SU1298419A1 - Control hydraulic system for variable pressure pump - Google Patents

Abstract

This invention relates to engineering hydraulics. The purpose of the invention is to improve the dynamic x-pump. For this purpose, the spool 6 of the distributor (P) 5 is made with one throttling and two separating edges (K) 7, 9 and 10. The throttling K 7 forms with the casing a throttle 8 connecting the pump 1 with the piston cavity (P) 4 of the control hydraulic cylinder 2. The separators K 9 and 10 are located respectively between lines 11 and 12, which communicate with P 4 with a drain, and lines 14 and 15, which communicate pump 1 with P 16 hydraulic control P 5. P 16 communicate with drain through throttle 17, P 18 control P 5 has a larger diameter and communicates with the pump 1, and its spring P 19 communicates with the drain. With increasing load and pressure in the P 18, the spool 6 is displaced, together the pump 1 with the P 16, and the P 4 of the hydraulic cylinder 2 - with a drain, which leads to a decrease in the pump flow. 2 h. n. f-ly, 3 ill. i (L 7J Yu ac QD FIG.

Description

The invention relates to engineering hydraulics and can be used in pumping stations of variable feed hydraulic systems.

The purpose of the invention is to improve the dynamic characteristics.

FIG. 1 is a diagram of a pressure-controlled pump hydraulic system; in fig. 2 is a hydraulic system diagram supplemented with a continuous distributor; in fig. 3 - diagram of the hydraulic system with a reversible pump.

The hydraulic system (Fig. 1) contains an adjustable pump 1 with a regulating body in the form of a hydraulic cylinder 2 with a rod and a spring-loaded piston cavity 3 and 4, a hydraulically controlled spring-loaded spool four-line valve 5 with a differential three-edge spool 6, one of the edges 7 of which forms the first throttle 8 through which the pump 1 is connected to the piston cavity 4 of the hydraulic cylinder 2, the rod cavity 3 of which is connected to the pump 1, and the other two edges 9 and 10 are installed respectively between lines 11 and 12, communicating polo 4 hydraulic cylinders 2 with a drain 13, and lines 14 and 15, which connect the pump 1 with the hydraulic control cavity 16 of the distributor 5, which, in turn, is connected to the drain 13 via the second throttle 17, and the second control cavity 18 of the distributor 5 of larger diameter is connected with the pump 1, and the spring cavity 19 is connected to the drain 13.

The hydraulic system (Fig. 2) further comprises an electrically controlled three-edged spool valve 20 of continuous operation, which communicates the spring cavity 19 of the distributor 5 with either a drain 13 or a control pressure source 21.

The hydraulic system (FIG. 3) is supplemented with a second control pump 22, an electrically controlled four-line distributor 23, a hydraulic-controlled five-line spool choke divider 24 and check valves 25, the pump 1 being reversible. The line 11 of the distributor 5 is connected to the cavity 4 of the hydraulic cylinder 2 via the distributor 23 and the divider 24, through which the cavity 3 of the hydraulic cylinder 2 is connected to the pump 1. The pump 22 is connected to the line 14 of the distributor 5 and through one of the check valves 25 to the pump 1, which It is connected to the control valve cavity 18 of the distributor 5.

The hydraulic system works as follows.

In the absence of load and, consequently, pressure in the cavity 18 of the control of the distributor 5, the spool 6 is in the left (Fig. 2) position, and the hydraulic cylinder 2 is in the position corresponding to the maximum flow of the pump 1. While increasing the load and pressure in the cavity 18, the spool 6

moves to the right, together the pump 1 with the cavity 16 of the distributor 5, and the cavity 4 of the hydraulic cylinder 2 - with the drain 13, which leads to a decrease in the flow of the pump 1.

When the distributor 20 supplies the control pressure source 21 to the cavity 19 of the distributor 5 (Fig. 2), the dynamics of the displacement of the spool 6 to the right changes (slows down) in proportion to the pressure in the cavity 19 ,; specified by the distributor 20.

5 Hydraulic system (Fig. 3} works similarly to the system shown in Fig. 2, when using reversible pump 1.

Claims (3)

1. The hydraulic control system of a pressure-controlled pump, comprising a pressure source containing at least one adjustable pump with a regulating member in the form of a spring-loaded 5 of a two-cavity cylinder, the springless cavity of which is connected to the pump, a hydraulically controlled spring-loaded control spool, whose first line and the control cavity are connected to a pressure source, the second line is connected to the spring cavity of the two-cavity cylinder, and a third line and the spring cavity are connected to a drain, the first choke, mounted in the communication line of the cavities of the double cavity, between them, the second choke and A pressure source unloading device, characterized in that, in order to improve the dynamic characteristics, the control spool is made three-fold, placed in the housing to form an additional hydraulic control cavity and provided with a fourth line, one of the edges is made throttling, forming the first throttle with the housing, and is installed between the first and second lines, the second edge, separating, is installed in the case between. the second and third lines, and the third edge, also dividing, is made of a larger diameter, forms with the body the main control valve hydraulic control cavity and a pressure source discharge device and is installed between the first and fourth lines, with the fourth line connected directly to the additional control cavity and through the second choke - with a drain. 2. A hydraulic system according to claim 1, characterized in that it is equipped with an electrically controlled three-edged spool valve of continuous action, two lines installed in the communication line spring 0 five the spool valve control with a drain, and the third line connected to the pressure source. 3. The hydraulic system for PP. 1 and 2, characterized in that the pressure source contains two pumps - adjustable and auxiliary unregulated, connected to a common drive; the hydraulic system is equipped with an electrically controlled four-line distributor, hydraulically controlled filamentary slide valve and separating elements valves installed in the connection lines for the inlet and outlet of the reversing pump with the first line of the control spool and its main hydraulic chamber, the auxiliary pump is connected to the first line of the control lotter, four-line distributor and spool choke divider are installed successively in the communication line of the second control spool line with the spring cavity of a two-cavity cylinder, the rod of which is connected with the throttle control body of the spool chopper, each four-line distributor is connected to one of the hydraulic control cavities spool choke divider, the first of the lines of which is connected to the drain, the second - to the spring cavity of the two-cavity cylin core, third and fourth - with the main hydraulic control shaft of the control spool, and the third with the springless cavity of a two-cavity cylinder, the spring of which is equipped with a mechanism for holding the cylinder rod in the middle position in the initial position. FIG. 2 FIG.