JPH0753161A - Hydraulic elevator controller - Google Patents

Abstract

(57) [Summary] [Purpose] To reduce the pressure loss of the on-off valve during the ascending operation of the hydraulic elevator so that the car can be stopped for a short distance even if a power failure occurs during the descending operation. [Constitution] When the car (2) rises, close the first on-off valve (5),
The second on-off valve (21) is opened, the pressure oil discharged from the hydraulic pump (3) is sent to the hydraulic jack (1), and the car (2) is raised. The second on-off valve (21) is closed when descending, and the first on-off valve (5)
Is opened to discharge the pressure oil of the hydraulic jack (1) to the oil tank (8) by controlling the hydraulic pump (3). Since the first on-off valve (5) is exclusively for lowering, the opening can be set small regardless of the ascending operation. Since the valve body (21b) of the second opening / closing valve (21) has an opening degree corresponding to the flow rate of the pressure oil, the valve body (21b) is promptly closed when the flow of the pressure oil is stopped due to a power failure.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for controlling a hydraulic elevator by changing the rotation speed of a hydraulic pump.

[0002]

2. Description of the Prior Art FIG.
FIG. 6 is a hydraulic circuit diagram showing a control device for a conventional hydraulic elevator described in Japanese Patent Publication. In the figure, (1) is a hydraulic jack, (2) is a basket supported by the hydraulic jack (1), (3) is a reversibly rotatable hydraulic pump, (4) is an electric motor for driving the hydraulic pump (3), (5) is the main chamber (5a) and the main chamber through the valve body (5b)
An on-off valve having (5a) and an isolated back chamber (5c).

(6) is the main chamber (5) of the hydraulic pump (3) and the on-off valve (5)
The first circuit (6a) connecting with a) and the main chamber (5a) of the on-off valve (5)
The first main circuit (7) consisting of the second circuit (6b) for connecting the hydraulic pump (1) and the hydraulic jack (1) is provided in the oil tank (8), and the hydraulic pump
A filter connected to (3), (9) a pressure oil inflow circuit (9a) connecting the hydraulic jack (1) and the back chamber (5c) of the on-off valve (5),
A pilot circuit consisting of a pressure oil discharge circuit (9b) connecting the back chamber (5c) of the on-off valve (5) and the oil tank (8), and (10) a pressure oil inflow circuit
The normally open solenoid valve inserted in (9a) and (11) the normally closed solenoid valve inserted in the pressure oil discharge circuit (9b).

Reference numeral (12) is a variable throttle valve provided in the pressure oil inflow circuit (9a), (13) is a variable throttle valve provided in the pressure oil discharge circuit (9b), and (14) is a solenoid valve (10). (11) and a control device for controlling the electric motor (4), (15) holds the valve body (5b) at a predetermined opening between the fully opening and closing of the opening / closing valve (5) during deceleration traveling in descending operation. An opening adjustment diaphragm for adjusting the aperture, (15a) is a variable diaphragm that opens to the outside (15b)
An adjusting screw (15c) for adjusting the opening degree of is a sleeve fixed to the valve body (5b) and forming an opening degree of the variable throttle (15b) between the variable throttles (15b).

(16) is a variable throttle (15b) of the on-off valve (5) and an oil tank
(8) is connected to the pressure oil discharge circuit, (17) is the pressure oil discharge circuit (1
Normally closed solenoid valve inserted in 6), (18) pressure oil discharge circuit
The variable throttle valve provided in (16).

The conventional hydraulic elevator control device is constructed as described above and operates as follows. First, when an ascending operation command is issued, the electric motor (4) is operated by the control device (14). After that, the solenoid valve (10) is energized and the pressure oil inflow circuit
(9a) is closed, and then the solenoid valve (11) is energized to open the pressure oil discharge circuit (9b). As a result, the back chamber of the on-off valve (5)
The pressure oil of (5c) is discharged to the oil tank (8), the valve body (5b) moves upward in the figure, and the opening / closing valve (5) opens.

When the opening / closing valve (5) is opened, the pressure oil discharged from the hydraulic pump (3) contains the first circuit (6a) → the opening / closing valve (5) → the second circuit.
As it flows into the hydraulic jack (1) through the circuit (6b), the car (2) rises. After that, the control device (14) controls the rotation speed of the electric motor (4) and the rising speed of the car (2) according to a predetermined operation pattern.

When the car (2) arrives at the predetermined floor, the car
(2) stops. Then, the control device (14) controls the opening / closing valve (5).
When the closing command is issued, the solenoid valve (11) is deenergized, the pressure oil discharge circuit (9b) is closed, the solenoid valve (10) is deenergized, and the pressure oil inflow circuit (9a) is opened. With this, the valve body (5b) moves downward in the figure, and the on-off valve (5) is fully closed.

