阅读说明：本技术 用于双缸同步负载侧向力试验台的液压系统 (Hydraulic system for double-cylinder synchronous load lateral force test bed ) 是由 王伟伟 刘庆教 李小明 李永奇 张义春 于 2020-05-07 设计创作，主要内容包括：本发明公布一种用于双缸同步负载侧向力试验台的液压系统,属于液压缸性能检测技术领域。柱塞泵出油口连接第一溢流阀、第一换向阀、第二换向阀、第三换向阀、压力传感器；第一换向阀连接第二溢流阀；第二换向阀连接第一被试油缸；第一被试油缸活塞杆连接第一位移传感器；第三换向阀连接第二被试油缸第二被试油缸活塞杆连接第二位移传感器；齿轮泵出油口连接第三溢流阀和第四换向阀；第四换向阀连接加载油缸；加载油缸活塞杆连接第三位移传感器。本发明通过被试油缸二次压力调节提高压力控制精度,侧向载荷施加精准；结构简单,成本较低,兼容性高,适用于目前大部分有同步要求且存在较大侧向载荷工况的油缸试验台。(The invention discloses a hydraulic system for a double-cylinder synchronous load lateral force test bed, and belongs to the technical field of hydraulic cylinder performance detection. An oil outlet of the plunger pump is connected with a first overflow valve, a first reversing valve, a second reversing valve, a third reversing valve and a pressure sensor; the first reversing valve is connected with the second overflow valve; the second reversing valve is connected with the first tested oil cylinder; the piston rod of the first tested oil cylinder is connected with a first displacement sensor; the third reversing valve is connected with a second tested oil cylinder, and a second tested oil cylinder piston rod is connected with a second displacement sensor; an oil outlet of the gear pump is connected with a third overflow valve and a fourth reversing valve; the fourth reversing valve is connected with the loading oil cylinder; and a piston rod of the loading oil cylinder is connected with a third displacement sensor. The invention improves the pressure control precision through the secondary pressure adjustment of the tested oil cylinder, and the side load is applied accurately; the oil cylinder test bed has the advantages of simple structure, lower cost and high compatibility, and is suitable for most oil cylinder test beds with synchronous requirements and larger lateral load working conditions at present.)

1. A hydraulic system for a double-cylinder synchronous load lateral force test bed comprises an oil tank (1) and a quantitative duplex pump (4), wherein the quantitative duplex pump (4) comprises a plunger pump (4.1) for sucking oil from the oil tank (1) and a gear pump (4.2);

the method is characterized in that:

an oil outlet of the plunger pump (4.1) is connected with a first overflow valve (5.1), a first reversing valve (6), a second reversing valve (7.1), a third reversing valve (7.2) and a pressure sensor (16);

the first reversing valve (6) is connected with a second overflow valve (5.2);

the second reversing valve (7.1) is respectively connected with a rod cavity and a rodless cavity of the first tested oil cylinder (10.1); the rodless cavity of the first tested oil cylinder (10.1) is connected with a first flow meter (8.1), and the first flow meter (8.1) is connected with a first flow sensor (17.1); a piston rod of the first tested oil cylinder (10.1) is connected with a first displacement sensor (18.1);

the third reversing valve (7.2) is respectively connected with a rod cavity and a rodless cavity of the second tested oil cylinder (10.2); a rodless cavity of the second tested oil cylinder (10.2) is connected with a second flow meter (8.2), and the second flow meter (8.2) is connected with a second flow sensor (17.2); a piston rod of the second tested oil cylinder (10.2) is connected with a second displacement sensor (18.2);

an oil outlet of the gear pump (4.2) is connected with a third overflow valve (5.3) and a fourth reversing valve (13); the fourth reversing valve (13) is respectively connected with a rod cavity and a rodless cavity of the loading oil cylinder (15); a one-way throttle valve (14) is installed in a rod cavity oil way of the loading oil cylinder (15), and a piston rod of the loading oil cylinder (15) is connected with a third displacement sensor (18.3).

