When the pressure in the hydraulic jack 2 is high, the orifice 21d formed by the V-shaped notch provided in the spool valve 21 is reduced. The structure other than the above structure of this embodiment is the same as that shown in FIG.

Next, the operation of this embodiment will be described.

When the car 1 is raised, the hydraulic pump 3 is driven to supply pressure oil to the raising main circuit 6. At this time,
The oil is returned to the oil tank 5 through the constant pressure reducing valve 21 that has passed through the rising flow rate control valve 7. Then, the pressure in the hydraulic jack 2 is guided to one side of the constant pressure reducing valve 21 by the first pilot circuit 22, and the return main circuit 24 immediately before the constant pressure reducing valve 21 is guided to the other end by the second pilot circuit 23. The pressure and the spring force are acting.

As a result, the spool valve 21a of the constant pressure reducing valve 21 moves when the pressure inside the hydraulic jack 2 is high. Spool valve 21a
When the pressure in the hydraulic jack 2 is high, the orifice flowing from the ascending flow control valve and the descending flow control valve 15 to the oil tank 5 is reduced. The difference between the pressure in the hydraulic jack 2 and the pressure in the return main circuit 24 immediately before the constant difference pressure reducing valve 21 becomes substantially constant without being affected by the pressure change in the hydraulic jack 2. Therefore, when the car 1 is in the ascending operation, the pressure of the pressure oil discharged from the hydraulic pump 3, that is, the pressure in the ascending main circuit 6 becomes substantially the same as the pressure in the hydraulic jack 2. Also,
Since one end of the ascending pilot circuit 9 is connected to the ascending main circuit 6 and the other end immediately before the constant pressure reducing valve 21, the pressure difference between the both ends of the ascending pilot circuit 9 causes a pressure change in the hydraulic jack 2. Is not affected by the above, it becomes almost constant at all times, and the flow rate of the pressure oil passing through the ascending pilot circuit 9 becomes substantially constant. That is, when the rising solenoid valve 10 is excited, the flow rate of the pressure oil that passes through the rising pilot circuit 9 and flows into the back chamber 8 of the rising flow control valve 7 and the rising solenoid valve 10
When is demagnetized, the flow rate of the hydraulic pressure flowing out from the back chamber 8 of the rising flow control valve 7 is substantially constant regardless of the pressure inside the hydraulic jack 2. This means that the opening and closing time of the rising flow control valve 7 becomes constant, and the movement of the car 1 is almost constant regardless of the pressure in the hydraulic jack 2 during the ascending, decelerating and stopping traveling times during the ascending operation. It becomes a stable ascending driving run.

When the car 1 is moved down, the hydraulic jack 2
The pressure oil therein is discharged to the hydraulic tank 5 through the descending flow rate control valve 15 and the constant difference pressure reducing valve 21. At this time, the operation of the constant pressure reducing valve 21 is the same as during the ascending operation described above. Since one end of the descending pilot circuit 17 is connected to the descending main circuit 14 and the other end is connected immediately before the constant difference pressure reducing valve 21, the pressure difference between the both ends of the descending pilot circuit 17 is reduced to the hydraulic jack. Regardless of the pressure in 2, the flow rate of the pressure oil passing through the descending pilot circuit 17 is almost constant and is almost constant. That is, when the descending solenoid valve 18 is excited, the flow rate of pressure oil flowing from the back chamber 16 of the descending flow control valve 15 through the descending pilot circuit 17 and when the descending solenoid valve 18 is demagnetized. The flow rate of the pressure oil flowing into the back chamber 16 of the descending solenoid valve 18 is substantially constant regardless of the pressure inside the hydraulic jack 2. This means that the opening / closing time of the descending flow rate control valve 15 becomes almost constant, and the movement of the car 1 is almost constant regardless of the pressure in the hydraulic jack 2 during the descending operation. It becomes a stable descent running.

As described above, the control device for the hydraulic elevator according to the present embodiment,
An ascending flow control valve 7 connected to an ascending main circuit 6 for supplying oil to the hydraulic jack 2 to make the car 1 ascend, and a descending main circuit for discharging oil from the hydraulic jack 2 and making the car 1 descend. It is arranged between the descending flow rate control valve 15 connected to 14, the ascending flow rate control valve 7, the descending flow rate control valve 15 and the oil tank 5, and introduces the pressure in the hydraulic jack 2 to one side and to the other side. A spool valve 21a that guides the pressure on the downstream side of the ascending flow control valve 7 and the descending flow control valve 15 and operates with the pressure difference between them.
When the pressure in the hydraulic jack 2 is high, a constant differential pressure reducing valve 21 that reduces the orifices flowing from the rising flow control valve 7 and the falling flow control valve 15 to the oil tank 5, and the rising main circuit 6
Hydraulic pressure of the rising pilot circuit 9 connected to the back chamber 8 of the rising flow control valve 7 and the constant pressure reducing valve 21, and the hydraulic pressure of the lowering main circuit 14 to the back chamber 16 of the lowering flow control valve 15 The lowering pilot circuit 17 is connected to the pressure reducing valve 21.