Next, when a descending operation command is issued, the control device (1
4) energizes the solenoid valve (10), closes the pressure oil inflow circuit (9a), then energizes the solenoid valve (11), and pressurizes the oil discharge circuit (9b).
Opens. With this, the pressure oil in the back chamber (5c) of the on-off valve (5) is discharged to the oil tank (8), the valve body (5b) moves upward in the figure, and the on-off valve (5) opens.

When the on-off valve (5) opens, the hydraulic jack (1)
The pressure oil inside is squeezed out by the weight of the car (2), and the hydraulic jack (1) → second circuit (6b) → open / close valve (5) → first circuit (6a) →
The oil is discharged to the oil tank (8) through the hydraulic pump (3) → the filter (7). After that, the hydraulic pump (3) driven by the electric motor (4) by the control device (14) discharges the pressure oil in the hydraulic jack (1), so that the car (2) descends. In order to drive the hydraulic pump (3) with the pressure in the hydraulic jack (1) generated by the weight of the car (2) and the flow rate discharged from the hydraulic jack (1),
The electric motor (4) is operated by dynamic braking.

Therefore, by controlling the rotation speed of the electric motor (4) by the control device (14), the descending speed of the car (2) is controlled in accordance with a predetermined operation pattern. Basket
When (2) reaches the predetermined floor, the car (2) stops. When the control device (14) issues a closing command for the on-off valve (5), the solenoid valve (11) is deenergized, the pressure oil discharge circuit (9b) is closed, and the solenoid valve (10) is deenergized. The pressure oil inflow circuit (9a) opens. Now, the valve body (5b) moves downward in the figure, and the on-off valve (5)
Closes completely.

[0012]

In the conventional hydraulic elevator control device as described above, since the on-off valve (5) is opened during the ascending and descending operation, the power supply is cut off during operation and the electric motor (4 ) Is stopped, the oil tank (8) passes from the hydraulic jack (1) through the open / close valve (5) until the open / close valve (5) is fully closed.
The pressure oil flows out. Therefore, the car (2) descends. In order to suppress the descending speed of the car (2), it is necessary to fix the opening degree of the on-off valve (5) small.

For this reason, the hydraulic pump is used when traveling upward.
The pressure loss when the pressure oil discharged from (3) passes through the on-off valve (5) becomes large, and the discharge pressure of the hydraulic pump (3) must be increased, and along with this, the electric motor (4) Has to be increased, which results in an increase in power consumption.

Further, in the hydraulic elevator, the car (2) may be moved from an arbitrary position to an arbitrary position by low-speed descending traveling during installation or maintenance work. At this time, the on-off valve
Open (5), regeneratively brake the electric motor (4) and hydraulic pump (3)
The speed of discharge of the pressure oil in the hydraulic jack (1) may be controlled by changing the rotation speed of the. In this case, the regenerative braking of the electric motor (4) will be disabled when the power is cut off.
The car (2) accelerates and descends until the on-off valve (5) starts to close, and then the on-off valve (5) is fully closed to stop.

Therefore, when the power is cut off, the car
(2) has a problem that it is dangerous because the distance traveled down until it stops is long.

The present invention has been made to solve the above-mentioned problems, and it is possible to reduce the pressure loss of the on-off valve during the ascending operation and to stop the car at a short distance even when the power supply is cut off during the descending operation. An object of the present invention is to provide a control device for such a hydraulic elevator.

[0017]

A control device for a hydraulic elevator according to a first aspect of the present invention is provided between a hydraulic jack and a hydraulic pump, and is a first opening / closing device that opens when a car descends and closes when a car stops. A valve and a second opening / closing valve that opens when the car rises and closes when the car stops are provided.

Further, a control device for a hydraulic elevator according to a second aspect of the present invention connects the first opening / closing valve of the first aspect of the invention with the opening between the hydraulic pump and the hydraulic jack at an opening corresponding to the flow rate of the pressure oil when the car is rising. The second on-off valve that has a piston that operates by engaging the valve element communicating with the above-mentioned valve element when the car descends at a low speed, and the hydraulic pressure of the second on-off valve at an opening degree that corresponds to the flow rate of pressure oil when the car descends at a low speed. The third opening / closing valve having a valve body that communicates between the pump side and the oil tank is provided.

Also, a control device for a hydraulic elevator according to a third aspect of the present invention communicates between the first opening / closing valve of the first aspect of the invention and the hydraulic pump and the hydraulic jack when the car is moving up and down and when the car is stopped. Connect the second on-off valve that closes, the third on-off valve that communicates between the hydraulic pump side of the second on-off valve and the oil tank when the car descends at low speed, and the back chamber of the third on-off valve when the car descends at low speed to the oil tank And a solenoid valve.

