JP2000344442A - Energy-saving hydraulic elevator device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an excellent energy-saving effect using a lightweight and compact device by communicating one port of a two-way pump motor with a main cylinder for supporting a loading car, through a main cylinder control valve, and communicating the other port with accumulators through an accumulator control valve. SOLUTION: When a car 6 of a hydraulic elevator is moved up, an operating fluid is discharged from a port on the piping 21 side of a two-way pump motor 2 driven by an inverter-controlled motor 1. The discharge fluid is fed into a main cylinder 4 via a selector valve 3a to advance a ram 43 upward to move up the car 6. At the same time, pistons 53a, 53b are pressed down by the force of springs 55a, 55b of accumulators 5 (5a, 5b) disposed in a space below the car 6 of the elevator, to make the operating fluid in the accumulators 5 flow out and flow into the inlet side of the pump motor 2 via a selector valve 3b. The discharge fluid of the pump motor 2 is further boosted to improve the energy-saving effect of the motor 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an energy-saving hydraulic elevator system, and more particularly to a small and low-cost hydraulic elevator system.

[0002]

2. Description of the Related Art A conventional energy-saving hydraulic elevator uses a balance weight as shown in FIG.

Referring to FIG. 4, the main lifting device (1)
No. 01) has a person and / or load carrying cage (105) attached to a rod (104) of a main cylinder (102), and a balance lifting device (111) is mounted on a rod (114) of a balance cylinder (112). A fixed weight (115) and an adjustment weight (116) are installed, which are approximately equal to the weight of the loaded person and / or load carrying cage (105). Here, the weight of the adjustment weight (116) is set to about 1/2 of the maximum load capacity of the main lifting / lowering device (101). The piston (103) slidably mounted inside the main cylinder (102) is a rod (104).
Is fixed, and can move up and down in the main cylinder (102) together with the rod (104). A piston (113) slidably mounted inside the balance cylinder (112) is fixed to a rod (114), and can move up and down in the balance cylinder (112) together with the rod (114). Also, a double discharge type variable discharge hydraulic pump (1
21) is driven by an electric motor (122), and supplies energy to the rod side chambers (104a) (114a) of the main cylinder (101) or the balance cylinder (111), thereby enabling energy-saving control.

[0004]

In such a conventional hydraulic elevator, the main cylinder and the balance cylinder have substantially the same shape, and a sufficient amount of space is required for installing an apparatus having a balance weight. there were.

[0005]

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem. One of the ports of a two-way pump motor is supported by a loading cage via a control valve for a main cylinder. An energy-saving hydraulic elevator apparatus characterized in that it communicates with a main cylinder and the other port communicates with a pressure accumulator that stores hydraulic oil in a hydraulic circuit via a pressure accumulator control valve and pressurizes the stored hydraulic oil. It is. In this case, as the pressure accumulator, one having a hydraulic oil storage chamber, a piston that pressurizes the hydraulic oil storage chamber, and a coil spring that presses the piston is effective, and furthermore, the mounting length of the coil spring is variable. Doing so is also effective. A safety valve may be provided between the accumulator and the accumulator control valve.

As described above, the present invention employs a pressure accumulator composed of a compact spring device or the like instead of the balance cylinder and the balance weight. Even in a small elevator with a small space, energy can be saved by utilizing the space under the cage. Becomes possible. The spring weight of such a spring device is much lighter than a conventional balance weight, and the use of a plurality of pressure accumulators is short and small, and the spring device is compact even if the spring device is employed.

[0007]

Next, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a hydraulic circuit diagram of a pressure accumulator mounted in a space below an elevator car in the present invention. In FIG. 1, when the basket and the load (6) are raised, they are driven by an inverter-controlled motor (1).
The hydraulic oil is discharged from the port on the pipe (21) side of the directional pump motor (2). The hydraulic oil discharged in this way is
It was supplied from the main cylinder port (41) of the main cylinder (4) into the main cylinder tube (42) through the pipe (21), the switching valve (3a), and the pipe (22), and was connected to the ram (43). Raise the basket and load (6). This time 2
In the hydraulic equipment connected to the inlet side of the hydraulic oil to the directional pump motor (2), the switching valve (3b) is switched to the C side, so that the springs (5a) and (5b) of the accumulators (5a) and (5b)
5a) and (55b) extend to extend the pistons (53a) and (5b).
3b) is depressed and the cylinder tube (52a),
The hydraulic oil in (52b) is supplied to each cylinder port (5
It flows out of 1a) and (51b) and flows into the hydraulic oil inlet side of the two-way pump motor (2) through the pipe (24), the switching valve (3b) and the pipe (23).

