JPH11246136A - Hydraulic elevator device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To safely start/stop an elevator by forcedly closing a main check valve by introducing pressure oil introduced to an outlet of a selector valve into a pilot pressure chamber of the main check valve at car stopping time. SOLUTION: Before the object floor, a car 1 transfers to a constant low speed movement according to a variable speed control pattern, and when a position detecting switch of the object floor detects an arrival of the car, a controller 12 issues a stopping command signal to further reduce a speed of an inverter motor M. Therefore, a delivery quantity of a hydraulic pump 4 is reduced to stop the car 1. While, excitation of a solenoid device A is cut off after a prescribed time from output time of the stopping command signal. At this time, a main check valve 5 gradually reduces in the opening accroding to reduction in a flow rate, so that valve closing operation can be performed without giving a shock to the car 1 at stopping operation time by de- energization of the solenoid device A by properly selecting the speed setting at constant low speed movement time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic elevator system, and more particularly, to controlling the supply and discharge of pressure oil to and from a hydraulic jack for raising and lowering a car by a hydraulic pump driven by a forward / reverse variable speed motor and an electromagnetically operated hydraulic on / off valve device. The present invention relates to a hydraulic elevator apparatus of the type described below.

[0002]

2. Description of the Related Art As this type of hydraulic elevator system,
For example, one disclosed in Japanese Patent Publication No. 7-42057 is known. This conventional hydraulic elevator apparatus includes a hydraulic jack that drives a car up and down, an electric motor whose forward and reverse variable speed is controlled by an inverter, a hydraulic pump driven by the electric motor, and a hydraulic pump and the hydraulic jack. A command signal is given to the electromagnetically operated hydraulic on / off valve device for controlling the opening and closing of the main flow path between the hydraulic motor and the electromagnetically operated hydraulic on / off valve device so that the pressure on the hydraulic jack side and the pressure on the hydraulic pump side become substantially equal. And a controller for controlling the operating speed of the hydraulic jack by controlling the supply / discharge flow rate of a hydraulic pump by forward / reverse variable speed control of the electric motor.

[0003] Electromagnetically operated hydraulic on-off valve devices are often
For a start / stop operation, a hydraulic pilot operated poppet valve type main check valve and the pilot pressure chamber of this main check valve are connected to the tank line when opened, and the hydraulic jack side pressure is introduced into the pilot pressure chamber when closed. And an electromagnetic valve.

[0004]

In the conventional hydraulic elevator apparatus described above, when the car is stopped, the pilot pressure chamber of the main check valve is closed by the pressure of the hydraulic jack acting on the pilot pressure chamber. However, if a malfunction occurs in the control device for controlling the hydraulic pump at a variable speed and abnormal operation occurs during stoppage of the car, especially when the hydraulic pump malfunctions in the upward direction of the car, the pressure discharged from the hydraulic pump When the oil pressure increases, the main check valve may be pushed open to raise the car. Further, in the conventional hydraulic elevator apparatus, when starting the car, it is necessary to start the operation of the hydraulic jack at a timing when the pressure on the hydraulic pump side of the main check valve is substantially equal to the pressure on the hydraulic jack side. Since hydraulic detectors are provided on the hydraulic jack side and the hydraulic pump side of the main flow path for detection, not only are multiple expensive hydraulic detectors required, but also electronic comparison of detected pressure values The configuration of the control system such as processing becomes complicated, and there is a problem that the price of the apparatus increases.

Accordingly, a major object of the present invention is to solve the above-mentioned disadvantages and disadvantages of the prior art, and to prevent the movement of the car even when the hydraulic pump abnormally operates in the upward direction while the car is stopped. An object of the present invention is to provide a safe hydraulic elevator device that can surely prevent the problem. Also,
In addition to this safety, there is no need for a hydraulic pressure detector to open the main check valve in the absence of a pressure difference and an electronic comparison processing device of the detected value to eliminate shocks at the time of start-up. It is another object of the present invention to provide a hydraulic elevator apparatus which can be started and stopped and a selector valve having a pressure state detecting function which can be used for the hydraulic elevator apparatus.