Also, a control device for a hydraulic elevator according to a fourth aspect of the present invention is a first on-off valve of the first aspect of the invention, second and third on-off valves of the third aspect of the invention, a hydraulic pump and second and third aspects. The check valve is provided between the hydraulic pump and the third open / close valve and permits the flow of the pressure oil only from the hydraulic pump to the second and third open / close valves.

Further, a control device for a hydraulic elevator according to a fifth aspect of the present invention is the first on-off valve of the first aspect of the invention, the second and third on-off valves of the third aspect of the invention, and the second low speed descending car. A solenoid valve that connects the back chamber of the on-off valve to the oil tank is provided.

The control device for the hydraulic elevator according to the sixth aspect of the present invention communicates between the hydraulic pump and the hydraulic jack when the car is moving up and down, and the second opening / closing valve that is closed when the car is stopped and the car is moving down. And a third opening / closing valve that connects the hydraulic pump side of the second opening / closing valve and the oil tank.

The control device for a hydraulic elevator according to a seventh aspect of the invention is the control device for a hydraulic elevator according to the sixth aspect of the invention, wherein the second solenoid valve connects the back chamber of the second on-off valve to the oil tank when a descent start command is input. And a third solenoid valve that connects the back chamber of the third opening / closing valve to the oil tank when a descent start command is input, and a third descent when the car descends.
And a controller for giving the above-mentioned descent start command to the solenoid valve and, after a predetermined time, giving the descent command to the second solenoid valve.

The control device for a hydraulic elevator according to an eighth aspect of the present invention is the control device for a hydraulic elevator according to the sixth aspect, wherein the second solenoid valve connects the back chamber of the second opening / closing valve to the oil tank when a descending stop command is input. And a third solenoid valve that connects the back chamber of the third opening / closing valve to the oil tank when a descent stop command is input, and a second descent when the car descends.
And a controller for giving a descending stop command to the solenoid valve and, after a predetermined time, issuing a descending stop command to the third solenoid valve.

[0025]

In the first aspect of the present invention, the first opening / closing valve is opened when the car is descending, and the second opening / closing valve is opened when the car is raised. The pressure oil discharged from the pump does not pass through the first opening / closing valve.

Further, in the second aspect of the invention, the second on-off valve is a piston which operates by engaging the valve body having an opening corresponding to the flow rate of the pressure oil when the car rises and the valve body when the car descends at a low speed. The third opening / closing valve is configured to communicate between the hydraulic pump side of the second opening / closing valve and the oil tank at an opening degree corresponding to the flow rate of the pressure oil when the car descends at a low speed. Even if the middle power supply is cut off, the second and third opening / closing valves are quickly closed according to the flow rate.

Further, in the third invention, since the back chamber of the third opening / closing valve is connected to the oil tank when the car descends at a low speed, the third opening / closing valve is connected to the oil tank from the hydraulic jack via the second opening / closing valve. Open the flow path to.

Further, in the fourth aspect of the invention, since the check valve is provided between the hydraulic pump and the second and third opening / closing valves, the pressure oil from the hydraulic jack does not flow into the hydraulic pump during the low speed descent. , All pass through the third on-off valve and flow out to the oil tank.

In the fifth aspect of the invention, since the back chamber of the second opening / closing valve is connected to the oil tank when the car descends at a low speed, the second opening / closing valve passes from the hydraulic jack to the third opening / closing valve. Open the flow path to the oil tank.

Further, in the sixth aspect of the invention, since the flow path from the hydraulic jack to the oil tank is formed through the second and third opening / closing valves, the car descends by its own weight when the car descends at a low speed.

Further, in the seventh invention, when the car descent start command is input, the third solenoid valve connecting the back chamber of the third opening / closing valve to the oil tank is operated, and after a predetermined time, the second opening / closing valve. Since the second solenoid valve connecting the back chamber to the oil tank is operated, even if the operation of the third solenoid valve is delayed, the flow rate of the pressure oil during the low speed descent depends on the opening area of the second opening / closing valve.

Further, in the eighth aspect of the invention, when the car descent stop command is input, the operation of the second electromagnetic valve that connects the back chamber of the second opening / closing valve to the oil tank is stopped, and after a predetermined time, the third electromagnetic valve is stopped.
Since the operation of the third solenoid valve that connects the back chamber of the on-off valve to the oil tank is stopped, even if the operation of the second solenoid valve is delayed,
The flow rate of the pressure oil when descending at a low speed depends on the opening area of the second opening / closing valve.

[0033]

1 and 2 are views showing an embodiment of the first to eighth inventions of the present invention. FIG. 1 is a hydraulic circuit diagram and FIG. 2 is a second embodiment.
FIG. 7 is an operation explanatory diagram of the third on-off valve, and the same parts as those of the conventional device are denoted by the same reference numerals.

