Multifunctional pump source of hydraulic valve

Abstract

The utility model discloses a multifunctional pump source of a hydraulic valve, which comprises two two-position three-way electromagnetic valves, a proportional overflow valve, a safety overflow valve and a pilot proportional direction valve, and is characterized by further comprising an Ls electrical unauthorized load sensitive pump, and a fixed-frequency motor matched with the Ls electrical unauthorized load sensitive pump; an outlet of the Ls electrical unauthorized load sensitive pump is connected with the pilot proportional direction valve; a C port of the first two-position three-way electromagnetic valve is connected with an Ls port of the Ls electrical unauthorized load sensitive pump, an A port is connected to an outlet of the pilot proportional direction valve, and a B port is connected with an Ls feedback port of the tested valve; a port C of the second two-position three-way solenoid valve is connected with a port P1 of the Ls electrical unauthorized load sensitive pump, a port A is connected with an inlet of the pilot proportional direction valve, and a port B is connected with a port P of the tested valve. The test bench can be compatible with tests of various hydraulic valves such as an overflow valve, the adjustment precision is high, and the influence of pipeline pressure loss on a test result is eliminated.

Description

Technical Field

[0001] This utility model relates to hydraulic transmission pump source technology, and in particular to a multi-functional pump source for hydraulic valves. Background Technology

[0002] Hydraulic valve test benches handle a wide variety of hydraulic valves, including pressure valves and multi-way valves. Typical factory tests include steady-state pressure-flow characteristic tests, pressure loss tests, flow fretting tests, output flow-input signal characteristic tests under constant pressure drop, and internal leakage tests. For steady-state pressure-flow characteristic and pressure loss tests, the pump source needs to operate in electro-proportional variable pump mode and be able to precisely adjust the flow rate. For output flow-input signal characteristic tests under constant pressure drop, the pump source needs to operate in load-sensitive variable pump mode. For internal leakage detection tests, the pump source needs to operate in constant pressure variable pump mode and be able to remotely adjust the constant pressure. Given these requirements, the pump source of the hydraulic valve test bench needs to have extremely high flexibility to accommodate various test items for different types of hydraulic valves.

[0003] Due to varying operating conditions, the working pressure differential of load-sensitive multi-way valves will differ. When conducting output flow-input signal characteristic tests under constant pressure drop, the pump source pressure differential needs to be adjusted according to the multi-way valve's working pressure differential. In existing technologies, the pump's flow compensation valve can only be manually adjusted, and the considerable distance between the power pump and the multi-way valve under test directly affects the test results.

[0004] Meanwhile, when conducting tests such as hydraulic valve pressure loss detection, precise and rapid control of the pump source flow is required. In existing technologies, the flow regulation method using a variable frequency motor to control a load-sensitive variable pump suffers from low control accuracy and slow response due to the low-speed performance of the load-sensitive variable pump and the acceleration / deceleration time of the frequency converter. Currently, there is no energy source for the test bench that can comprehensively meet the above requirements and achieve automatic and rapid switching of operating modes. Summary of the Invention

[0005] The purpose of this invention is to solve the above problems by providing a multi-functional pump source for hydraulic valves and its control and switching method, which has the characteristics of enabling the test bench pump source to be basically compatible with the power supply of various hydraulic valves.

[0006] The above-mentioned technical problems of this utility model are mainly solved by the following technical solution: a multi-functional pump source for hydraulic valves, including a first two-position three-way solenoid valve, a second two-position three-way solenoid valve, a proportional relief valve, a safety relief valve, and a pilot proportional directional valve for connecting the outlet to a test bench system, characterized in that it also includes an Ls electrically overload sensitive pump, and a fixed frequency motor is provided with the Ls electrically overload sensitive pump.

[0007] The Ls electrical overload sensitive pump has its inlet connected to the oil tank and its outlet connected to the pilot proportional directional valve.

[0008] The first two-position three-way solenoid valve has its C port connected to the Ls port of the Ls electrically overload sensitive pump, and its A port connected to the outlet of the pilot proportional directional valve, and its B port connected to the feedback port of the valve under test, Ls.

[0009] The second two-position three-way solenoid valve has port C connected to port P1 of the Ls electrical overload sensitive pump, port A connected to the inlet of the pilot proportional directional valve, and port B connected to port P of the valve under test.

[0010] In the aforementioned multi-functional pump source of hydraulic valve, as a preferred embodiment, the Ls electrically overriding load sensitive pump integrates an Ls electrically overriding control valve and a load sensitive compensation valve; the Ls electrically overriding control valve is a proportional pressure reducing valve; the Ls electrically overriding control valve is used to adjust the working differential pressure of the Ls electrically overriding load sensitive pump.

[0011] In the aforementioned multi-functional hydraulic valve pump source, preferably, the safety relief valve is installed at the outlet of the Ls electrical overload sensitive pump, and a flow switch is connected to the outlet of the safety relief valve; the pressure of the safety relief valve is higher than the rated working pressure of the test bench.