2. The hydraulic system for a dual cylinder synchronous load lateral force test stand of claim 1, wherein: an air filter (19), a liquid level liquid thermometer (20) and a stop valve (21) are arranged on the oil tank (1); an oil return oil filter (11) and a cooler (12) are arranged in an oil return oil path of the oil tank (1); and an oil suction filter (2) is arranged in an oil path from an oil suction port of the plunger pump (4.1) and the gear pump (4.2) to the oil tank (1).

3. The hydraulic system for a dual cylinder synchronous load lateral force test stand of claim 1, wherein: the second reversing valve (7.1) is respectively connected with a rod cavity and a rodless cavity of the first tested oil cylinder (10.1) through a first quick-change connector (9.1) and a second quick-change connector (9.2).

4. The hydraulic system for a dual cylinder synchronous load lateral force test stand of claim 1, wherein: and the third reversing valve (7.2) is respectively connected with a rod cavity and a rodless cavity of the second tested oil cylinder (10.2) through a third quick-change connector (9.3) and a fourth quick-change connector (9.4).

5. The hydraulic system for a dual cylinder synchronous load lateral force test stand of claim 1, wherein: and the fourth reversing valve (13) is respectively connected with a rod cavity and a rodless cavity of the loading oil cylinder (15) through a sixth quick-change connector (9.6) and a fifth quick-change connector (9.5).

6. The hydraulic system for a dual cylinder synchronous load lateral force test stand of claim 1, wherein: the first overflow valve (5.1), the second overflow valve (5.2) and the third overflow valve (5.3) are all electric proportional overflow valves.

7. The hydraulic system for a dual cylinder synchronous load lateral force test stand of claim 1, wherein: the one-way throttle valve (14) is opened when oil enters a rodless cavity of the loading oil cylinder (15), and throttling is not performed; when the load oil cylinder (15) is in rodless cavity oil return state, the one-way throttle valve (14) is closed to throttle.

8. The hydraulic system for a dual cylinder synchronous load lateral force test stand of claim 1, wherein: the middle position of the fourth reversing valve (13) is in a normally open state, and hydraulic oil discharged by the gear pump (4.2) directly returns to the oil tank (1) in the middle position state of the fourth reversing valve (13).

Technical Field

The invention relates to the technical field of hydraulic cylinder performance detection, in particular to a hydraulic system for a double-cylinder synchronous load lateral force test bed.

Background

The hydraulic cylinders are used as key executing elements in engineering machinery, some hydraulic cylinders need to bear larger lateral loads according to different installation positions and exerted functions, and some hydraulic cylinders not only need to bear larger lateral loads, but also need to keep synchronous, namely the loading force and the stroke are kept consistent when a plurality of hydraulic cylinders simultaneously execute one action, and the main thrust cylinder of a common shield machine is used. The lateral load is easy to cause bending, abnormal abrasion and fracture of parts of the hydraulic cylinder, and the reliability and the service life of the product are influenced; for the hydraulic cylinders with multi-cylinder synchronization requirements, if the phenomenon of asynchronization occurs, part of the hydraulic cylinders are overloaded, hinge points are damaged if the phenomenon is light, and cylinder explosion occurs if the phenomenon is heavy, so that great loss is brought to a host user.

The working conditions of large load and high side load provide higher requirements for the reliability of hydraulic cylinder products, and the working condition simulation test is necessary before new products are applied. For example, the chinese patent discloses a double-cylinder synchronous radial load test device (CN 109083886A), comprising an installation rack; two tested oil cylinders which are arranged oppositely in parallel are fixed on the mounting rack through a fixing device; a loading device is connected between the piston rod ends of the two tested cylinders; and the piston rod ends of the two tested cylinders are connected with a synchronous detection device.