In FIG. 1, (21) is the second opening / closing valve, which is the main chamber.
(21a), valve body (21b), back chamber (21c), compression spring (21d), piston (21e) and back chamber (21f), and the piston (21e) moves upward in the figure, the valve body ( The compression spring (21d) is provided between the piston (21e) and the valve body (21b) and presses both (21d) and (21e) against each other. (twenty one
g) is a stopper that regulates the lowered position of the piston (21e).

Reference numeral (22) is a second main circuit which connects the hydraulic pump (3), the second opening / closing valve (21) and the hydraulic jack (1) in this order. The second main circuit includes the hydraulic pump (3) and the second opening / closing valve (21). The first circuit (22a) connecting the main chamber (21a), the main chamber (21a) of the second opening / closing valve (21) and the first opening / closing valve
The second circuit (22b) connects the main chamber (5a) of (5). Reference numeral (23) is a check valve which is inserted into the first circuit (22a) and permits the flow of pressure oil only from the hydraulic pump (3) to the second opening / closing valve (21).

Reference numeral (24) is a pilot circuit connected to the hydraulic jack (1). The pilot circuit (24a) connects the pilot circuit (24) and the back chamber (21f) of the second opening / closing valve (21), and the pilot circuit. It has a pilot circuit (24b) that connects the circuit (24) and the third main circuit (30) (described later). (26) is the pilot circuit
Variable throttle valve provided in (24), (27) is pilot circuit (2
A normally closed solenoid valve inserted in 4b), and (28) is a variable throttle valve provided in the pilot circuit (24b).

Reference numeral (29) is a third opening / closing valve, which includes a main chamber (29a) and a valve body (29).
b), the back chamber (29c) and the compression spring (29d).
In d), the valve element (29b) is always pressed in the closing direction. (3
Reference numeral 0) is a third main circuit in which a hydraulic pump (3), a third opening / closing valve (29) and an oil tank (8) are connected in order, and the first circuit (22a) of the second main circuit and the third opening / closing valve (29). And a second circuit (30b) connecting the oil tank (8) and the main chamber (29a) of the third opening / closing valve (29).

(31) is a pilot circuit connecting the first circuit (30a) and the back chamber (29c) of the third on-off valve (29), (32) is a variable throttle valve provided in the pilot circuit (31), (33) is the third on-off valve
Pilot circuit connecting the back chamber (29c) of (29) and the oil tank (8),
(34) is a normally closed solenoid valve inserted in the pilot circuit (33).

Next, the operation of this embodiment will be described. 1. Ascending operation When an ascending operation command is issued, the motor (4) is controlled by the controller (14).
Is activated and its rotation speed is controlled. As a result, the hydraulic pump (3) is driven and the hydraulic pressure of the first circuit (22a) of the second main circuit rises. When the pressure of the first circuit (22a) of the second main circuit overcomes the pressure of the second circuit (22b) and the force of the compression spring (21d), the valve body (21b) moves and the second opening / closing is performed. The valve (21) opens and pressure oil flows from the second circuit (22b) to the main chamber (5) of the first on-off valve (5).
a) and the hydraulic jack via the second circuit (6b) of the first main circuit
It flows into (1).

The car (2) now starts to rise and the motor
The car (2) accelerates as the rotation speed of (4) increases, and the opening degree of the valve body (21b) increases as the flow rate of the second opening / closing valve (21) passes through the main chamber (21a). It will become. When the speed of the car (2) reaches the rated speed, the rotation speed of the electric motor (4) becomes constant and the flow rate discharged from the hydraulic pump (3) also becomes constant.
At this time, the solenoid valve (27) is deenergized, and the pilot circuit (24b) is closed. Therefore, since the hydraulic pressure of the hydraulic jack (1) is applied to the back chamber (21f) through the pilot circuit (24a), the piston (21e) is pressed by the stopper (21g).

Further, when the car (2) runs upward and a deceleration command is issued before the predetermined distance on the floor to be stopped, the rotation speed of the electric motor (4) decreases, and accordingly the car (2) decelerates, When the opening of the valve disc (21b) becomes smaller with the flow rate passing through the main chamber (21a) and the car (2) arrives at the landing position on the scheduled stop floor, the valve disc (21b) is fully closed. After that, the electric motor (4) is stopped.

2. Down operation When a down operation command is issued, the controller (14) controls the motor (4).
The rotational speed of is controlled and driven. As a result, the hydraulic pump (3) is driven and the pressure in the first circuit (6a) of the first main circuit rises. When the detection device (not shown) detects that this pressure is almost the same as the pressure of the second circuit (6b) of the first main circuit, the control device (14) causes the solenoid valve (11) to operate. It is energized and the pressure oil discharge circuit (9b) opens.

