JPS60192108A - Oil cooler for hydraulic elevator - Google Patents

Abstract

PURPOSE:To reduce the wastage of cooling water as well as to avoid coming into unstable operation, by detecting a fact that the cooling water flows out of an overflow pipe of a water tank and thereby emitting a warning signal or cutting off a flow of feed water. CONSTITUTION:A flow sensor 13 is installed in an overflow pipe 12 of a water tank 8 storing cooling water, and when a flow rate of water flowing in the overflow pipe 12 goes up beyond the specified value, a warning signal is emitted or feed water to the water tank 8 is intercepted. With this constitution, any wastage in cooling water is reduced and simultaneously unstable operation is avoidable.

Description

[Detailed Description of the Invention] The present invention relates to an oil cooling device for a hydraulic elevator.

[Technical background of the invention and its problems] A hydraulic elevator is an elevator that raises and lowers a car using hydraulic pressure. The blower unit that generates hydraulic pressure consists of an electric motor, hydraulic pump, oil tank, control valve, etc. By rotating the electric motor, the hydraulic pump is fully rotated, sucking oil from the oil tank to generate pressure oil, and the car is raised while controlling the pressure oil with the control valve.

Continuous operation of an elevator increases the number of times the oil passes through the hydraulic pump and control valves, which increases the temperature of the oil. If the temperature of the oil changes, the viscosity of the oil also changes, reducing the running stability of the elevator. To prevent this, K requires complete oil cooling. As a means for this purpose, the most efficient water-cooled cooling device is sometimes used.

FIG. 1 shows an example of this. When the temperature of the oil 2 in the oil tank 1 exceeds a certain value, the electric motor 3 is rotated, thereby rotating the oil pump 4. The oil pump 4 sucks oil 2 from the oil tank 1 and discharges the oil to the water cooler 5.

On the other hand, the water electric motor 6 is rotated in synchronization with the electric motor 3,
Rotate the water pump 7. The water pump sucks cooling water 9'j&: from the water storage tank 8 and discharges the cooling water 9 to the water cooler 5. In the water cooler 5, heat exchange is performed between the high temperature oil 2 and the low temperature cooling water 9,
The oil 2 whose temperature has decreased is returned to the oil tank 1, and the cooling water 9 whose temperature has increased is returned to the water storage tank 8. When this cooling system is continuously operated, the temperature of the cooling water 9 increases, and the heat exchange rate within the water cooler 5 decreases.
Along with this, the cooling effect also decreases. In order to prevent this cooling effect from decreasing, when the cooling water 9 reaches a certain temperature, the drain solenoid valve l0 is fully opened to drain the high temperature cooling water 9, and the water supply solenoid valve 11 is opened to reduce the temperature. Cooling water 9 with a low temperature is supplied. Thereby, the temperature of the cooling water in the water storage tank 8 is lowered.

Furthermore, the amount of water in the water storage tank 8 is controlled by detecting the water surface height with a liquid level gauge (not shown) and stopping the water supply and drainage when the maximum water surface height is reached. Furthermore, in order to prevent the cooling water 9 from overflowing into the water storage tank 8 due to some abnormality, an auto-safe flow pipe 12 is provided to allow the cooling water to naturally flow out before the water storage tank 8 becomes full. Moreover, the outflow of the cooling water 9 from the autosafe flow pipe 12 is something that normally cannot occur, and may be due to a malfunction in some equipment such as a liquid level gauge, a water supply solenoid valve, a drainage solenoid valve, or the like. , due to fluctuations in water pressure of the water supply source, etc. If the cooling device continues to operate in this state, cooling water will be wasted. Furthermore, if any equipment is malfunctioning, the entire cooling system will be in an unstable operating state, which may lead to other malfunctions.

[Purpose of the invention]

The present invention was made in view of the above-mentioned circumstances, and
The purpose is to provide a cooling device that can reduce waste of cooling water and avoid unstable operation.

[Summary of the invention]

The present invention detects that cooling water is flowing out from an overflow pipe of a water storage tank, and issues an alarm or shuts off the water supply.

[Embodiments of the invention]

FIG. 2 shows a cooling device according to an embodiment of the present invention. The same reference numerals in FIG. 2 as in FIG. 1 indicate similar parts, and the device shown in FIG. 2 is generally the same as that in FIG. This is where the flow rate sensor 13 is attached. This flow rate sensor 13 closes a contact S (FIG. 3), which will be described later, when the flow rate of water flowing through the overflow pipe 12 exceeds a predetermined value.

