JPS5837305A - Method and hydraulic circuit for uniformly distributing liquid flow to plurality of hydraulic operating device by means of pump - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for uniformly distributing liquid flow to a plurality of hydraulically actuated devices by means of a pump. According to this method, the liquid flow of the pump is divided by a rotary distribution device into partial flows which are respectively directed to each actuating device.

In practice, it is often necessary to simultaneously act on a plurality of hydraulically actuated devices on a pressurized liquid supplied by a conventional pump. All actuators are operated simultaneously to prevent the liquid flow produced by the pump from being directed first to the actuator or to the least loaded actuator and to ensure uniform flow distribution among all actuators. It is known in the art to control the distribution of liquid flow produced by a pump in a variety of ways.

1. Flow control valves provided for each actuating device. This solution suffers from difficult and imprecise control and high power losses, especially when the power output changes.

2. Sliding type flow distribution valve. This solution has the disadvantage of a distribution of only two partial flows and a difficult, load-varying and inaccurate control.

6. Rotating distribution device. This solution has the disadvantage that the control varies with load.

4. Actuation devices connected in series. This solution has the disadvantage of increased errors and the use of high supply pressures or large actuating devices.

5. Feedback synchronization. This solution has the drawbacks of being expensive, complex and unreliable in its operation under difficult ambient conditions.

& Pickled control valves for each actuator. Each valve has its own control element. A disadvantage is the difficulty for the driver in controlling each actuator at the same time.

SUMMARY OF THE INVENTION It is an object of the present invention to overcome the above-mentioned disadvantages and to provide a method which allows a uniform distribution of the stone liquid flow produced by the pump to the individual actuators, regardless of any differences in the loads acting on the actuators. be. This object is achieved by the method according to the invention, characterized in that the pressure of the partial stream from the distribution device is adjusted to be higher than the working pressure required for any actuating device by throttling said partial stream.

In the method of the invention, a rotary distribution device is used to distribute the pump power and is known per se to some extent. The distribution device has one flow distribution block for each actuating device, which divides the volume flow from the pump into partial flows depending on the number of pumps. However, the same load is applied to all distribution devices by throttling the partial flow leaving the distribution device. The invention provides that the arrangement ensures that the load on the individual blocks of the distribution device remains constant regardless of any load changes in the actuating device;
It is also based on the idea that the distribution ratio of the distribution device is kept constant. By throttling the sub-streams, the pressure of the sub-streams in the distributor acid is higher than the working pressure required for any actuating device, and the pressure difference between the individual actuators of the distributor remains unchanged, thus Also, even if the partial flow pressure changes after the throttling effect due to a change in the operating pressure of the actuating device, the distribution ratio of the distribution device remains unchanged. The distribution ratio of a rotary distributor is easily maintained even if the pressure difference between the individual disks remains unchanged. However, if the pressure difference changes, the distribution ratio will also change because of the volumetric efficiency of Zoroku, ie the outflow is very dependent on the pressure difference. The method of the invention ensures that the pump power is distributed between the individual actuators regardless of any load changes.

Firstly, the present invention relates to a hydraulic circuit utilizing the above method.

This circuit includes a throttling element in the fluid flow connection between the distributor and each actuating device to adjust the pressure of each partial flow from the distributor to a value higher than the working pressure required for any actuating device. It is characterized by being worn. Depending on this aperture element)
, the value k which remains constant during use due to the fact that the pressure of the partial stream from the distribution v & acid is always higher than the maximum working pressure of the actuating device.
It is possible to have 1N clauses. In this way, the same constant load is obtained for the individual load of the distribution device, which guarantees a constant distribution ratio for the distribution device irrespective of any changes in the working pressure of the actuating device.

The present invention is used, for example, for raising hydraulic cylinders which act on the foundation support of l"J pedestals. In particular, the invention provides a method in which the lowest foundation support is each provided with a control lever, and the remaining support is activated by the same lever. It is suitable for devices with telescoping legs when raised.Furthermore, since absolute accuracy is not required, the invention is commonly used for synchronizing hydraulically operated devices such as cylinders or motors.