Although the above technology discloses a double-cylinder synchronous radial load test device, a hydraulic system of a tested oil cylinder and a loading device is not disclosed therein. The existing common loading hydraulic system is generally low in control precision and inaccurate in load application, and finally results in test data distortion.

Disclosure of Invention

In order to solve the technical problems, the invention provides the hydraulic system for the double-cylinder synchronous load lateral force test bed, which has high control precision and accurate load application.

The invention is realized by the following technical scheme: a hydraulic system for a double-cylinder synchronous load lateral force test bed comprises an oil tank and a quantitative dual pump, wherein the quantitative dual pump comprises a plunger pump and a gear pump which absorb oil from the oil tank; an oil outlet of the plunger pump is connected with a first overflow valve, a first reversing valve, a second reversing valve, a third reversing valve and a pressure sensor; the first reversing valve is connected with a second overflow valve; the second reversing valve is respectively connected with a rod cavity and a rodless cavity of the first tested oil cylinder; the rodless cavity of the first tested oil cylinder is connected with a first flow meter, and the first flow meter is connected with a first flow sensor; a piston rod of the first tested oil cylinder is connected with a first displacement sensor; the third reversing valve is respectively connected with a rod cavity and a rodless cavity of the second tested oil cylinder; the rodless cavity of the second tested oil cylinder is connected with a second flow meter, and the second flow meter is connected with a second flow sensor; a piston rod of the second tested oil cylinder is connected with a second displacement sensor; an oil outlet of the gear pump is connected with a third overflow valve and a fourth reversing valve; the fourth reversing valve is respectively connected with a rod cavity and a rodless cavity of the loading oil cylinder; and a one-way throttle valve is installed in an oil way of a rod cavity of the loading oil cylinder, and a piston rod of the loading oil cylinder is connected with a third displacement sensor.

It further comprises the following steps: an air filter, a liquid level liquid thermometer and a stop valve are arranged on the oil tank; an oil return filter and a cooler are arranged in an oil return path of the oil tank; and an oil suction oil filter is arranged in an oil path from the oil suction port of the plunger pump and the gear pump to the oil tank.

And the second reversing valve is respectively connected with a rod cavity and a rodless cavity of the first tested oil cylinder through a first quick-change connector and a second quick-change connector.

And the third reversing valve is respectively connected with a rod cavity and a rodless cavity of the second tested oil cylinder through a third quick-change connector and a fourth quick-change connector.

And the fourth reversing valve is respectively connected with a rod cavity and a rodless cavity of the loading oil cylinder through a sixth quick-change connector and a fifth quick-change connector.

The first overflow valve, the second overflow valve and the third overflow valve are all electric proportional overflow valves.

The one-way throttle valve is opened when oil enters the rodless cavity of the loading oil cylinder, and throttling is not performed; when the one-way throttle valve returns oil in the rodless cavity of the loading oil cylinder, the one-way valve is closed to throttle.

And the middle position of the fourth reversing valve is in a normally open state, and hydraulic oil discharged by the gear pump directly returns to the oil tank under the middle position state of the fourth reversing valve.

Compared with the prior art, the invention has the beneficial effects that: the pressure control precision is improved through secondary pressure adjustment of the tested oil cylinder, and the side load is applied accurately; simple structure, the cost is lower, and is compatible high, is applicable to most at present and has synchronous requirement and have the hydro-cylinder test bench of great side load operating mode, provides hydraulic drive for shield constructs owner and pushes away hydro-cylinder, crane leg hydro-cylinder etc. and have side load operating mode product when imitating the operating mode test for the shield.