[0012] In the aforementioned multi-functional hydraulic valve pump source, preferably, the proportional relief valve is located at the Ls port of the Ls electrically overload sensitive pump, and the rated pressure of the proportional relief valve is lower than the set pressure of the safety relief valve.

[0013] In the aforementioned multi-functional pump source for hydraulic valves, preferably, the first two-position three-way solenoid valve and the second two-position three-way solenoid valve are bidirectional flow-free zero-leakage solenoid valves.

[0014] This technical solution utilizes an LS electrically overload sensitive pump design, combined with a pilot-operated proportional directional valve and a two-position three-way solenoid valve, to alter the pump source's output flow rate. Feedback is provided by the P port and LS port of the valve under test. A safety relief valve with a flow switch is included to protect the LS electrically overload controlled sensitive pump; when a signal is detected, the program controls the fixed-frequency motor to stop.

[0015] Compared with the prior art, the beneficial effects of this utility model are:

[0016] (1) During the test, the constant pressure electric proportional variable pump working mode and the constant pressure load sensitive variable pump working mode can be switched; thus enabling the test bench to be compatible with the testing of various hydraulic valves such as relief valve, pressure reducing valve, proportional directional valve, and multi-way valve, and to provide a simple and efficient power source for the factory test of hydraulic valves.

[0017] (2) When the pump source is working in the hydraulic electric proportional variable pump mode, the output flow of the pump source can be infinitely adjusted from zero flow to maximum flow by adjusting the pilot proportional directional valve, and the adjustment accuracy is high and the response is fast.

[0018] (3) The Ls electrical overriding control load-sensitive variable pump setting can easily adjust the differential pressure of the load-sensitive variable pump when it is necessary to change the differential pressure. This solves the problem that the working differential pressure of the hydraulic valve is not unique and different products need to adjust the spring of the constant flow valve of the load-sensitive pump, which is inconvenient to adjust.

[0019] (4) Connect the P1 port of the Ls electrical overload sensitive pump to the P port of the valve under test to eliminate the influence of pipeline pressure loss on the test results. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the hydraulic principle of this utility model.

[0021] In the diagram: 1-Ls Electrically Overriding Load Sensitive Pump; 2-Proportional Relief Valve; 3-First Two-Position Three-Way Solenoid Valve; 4-Pilot Proportional Directional Valve; 5-Second Two-Position Three-Way Solenoid Valve; 6-Safety Relief Valve; 7-Flow Switch; 8-Fixed Frequency Motor; 9-Ls Electrically Overriding Control Valve; 10-Load Sensitive Compensation Valve. Detailed Implementation

[0022] The technical solution of this utility model will be further described in detail below through embodiments and in conjunction with the accompanying drawings.

[0023] like Figure 1 As shown, this embodiment of a hydraulic valve multi-functional pump source includes a first two-position three-way solenoid valve 3, a second two-position three-way solenoid valve 5, a proportional relief valve 2, a safety relief valve 6, and a pilot proportional directional valve 4 connected to the test bench system at the outlet. It also includes an Ls electrical overload sensitive pump 1, and a fixed frequency motor 8 is provided with the Ls electrical overload sensitive pump.

[0024] The Ls electrically overload sensitive pump 1 includes a hydraulic pump and integrates an Ls electrically overload control valve 9 and a load-sensing compensation valve 10; wherein the Ls electrically overload control valve is a proportional pressure reducing valve. The Ls electrically overload control valve is used to regulate the working differential pressure of the Ls electrically overload sensitive pump.

[0025] The first two-position three-way solenoid valve 3 and the second two-position three-way solenoid valve 5 are bidirectional, zero-leakage solenoid valves.

[0026] The inlet of the Ls electrical overload sensitive pump 1 is connected to the oil tank, and the outlet is connected to the pilot proportional directional valve 4. Simultaneously, a safety relief valve 6 is also connected to the outlet of the Ls electrical overload sensitive pump 1. A flow switch 7 is connected to the outlet of the safety relief valve 6. The function of the safety relief valve 6 is to protect the Ls electrical overload sensitive pump 1. The pressure of the safety relief valve 6 is higher than the rated operating pressure of the test bench.

[0027] The C port of the first two-position three-way solenoid valve 3 is connected to the Ls port of the Ls electrically overload sensitive pump 1, and the A port of the first two-position three-way solenoid valve 3 is connected to the outlet of the pilot proportional directional valve 4, and the B port is connected to the Ls feedback port of the valve under test; the C port of the second two-position three-way solenoid valve 5 is connected to the P1 port of the Ls electrically overload sensitive pump 1, the A port is connected to the inlet of the pilot proportional directional valve 4, and the B port is connected to the P port of the valve under test; the output flow of the hydraulic valve multi-functional pump source can be adjusted accurately and quickly.

[0028] The proportional relief valve 2 is located at the Ls port of the Ls electrically overload sensitive pump 1 and is used to adjust the constant pressure point of the pump source. The rated pressure of the proportional relief valve 2 is lower than the set pressure of the safety relief valve 6.