Next, the present invention will be explained in detail using a schematic diagram of a hydraulic circuit using the method of the present invention.

In the drawing, a pump 2 driven by a motor 1 is
Connected to the rotary distribution device 4 by a conduit 3, the main body 7Ij
In one example, a distribution device of this type with four individual pumps 5, a pump 2, a conduit 3 and four blocks is used commercially.

Each valve of the distribution device is in turn connected by a conduit 8 to a hydraulically actuated device 9 and by a conduit 6 to a nine pressure control valve 7.

The starting pressure P1 for the pressure control valve 7 is determined by which actuating device a1
9, the supply pressure P of the pump 2 is also adjusted to the same value, higher than the lower working pressure, and the tank pressure of the actuator is designated Pt.

The pump carries on with a supply pressure P8 a liquid flow q which is divided by the individual blocks 5 of the distribution device into four partial streams Q1, the pressure of the partial streams in the conduit 6 being equal to the starting pressure Pl of the valve. All valves therefore have the same starting pressure, and the pressure differences P, -Pl across the distribution device are equal, so that the partial flows ql are always of the same magnitude. The partial flow passes into conduit 8 through valve T and further through actuator 9 for actuating the actuator.

All other pressures, except for the working pressure P2 of the actuating device, are the same for all sensors of the dispensing device.

In the continuous state, each pressure control valve throttles the fluid flow from the block so that the starting pressure Pl remains constant even if the pressure drop Pl-Pg changes as the working pressure P2 of the actuator changes.

[Brief explanation of drawings]

The figure is a schematic diagram of a hydraulic circuit implementing the method of the invention. 2...Pump, 4...Rotary distribution device, 5...Zoroku, 6.8...Conduit, 7...Pressure control valve, 9...
・Hydraulic actuator, Q...liquid flow, C4, x...partial flow, Pl...starting pressure, P2...working pressure, P8・
...Supply pressure. Representatives: Asamura and 4 people

Claims (1)

[Claims] (1) Hydraulic operation by a pump in which the liquid flow (Q) of the pump (2) is guided by a rotary distributor to each actuating device (9) and divided into stone partial flows (Ql). In the method of distributing a liquid flow to a device, the pressure (Pl) of said partial flow (Ql) from said rotary distributor (4) is not required in any actuating device (8) by throttling said partial flow. A method for uniformly distributing a liquid flow to a plurality of hydraulically operated devices by means of a pump, characterized in that the working pressure (P2) of the pump is regulated higher than the working pressure (P2). (2. In the method according to claim 1, the supply pressure (P, ) of the liquid flow (Q) by the pump (2) and the pressure of each liquid fit, (Ql) from the rotary distributor (4) (Pl) is adjusted to the same value. (3) Claim 1 In the method according to paragraph 2, the liquid flow is uniformly distributed (by means of a pump) to a plurality of hydraulically actuated devices, characterized in that each partial flow (Q) is throttled by a pressure control valve (7). Method. (4) Liquid flow (Q
a rotary distribution device (4) which receives a liquid stream (Ql) and divides said liquid stream into sub-streams (Ql), and a plurality of receivers each receiving one of said sub-streams through each flow connection (6, 8). an actuating device (9), wherein the flow connection (6, 8) between the rotary distributor (4) and each actuator is connected to the rotary distributor; Each actuating device 1 (9) K is equipped with a throttle device (7) for adjusting the pressure (Pl) of each partial flow (Qz) from the device to a higher value than the required working pressure [P2]. A hydraulic circuit that distributes liquid flow uniformly to a plurality of hydraulically operated devices by means of a pump. (5) In the hydraulic circuit according to claim 4,
The throttling device (7) has a pressure control valve whose starting pressure (Pl) is regulated to the same value higher than the working pressure (Pg) required for every actuating device (9). , the pressure difference (Pg”) across the individual blocks (5) of the rotary distributor
'