JPH08165065A - Control device for hydraulic elevator - Google Patents

Abstract

PURPOSE: To provide a hydraulic control valve which is simple in construction, low in cost, high in reliability, and high in safety by arranging a downward movement valve in series with an upward movement valve in a main hydraulic line for connecting a cylinder to an upward movement valve delivery port. CONSTITUTION: When an elevator is accelerated, an upward accelerating solenoid valve 11 is controlled and oil is fed into a upward movement valve pilot chamber 13 so as to pressurize an upward movement valve pilot valve. By this, the upward movement valve 10 is closed gradually. When a pump port pressure becomes higher than a cylinder port pressure, the oil delivered from a pump opens a downward movement valve 20 and flows into a cylinder 2, raising a car 1. In downward accelerated operation, a downward accelerating solenoid valve 21 is controlled to flow oil from a downward movement valve pilot chamber to a pump port so as to reduce a downward movement valve pilot chamber pressure for opening the lower movement valve. Also, after a trouble of the downward movement valve 20 is detected by some means, the upward accelerating solenoid valve 11 is controlled so as to fully open the upward movement valve 10 for stopping a car.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic elevator control device.

[0002]

2. Description of the Related Art The main components of a control valve of a conventional electric-hydraulic control type hydraulic elevator are an ascending valve, a descending valve, and a check valve, and the ascending valve and the check valve are connected in series. ，
A solenoid valve for ascending acceleration, a solenoid valve for ascent and deceleration, a solenoid valve for ascent and deceleration, and a solenoid valve for ascent and deceleration are attached to the descending valves, respectively.

In the ascending operation, first the pump is driven,
All the hydraulic fluid discharged from the pump returns to the tank (total bleed-off). By adjusting the solenoid valve for ascending acceleration and the solenoid valve for ascending / decelerating, the rise valve pilot chamber pressure is adjusted,
Controls the lift valve opening. During acceleration, the riser valve is closed to reduce the amount of oil returned to the tank and increase the pump port pressure. As a result, the hydraulic fluid pushes open the check valve and flows into the cylinder.

In the descending operation, the speed of the hydraulic oil discharged by the weight of the plunger and the car is controlled by controlling the opening degree of the descending valve. The lowering valve opening degree is controlled by controlling the lowering valve pilot chamber pressure as in the case of the rising valve.

In Japanese Patent Laid-Open No. 55-155662, there is provided a lowering control device in which an electric motor is rotatably connected to a hydraulic pump. When the car is lowered, the hydraulic pump discharged from the hydraulic jack is driven to drive the hydraulic pump. In the one that controls the lowering operation of the car by the dynamic braking of the electric motor, the abnormality detection device that operates due to the abnormality of the lowering control device and the discharge of the pressure oil from the hydraulic jack that is biased through the operation of the abnormality detection device A control device for a hydraulic elevator is invented, which is provided with a flow rate control device that restricts the amount.

[0006]

Since the conventional hydraulic control valve is composed of three valves, an ascending valve, a descending valve and a check valve, the structure is complicated and expensive.

Further, in the conventional method, when the descending valve and the electromagnetic valve for accelerating the descending force are stuck during the descending operation, the oil cannot be prevented from flowing out from the cylinder, which is very dangerous.

When the elevator is stopped for a long time, the leakage of oil from the check valve and the leakage of oil from the down valve are large, and the sinking of the car becomes a problem.

An object of the present invention is to provide a hydraulic control valve which is simple in structure, inexpensive, and highly reliable and safe.

[0010]

In order to achieve the above object, the present invention provides a pump or a drive device for driving a pump, in which an ascending valve and a descending valve (check valve) are arranged in series between a cylinder and a tank. It is characterized in that braking control is provided in the.

Further, in the hydraulic elevator having the above-mentioned structure, the lowering valve and the solenoid valve for lowering acceleration are controlled by controlling the speed during the lowering operation by the lowering valve and the ascending valve connected in series with the lowering valve. Even in the case of a failure in the open state, it is possible to prevent the car from lowering by controlling the lift valve, and it is also possible to unload the elevator passenger at a safe position.

[0012]

[Operation] By arranging the ascending valve and the descending valve in series between the cylinder and the tank, during the ascending operation, the pump is driven to control the ascending acceleration solenoid valve and the ascending / decelerating solenoid valve, and the ascending valve pilot It controls the chamber pressure and controls the opening and closing of the rising valve. When the rise valve is closed, the pump port pressure rises, and when it rises above the cylinder pressure, the hydraulic fluid discharged from the pump pushes down the down valve (check valve) and flows into the cylinder. During the descent operation, the descent acceleration solenoid valve and the descent deceleration solenoid valve are controlled to control the descent valve pilot chamber pressure and to control the descent valve opening and closing. When the down valve is opened, the hydraulic fluid in the cylinder is discharged due to the weight of the plunger and the car.
The car descends.

When the descending valve or the solenoid valve for decelerating acceleration becomes tight, the solenoid valve for ascending acceleration is fully opened and the solenoid valve for ascending / decelerating is fully closed to increase the pressure in the ascending valve pilot chamber and close the ascending valve. If you are using a reversible pump,
By operating a braking device attached to a pump or a motor that rotates in conjunction with the pump, the oil in the cylinder can be prevented from flowing out and the sinking of the car can be prevented.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a hydraulic elevator control apparatus according to the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a hydraulic circuit of a hydraulic elevator according to the present invention, FIG. 2 is an operation timing chart in normal times, and FIG. 3 is an operation timing chart in the case of an abnormality assuming that the down valve is stuck during down operation. FIG. 4 is an operation timing chart when the descending operation is controlled by using two valves, an ascending valve and a descending valve.