[0029] This embodiment of the multi-functional pump source for hydraulic valves is mainly used in the factory test bench for hydraulic valves. It can adapt to test items such as steady-state pressure-flow characteristic test, pressure loss test (for electro-proportional variable pump system), internal leakage detection and other test items (for constant pressure variable pump system), as well as output flow-input signal characteristic test under constant pressure drop, flow micro-motion test and other test items (for load-sensitive variable pump system).

[0030] Principles and applications:

[0031] The control and switching method for the multi-functional pump source of the hydraulic valve in this embodiment includes the following:

[0032] 1. When testing steady-state pressure-flow characteristic test and pressure loss test, the pump source is switched to the electric proportional variable pump working mode, so that the first two-position three-way solenoid valve 3 and the second two-position three-way solenoid valve 5 are energized. At this time, the constant pressure point of the pump source can be adjusted through the proportional relief valve 2, and the flow rate of the pump source can be adjusted through the pilot proportional directional valve 4.

[0033] 2. When the test items are constant pressure drop output flow-input signal characteristic test and multi-way valve flow micro-motion test, the pump source is switched to load-sensitive constant pressure variable pump mode, the first two-position three-way solenoid valve 3 and the second two-position three-way solenoid valve 5 are de-energized, the Ls port of the load-sensitive pump 1 is connected to the Ls port of the multi-way valve, the P1 port is connected to the P port of the multi-way valve, and the pilot proportional directional valve 4 is fully open.

[0034] 3. When the working pressure difference of the valve under test is inconsistent with the initial pressure difference of the pump source, the Ls electrical overriding control valve on the LS electrical overriding control load sensitive pump 1 can be adjusted to make the pressure difference reach the working pressure difference of the valve under test.

[0035] IV. When testing internal leakage and pressure resistance tests, the pump source needs to operate in constant pressure variable pump mode to energize the first two-position three-way solenoid valve and the second two-position three-way solenoid valve, and fully open the pilot proportional directional valve.

[0036] Furthermore, when the pump source is operating in the Ls electrical overload sensitive pump 1 mode, and the first two-position three-way solenoid valve 3 and the second two-position three-way solenoid valve 5 are de-energized, the P port of the valve under test is connected to the P1 port of the Ls electrical overload sensitive pump 1 to eliminate the influence of pipeline pressure loss on the test results.

[0037] In this embodiment, without stopping the fixed-frequency motor 8, the pump source can be seamlessly switched between constant pressure variable pump mode, electro-proportional variable pump mode and load-sensitive variable pump mode according to different test items, and accurately and quickly provide the flow rate and pressure required for the test.

[0038] The above embodiments are illustrative of the present invention and not intended to limit the present invention. The described embodiments are merely some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present invention.

Claims

1. A multi-functional hydraulic valve pump source, comprising a first two-position three-way solenoid valve (3), a second two-position three-way solenoid valve (5), a proportional relief valve (2), a safety relief valve (6), and a pilot proportional directional valve (4) for connecting the outlet to a test bench system, characterized in that... It also includes an Ls electrical overload sensitive pump (1), and a fixed frequency motor (8) is provided with the Ls electrical overload sensitive pump. The Ls electrical overload sensitive pump has its inlet connected to the oil tank and its outlet connected to the pilot proportional directional valve. The first two-position three-way solenoid valve has its C port connected to the Ls port of the Ls electrically overload sensitive pump, and its A port is connected to the outlet of the pilot proportional directional valve, and its B port is connected to the feedback port of the valve under test Ls. The second two-position three-way solenoid valve has port C connected to port P1 of the Ls electrical overload sensitive pump, port A connected to the inlet of the pilot proportional directional valve, and port B connected to port P of the valve under test.

2. The multi-functional pump source for hydraulic valves according to claim 1, characterized in that, The Ls electrical overload sensitive pump (1) integrates an Ls electrical overload control valve (9) and a load sensitive compensation valve (10); the Ls electrical overload control valve is a proportional pressure reducing valve; the Ls electrical overload control valve is used to adjust the working pressure difference of the Ls electrical overload sensitive pump.

3. The multi-functional pump source for hydraulic valves according to claim 1, characterized in that, The safety relief valve (6) is located at the outlet of the Ls electrical overload sensitive pump (1), and a flow switch (7) is connected to the outlet of the safety relief valve; the pressure of the safety relief valve is higher than the rated working pressure of the test bench.

4. The multi-functional pump source for hydraulic valves according to claim 3, characterized in that, The proportional relief valve (2) is located at the Ls port of the Ls electrical overload sensitive pump (1), and the rated pressure of the proportional relief valve is lower than the set pressure of the safety relief valve (6).

5. The multi-functional pump source for hydraulic valves according to claim 1, characterized in that, The first two-position three-way solenoid valve (3) and the second two-position three-way solenoid valve (5) are zero-leakage solenoid valves capable of bidirectional flow.

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