With this, the pressure oil in the back chamber (5c) of the first opening / closing valve (5) is discharged to the oil tank (8), the valve body (5b) moves, and the first opening / closing valve (5) moves.
(5) opens. When the first opening / closing valve (5) starts opening, the pressure oil in the hydraulic jack (1) is squeezed out by the weight of the car (2), and the hydraulic jack (1) → first opening / closing valve (5) → Hydraulic pump
(3) → It is discharged to the oil tank (8) through the filter (7). At this time, the hydraulic pump (3) driven by the electric motor (4) by the control device (14) discharges the pressure oil in the hydraulic jack (1).

Since the hydraulic pump (3) is driven by the pressure in the hydraulic jack (1) generated by the own weight of the car (2) and the flow rate discharged from the hydraulic jack (1), the electric motor (4) brakes by power generation. Be driven. Therefore, the control device (14)
By controlling the rotation speed of (4), the car (2) descends according to a predetermined operation pattern.

When an acceleration traveling command for descending operation is issued to the car (2), the solenoid valve (11) is energized by the control device (14) and the pressure oil discharge circuit (9b) is opened. As a result, the opening of the first opening / closing valve (5) is gradually increased by changing the opening of the variable throttle valve (13) as the speed increases during acceleration traveling. 1. The time from when the on-off valve (5) is fully closed to when it is fully opened can be adjusted.

When the controller (14) issues a closing command for the first on-off valve (5) at a predetermined distance before the planned stop floor by decelerating in the descending operation, the solenoid valve (11) is deenergized. , The pressure oil discharge circuit (9b) is closed. At the same time, the solenoid valve (17) is energized.
At this time, since the variable throttle (15b) of the opening adjustment throttle (15) is fully closed, the pressure oil discharge circuit (16) is not in communication.

Thus, if the opening of the variable throttle valve (12) is changed so that the opening of the first on-off valve (5) is gradually decreased as the speed decreases during deceleration traveling, First on-off valve
(5) The closing time can be adjusted. First on-off valve
As the opening of (5) gradually decreases, the opening adjustment throttle (1
The sleeve (15c) of 5) follows and moves, the variable throttle (15b) gradually opens, and the pressure oil discharge circuit (16) opens. When the opening amount of the variable throttle (15b) is such that the inflow amount of the pressure oil from the pressure oil inflow circuit (9a) matches the discharge amount of the pressure oil from the pressure oil discharge circuit (16), The on-off valve (5) stops at a partial opening.

Thereafter, when the solenoid valve (17) is deenergized, the pressure oil discharge circuit (16) is closed and the pressure oil is no longer discharged. Therefore, the pressure oil from the pressure oil inflow circuit (9a) is discharged to the first position. It flows into the back chamber (5c) of the first on-off valve (5), and the first on-off valve (5) is gradually closed and then fully closed.

3. Low speed descent operation When a low speed descent operation command is issued (during installation, maintenance work, etc.), the solenoid valve (34) for controlling the third opening / closing valve (29) is energized by the control device (14). As a result, the pilot circuit (33) is opened, and the pressure oil is discharged from the back chamber (29c) of the third opening / closing valve (29) to the oil tank (8). The valve body (29b) of the third opening / closing valve (29) is a compression spring.
Since it is pressed by (29d), the third on-off valve (29) does not open only by energizing the solenoid valve (34).

As shown in FIG. 2, at time t ₁ , the solenoid valve (34)
Is energized, the solenoid valve (27) for controlling the second on-off valve (21) is energized at time t ₂ after the time T ₁ when the passage of the solenoid valve (34) is completely opened. . Now the pilot circuit
(24a) and (24b) are opened, and the pressure oil is discharged from the back chamber (21c) of the second opening / closing valve (21) to the third main circuit (30). Due to the discharge of the pressure oil, the piston (21e) moves away from the stopper (21g), so that the piston (21e) and the valve body (21b) are engaged with each other to move integrally.

Now, the pressure oil of the hydraulic jack (1) is supplied to the hydraulic jack (1) → the first opening / closing valve (5) → the first circuit (2) of the second main circuit.
2b) → second on-off valve (21) → first circuit (30a) of third main circuit → third on-off valve (29). As a result, the third on-off valve (2
The valve body (29b) of 9) is pushed by the pressure and overcomes the force of the compression spring (29d) to move, the third on-off valve (29) is opened, and the pressure oil is the third.
It is discharged from the second circuit (30b) of the main circuit to the oil tank (8).

At this time, the opening area of the third on-off valve (29) corresponds to the passing flow rate. Therefore, the acceleration time can be adjusted by adjusting the opening area of the throttle valve (28).
By gradually opening the second opening / closing valve (21), the flow rate from the hydraulic jack (1) through the second opening / closing valve (21) to the third main circuit (30) increases, and the car (2) becomes Accelerate.