Drawings

FIG. 1 is a hydraulic system diagram of an embodiment of the present invention;

in the figure: an oil tank 1, an oil absorption oil filter 2, a variable frequency motor 3, a quantitative dual pump 4, a plunger pump 4.1, a gear pump 4.2, a first overflow valve 5.1, a second overflow valve 5.2, a third overflow valve 5.3, a first reversing valve 6, a second reversing valve 7.1, a third reversing valve 7.2, a first flowmeter 8.1, a second flowmeter 8.2, a first quick-change connector 9.1, a second quick-change connector 9.2, a third quick-change connector 9.3 and a fourth quick-change connector 9.4, the hydraulic test system comprises a fifth quick-change connector 9.5, a sixth quick-change connector 9.6, a first tested oil cylinder 10.1, a second tested oil cylinder 10.2, a return oil filter 11, a cooler 12, a fourth reversing valve 13, a one-way throttle valve 14, a loading oil cylinder 15, a pressure sensor 16, a first flow sensor 17.1, a second flow sensor 17.2, a first displacement sensor 18.1, a second displacement sensor 18.2, a third displacement sensor 18.3, an air filter 19, a liquid level liquid thermometer 20 and a stop valve 21.

Detailed Description

The following is a specific embodiment of the present invention, which will be further described with reference to the accompanying drawings.

Referring to fig. 1, a hydraulic system for a double-cylinder synchronous load lateral force test bed is disclosed, wherein a quantitative dual pump 4 comprises a plunger pump 4.1 sucking oil from an oil tank 1 and a gear pump 4.2. The oil tank 1 is provided with an air cleaner 19, a liquid level thermometer 20 and a stop valve 21. An oil return filter 11 and a cooler 12 are arranged in an oil return path of the oil tank 1; an oil suction filter 2 is arranged in an oil path from an oil suction port of the plunger pump 4.1 and the gear pump 4.2 to the oil tank 1.

An oil outlet of the plunger pump 4.1 is connected with a first overflow valve 5.1, a first reversing valve 6, a second reversing valve 7.1, a third reversing valve 7.2 and a pressure sensor 16;

the first reversing valve 6 is connected with a second overflow valve 5.2;

the second reversing valve 7.1 is connected with a rod cavity and a rodless cavity of the first tested oil cylinder 10.1 through a first quick-change connector 9.1 and a second quick-change connector 9.2 respectively. The rodless cavity of the first tested oil cylinder 10.1 is connected with a first flow meter 8.1, and the first flow meter 8.1 is connected with a first flow sensor 17.1; a piston rod of the first tested oil cylinder 10.1 is connected with a first displacement sensor 18.1;

the third reversing valve 7.2 is connected with a rod cavity and a rodless cavity of the second tested oil cylinder 10.2 through a third quick-change connector 9.3 and a fourth quick-change connector 9.4 respectively. The rodless cavity of the second tested oil cylinder 10.2 is connected with a second flow meter 8.2, and the second flow meter 8.2 is connected with a second flow sensor 17.2; a second displacement sensor 18.2 is connected to the piston rod of the second cylinder 10.2.

In this embodiment, the first quick-change coupler 9.1, the second quick-change coupler 9.2, the third quick-change coupler 9.3, and the fourth quick-change coupler 9.4 are provided, so that the cylinder changing efficiency of the first tested oil cylinder 10.1 and the second tested oil cylinder 10.2 and the cleanliness of the field environment can be improved.

In the embodiment, the oil pressure of the rodless cavity of the first tested oil cylinder 10.1 is detected by arranging a first flow meter 8.1 and a first pressure sensor 17.1; the oil pressure of a rodless cavity of a second tested oil cylinder 10.2 is detected by arranging a second flow meter 8.2 and a second pressure sensor 17.2; so as to judge whether the friction force applied to the first tested oil cylinder 10.1 and the second tested oil cylinder 10.2 is consistent. The displacement of the piston rods of the first tested oil cylinder 10.1 and the second tested oil cylinder 10.2 is respectively detected by arranging the first displacement sensor 18.1 and the second displacement sensor 18.2, so that the synchronous precision of the double-cylinder operation is judged.