When the basket (6) is lowered, the electric motor (1) and the two-way pump motor (2) are rotated in the reverse direction, and the switching valve (3a) is switched to the A side to thereby switch the main cylinder (4).
Hydraulic oil flowing out of the main cylinder port (41) passes through the pipe (22), the switching valve (3a), and the pipe (21).
To the inlet side of the directional pump motor (2),
The hydraulic oil discharged from the directional pump motor (2) is supplied to the ports (51a) and (51b) of the pressure accumulator through the pipe (23), the switching valve (3b) and the pipe (24), and is supplied to the spring (55a). ), (55b) are compressed and the piston (53
a), (53b) are pushed up. In other words, an energy saving effect of the electric motor can be obtained by generating a hydraulic pressure corresponding to the weight of the basket and the load by the accumulator.

In such a hydraulic elevator device,
The equipment weight when using the conventional balance weight,
In comparison with the equipment weight in the case of the present invention example, a hydraulic elevator having a basket weight of 300 kg and a loading weight of 300 kg requires a balance weight of 900 kg, but the compression spring weight in the present invention example is about 100 kg. It is about. Therefore, according to the present invention, it is possible to greatly reduce the equipment weight and make the equipment compact. In FIG. 1, the accumulator (5
Although a) and (5b) show the case of the vertical installation, they may be installed horizontally or any other freely, and the number of accumulators is also arbitrary. In FIG. 1, one coil spring is incorporated in one accumulator, but a plurality of coil springs may be used. Further, as a means for pressurizing the hydraulic oil of the pressure accumulator, any shape spring other than the coil spring may be used, or a means other than the spring may be used. Also, (8a) (8
b) (9a) and (9b) are safety valves for preventing an excessive increase in hydraulic pressure in the circuit.

FIG. 2 illustrates the accumulator used in FIG. First, the lower end is closed, the inner surface of the upper end of a cylinder tube (52) provided with a hydraulic oil port (51) and an air vent port (56) on the side surface of the lower end, and a cover (54) whose upper end is closed by an upper lid. A hollow container is formed by screwing the outer diameter surface of the lower end with a screw or the like. A piston (53) is slidably provided inside the inner diameter of the cylinder tube (52), and the lower end is in contact with the upper surface of the piston (53) and the upper end is in contact with the lower surface of the upper lid of the cover (54). An accumulator having a structure in which the coil spring (55) was provided and the piston (53) was constantly pressed downward was obtained. That is, when hydraulic oil is supplied from the port (51) of the cylinder tube (52), when the pressure exceeds a certain level, the piston (53) is pushed upward against the pressing force of the spring (55). Become. Incidentally, (57) in the drawing is a seal for the piston.

FIG. 3 illustrates another structure of the accumulator. Stopper with long screw (5
9) The long screw portion is penetrated to the outside, the long screw portion is screwed with a nut (60) provided on the upper cover upper surface, and the pressing force can be adjusted by adjusting the stroke of the coil spring (55). I made it. Such a configuration is effective because the spring force of the compression spring can be finely adjusted to the most effective size for energy saving, for example, when the set value of the loaded weight of the basket is changed.

[0013]

As described above, according to the present invention, it is possible to achieve the same energy saving effect as the conventional one by using a lightweight and compact device, and it is possible to sufficiently cope with a small space and to realize a low cost. It has a great effect.

[Brief description of the drawings]

FIG. 1 is a hydraulic circuit diagram showing one embodiment of the present invention.

FIG. 2 is a side sectional view illustrating the pressure accumulator used in FIG.

FIG. 3 is a side sectional view illustrating another example of the pressure accumulator.

FIG. 4 is a hydraulic circuit diagram of an energy-saving hydraulic elevator showing a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electric motor 2 Two-way pump motor 3a, 3b Switching valve 4 Main cylinder 5a, 5b Accumulator 6 Basket and load 8a, 8b, 9a, 9b Safety valve 21, 22, 23, 24 Piping 41 Main cylinder port 42 Main cylinder tube 43 Ram 51, 51a, 51b Cylinder port 52, 52a, 52b Cylinder tube 53, 53a, 53b Piston 54 Cover 55, 55a, 55b Coil spring 56 Air release port 57 Seal 59 Long screw stopper 60 Nut

Claims (4)

[Claims] 1. One port of a two-way pump motor communicates with a main cylinder supporting a loading basket through a control valve for a main cylinder, and the other port in a hydraulic circuit through a control valve for an accumulator. An energy-saving hydraulic elevator apparatus containing hydraulic oil and communicating with a pressure accumulator for pressurizing the stored hydraulic oil. 2. The energy-saving hydraulic elevator apparatus according to claim 1, wherein the pressure accumulator has a hydraulic oil storage chamber, a piston for pressurizing the hydraulic oil storage chamber, and a coil spring for pressing the piston. 3. The energy-saving hydraulic elevator according to claim 2, wherein the length of the coil spring is variable. 4. The energy-saving hydraulic elevator apparatus according to claim 1, wherein a safety valve is provided between the accumulator and the control valve for the accumulator.