[0006]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, a hydraulic elevator apparatus according to the present invention has a hydraulic jack for driving a car up and down, an electric motor whose forward / reverse variable speed is controlled, and a motor driven by the electric motor. A hydraulic pump, a solenoid operated hydraulic on / off valve device for controlling the opening and closing of a main flow path between the hydraulic pump and the hydraulic jack, and a command signal to the electric motor and the electromagnetically operated hydraulic on / off valve device. When the pressures on the hydraulic jack side and the hydraulic pump side become substantially equal, the electromagnetically operated hydraulic on / off valve device is opened, and the operation of the hydraulic jack is controlled by controlling the supply / discharge flow rate of the hydraulic pump by forward / reverse variable speed control of the electric motor. Having a control device for controlling the speed, in particular, the electromagnetically operated hydraulic on-off valve device is disposed in a main flow path between a hydraulic pump and a hydraulic jack, and a flow rate when the valve is opened. A hydraulic pilot operated main check valve that opens at a corresponding opening degree, a selector valve that selects the hydraulic oil on the hydraulic jack side or the hydraulic pump side of the main flow path, whichever is the higher pressure side, and guides it to its own outlet; A start / stop operation solenoid valve controlled by the control device at the time of starting and stopping the car, the start / stop operation solenoid valve includes:
At the time of starting the car, the pilot pressure chamber of the main check valve takes a switching position to communicate with the main flow path downstream of the main check valve, and at the time of stopping the car, the pressure oil guided to the outlet of the selector valve is discharged. A switching position for introducing the pilot valve into the pilot pressure chamber of the main check valve and forcibly closing the main check valve is provided.

According to a preferred aspect of the present invention, the selector valve includes switch means for generating an electric signal output when the hydraulic pump side pressure of the main flow path becomes higher than the hydraulic jack side pressure.

The present invention also provides a selector valve capable of detecting a high or low pressure state between two ports usable in the hydraulic elevator apparatus as described above, wherein the selector valve comprises a first and a second valve. A valve body having two inlet ports and one outlet port, and a higher pressure one of pressure oil introduced into the first inlet port and the second inlet port by moving in the valve body; And a valve body for guiding the hydraulic oil to the outlet port, and a first electrical port when the hydraulic oil pressure at the first inlet port is higher than the hydraulic oil pressure at the second inlet port by detecting the movement of the valve body. A switch signal of a second electrical state different from the first electrical state when a hydraulic signal pressure at the second inlet port is higher than a hydraulic oil pressure at the first inlet port when a switch signal for the state is generated. Switch hand It is equipped with a door.

In the hydraulic elevator system according to the present invention, when the car is raised or lowered, the control device activates the start / stop operation solenoid valve, and the pilot pressure chamber of the main check valve is provided with the downstream pressure (second pressure) of the main check valve. By introducing the next pressure, the main check valve has an optimum opening degree according to the passing flow rate.

In addition, when the car is stopped, the start / stop operation solenoid valve is driven by the high-pressure side oil guided to the outlet of the selector valve in response to the immediately preceding ascent or descent operation. If there is, the hydraulic oil on the hydraulic pump side of the main check valve, and if the previous operation is a descending operation, the hydraulic oil on the hydraulic jack side of the main check valve is introduced into the pilot pressure chamber of the main check valve, thereby performing the main check Forcibly close the valve. This valve closing operation is performed in a state in which the moving speed of the immediately preceding car, that is, the passing flow rate of the main flow path by the hydraulic pump is suppressed to a low flow rate by the variable speed control by the control device. Since the opening degree of the main check valve is also small, the passing flow rate when the valve is closed is small, and the stop shock of the car is suppressed.

The operation start timing of the start / stop operation solenoid valve at the time of starting the car is when the hydraulic jack side pressure and the hydraulic pump side pressure of the main check valve of the main flow path are substantially equal. According to the invention, this corresponds to when the selector valve derives the hydraulic pump side pressure at its outlet. That is, normally, when the car is stopped, the main check valve is closed and the hydraulic pump is stopped, so the pressure on the hydraulic jack side is higher, so the pressure on the hydraulic jack side appears at the outlet of the selector valve. ing. At the time of starting the car, first, based on the start signal from the operation panel, whether the ascending or descending, the hydraulic pump is once normally rotated in the initial operation by the control device, and the pressure on the hydraulic pump side is changed to the hydraulic jack side. Since the pressure is increased to the pressure, the hydraulic pump side pressure appears at the outlet of the selector valve when the hydraulic pump side pressure becomes slightly higher than the hydraulic jack side pressure.

