JP3036646U - Hydraulic elevator equipment - Google Patents

Abstract

(57) 【Abstract】 PROBLEM TO BE SOLVED: For a hydraulic elevator that has a main control valve for circulating hydraulic oil in both forward and reverse directions, and raises and lowers a car by controlling the amount of hydraulic oil discharged from the hydraulic pump, As a measure against a free run, if the opening of the main control valve is limited to suppress the speed of the free run, the load on the electric motor will increase during the ascending operation. SOLUTION: A check valve 10 is connected in series with a main control valve so that a hydraulic oil is supplied in a forward direction to a hydraulic jack.
And the poppet 11 of this check valve 10
By making the hole 11a in the hole and allowing the hydraulic oil to flow in the opposite direction, the pressure loss in the descending direction becomes larger than the pressure loss in the ascending direction.

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 The present invention relates to a hydraulic elevator, and more particularly to a hydraulic elevator that controls the amount of oil discharged from a hydraulic pump driven by this electric motor by controlling the electric motor by inverter control or the like.

[0002]

[Prior art]

 An example of a conventional hydraulic elevator will be described with reference to FIG. In the figure, 1 is a hydraulic jack for raising and lowering a car 2, 3 is a control unit for driving a hydraulic pump 5 by controlling an electric motor 4, 6 is a tank, 7 is a main control valve, and 7a is a solenoid coil.

When the car 2 is raised, the hydraulic pump 5 is rotationally controlled and hydraulic oil is supplied to the hydraulic jack 1 via the main control valve 7 to raise the car 2. Further, when the car 2 is lowered, the solenoid coil 7a is excited to fully open the main control valve 7 and the hydraulic pump 5 is rotationally controlled to discharge hydraulic oil from the hydraulic jack 1 to lower the car 2.

By the way, in the case of the hydraulic elevator shown in FIG. 2, if a power failure occurs during the descending operation of the car 2 at a low speed, the car 2 may cause a free run. This is because the main control valve 7 is fully opened and the hydraulic pump 5 is controlled to control the flow rate of the hydraulic oil during the descent operation. Therefore, if a power failure occurs during low-speed descent operation, the electric motor 4 stops, while the main control valve 7 is fully open, so the flow rate of hydraulic oil increases rapidly, and the car 2 enters the free-run state. Thereafter, as the main control valve 7 is closed, the car 2 is decelerated, and when the main control valve 7 is completely closed, the car 2 is stopped.

As a measure against this free run, a method of limiting the opening of the main control valve 7 at the time of full opening to such an extent that hydraulic oil can pass during the rated speed operation of the car 2 has been considered. According to this method, the flow rate of the hydraulic oil at the start of the free run is limited as compared with the conventional method, so that the speed of the free run can be suppressed.

[0006]

[Problems to be solved by the device]

 If the opening degree of the main control valve 7 is limited, the flow rate of the hydraulic oil is limited not only during the descending operation but also during the ascending operation, resulting in a large pressure loss and a large load on the electric motor 4. Occur.

Further, if the opening degree of the main control valve 7 is set large, the pressure loss becomes small, but the acceleration at the start of the free run becomes large. Therefore, various safety devices are used to forcibly stop the car 2. Even if it does, the abnormal traveling distance until the car 2 stops becomes long. Therefore, when driving with the door of the car 2 open such as in the re-leveling operation or the inching operation, passengers and luggage are getting on and off, which is very dangerous.

[0008]

[Means for Solving the Problems]

 The present invention is provided with a device, which has a small pressure loss during the ascending operation and a required pressure loss during the descending operation, in series with the main control valve.

[0009]

[Embodiment of the invention]

 In the embodiment of the present invention, a check valve is arranged in series with the main control valve so that the direction in which hydraulic oil is supplied to the hydraulic jack is the forward direction. It is configured such that the hydraulic oil also flows in the direction.

Further, another embodiment of the present invention is such that the hole of the poppet is made larger than a size through which hydraulic oil can pass when the car is operated at a rated descent speed.