An oil outlet of the gear pump 4.2 is connected with a third overflow valve 5.3 and a fourth reversing valve 13;

the fourth reversing valve 13 is respectively connected with the rod cavity and the rodless cavity of the loading oil cylinder 15 through a sixth quick-change connector 9.6 and a fifth quick-change connector 9.5, so that the cylinder changing efficiency of the loading oil cylinder 15 and the cleanliness of a field environment can be improved. A one-way throttle valve 14 is installed in an oil way of a rod cavity of the loading oil cylinder 15, and a piston rod of the loading oil cylinder 15 is connected with a third displacement sensor 18.3. The third displacement sensor 18.3 is used for detecting the displacement of the piston rod of the loading cylinder 15 so as to improve the application accuracy of the side load.

The middle position of the fourth reversing valve 13 is in a normally open state, and hydraulic oil discharged by the gear pump 4.2 in the middle position state of the fourth reversing valve 13 directly returns to the oil tank 1. Therefore, under the condition that the fourth reversing valve 13 does not act, the hydraulic oil discharged by the gear pump 4.2 directly returns to the oil tank through the cooler 12 and the return oil filter 11 so as to adapt to installation of the first tested oil cylinder 10.1 and the second tested oil cylinder 10.2 and other no-side-load working condition tests such as lowest starting pressure and the like.

The one-way throttle valve 14 is opened when oil enters a rodless cavity of the loading oil cylinder 15, and throttling is not performed; when the loading oil cylinder 15 returns oil without a rod cavity, the one-way throttle valve 14 is closed to throttle and control the extension speed of the loading oil cylinder 15. The one-way throttle valve 14 improves the accuracy of applying the lateral load on one hand, and increases the pressure relief time during pressure relief on the other hand, so that the lateral load is slowly released, and the impact of piston rods of the first tested oil cylinder 10.1 and the second tested oil cylinder 10.2 is reduced.

Preferably: the first overflow valve 5.1, the second overflow valve 5.2 and the third overflow valve 5.3 are all electric proportional overflow valves, and the control precision is high.

The working principle is as follows:

the plunger pump 4.1 is used as a power source of the first tested oil cylinder 10.1 and the second tested oil cylinder 10.2, the variable frequency motor 3 provides power to suck out and discharge high-pressure hydraulic oil from the oil tank 1, the pressure of the hydraulic oil is regulated by the first overflow valve 5.1 and the second overflow valve 5.2, the tested hydraulic cylinders 10.1 and 10.2 are respectively driven by the second reversing valve 7.1 and the third reversing valve 7.2, and the hydraulic oil returns to the oil tank 1 through the cooler 12 and the return oil filter 11 to form an internal circulation;

the high-pressure hydraulic oil discharged by the plunger pump 4.1 is first pressure-regulated by the first overflow valve 5.1 and transmits a pressure signal to the pressure sensor 16. According to the feedback signal of the pressure sensor 16, the first reversing valve 6 and the second overflow valve 5.2 perform secondary pressure regulation so as to improve the pressure control accuracy of the first tested cylinder 10.1 and the second tested cylinder 10.2.

The gear pump 4.2 is used as a power source of the loading oil cylinder 15, the output force of the plunger pump 4.1 provides power to suck and discharge high-pressure hydraulic oil from the oil tank 1, a third overflow valve 5.3 of the hydraulic oil is used for pressure regulation, the loading cylinder 15 is driven by a fourth reversing valve 13 and a one-way throttle valve 14, and the hydraulic oil returns to the oil tank 1 through a cooler 12 and an oil return filter 11 to form internal circulation;

the loading oil cylinder 15 is arranged between the first tested oil cylinder 10.1 and the second tested oil cylinder 10.2, and when a piston rod of the loading oil cylinder 15 retracts, a direction-finding load is provided for the tested oil cylinders 10.1 and 10.2. The hydraulic oil discharged by the gear pump 4.2 is pressure-regulated via an electric proportional relief valve 5.3 to precisely control the output load of the loading cylinder 15.