According to a preferred aspect of the present invention, the operation of the selector valve, that is, the operation of the selector valve when the hydraulic pump side pressure of the main flow path becomes higher than the hydraulic jack side pressure, is set to the selector valve. The detection is performed by the provided switch means, and the electrical signal output based on the detection is used for the sequence operation of the control device in combination with the start signal, whereby the start of the start / stop operation solenoid valve is executed. Accordingly, in this case, there is no need for a plurality of hydraulic pressure detectors for detecting the pressures on the hydraulic pump side and the hydraulic jack side of the main flow path, respectively, and a complicated configuration for electronically comparing the detected pressure values as in the related art. .

[0013]

FIG. 1 is a hydraulic circuit diagram showing an example of an embodiment of a hydraulic elevator apparatus according to the present invention. The device comprises a hydraulic jack 2 for driving the car 1 up and down,
A hydraulic pump 4 driven by an inverter motor M at a forward / reverse variable speed, and an electromagnetically operated hydraulic on / off valve device 3 for controlling opening and closing of a main flow path between the hydraulic pump 4 and the hydraulic jack 2
And a controller 12 which is a control device for controlling these operations.

The electromagnetically operated hydraulic on-off valve device 3 includes a main check valve 5 for opening and closing the main flow passage, and a first pilot passage LP1 communicating with a pilot pressure chamber (spring chamber) 5a of the main check valve 5, and a second pilot passage LP2. Alternatively, there is no leakage between the solenoid valve 6 for switching to the third pilot passage LP3 for starting and stopping operation and the communication between the first pilot passage LP1 and the fourth pilot passage LP4 communicating with the hydraulic pump side of the main passage in the deenergized state. And a lowering solenoid valve 7 for communicating the pilot pressure chamber 5a to the hydraulic pump 4 of the main check valve 5 in the excited state, and a hydraulic pressure and a hydraulic pressure for the main check valve 5 on the hydraulic jack 2 side. A shuttle valve type selector valve 8 which selects the higher one of the hydraulic pressures of the pump 4 and leads out to the outlet port 8c; A pressure sensor PG for detecting the pressure value of the hydraulic pressure guided to the outlet 8c of the selector valve 8 for monitoring purposes; the outlet 8c of the selector valve 8 is connected to the second pilot passage LP2; The passage LP3 is connected to the hydraulic jack 2 side of the main check valve 5.

The selector valve 8 has a first inlet port 8a connected to the hydraulic pump side of the main flow path, a second inlet port 8b connected to the hydraulic jack side of the main flow path, and one outlet port 8c. Is provided in the valve body.
By moving in accordance with the pressure acting on the inlet port 8a or 8b, any one of the higher pressure oils introduced into the first inlet port 8a and the second inlet port 8b is supplied to the outlet port 8c. Is disposed, and when the movement of the valve body 8d is detected and the hydraulic pressure at the first inlet port 8a is higher than the hydraulic pressure at the second inlet port 8b, the first electric power is supplied. A second electrical state different from the first electrical state when a hydraulic signal pressure at the second inlet port 8b is higher than a hydraulic pressure at the first inlet port 8a when a switch signal of a desired state is generated. Is provided.

In this embodiment, when the oil pressure on the hydraulic pump 4 side becomes slightly higher than the oil pressure on the hydraulic jack 2 side, the valve 8d moves from the first inlet port 8a to the second inlet port 8a.
Since the switch 13 moves to the side b, the switch 13 detects the movement of the valve body 8d and gives the controller 12 a switch signal in the first electrical state, that is, an ON signal in this case.
A manually operated opening / closing valve 17 is connected between the hydraulic jack 2 and the tank line to be manually opened when necessary to reduce the hydraulic jack pressure to the tank line.

