JPH07125936A - Control device for hydraulic elevator - Google Patents

Abstract

PURPOSE:To prevent an elevator from being disabled due to a start lock when the oil temperature is decreased by temporarily increasing the oil temperature at the time of an operation restart after a power source is cut off for a long period in the low-oil temperature state, then lowering a car to the lowest floor, and again increasing the oil temperature to a fixed value or above. CONSTITUTION:In a hydraulic elevator having a plunger provided with a car at the head section, a descent control block is operated based on the first detection signal at the prescribed value or below of an oil temperature sensor, and an oil temperature increasing circuit is operated based on the detection signal at the prescribed value or below of the oil temperature sensor and the operation signal of a stop position detecting switch detecting the lowest floor position of the car. A means detecting a prescribed value lower than the prescribed value of the oil temperature sensor is provided, and the oil temperature increasing circuit is operated without moving the car when the car is located at a floor other than the lowest floor based on the second detection signal. When the first detection signal is detected, the descent control block is operated, and the oil temperature increasing circuit is again driven when the car reaches the lowest floor.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for a hydraulic elevator, and more particularly to a device for maintaining the oil temperature of the hydraulic elevator at an appropriate temperature.

[0002]

2. Description of the Related Art Generally, in a hydraulic elevator, when the temperature of oil changes, the viscosity changes, and when the oil temperature decreases, the viscosity increases. This affects the performance of the flow control valve in the hydraulic circuit, and therefore, even if an operation command is given to the flow control valve,
The time required for flow rate control becomes longer. As a result, the deceleration becomes small, the distance required for deceleration becomes long, and the vehicle stops by going too far.

Therefore, there has been conventionally invented a device for raising the oil temperature when the oil temperature is low.

For example, Japanese Laid-Open Patent Publication No. 3-23166 and Japanese Utility Model Laid-Open No. 57-81.
No. 266 publication.

[0005]

In the conventional hydraulic elevator, an oil temperature detector is provided in the oil tank, and when the oil temperature falls below a predetermined value, the car is removed when the elevator is not on the lowest floor. When descending to the bottom floor and arriving at the bottom floor, the oil temperature raising circuit is activated to keep the oil temperature at an appropriate temperature, but the power is cut off for a long time while the car is parked on the top floor or middle floor. If the oil temperature is abnormally lowered when the power is turned on again, the car will be lowered to the lowest floor to increase the oil temperature as before, but both the plunger and the oil tank will be increased. The oil temperature is abnormally low and the oil viscosity is abnormally high. When the car tries to descend to the lowest floor, the startup lock may occur and the elevator may become inoperable.

An object of the present invention is to lower the car to the lowest floor and operate the oil temperature raising circuit in the hydraulic elevator, but prevent the elevator from being inoperable due to the start lock when the car is lowered to the lowest floor. Especially.

[0007]

SUMMARY OF THE INVENTION The hydraulic elevator of the present invention increases the oil temperature even when the car is not on the lowest floor based on a detection signal for detecting that the oil temperature is below a predetermined value and is abnormally low. A means for operating the operating circuit to raise the oil temperature in the tank, and the oil temperature raising circuit is stopped based on the detection signal that detects that the oil temperature has risen to a temperature at which the car can be lowered, and the car is moved to the bottom floor. Based on the operation signal of the lowering means and the stop position detection switch that detects the lowest floor position of the car, the oil temperature raising circuit is operated again to raise the oil temperature to a predetermined value, and the oil temperature sensor has a predetermined value or more. And an oil temperature raising circuit drive stopping means for stopping the operation of the oil temperature raising circuit based on the detection signal.

[0008]

According to the present invention, the oil temperature sensor detects when the oil temperature in the oil tank is below a predetermined value and becomes abnormally low.
Based on this detection signal, the car operates the oil temperature increasing circuit even when the car is not on the lowest floor. Based on the detection signal that detects that the oil temperature has risen to a temperature at which it can be lowered, the oil temperature raising circuit is stopped and the car is lowered. When the basket is at the bottom floor,
The stop position detection switch detects this and operates the oil temperature raising circuit again to raise the oil temperature to a predetermined temperature. When the temperature becomes equal to or higher than a predetermined value, the operation of the oil temperature raising circuit is stopped based on the detection signal of the oil temperature sensor equal to or higher than the predetermined value. Therefore,
Even if the oil temperature is abnormally low, it does not cause a start lock,
It is possible to lower the car to the lowest floor and raise the oil temperature to room temperature.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment according to the present invention will be described in detail below with reference to the drawings.

