SU729378A1 - Apparatus for regulating positive-displacement pump - Google Patents

Description

one

The invention relates to a pump engineering industry, relates to devices for regulating volumetric pumps, and can be used in various industries of the national economy in the course of the dosed transfer of various liquids.

Control devices for a volumetric pump are known, comprising a chamber with a movable separator installed therein, a spring element loaded on one side, and with at least one gap for the separator 1.

A disadvantage of the known control devices is the effect of the magnitude of the pressure of the injection or suction on the pump flow, which reduces the accuracy of the flow control. In addition, when landing the separator on the stop during the operation of the device, there are significant shock loads on the stop.

The purpose of the invention is to improve the control accuracy over a wide range of changes in the injection and suction pressure while simultaneously relieving the stops.

The goal is achieved by the fact that the separator is provided with an additional spring element, which loads it in the direction opposite to the first spring element.

FIG. 1 and 2 shows the variants of the design schemes of the regulating device with insensitivity to change.

5 discharge pressure; in fig. 3 and 4 are variants of the regulating device with insensitivity to suction pressure. The control device is connected to the working chamber 1 of a volumetric pump, in which pressure 2 and suction 3 check valves are installed. The separator 4, which interacts with the stop 5, is loaded with two opposing spring elements 6 and 7, at least one of which is equipped with a mechanism

j of regulation, for example, a movable support rod 8. To interact with the stop 5, the separator 4 can be provided with a shoulder 9. The cavity separated from the working chamber 1 by the separator 4, communicated by channel 10 to the pressure line 11

Claims (1)

20 (see Fig. 1). FIG. 3 and 4, this cavity communicates directly with the suction line 12, and the suction valve 3 is installed in the separator 4. FIG. 3, the said cavity is immediately adjacent to the pressure line 11, and the pressure valves 2 are installed in the separator 4. In the diagrams shown in FIG. 2 and 4, the separator 4 is also a displacer of the displacement pump, for which the separator 4 is connected to the drive rod 13 through one of the springs 6 or 7. The displacement of the support rod 8 regulates the gap between the stop 5 and the separator 4 (or its shoulder 9 ) in the equilibrium position of the separator 4, in which the forces of the springs 6 and 7 are equal to each other. When the pump operates, when the discharge pressure (see Fig. 1 and 2) or suction (see Fig. 3 and 4) acts on the side of the separator 4 opposite to the working chamber 1, the separator 4 moves during the suction stroke (see Fig. 1 and 2) or injection (see Fig. 3. and 4) until it stops 5. In this period, the pressure in the working chamber 1 is lower than in the pressure line 11 (see Fig. 1 and 2) or higher than in the suction line 12 (see Fig. 3 and 4). The differential pressure between the working chamber 1 and the opposite cavity communicated with one of the lines 11 or 12 causes the separator 4 to move up to the stop 5. When switching to the discharge stroke (see Fig. 1 and 2) or the suction stroke (see Figures 3 and 4) open the valves 2 or 3, the chamber 1 and the cavity downstream of the separator 4 communicate, and the pressures on both sides of the separator 4 are equalized. The separator 4 is moved to an equilibrium position, into which it turns irrespective of the pressure in lines 11 and 12. In this case the "harmful volume of the working chamber 1 will be equal to the volume described by the separator 4 when it is moved from the stop 5 to the equilibrium state, and The harmful volume does not depend on the pressure of the injection or suction. The "detrimental volume of the working chamber 1" determines the cyclical flow of the pump. The more “harmful volume, the less feed. Regulation of the "harmful volume and pump flow unambiguously, regardless of the injection or suction pressure, is carried out by proportional movement of the supporting rod 8. This changes the equilibrium point position of the separator 4, and therefore the gap between it and the separator 4 and the value" of the harmful volume of the working chamber I. After changing the operation cycles of the pump, the working chamber 1 and the cavity behind the separator 4 are separated by valves 2 or 3, and under the effect of the resulting pressure difference, the separator 4 moves to the stop 5. Pr 6 or 7, countering the movement of the separator 4, softens its fit to the stop 5, reducing the dynamic load on the stop 5. Thus, the proposed device allows to increase the control accuracy by eliminating the influence of the varying pressure value in the pressure head 11 and suction 12 lines, as well as relieve the stop 5. Formula of the invention A device for controlling a displacement pump comprising a chamber with a movable separator installed in it, loaded on one side by a spring element, and with at least about focusing them to the separator, characterized in that, in order to increase the accuracy of control over a wide range varying suction and discharge pressures while simultaneously unloading the abutments, is provided with an additional separator springing element, loading it in the direction opposite to the first springing element. Sources of information taken into account during the examination 1. Britvin L. N. Hydraulic mechanisms for regulating the performance of piston pumps. TSINTIHIMNEFTEMASH, M., 1975, p. 10, fig. 2, , 2 3 4 5 6 eleven