JPS6124293B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a control device for a hydraulic elevator.

In general, in hydraulic elevators equipped with pilot control valves, the acceleration/deceleration is easily affected by changes in oil temperature, and especially in hydraulic elevators where the deceleration distance is set constant in advance according to the elevator rated speed, The deceleration distance is determined in anticipation of changes in oil temperature. However, when the oil temperature drops extremely, the viscosity of the oil increases and the delay in the operation of the pilot control valve increases.As a result, even when the car reaches the deceleration command point and a deceleration command is issued, the delay in the operation of the pilot control valve increases. The car may not be able to slow down enough and may overrun. The above-mentioned problems occur particularly when elevators are operated in winter. The conventional control method to solve this problem is to have a device that keeps the oil temperature in the hydraulic tank above a certain level, park the car on the lowest floor, and always start using the car from the lowest floor after parking is released. Oil kept at a constant temperature in the tank is sent through a control valve to a hydraulic jack to raise the car, and when the car reaches the destination floor, it is immediately returned to the bottom floor after the door is closed unless there is a call from another floor. A floor recall system is used. This prevents problems caused by passengers leaving the floor, in other words, by leaving the floor where the call is answered until the next call is made, the temperature in the hydraulic jack and piping decreases and the temperature inside the hydraulic jack and piping decreases. When a call is made at a floor below the car stop floor, the cold oil in the pipe returns to the hydraulic tank through the control valve, preventing the above-mentioned problems from occurring.

This control method means that if there is no call, the car will be on standby at the bottom floor, and especially in residential buildings, elevators are rarely in full operation except when going to work, and most elevators are on the bottom floor. The car is on standby, and in response to a hall call, the car ascends from the bottom floor, and after answering the hall call, the car returns to the bottom floor after the user has boarded the car and reached the destination floor by calling the car. . However, the lowest floor recall method based on this control method operates regardless of the seasons, and has the following drawbacks.

In response to a hall call, the pump motor is used to raise the car, and after a car call is answered, the door is closed and the call is returned to the lowest floor.
Compared to idle driving, the frequency of use is higher, which causes oil temperature to rise, especially in the summer, and a device to keep the oil temperature below the reference oil temperature is required.

As mentioned above, compared to abandoned driving, power consumption is higher because it is used more frequently.

The present invention was made in order to eliminate the drawbacks of the prior art described above, and an object of the present invention is to provide a control device for a hydraulic elevator that allows stable running without being affected by changes in oil temperature. .

The present invention will be described below with reference to the drawings. A configuration to which the present invention is applicable is shown in FIGS. 1 and 2. 1st
The figure shows a car 1, a hydraulic jack 2, piping 3, and a piping temperature detector 4 provided in the hoistway.
A pipe temperature detector 4 is provided on the pipe 3. Second
The figure shows a control circuit diagram. The set reference temperature is higher than the oil temperature that is stable, that is, the set deceleration distance cannot be maintained.
It closes when T ₀ is reached.

OTR is a pipe temperature detection relay that is pressurized when contact OTH is closed, and OTR1 is a contact that is closed when this pipe temperature detection relay OTR is pressurized. DCR
1 is a contact that closes when the door closes, and is an output contact of a door close confirmation relay (not shown), and 5 is a lowest floor recall circuit.

The operation of the present invention configured as above will be described.
Normally in the summer, the pipe temperature detector 4 does not operate because the pipe temperature is higher than _T0 , so even if car 1 stops at the destination floor in response to a car call and the door closes and contact DCR1 closes. The contact OTH is open and the pipe temperature detection relay OTR is in an open state and the contact
OTR1 is open. Therefore, the lowest floor call-back circuit 5 becomes inoperative, and the car 1 remains stopped at that floor and waits for the next hall call.

Next, as in winter, when the temperature in the hoistway drops and the oil temperature in the piping drops accordingly, the set reference temperature T ₀ is reached before the oil temperature becomes impossible to decelerate, and the piping temperature detector 4 is activated. Then, its output contact OTH closes.
If car 1 is currently being abandoned on a floor other than the bottom floor, contact OTH closes in Figure 2, pressurizes pipe temperature detection relay OTR, and its contact OTR1 closes.
When the contact OTR1 is closed, the contact DCR1 is closed, so that the lowest floor recall circuit 5 operates to recall the car 1 to the lowest floor and make it standby for the next call.

As explained above, according to the present invention, the elevator is not called back to the lowest floor regardless of the oil temperature and is called back only when the oil temperature drops, so that the elevator is not operated unnecessarily, and as a result, power consumption is reduced. In many cases, it becomes unnecessary to install a device that lowers the oil temperature below the reference temperature by eliminating the factors that cause the oil temperature to rise in the car. By calling the elevator back to the lowest floor and waiting for the next call, stable hydraulic elevator operation can be provided to the customers.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a hydraulic elevator to which the present invention is applied, and FIG. 2 is a control circuit diagram of FIG. 1. 1... Car, 3... Piping, 4... Piping temperature detector, 5... Bottom floor recall circuit, OTH... Contact, OTR... Piping temperature detection relay.

Claims (1)

[Claims] 1. Bottom floor recall, where pressurized oil whose temperature is kept within a specified range is supplied and discharged from the cylinder via piping to raise and lower the car, and immediately return to the lowest floor after completing responses to all calls. In a control device for a hydraulic elevator equipped with a device, a temperature sensor is installed in the piping near the cylinder that activates and outputs an output when the temperature falls below a predetermined range, and if there is no output from this temperature sensor, the above A control device for a hydraulic elevator, comprising a device for blocking operation of a bottom floor recall device.