1 detects that the oil temperature is abnormally low (predetermined value A) after long-term power-off. The abnormally low oil temperature indicates a temperature at which the elevator may become inoperable due to activation lock when the elevator is operated in this state. In the case of 2 and 1 in the state of 1, the oil temperature raising circuit is operated even if the car position is other than the lowest floor. As a result, the temperature of the oil in the oil tank can be raised. No. 3 detects that the oil temperature has risen to a temperature at which the elevator can operate (predetermined value B).
Unless the predetermined value B is detected, the oil temperature raising circuit continues to operate on the spot. 4 detects that the car position is the lowest floor. When the lowest floor is detected in 4, the oil temperature raising circuit is continuously operated as it is. No. 9 detects that the oil temperature has risen to an appropriate temperature (predetermined value C) that does not cause a problem when the elevator operates. Since No. 10 detects that the oil temperature has reached an appropriate temperature, the operation of the oil temperature raising circuit is stopped.

Next, an example in which the car position is detected at a position other than the lowest floor in 4 will be described.

Since it is detected in 4 that the car position is not on the lowest floor, the car must be lowered to the lowest floor. At 5, the operation of the oil temperature raising circuit is once stopped in order to lower the car. This is because the valve used for raising and lowering the car is different from the valve used for raising the oil temperature, so that the motor is temporarily stopped and the valve used is switched. At 6, the car is lowered to the bottom floor. 7 has detected that the car has arrived at the bottom floor. No. 8 operates the oil temperature increasing circuit based on the fact that the car is stopped at the lowest floor at 7. Then, at 9 it is detected that the oil temperature has risen to an appropriate temperature (predetermined value C) that does not cause a problem in the operation of the elevator, and at 10 the operation of the oil temperature raising circuit is stopped.

[0013]

[Effects of the Invention] When the power is turned on when the oil temperature is abnormally lowered due to long-term power interruption, etc., the oil temperature is raised even if the car is not on the lowest floor, and if the car temperature rises to a lowerable oil temperature. , The car is lowered to the lowest floor without starting lock, and the oil temperature including the oil in the cylinder is raised again to a certain value or more, so even if the oil temperature is abnormally low, The oil temperature is maintained at an appropriate temperature without causing elevator operation failure, and the elevator specifications are not compromised.

[Brief description of drawings]

FIG. 1 is a flowchart for determining an operating condition of an oil temperature raising circuit according to an embodiment of the present invention.

[Explanation of symbols]

1 ... Oil temperature sensor detects a predetermined value (A) or less, 2 ... Oil temperature rising circuit operation, 3 ... Predetermined value (B) of oil temperature sensor, 4 ...
Car position determination, 5 ... Oil temperature raising circuit stopped, 6 ... Elevator lowering, 7 ... Car position determination, 8 ... Oil temperature raising circuit operation, 9 ...
Determination of predetermined value (C) of oil temperature sensor, 10 ... Oil temperature rising circuit stopped.

Claims (1)

[Claims] 1. A cylinder and a vertical movement in the cylinder,
A hydraulic elevator including a plunger having a basket on its head, a tank for storing oil, a hydraulic pump for sucking oil in the oil tank, the hydraulic pump, and a cylinder provided between the hydraulic pump. A hydraulic circuit having an ascending control block for controlling the supply of the oil sucked up by the pump to the cylinder and a descending control block for controlling the return of the oil in the cylinder to the oil tank, and an oil provided in the hydraulic tank for detecting the oil temperature. A descending control block drive means for operating a descending control block based on a first detection signal having a temperature sensor and being less than or equal to a predetermined value of an oil temperature sensor provided in the hydraulic circuit, and a predetermined value of the oil temperature sensor. An elevator having an oil temperature raising circuit driving means for operating the oil temperature raising circuit based on the following detection signal and the operation signal of the stop position detection switch for detecting the lowest floor position of the car. On the basis of the means for detecting a predetermined value lower than the predetermined value of the oil temperature sensor and the detected second detection signal, even if the car is not on the lowest floor, the car is moved as it is. Without operating the oil temperature raising circuit, and once the first detection signal is detected, the oil temperature raising circuit operation is temporarily stopped and the lowering control block is operated, and the lowest floor position of the car is detected. And a means for driving the oil temperature raising circuit again based on the operation signal of the stop position detection switch.