[0011]

【Example】

 One embodiment of the present invention will be described with reference to FIG. The drawing shows a check valve 10, in which 11 is a poppet, 11a and 11b are holes formed in the poppet 11, and 12 is a compression ring. The check valve 10 is arranged in series with the main control valve 7 shown in FIG.

Explaining the operation of the present embodiment, the hydraulic oil flows from the hydraulic pump 5 side to the check valve 10 (forward direction) during the ascending operation. While the flow rate of hydraulic oil is small, it flows to the hydraulic jack 1 side through the hole 11a, but the flow rate increases and the pressure loss generated when passing through the hole 11a exceeds the force of the spring 12 (opening pressure). Then, the poppet 11 moves and opens the valve. Since the hydraulic oil flows from both the holes 11a and 11b to the hydraulic jack 1 side, if the pressing force of the spring 12 is set to be small, the pressure loss during the ascending operation will be small, and the load on the electric motor 4 will be reduced. Can be made smaller.

During the descending operation, the hydraulic oil flows from the hydraulic jack 1 side to the hydraulic pump 5 side (reverse direction) only through the hole 11a and does not pass through the hole 11b, so that a large pressure loss is generated as compared with the ascending operation. Occurs. The hole 11a is set to have a size larger than the size through which the hydraulic oil can pass during the operation of the lower rated speed of the car 2.

As described above, according to the present embodiment, the pressure loss is small during the ascending operation and the necessary pressure loss is obtained during the descending operation, so that the load on the electric motor 4 can be reduced and the free running can be achieved. The speed and acceleration of the car 2 can be suppressed.

In the above embodiment, if the check valve 10 is provided in the vicinity of the oil port of the hydraulic jack 1, an earthquake or the like may damage the piping or the like between the check valve 10 and the tank 6, causing the car 2 to be in a free-run state. Even if it does, its speed and acceleration can be limited. Further, although the in-line type check valve is shown in the above embodiment, a right angle type check valve in which the inlet and the outlet of the hydraulic oil are at right angles to each other can be similarly applied.

[0016]

[Effects of the Invention] As described above, according to the present invention, it is possible to obtain the necessary pressure loss during down operation while suppressing an increase in the load on the electric motor. The speed and acceleration of time can be suppressed. In addition, by controlling the speed during free run, it is possible to shorten the abnormal mileage of the car until the car is forcibly stopped by various safety devices, etc., so the car floor during releveling operation and inching operation It is possible to reduce the deviation from the floor, improve safety, and reduce the anxiety felt by passengers. Furthermore, since the device of the present invention is small, it can be easily applied to an existing hydraulic elevator.

[Brief description of the drawings]

FIG. 1 is a view showing a check valve according to an embodiment of the present invention.

FIG. 2 is a schematic diagram showing the entire configuration of a conventional hydraulic elevator.

[Explanation of symbols]

 1 hydraulic jack 2 car 3 control part 4 electric motor 5 hydraulic pump 7 main control valve 10 check valve 11 poppet 11a, 11b hole

Claims (3)

[Utility model registration claims] A hydraulic jack for raising and lowering a car; a hydraulic pump for supplying and discharging hydraulic oil to and from the hydraulic jack; and a hydraulic pump disposed between the hydraulic jack and the hydraulic pump;
With a main control valve that allows hydraulic oil to flow in both the forward and reverse directions, a means is provided in series with the main control valve that makes the pressure loss during the descending operation larger than the pressure loss during the ascending operation of the car. A hydraulic elevator device characterized in that 2. A hydraulic jack for raising and lowering a car, a hydraulic pump for supplying and discharging hydraulic oil to and from the hydraulic jack, and disposed between the hydraulic jack and the hydraulic pump;
With a main control valve for circulating hydraulic oil in both forward and reverse directions, a check valve is arranged in series with the main control valve so that the direction in which hydraulic oil is supplied to the hydraulic jack is forward. A hydraulic elevator device characterized in that a hole is provided in the poppet of the check valve so that the hydraulic oil flows in the opposite direction. 3. The hydraulic elevator according to claim 2, wherein the hole of the poppet has a size that is equal to or larger than a size through which the hydraulic oil can pass during the downward rated speed operation of the car.