Next, when a low speed descent stop command is issued at time t ₃ , the solenoid valve (27) is deenergized and the back chamber (21) of the second opening / closing valve (21) is
The discharge of pressure oil from c) to the third main circuit (30) is stopped. Therefore, pressure oil flows from the hydraulic jack (1) through the pilot circuit (24a) into the back chamber (21c), so that the piston (21e) and the valve body (21b) move integrally and the second main circuit. Gradually close the passage in the direction of (22). Therefore, the third main circuit passes from the hydraulic jack (1) through the second on-off valve (21).
The flow rate to (30) decreases and the car (2) runs at a reduced speed.
The stop time can be adjusted by adjusting the opening area of the throttle valve (26).

The opening area of the third on-off valve (29) corresponds to the flow rate passing through, but the car (2) stops at time t ₄ , and the hydraulic jack (1) to the third main circuit (30 ), There is a slight delay time T ₃ until the valve is fully closed even if the flow rate to () disappears.
Therefore, the third on-off valve (29) is just in time to a fully closed, for example, an electromagnetic valve (27) times from the time t ₃ when being de-energized is T ₂
The solenoid valve (34) is deactivated later. Due to the force of the compression spring (29d) that constantly presses the valve body (29b) in the closing direction, the back chamber
(29c) has both oil that flows in from the oil tank (8) through the pilot circuit (33) and oil that flows in through the pilot circuit (31), so after the second on-off valve (21) is fully closed, It is possible to shorten the time T ₃ until the 3 on-off valve (29) is fully closed.

As shown in FIG. 2, after the time T ₁ when the passage of the solenoid valve (34) is completely opened, a time difference is provided so as to energize the solenoid valve (27). ) Is opened, but even if the opening of the solenoid valve (34) is delayed due to electrical or mechanical factors, it is possible to perform acceleration operation control of low-speed traveling depending on the opening area of the second opening / closing valve (21). Become. what if,
Assuming that the second opening / closing valve (21) is opened first and the third opening / closing valve (29) is opened later, the acceleration traveling of the car (2) is the third.
Since it follows the opening of the on-off valve (29), it becomes impossible to control the opening of the throttle valve (28).

As described above, the solenoid valve (34) is deenergized after a time T ₂ from when the solenoid valve (27) is deenergized, so that the opening area of the second opening / closing valve (21) is dependent on the opening area. It is possible to control acceleration operation at low speed. Assuming that the third on-off valve (29) is closed first, the pressure around the second on-off valve (21), that is, the back chamber (21f), the main chamber (21a), and the second main circuit. First
Since the pressures of the circuits (22a) are all the same, the second opening / closing valve (21) cannot be closed and stops in the state of being opened.

When a low speed descending operation is performed next from this state,
As soon as the third opening / closing valve (29) is opened, the pressure oil circulates and the car (2) descends, resulting in poor riding comfort.

Also, during low speed descent operation, the hydraulic jack (1)
The pressure oil that flows from the through the second opening / closing valve (21) to the third main circuit (30) does not flow into the hydraulic pump (3) because of the check valve (23), and is not included in the third opening / closing valve (29). To flow to the oil tank (8). If it flows into the hydraulic pump (3), its flow rate will change due to variations in the mechanical loss of the hydraulic pump (3), the viscosity pressure of the pressure oil, and the like. The check valve (23) prevents this, and eliminates the speed change during the low speed descent operation due to the influence of the hydraulic pump (3).

[0059]

As described above, according to the first aspect of the present invention, the first opening / closing valve is opened when the car is descending and the second opening valve is opened when the car is rising.
Since the on-off valve is opened, the first on-off valve is exclusively for lowering, the pressure oil discharged from the hydraulic pump does not pass through the first on-off valve when rising, and the car descends when the power is shut off. There is an effect that the fully-opened opening degree of the first on-off valve for limiting the operating speed can be reduced without pressure loss.

According to the second aspect of the invention, the second on-off valve includes a valve body having an opening corresponding to the flow rate of the pressure oil when the car is rising, and a piston which operates by engaging with the valve body when the car is descending at a low speed. In the third aspect of the invention, the third on-off valve is configured to communicate between the hydraulic pump side of the second on-off valve and the oil tank at an opening degree corresponding to the flow rate of the pressure oil during low speed descent of the car. Since the back chamber of the third opening / closing valve is connected to the oil tank when the car descends at a low speed, and the back chamber of the second opening / closing valve is also connected to the oil tank in the fifth aspect of the invention, the power supply while the car is moving up and down Even if is shut off, the second and third on-off valves can be quickly closed according to the flow rate, and the car can be stopped at a short distance.

In the fourth invention, the hydraulic pump and the second
Also, since the check valve is provided between the third opening / closing valve and the third opening / closing valve, the pressure oil from the hydraulic jack does not flow into the hydraulic pump during the low speed descent,
Even if it passes through the third opening / closing valve and flows out to the oil tank, it is not affected by variations in the mechanical loss of the hydraulic pump, the viscosity pressure of the pressure oil, and the like, and it is possible to prevent a speed change during low speed descent.