In this way, the sensor 13 whose contacts close only when the flow rate exceeds a predetermined value is used because waves are generated on the water surface of the cooling water 9 in the tank 8 and the overflow pipe 1
This is to ignore the case where a small amount of water flows in 2.

FIG. 3 shows a control circuit that generates an alarm and controls water supply and drainage in accordance with the operation of the sensor 13. In the figure, reference numeral 19 indicates a power supply, and S indicates a normally open contact of the flow rate sensor 13, which closes when the flow rate exceeds a predetermined value. The problem is the flow rate detection relay, which is energized when contact S closes. 20a is a normally open contact of the flow rate detection relay, 21 is an auxiliary relay, SW is a push button switch, 21a is a normally open contact of the auxiliary relay 21,
Contact 20a and auxiliary relay 21 are connected in series, and contact 20a, push button SW, and contact 21a are connected in parallel to form a self-holding circuit. Reference numeral 21b indicates a normally closed contact of the auxiliary relay 21, and 20b indicates a normally open contact of the flow rate detection relay Z. Further, n indicates an alarm circuit, B indicates a water supply solenoid valve control circuit, and san indicates a drainage solenoid valve control circuit.

While the alarm circuit is energized, it generates an alarm, such as by sounding a buzzer in the manager's room, and notifies the manager of an abnormality. When the water supply electromagnetic valve control circuit 23 is energized, water supply control (control based on the temperature, liquid level, etc. of cooling water) is performed. When the power is cut off, the water supply solenoid valve closes and the water supply is cut off. When the drain electromagnetic valve control circuit is energized, the drain electromagnetic valve opens and drains water. The drainage electromagnetic valve control circuit is energized even when a contact (not shown) is closed in order to drain the water as the temperature of the cooling water rises.

When the contact S of the flow rate sensor is closed, the flow rate detection relay 4) is excited, and the contacts 31g and 20b are closed. When contact 20a closes, auxiliary relay 2] is energized and contact 2
1 a f Close and self-hold. Along with the energization of the auxiliary relay 21, the alarm circuit is energized and an alarm is generated. Further, the contact point 21b is opened by the excitation button of the auxiliary relay 2, the water supply solenoid valve control circuit & is de-energized, and the water supply solenoid valve is closed. I, that is, the water supply is cut off. The generation of the alarm and the cutoff of the water supply continue even after the contact '1IJa opens, until the reset pushbutton SW is pressed.

Also, when the flow rate detection relay is energized, contact 2()b
is closed, the drain solenoid valve control circuit is energized, the drain solenoid valve opens, and water is drained. In this way, the contact S and the contact 2 (lb) are synchronized, and when the cooling water 9 fills the water storage tank 8 and flows out from the overflow pipe, the drain solenoid valve 10 is forcibly opened. Drainage takes place.

〔Effect of the invention〕

As described above, according to the present invention, when the water storage tank is full of cooling water and it flows out from the overflow pipe, it is possible to detect this and issue an alarm or cut off the water supply. . Therefore, waste of cooling water can be reduced, and continued unstable operation can be avoided.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing a conventional cooling bag #, FIG. 2 is a schematic diagram showing a cooling device according to an embodiment of the present invention, and FIG. 3 is a diagram showing a control circuit of the cooling device shown in FIG. 8... Water storage tank, 9... Cooling water, lO... Solenoid valve for drainage, 11... Solenoid valve for water supply, 12... Overflow pipe, 13... Flow rate sensor, S... Flow rate sensor contact, B: Alarm circuit, Z3: Water supply solenoid valve control circuit, 24: Drainage solenoid valve control circuit. ■ Middle school 3 mouth 9

Claims (1)

[Scope of Claims] 1. In a device that uses cooling water to cool the oil of a hydraulic elevator that raises and lowers a car using pressure oil, the flow of water in the overflow pipe of a water storage tank that stores the cooling water is detected. An oil cooling system for a hydraulic elevator, characterized in that the oil cooling system is provided with a sensor that generates an alarm or cuts off water supply to the water storage tank when the flow rate of water flowing through the pipe exceeds a predetermined value. 2. The device according to claim 1, wherein the water storage tank is drained when the flow rate exceeds a predetermined value.