As the switch 13 of the selector valve 8, various configurations can be used. For example, FIGS. 2 and 3 show typical examples. In the configuration shown in FIG. 2, the valve element 8d of the selector valve 8 (in this case, a steel ball) is
A near switch 23 that generates an ON signal when moved to the side of the inlet port 8b of the selector valve 8 is used. When the valve element 8d of the selector valve 8 moves to the side of the second inlet port 8b in the configuration shown in FIG. An ON signal is obtained from the microswitch 33 by mechanically transmitting the displacement of the body 8d to the microswitch 33 via the pin 31.

The starting / stopping operation solenoid valve 6 is a double solenoid spring center three-position directional control valve having two opposed first and second solenoid devices A and B.
When the first solenoid device A is excited, it takes the ascending switching position 6a, and when the second solenoid device B is excited, it takes its descending switching position 6b. , 6e to take the neutral position for stop 6c. This solenoid valve 6
When in the ascending switching position 6a, the first pilot passage LP1 is disconnected from the second pilot passage LP2 and communicates with the third pilot passage LP3, and when in the descending switching position 6b, the first pilot passage LP1 is connected to the second pilot passage LP2. LP2 and third pilot passage L
P3, the first pilot passage LP1 is switched to the second pilot passage L when the stop neutral position 6c is reached.
Only communicate with P2.

The lowering operation solenoid valve 7 is a poppet valve type opening / closing valve provided with a solenoid device C facing the return spring 7a. When the solenoid device C is in the deenergized state, the first pilot passage LP1 and the fourth pilot passage LP are connected to each other. Pilot passage LP4
Communication with the first pilot passage LP1 when the solenoid device C is excited.
To the hydraulic pump 4 side of the main check valve 5.

The selector valve 8 has one inlet port 8b.
Receives the hydraulic pressure on the hydraulic jack 2 side of the main check valve 5 and receives the hydraulic pressure on the hydraulic pump 4 side of the main check valve 5 at the other inlet port 8a. It leads to exit 8c. A pressure sensor PG is connected to the outlet 8c of the selector valve 8, and measures the pressure of the hydraulic pressure selected by the selector valve 8.

In this apparatus, the start / stop of the car is controlled by a controller based on a command signal for opening / closing a destination floor switch of the car 1, a call switch of each floor operation panel, and a limit switch provided at each floor position of the car. Reference numeral 12 is achieved by controlling the hydraulic pump 4 in the forward / reverse variable speed by the inverter motor M and performing excitation switching control of each of the solenoid valves 6 and 7.

When the car 1 is in a stopped state, the motor M is in a stopped state and all the solenoid devices A, B,
C is also in a non-excited state. Therefore, the start / stop operation solenoid valve 6
Is in the neutral position 6c for stopping, and the lowering solenoid valve 7 is in a state of blocking the first pilot passage LP1 from the fourth pilot passage LP4.

In this state, the hydraulic jack 2 is on the high pressure side due to the load of the car 1, so that the selector valve 8 guides the hydraulic pressure on the hydraulic jack 2 side to the outlet 8c. Therefore, the hydraulic pressure on the hydraulic jack 2 side is introduced into the pilot pressure chamber 5a of the main check valve 5 through the second pilot passage LP2, the start / stop operation solenoid valve 6 (neutral position 6c), and the first pilot passage LP1. The main check valve 5 is pushed down by the hydraulic pressure to close the main flow path.

When the car 1 is started, a command signal is applied to the controller 12 from one of the switches LS provided in the car or on the operation panel of each floor. As a result, the controller 12 generates a start signal, and firstly, the oil pressure in the oil passage between the hydraulic pump 4 and the main check valve 5, that is, the pressure on the hydraulic pump 4 side of the main flow path blocked by the main check valve 5. Until the pressure reaches the pressure on the hydraulic jack 2 side, and then the inverter motor M is driven by a variable speed control signal according to an ascending or descending speed pattern by sequence control. The hydraulic pump 4 performs a forward / reverse discharge operation in accordance with the rotation of the inverter motor M. Therefore, the discharge flow rate from the hydraulic pump 4 is
It changes according to the ascending or descending speed pattern from the controller 12.