Therefore, the ascending pilot circuit 9 in which the hydraulic pressure of the ascending main circuit 6 is connected to the back chamber 8 of the ascending flow rate control valve 7 is connected to the ascending flow rate control valve 7, the descending flow rate control valve 15, and the constant difference pressure reducing valve 21. In the meantime, the lowering pilot circuit 17 in which the hydraulic pressure of the lowering main circuit 14 is connected to the back chamber 16 of the lowering flow rate control valve 15 has a constant difference between the rising flow rate control valve 7 and the lowering flow rate control valve 15. Pressure reducing valve 21
And the pressure in the rising main circuit 7 or the lowering main circuit 15 and the pressure at the downstream end of the rising pilot circuit 6 or the lowering pilot circuit 14 in the hydraulic jack 2 respectively. The flow rate of pressure oil flowing through the ascending pilot circuit 9 or the descending pilot circuit 22 and flowing out from the ascending flow rate control valve 7 or the descending flow rate control valve 15 is almost constant without being affected by the pressure. Are also substantially constant, and even if the pressure in the hydraulic jack 2 changes, the acceleration, deceleration, and stop traveling times of the car 1 ascending and descending can be made substantially constant.

When the present invention is carried out, the present invention is not necessarily limited to this embodiment, and the ascending flow control valve 7 and the descending flow control valve 15 include the back chamber of one control valve, the control valve, and the constant valve. It is only necessary to determine the operation by connecting it to the main circuit between the differential pressure reducing valves, and the back chamber of the other control valve of the both ascending flow control valve 7 and the descending flow control valve 15. Ascending flow control valve 7 or descending flow control valve 15 and oil tank 5 corresponding to the ascending main circuit 6 and the descending main circuit 14.
It should be connected between.

[Effects of the Invention] As described above, according to the control device for a hydraulic elevator of the present invention, the oil pressure of the ascending main circuit is connected to the back chamber of the ascending flow control valve, and the ascending pilot circuit and the descending main circuit. Connect the lowering pilot circuit in which the hydraulic pressure of the above is connected to the back chamber of the lowering flow control valve between the rising flow control valve and the constant difference pressure reducing valve or between the lowering flow control valve and the constant difference pressure reducing valve, respectively. The pressure in the main circuit for lowering or the main circuit for lowering and the pressure at the downstream end of the pilot circuit for lowering or the pilot circuit for lowering are almost always constant without being affected by the pressure in the hydraulic jack. The flow rate of the pressure oil that passes through the pilot pilot circuit and the flow rate of the pressure oil that flows out from the rising flow control valve or the falling flow control valve becomes almost constant, and even if the pressure in the hydraulic jack changes, the cage The rise, fall, acceleration, deceleration, and stop traveling times of the vehicle can be made almost constant. Therefore, there is an effect that the stable riding comfort can be secured, the driving efficiency can be improved, and the required power amount can be reduced irrespective of the fluctuation of the load due to the number of passengers in the car.

[Brief description of drawings]

FIG. 1 is a hydraulic circuit diagram showing a hydraulic elevator control device according to an embodiment of the present invention, and FIG. 2 is a hydraulic circuit diagram showing a conventional hydraulic elevator control device. In the figure, 1 ... basket, 2 ... hydraulic jack, 5 ... oil tank, 6
...... Ascending main circuit, 6a ...... Bypass circuit, 7 ...... Ascending flow control valve, 8, 16 ...... Back chamber, 9 ...... Ascending pilot circuit, 10, 18 ...... Solenoid valve, 11, 12, 19,20 ... Variable diaphragm, 14 ...
… Main circuit for lowering, 15 …… Flow control valve for lowering, 17 …… Pilot circuit for lowering, 21 …… Constant pressure reducing valve, 22,23 …… First, 1st
2nd pilot circuit, 24 ... It is a return main circuit. In the drawings, the same reference numerals and symbols indicate the same or corresponding constituent parts.

Claims (1)

[Claims] 1. A raising flow control valve connected to a raising main circuit for supplying oil to a hydraulic jack to raise a car, and a lowering main circuit for discharging oil from the hydraulic jack to lower a car. Is installed between the descending flow rate control valve connected to the oil tank and the ascending flow rate control valve or the descending flow rate control valve and the oil tank, and the pressure in the hydraulic jack is introduced to one side and the rising flow rate to the other side. When the spool valve that guides the pressure on the downstream side of the control valve or the flow control valve for lowering and operates at a pressure difference between the two is high in the pressure inside the hydraulic jack, from the flow control valve for raising or the flow control valve for lowering A constant pressure reducing valve for reducing the orifice flowing to the oil tank, a rising pilot circuit connected to the main circuit between the back chamber of the rising flow rate control valve and the rising flow rate control valve and the constant pressure reducing valve, The descent A back chamber of the flow control valve, and at least one pilot circuit of a lowering pilot circuit connected to the main circuit between the lowering flow control valve and the constant difference pressure reducing valve. Control device.