RU2702692C1 - Pressure setting device - Google Patents

Abstract

FIELD: device for adjustment of process conditions.

SUBSTANCE: invention is intended for setting pressure in hydraulic systems in a wide range and with high accuracy at different flow rates. Pressure setter comprises a pump, a standard pressure gauge, an output line, a discharge line and a discharge line. At that, each of pressure and drop lines contains two controlled valves and working chamber of variable volume between valves, wherein reference manometer and outlet line are installed between discharge and discharge lines.

EFFECT: technical result consists in reduction of dimensions and weight.

1 cl, 2 dwg

Description

The invention is intended to set the pressure in hydraulic systems, in a wide range and with high accuracy at different flow rates, by using a pair of controlled valves in the discharge and / or discharge lines, between which a variable volume working chamber is located.

Known designs for setting high pressure (up to 100 MPa) in the hydraulic system using a cylinder, a piston, a pushing screw, a support nut, a gear motor. Such designs are very bulky and heavy due to the large loads on the screw-nut pair.

Known USSR patent No. 1550232, in which by turning the drive shaft opens the fluid inlet to the working chamber, with a further rotation of the axis, this input is closed and the working chamber is connected to the drain. At the same time, the pressure communicated to the working chamber from the inlet contributes to the pressure at the drain, and the larger the ratio of the volume of the working chamber to what is next the drain, the greater the contribution of the inlet pressure. The design drawback is the presence of moving parts and rubber seals, which leads to rapid wear and tear, and there is no way to vary the volume of the working chamber.

A known design (RF patent No. 2044291), in which, for the purpose of setting pressure, controlled check valves and a reference pressure gauge are used. The design is complex due to pneumatic elements.

The aim of the invention is to create a design with a smaller volume and weight, as well as better indicators of the accuracy of the pressure.

For the solution, a design is used in which two controlled valves are installed in one of the lines or in both (discharge, discharge), between which the working chamber is located. In this case, the working chamber is configured to force change its own volume.

Figure 1. shows the structural diagram of the pressure regulator: 1 - control device, 2 - pump, 3 - controlled non-return valve, 4 - working chamber, 5 - controlled non-return valve, 6 - discharge line, 7 - reference pressure gauge, 8 - discharge line , 9 - controlled check valve, 10 - working chamber, 11 - controlled check valve, 12 - outlet line, 13 - manifold, 14 - high pressure connectors, as well as the positions of the working chamber on the example of the working chamber 10: A - maximum volume of the working chamber , B - the average volume of the working chamber, C - the minimum volume of the working cameras.

Figure 2. illustrates the operation of the pressure setter by the example of gauge calibration (the so-called forward and reverse).

Pump 2 delivers a liquid pressure of approximately 20-30% greater than planned at the outlet of the pressure setter. The controlled non-return valves 3 and 5, the working chamber 4 are installed on the discharge line 6, and the controlled non-return valves 9 and 11, the working chamber 10 are installed on the discharge line 8. Before the start of time t1, the outlet pressure is close to zero. The working chamber 4 and the working chamber 10 are brought into a state of minimum volume. At the beginning of the time interval t1, under the control of the control device 1, the controlled check valve 3 opens, the pressure in the working chamber 4 becomes equal to the pressure of the pump 2, then the controlled check valve 3 closes. At the end of the time interval t1, the check valve 5 opens and the pressure of the working chamber is equalized with the pressure of the outlet line 12, then the controlled check valve 5 closes. Due to the fact that the volume of the working chamber 4 is minimal (position B) and significantly less than the volume of the outlet line 12, including the collector 13 and high-pressure connectors 14, the pressure increase is P1 equal to approximately 0.05 MPa. Further, the processes of the time interval t1 are repeated, while the volume of the working chamber is forcibly increased to the maximum (position A) and the pressure increase in the time interval t2 is P2 about 1 MPa. An increase in pressure gain is necessary to accelerate the process of setting the pressure. Then, for a smooth approximation, according to the indications of the reference pressure gauge 7, to the required pressure value (in the experiment, about 30 MPa) in the outlet line 12, the volume of the working chamber again decreases to the minimum (position B) volume by the time interval t3. In this case, manipulations with the volume of the working chamber 4 were carried out with closed check valves 3 and 5.

The time intervals t4, t5, t6 repeat the actions of the time intervals t1, t2, t3 only the working chamber 10 acts as a working chamber, and the controlled non-return valves 9 and 11 act as controlled check valves 3 and 5.

The mass and dimensions of the pressure adjuster were reduced by almost 2 times compared to piston designs using a screw-nut pair at pressures up to 100 MPa.

Claims (1)

A pressure adjuster comprising a pump, a reference pressure gauge, an outlet line, a discharge line and a discharge line, characterized in that each of the discharge and discharge lines contains two controlled valves and a variable volume working chamber between the valves, while the reference pressure gauge and the exit line are installed between the discharge and discharge lines.

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