In the figure, 1 is a car, 2 is a cylinder, 3 is a piston, 4 is a pipe, 5 is a pump, 6 is a motor, 7 is a braking device for suppressing the rotation of the pump, 8 is a tank, and 10 is. Ascending valve, 11 is an ascending solenoid valve (normally closed), 12 is an ascending / decelerating solenoid valve (normally open), 13 is an ascending valve pilot chamber, 20 is a descending valve (check valve), and 21 is an ascending solenoid. Valve (normally closed), 22 is a solenoid valve for downward deceleration (normally open),
Reference numeral 23 is a down valve pilot chamber, and four solenoid valves 11,
A coil 30 and a spring 31 are provided at 12, 21, and 22, respectively.
Is attached. 32 is a pump port and 33 is a cylinder port.

Next, the operation will be described.

Before the ascending operation is started, the ascending valve is fully open and the descending valve is fully closed. When the motor 6 is driven after the braking device 7 is opened, the pump starts to rotate at a constant rotation speed, and the hydraulic fluid discharged from the pump returns to the full tank through the rising valve orifice (full bleed-off). During elevator acceleration, the ascending acceleration solenoid valve 11 is controlled and oil is sent into the ascending valve pilot chamber 13 to pressurize the ascending valve pilot valve. As a result, the rising valve 10 is gradually closed. When the pump port pressure becomes higher than the cylinder port pressure, the pump discharge oil pushes open the down valve 20, flows into the cylinder 2, and the car 1 rises. During deceleration, the ascending / decelerating solenoid valve 12 is controlled to return the oil in the ascending valve pilot chamber 13 to the tank 8 to gradually open the ascending valve. As a result, the amount of pump discharge oil returned to the tank 8 increases, the flow rate of the oil flowing to the cylinder 2 decreases, and the car slows down.

During the downward operation acceleration, the downward acceleration solenoid valve 21 is controlled to flow oil from the down valve pilot chamber to the pump port to reduce the pressure in the down valve pilot chamber. As a result, the lowering valve is opened, the oil of the cylinder 2 is discharged to the tank 8 through the pump port 32 by the weight of the car and the plunger, and the car is accelerated.

The timing chart of FIG. 2 shows a series of operations of the ascending and descending operations.

FIG. 3 is an operation timing chart in the case where the down valve is stubborn during the downward deceleration in the control according to the operation timing chart of FIG. After the failure of the descending valve 20 is detected by some means, the ascending solenoid valve 11 is controlled to fully close the ascending valve 10 and stop the car.

FIG. 4 is an operation timing chart when the entire range from the start to the stop during the descent operation is controlled using the ascending valve 10 and the descending valve 20. In the case of the control system shown in FIG. 4, even if the down valve is tight, the same speed characteristic as in normal times can be obtained. If the pump port volume is reduced and the ascending valve 10 and the descending valve 20 are fully closed when the elevator is stopped, it is possible to suppress the sinking of the car due to oil leakage during a long stop. .

In FIG. 1, the solenoid valve 11 for upward acceleration is used.
Although one end of is connected to the cylinder port 33, it can be connected to the pump port 32.

Although the electric-hydraulic control system has been described in this embodiment, a mechanical-hydraulic control system in which valve opening / closing control is performed by a mechanical throttle instead of an electromagnetic valve, and a total hydraulic control system in which all control is performed only by hydraulic pressure. It is also applicable to the elevator.

[0025]

According to the present invention, since the hydraulic control valve is composed of the ascending valve and the descending valve, it is possible to provide a small and inexpensive hydraulic control valve having a simple structure.

Further, even if the descending valve is in an open state and becomes tight, the elevator can be controlled to stop the car, so that a highly reliable and safe hydraulic elevator can be provided. it can.

Even when the hydraulic elevator is stopped for a long time, by keeping the ascending valve and the descending valve connected in series in the fully closed state, it is possible to suppress the car subsidence due to oil leakage, so that it is possible for the elevator users The service can be improved.

[Brief description of drawings]

FIG. 1 is a hydraulic circuit diagram of a hydraulic elevator that is an embodiment of the present invention.

FIG. 2 is a timing chart of normal operation of the hydraulic control valve that is an embodiment of the present invention.

FIG. 3 is an operation timing chart of the hydraulic control valve when the down valve is tightly agitated.

FIG. 4 is an operation timing chart of a hydraulic control valve that is an embodiment of the present invention.

[Explanation of symbols]

1 ... Car, 2 ... Cylinder, 3 ... Piston, 4 ... Piping, 5 ... Pump, 6 ... Motor, 7 ... Braking device, 8 ... Tank.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kyora Nishihara 1070, Ige, Hitachinaka City, Ibaraki Prefecture Hitachi Ltd. Mito Plant

Claims (2)

[Claims] 1. A hydraulic elevator that performs bleed-off control during ascending operation and meter-out control during descending operation,
A hydraulic elevator control characterized in that the hydraulic control valve for controlling the elevator is composed of an ascending valve and a descending valve, connecting the cylinder and the ascending valve discharge port, and arranging the descending valve in series with the ascending valve with respect to the main oil flow path. apparatus. 2. The hydraulic elevator control device according to claim 1, wherein the descending valve can be controlled and the ascending valve can be controlled during a descending operation.