Excitation control of the solenoid devices of the solenoid valves 6 and 7 is switched by the controller 12 based on a command signal from an operation panel and a signal from the switch 13 when the car 1 is started. The switch 13 gives an ON signal to the controller 12 when the hydraulic pressure on the hydraulic pump 4 side becomes slightly higher than the hydraulic pressure on the hydraulic jack 2 side. Here, assuming that the pressure on the hydraulic pump 4 side is Pp and the pressure on the hydraulic jack 2 side is Pj, a certain dead value ΔP = Pp−Pj is given to the detection characteristic of the switch 13 in advance. When the pressure on the side becomes higher than the pressure on the hydraulic jack 2 side by ΔP, it is preferable that the switch 13 surely generates an output.

When raising the car 1, the controller 12 executes the above-described initial normal operation of the hydraulic pump 4 in response to the start signal at the same time as the arrival of the command signal. still,
At this time, the solenoid devices A, B, and C remain demagnetized. In this initial state, the main check valve 5 is not yet opened, and the pilot pressure chamber 5a of the main check valve 5 is connected to the outlet port of the selector valve 8 via the start / stop operation solenoid valve 6 in the neutral position 6c. 8
A pressure of c has been derived.

The pressure on the hydraulic pump 4 side rises due to the initial forward rotation of the hydraulic pump 4, and when it slightly exceeds the pressure on the hydraulic jack side, the valve body 8d of the selector valve 8
Moves instantaneously from the first inlet port 8a side to the second inlet port 8b side. The movement of the valve 8d is controlled by the switch 13
When the switch 13 generates an ON signal, the controller 12 excites only the solenoid device A, and simultaneously decreases the forward rotation speed of the hydraulic pump 4 by the inverter motor M, and then increases the internally set ascent. The variable speed control according to the (forward rotation) speed pattern is started.

In this state, the start / stop operation solenoid valve 6 is switched to the ascending switching position 6a, so that the first pilot passage LP1 communicating with the pilot pressure chamber 5a is provided.
Is connected to the hydraulic jack 2 side of the main flow path via the third pilot passage LP3, that is, the downstream side. Therefore, when the discharge amount from the hydraulic pump 4 increases according to the variable speed control pattern, the main check valve 5 The poppet is gradually pushed open at an opening corresponding to the pressure difference between the hydraulic pump 4 side and the hydraulic jack 2 side, whereby the car 1 starts the upward movement smoothly.

The speed of the car 1 during the ascending operation is controlled by controlling the discharge amount of the hydraulic pump 4 according to the variable speed control pattern by the inverter motor M, as is well known. The inclinations of the acceleration pattern and the deceleration pattern in the variable speed control are determined by the moving distance of the car to the target floor and the time determined by the upper limit speed. When the ascending operation is started, the inverter motor M gradually increases the number of revolutions in accordance with the acceleration pattern, whereby the discharge amount of the hydraulic pump 4 increases, and the car 1 is accelerated. When the vehicle passes an intermediate position within a predetermined distance, a position detection switch (not shown) such as a limit switch disposed at that position sends a deceleration command signal to the controller 12, and the controller 12 receives this signal and decelerates the inverter motor M. The pattern changes to a pattern, and in response to this, the hydraulic pump 4 gradually reduces the discharge amount, and the car is decelerated.

In front of the destination floor, the car 1 moves to a constant low speed in accordance with the variable speed control pattern. When the position detection switch of the destination floor detects the arrival of the car, the controller 12 issues a stop command signal to generate the inverter motor. M is further decelerated, whereby the discharge amount of the hydraulic pump 4 is reduced to stop the car 1, and the excitation of the solenoid device A is cut off after a predetermined time period from the output of the stop command signal. At this time, the opening degree of the main check valve 5 is gradually reduced in accordance with the decrease in the flow rate, and by selecting the above-mentioned speed setting at the time of constant low-speed movement optimally,
Car 1 during stop operation due to deenergization of solenoid device A
The valve closing operation can be performed without giving a shock.

That is, in this valve closing operation, the pressure introduced into the pilot pressure chamber 5a is changed from the downstream side (the hydraulic jack 2 side) to the outlet of the selector valve 8 by the return to the neutral position 6c of the start / stop operation solenoid valve 6. This is performed by switching to the pressure on the upstream side (the hydraulic pump 4 side) that appears at the port 8c. If the speed setting during the low-speed movement is properly selected, the pressure difference at the time of this switching is small. Therefore, the car 1 does not cause an excessive shock due to the closing operation of the main check valve 5.