Further, in the sixth aspect of the invention, since the flow path from the hydraulic jack to the oil tank is formed through the second and third opening / closing valves, the car descends by its own weight when the car descends at a low speed,
Even if the power is cut off, the car will not accelerate and will have the effect of ensuring safety by stopping at a short descent distance.

Further, in the seventh invention, when the car descent start command is input, the third solenoid valve connecting the back chamber of the third opening / closing valve to the oil tank is operated, and after a predetermined time, the second opening / closing valve is opened. Since the second solenoid valve that connects the back chamber to the oil tank is operated, even if the operation of the third solenoid valve is delayed, the flow rate of the pressure oil during low speed descent depends on the opening area of the second opening / closing valve, This has the effect of accurately controlling the acceleration operation when descending at a low speed.

Further, in the eighth aspect of the invention, when the car descent stop command is input, the operation of the second electromagnetic valve that connects the back chamber of the second opening / closing valve to the oil tank is stopped, and after a predetermined time, the third opening / closing operation is performed. Since the operation of the third solenoid valve that connects the back chamber of the valve to the oil tank is stopped, even if the operation of the second solenoid valve is delayed, the flow rate of the pressure oil during low speed descent is the opening area of the second opening / closing valve. There is an effect that the deceleration operation during low speed descent can be accurately controlled.

[Brief description of drawings]

FIG. 1 is a hydraulic circuit diagram showing an embodiment of first to eighth inventions of the present invention.

2 is an operation explanatory view of a second on-off valve and a third on-off valve of FIG. 1. FIG.

FIG. 3 is a hydraulic circuit diagram showing a conventional hydraulic elevator control device.

[Explanation of symbols]

 1 hydraulic jack 2 basket 3 hydraulic pump 4 electric motor 5 first opening / closing valve 5a valve body 6 first main circuit 8 oil tank 14 control device 21 second opening / closing valve 21b valve body 21e piston 21f back chamber 22 second main circuit 23 check valve 27 2nd solenoid valve 29 3rd opening / closing valve 29b Valve body 29c Back chamber 30 3rd main circuit 34 3rd solenoid valve

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[Procedure amendment]

[Submission date] October 18, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0031

[Correction method] Change

[Correction content]

Further, in the seventh invention, when the car descent start command is input, the third solenoid valve connecting the back chamber of the third opening / closing valve to the oil tank is operated, and after a predetermined time, the second opening / closing valve. due to the back chamber so as to operate the second solenoid valve to be connected to the oil bath, the flow rate of the pressure oil at low speed lowering is dependent on the opening area of the second on-off valve.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Name of item to be corrected] 0032

[Correction method] Change

[Correction content]

Further, in the eighth aspect of the invention, when the car descent stop command is input, the operation of the second electromagnetic valve that connects the back chamber of the second opening / closing valve to the oil tank is stopped, and after a predetermined time, the third electromagnetic valve is stopped.
Since the back chamber of the on-off valve and to stop the operation of the third solenoid valve to be connected to the oil tank, flow rate of the hydraulic fluid in the low speed lowering is dependent on the opening area of the second on-off valve.

Claims (8)