After the car 1 stops, the pressure at the outlet port 8c of the pilot pressure chamber 5a of the main check valve 5 always acts on the pilot pressure chamber 5a via the selector valve 8, so that the solenoid valves 6, 7 are thereafter demagnetized. Controller 1 as it is
Even if the hydraulic pump 4 performs an abnormal discharge operation due to the malfunction of 2 and the hydraulic pump side pressure becomes higher than the hydraulic jack side pressure, the selector valve 8 always causes the high pressure side pressure to act on the pilot pressure chamber 5a. Therefore, there is no danger of an abnormal rise of the car.

Next, when the car 1 is driven to descend, the controller 12 generates a start signal in response to the arrival of the command signal, and first executes the initial normal rotation operation of the hydraulic pump 4 as described above. At this time, the solenoid devices A, B,
C remains in the demagnetized state. In this initial state, the main check valve 5 has not been opened yet, and the pilot pressure chamber 5a of the main check valve 5 is moved from the selector valve 8 to the hydraulic jack 2 via the start / stop operation solenoid valve 6 at the neutral position 6c. Side pressure is guided.

When the pressure on the hydraulic pump 4 side rises due to the initial forward rotation of the hydraulic pump 4 and the switch 13 generates an ON signal as described above, the controller 12 excites only the solenoid devices B and C, and After the forward rotation speed of the hydraulic pump 4 by the inverter motor M is once reduced, the variable speed control according to the internally set down (reverse rotation) speed pattern is started.

In this state, since the lowering operation solenoid valve 7 is excited, the pilot pressure chamber 5a is connected to the hydraulic pump 4 side of the main flow path, that is, the downstream side, and accordingly, according to the variable speed control pattern. As the flow rate flowing into the hydraulic pump 4 increases, the poppet of the main check valve 5 is gradually pushed open at an opening corresponding to the pressure difference between the hydraulic jack 2 and the hydraulic pump 4, thereby causing the car 1 will start the downward movement smoothly.

The speed of the car 1 during the descent operation is also controlled by controlling the discharge amount of the hydraulic pump 4 according to the variable speed control pattern by the inverter motor M in the same manner as described above. However, in this case, the hydraulic pump is operating in reverse. That is, when the descent operation is started, the inverter motor M gradually increases the reverse rotation speed according to the acceleration pattern, whereby the flow rate flowing into the hydraulic pump 4 is increased, and the car 1 is lowered and accelerated. When the vehicle passes an intermediate position of a predetermined distance to the destination floor, a position detection switch (not shown) such as a limit switch disposed at that position sends a deceleration command signal to the controller 12, and the controller 12 receives this signal. Turn the inverter motor M to the deceleration pattern,
In response, the hydraulic pump 4 gradually reduces the reverse rotation discharge amount, and the car is decelerated.

Before the destination floor, the car 1 moves to a constant low-speed movement according to the variable speed control pattern. When the position detection switch of the destination floor detects the arrival of the car, the controller 12 issues a stop command signal to generate the inverter motor M Is further reduced, thereby reducing the discharge amount of the hydraulic pump 4 to stop the car 1, while exciting the solenoid devices B and C by a predetermined timed operation from the output of the stop command signal.

At this time, the opening of the main check valve 5 is gradually reduced in accordance with the decrease in the flow rate, and the speed setting at the time of the constant low-speed movement is optimally selected so that the solenoid device B , C, the introduction pressure to the pilot pressure chamber 5a is switched from the downstream side (the hydraulic pump 4 side) to the upstream side (the hydraulic jack 2 side), so that the car 1 is closed without giving a shock. In this case, the valve closing operation is performed when the pilot pressure guided from the downstream side (the hydraulic pump 4 side) via the lowering operation solenoid valve 7 is cut off by the demagnetization of the lowering operation electromagnetic valve 7. At the same time, the neutral position 6 of the start / stop operation solenoid valve 6
The pressure guided to the second pilot passage LP2 via the selector valve 8 by the return to c causes the pressure to act on the pilot pressure chamber 5a.

Even after the descent operation is stopped, after the car 1 is stopped in the same manner as described above, the pressure of the outlet port 8c of the pilot pressure chamber 5a of the main check valve 5 is always maintained via the selector valve 8. Therefore, even if the hydraulic pump 4 performs an abnormal discharge operation due to malfunction of the controller 12 while the solenoid valves 6 and 7 are in the demagnetized state, the hydraulic pump side pressure becomes higher than the hydraulic jack side pressure. Since the pressure on the high pressure side always acts on the pilot pressure chamber 5a by the selector valve 8, there is no danger that the car will abnormally rise.

[0040]

As described above, according to the hydraulic elevator system of the present invention, the main check valve operates not only in the same manner as a normal check valve that opens and closes according to the differential pressure between the upstream side and the downstream side, but also in the car. Is stopped, the selector valve is provided so that the pressure on the high pressure side before or after the main check valve always acts on the pilot pressure chamber, so even if the hydraulic pump performs abnormal discharge operation while the car is stopped The car does not move, and the shock at the time of starting can be effectively suppressed by the function of the main check valve itself, and furthermore, an effect that an expensive hydraulic detector and an electronic device for signal processing thereof are not required can be obtained. Things.

[Brief description of the drawings]

FIG. 1 is a hydraulic circuit diagram showing one embodiment of a hydraulic elevator device according to the present invention.

FIG. 2 is a schematic structural diagram showing a specific configuration example of a selector valve.

FIG. 3 is a schematic structural view showing another specific configuration example of the selector valve.

[Explanation of symbols]

 1: Car 2: Hydraulic jack 3: Electromagnetically operated hydraulic on-off valve device 4: Hydraulic pump 5: Main check valve 5 a: Pilot pressure chamber 6: Solenoid valve for start / stop operation 6 a: Switching position for ascending 6 b: Switching position for descending 6c: Neutral position for stop 7: Solenoid valve for lowering operation 8: Selector valve 12: Controller 13: Switch A: First solenoid device B: Second solenoid device C: Solenoid device M: Inverter motor PG: Pressure sensor

Claims (3)

[Claims] 1. A hydraulic jack for driving a car up and down, an electric motor controlled by forward / reverse variable speed control, a hydraulic pump driven by the electric motor, and opening and closing of a main flow path between the hydraulic pump and the hydraulic jack. And a command signal is supplied to the electric motor and the electromagnetically operated hydraulic on / off valve device so that when the pressures on the hydraulic jack side and the hydraulic pump side become substantially equal, the electromagnetic operation is performed. A control device for controlling a hydraulic jack operating speed by controlling a supply / discharge flow rate of a hydraulic pump by forward / reverse variable speed control of the electric motor while opening the hydraulic on / off valve device, wherein the electromagnetically operated hydraulic on / off valve device Is located in the main flow path between the hydraulic pump and the hydraulic jack and opens at an opening corresponding to the flow rate when the valve is opened. A valve, a selector valve for selecting the hydraulic oil on the high pressure side of the hydraulic jack side or the hydraulic pump side of the main flow path and guiding it to its own outlet, and the control device at the time of starting and stopping the car, A start / stop operation solenoid valve to be controlled, wherein the start / stop operation solenoid valve switches the pilot pressure chamber of the main check valve to a main flow path downstream of the main check valve when the car starts. Takes a switching position when the car stops, introducing pressure oil guided to the outlet of the selector valve into the pilot pressure chamber of the main check valve to forcibly close the main check valve. A hydraulic elevator device characterized by the following. 2. The switch according to claim 1, wherein the selector valve includes a switch for generating an electric signal output when the hydraulic pump side pressure of the main flow path becomes higher than the hydraulic jack side pressure. A hydraulic elevator device as described. 3. A valve body having first and second two inlet ports and one outlet port, and introduced into the first inlet port and the second inlet port by moving within the valve body. A valve body for guiding any one of the higher pressure oils to the outlet port, and a pressure of the first inlet port being higher than a pressure oil pressure of the second inlet port by detecting the movement of the valve body. When the hydraulic pressure is higher, a switch signal of the first electrical state is generated, and when the hydraulic pressure of the second inlet port is higher than the hydraulic pressure of the first inlet port, the first electrical state is switched. Switch means for generating a switch signal of a different second electrical state.