[Claims] 1. An electric motor drives an oil tank to supply pressure oil to a hydraulic jack, and the rotation speed of the electric motor is controlled to change the discharge flow rate of a hydraulic pump to raise a car.
In an elevator that discharges the pressure oil in the hydraulic jack to an oil tank and controls the rotation speed of the electric motor to change the discharge flow rate of the pressure oil to lower the car, the elevator is provided between the hydraulic jack and the hydraulic pump. A control device for a hydraulic elevator, comprising: a first opening / closing valve that opens when the car descends and closes when stopped; and a second opening valve that opens when the car rises and closes when stopped. 2. An electric motor drives an oil tank to supply pressure oil to a hydraulic jack, the rotation speed of the electric motor is controlled to change a discharge flow rate of a hydraulic pump, and a car is raised.
In an elevator that discharges the pressure oil in the hydraulic jack to an oil tank and controls the rotation speed of the electric motor to change the discharge flow rate of the pressure oil to lower the car, the elevator is provided between the hydraulic jack and the hydraulic pump. A first on-off valve that opens when the car descends and closes when the car stops, and a valve body that communicates between the hydraulic pump and the hydraulic jack at an opening that corresponds to the flow rate of the pressure oil when the car rises, and the low speed of the car. A second opening / closing valve having a piston that operates by engaging with the valve body when descending;
A hydraulic pressure characterized by comprising a third opening / closing valve having a valve body communicating between the oil pump and the hydraulic pump side of the second opening / closing valve at an opening degree corresponding to the flow rate of the pressure oil when the car descends at a low speed. Elevator control device. 3. An electric motor drives an oil tank to supply pressure oil to a hydraulic jack, and the rotation speed of the electric motor is controlled to change the discharge flow rate of the hydraulic pump to raise the car.
In an elevator that discharges the pressure oil in the hydraulic jack to an oil tank and controls the rotation speed of the electric motor to change the discharge flow rate of the pressure oil to lower the car, the elevator is provided between the hydraulic jack and the hydraulic pump. A first on-off valve that opens when the car descends and closes when it rises and stops, and a second on-off valve that communicates between the hydraulic pump and the hydraulic jack when the car rises and descends and that closes when the car stops And the second opening at an opening corresponding to the flow rate of pressure oil when the car descends at a low speed.
A third opening / closing valve having a valve body communicating between the hydraulic pump side of the opening / closing valve and the oil tank, and a solenoid valve connecting the back chamber of the third opening / closing valve to the oil tank when the car descends at a low speed A control device for a hydraulic elevator. 4. An electric motor drives an oil tank to supply pressure oil to a hydraulic jack, and the rotation speed of the electric motor is controlled to change the discharge flow rate of the hydraulic pump to raise the car.
In an elevator that discharges the pressure oil in the hydraulic jack to an oil tank and controls the rotation speed of the electric motor to change the discharge flow rate of the pressure oil to lower the car, the elevator is provided between the hydraulic jack and the hydraulic pump. A first on-off valve that opens when the car descends and closes when it rises and stops, and a second on-off valve that communicates between the hydraulic pump and the hydraulic jack when the car rises and descends and that closes when the car stops And a third opening / closing valve communicating between the hydraulic pump side of the second opening / closing valve and the oil tank when the car descends at a low speed, and the hydraulic pressure provided between the hydraulic pump and the second and third opening / closing valves. A control device for a hydraulic elevator, comprising: a check valve that allows the pressure oil to flow only from the pump to the second and third opening / closing valves. 5. An electric motor drives an oil tank to supply pressure oil to a hydraulic jack, and the rotation speed of the electric motor is controlled to change the discharge flow rate of the hydraulic pump to raise the car.
In an elevator that discharges the pressure oil in the hydraulic jack to an oil tank and controls the rotation speed of the electric motor to change the discharge flow rate of the pressure oil to lower the car, the elevator is provided between the hydraulic jack and the hydraulic pump. A first on-off valve that opens when the car descends and closes when the car rises and stops; a second on-off valve that communicates between the hydraulic pump and the hydraulic jack when the car rises and that closes when the car stops; A third opening / closing valve that connects the hydraulic pump side of the second opening / closing valve to the oil tank when the car descends at a low speed, and a solenoid valve that connects the back chamber of the second opening / closing valve to the oil tank when the car descends at a low speed. A control device for a hydraulic elevator, comprising: 6. An elevator for supplying pressure oil to a hydraulic jack to raise a car supported by the hydraulic jack, discharging the pressure oil in the hydraulic jack to an oil tank, and lowering the car. A second on-off valve that communicates between the hydraulic pump and the hydraulic jack when ascending and descending and that closes when the car is stopped, and a fluid that connects between the hydraulic pump side of the second on-off valve and the oil tank when the car descends A control device for a hydraulic elevator, comprising: 3 open / close valves. 7. An elevator in which pressure oil is supplied to a hydraulic jack to raise a car supported by the hydraulic jack, and the pressure oil in the hydraulic jack is discharged to an oil tank to lower the car. A second on-off valve that communicates between the hydraulic pump and the hydraulic jack when rising and slowing down, and a second solenoid valve that connects a back chamber of the second on-off valve to the oil tank when a descent start command is input. A third on-off valve that connects the hydraulic pump side of the second on-off valve with the oil tank,
When the descending start command is input, a third solenoid valve that connects the back chamber of the third opening / closing valve to the oil tank and the descending start command is given to the third solenoid valve when the car descends, and after a predetermined time, the above A control device for a hydraulic elevator, comprising: a control device for giving the above-mentioned descending command to a second solenoid valve. 8. An elevator for supplying pressure oil to a hydraulic jack to raise a car supported by the hydraulic jack, discharging the pressure oil in the hydraulic jack to an oil tank, and lowering the car. A second on-off valve that communicates between the hydraulic pump and the hydraulic jack when rising and slowing down and closes when the car is stopped, and when a lowering stop command is input, the back chamber of the second on-off valve is placed in the oil tank. When the second solenoid valve to be connected, the third opening / closing valve that communicates between the hydraulic pump side of the second opening / closing valve and the oil tank, and the lowering stop command are input, the back chamber of the third opening / closing valve is moved to the oil tank. A third solenoid valve connected to the third solenoid valve, and a controller for giving the second solenoid valve the lowering stop command when the car is descending and giving the third solenoid valve the lowering stop command after a predetermined time. Control device for hydraulic elevator .