A solenoid valve negative pressure test system, method and automatic test device

Abstract

This invention discloses a solenoid valve negative pressure testing system, method, and automatic testing device, comprising a vacuum pump, a vacuum regulating valve, a two-way solenoid valve, a pressure controller, a pressure transmitter, and a gas compensator connected in sequence. The output end of the gas compensator is connected to a reversing solenoid valve assembly, which includes two three-way solenoid valves for connecting to the solenoid valve under test. One three-way solenoid valve has its NC terminal connected to air and its NO terminal connected in series with a gas compensation container. The other three-way solenoid valve has its NO terminal connected to air and its NC terminal connected in series with the gas compensation container. The COM terminals of the two three-way solenoid valves are respectively connected to the input and output terminals of the solenoid valve under test. This improves testing efficiency and provides an automatic reversing testing function, making it suitable for negative pressure testing of various solenoid valves.

Description

Technical Field

[0001] This invention belongs to the field of electromagnetic valve testing, and relates to an electromagnetic valve negative pressure testing system, method and automatic testing device. Background Technology

[0002] Currently, there are various methods for testing the negative pressure of small solenoid valves on the market, resulting in low testing efficiency and large errors in manual testing. Existing solenoid valve negative pressure testing systems do not have automatic reversing testing functions and can only be used for negative pressure testing of one type of solenoid valve, making them poorly applicable. Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings of the prior art and provide a solenoid valve negative pressure testing system, method and automatic testing device, which improves testing efficiency and has an automatic reversing testing function, and is suitable for negative pressure testing of various solenoid valves.

[0004] To achieve the above objectives, the present invention employs the following technical solution:

[0005] A solenoid valve negative pressure testing system includes a vacuum pump, a vacuum regulating valve, a two-way solenoid valve, a pressure controller, a pressure transmitter, and a gas compensator connected in sequence.

[0006] The output of the gas compensator is connected to a reversing solenoid valve assembly, which includes two three-way solenoid valves for connecting to the solenoid valve under test. One of the three-way solenoid valves has its NC terminal connected to air and its NO terminal connected in series with the gas compensation container. The other three-way solenoid valve has its NO terminal connected to air and its NC terminal connected in series with the gas compensation container. The COM terminals of the two three-way solenoid valves are connected to the input and output terminals of the solenoid valve under test, respectively.

[0007] Preferably, the gas compensation container is a syringe.

[0008] Preferably, the number of two-way solenoid valves, pressure controllers, pressure transmitters, gas compensators, and reversing solenoid valve groups are all multiple and the number is the same.

[0009] Furthermore, the vacuum regulating valve is connected to a multi-way distributor, and each of the multi-way distributor's multiple output terminals is connected to a two-way solenoid valve.

[0010] A method for testing the negative pressure of a solenoid valve based on the system involves performing a negative pressure test on the input end of the solenoid valve under test: a vacuum pump and a two-way solenoid valve are simultaneously energized, while two three-way solenoid valves and the solenoid valve under test are not working. After the negative pressure is drawn to the target value, the vacuum pump and the two-way solenoid valve are simultaneously shut off. The pressure controller uploads the final reading to determine whether the solenoid valve under test is leaking. After the determination is completed, the solenoid valve under test is energized to release the gas pressure in the pipeline, and all components are shut off.

[0011] A negative pressure test is performed on the output end of the solenoid valve under test: the vacuum pump, the two-way solenoid valve, and the two three-way solenoid valves are energized simultaneously, the solenoid valve under test is not working, and after the negative pressure is drawn to the target value, the vacuum pump and the two-way solenoid valve are turned off simultaneously, while the two three-way solenoid valves are continuously energized. The pressure controller uploads the final reading to determine whether the solenoid valve under test is leaking. After the determination is completed, the solenoid valve under test is energized, and the three-way solenoid valve connected to the input end of the solenoid valve under test is de-energized to release the gas pressure in the pipeline.

[0012] An automatic testing device for negative pressure of a solenoid valve includes a frame assembly, a clamping fixture, a control system, and the solenoid valve negative pressure testing system.

[0013] The rack assembly is hollow inside, and the top surface of the rack assembly is a platform; the clamping fixture is located in the center of the platform of the rack assembly and is used to clamp the solenoid valve to be tested.

[0014] The control system is mounted on the frame assembly and includes a host computer and an electrical system. The host computer is interconnected with each component of the solenoid valve negative pressure testing system, and the electrical system is electrically connected to both the host computer and the solenoid valve negative pressure testing system. The solenoid valve negative pressure testing system is located inside the frame assembly, and the reversing solenoid valve group is connected to the bottom of the clamping fixture.

[0015] Preferably, the frame assembly is provided with a compensator fixing assembly, which includes a clamp plate, a clamp plate, a clamp plate, and a clamp plate. The clamp plates are vertically connected and the clamp plates are fixed on the frame assembly. The frame assembly has multiple sets of mounting holes on the upper and lower sides of the clamp plates. The clamp plates are connected to the movable end of the gas compensation container. The clamp plates are vertically connected and the clamp plates are fixed on the frame assembly. The clamp plates are connected to the cavity end of the gas compensation container.

[0016] Preferably, the clamping fixture includes an upper cover plate, a lower cover plate, and a rubber seal. The upper cover plate and the lower cover plate have mounting holes in corresponding areas. The rubber seal is connected between the upper cover plate and the lower cover plate and is interference-fitted with the mounting holes. The rubber seal has two or three air holes.

[0017] Preferably, the electrical system mainly includes an external power supply module, a relay group, a main equipment switch, an emergency stop button, and a test start button. The output of the external power supply module is connected to the input of the relay group. The output of the relay group is electrically connected to the host computer and the solenoid valve negative pressure test system, respectively. The test start button is connected to the input of the host computer. The main equipment switch, the emergency stop button, and the main equipment switch are all located between the external power supply module and the relay group.

[0018] Preferably, the rack assembly is equipped with tri-color lights and indicator lights, and the input terminals of the tri-color lights and indicator lights are all connected to the output terminals of the host computer.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] The system described in this invention consists of a vacuum pump, a vacuum regulating valve, a two-way solenoid valve, a pressure controller, a pressure transmitter, and a gas compensator connected in sequence. The output end of the gas compensator is connected to two three-way solenoid valves. Under the control of the pressure controller, it has an automatic reversing test function, which improves the test efficiency by about 3 times compared to manual testing. The equipment is highly expandable and can be used not only for testing two-way valves but also for testing three-way valves. Moreover, different models of two-way and three-way valves can be tested on this equipment, making it suitable for negative pressure testing of various solenoid valves.

[0021] The device described in this invention can upgrade the test data from the existing manual reading to automatic reading and judgment of the test results by the system, and automatically store the test data. It has higher test accuracy and reduces human influence factors compared with the existing test methods. It is also scalable and can be improved to meet the test needs of different solenoid valves. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the automatic negative pressure test principle of the solenoid valve of the present invention.

[0023] Figure 2 This is an isometric view (a) of the automatic negative pressure testing device for the electromagnetic valve of the present invention.

[0024] Figure 3 This is an isometric view (b) of the electromagnetic valve negative pressure automatic testing device of the present invention.

[0025] Figure 4 This is a front view of the automatic negative pressure testing device for electromagnetic valves according to the present invention.

[0026] Figure 5 This is a top view (a) of the automatic negative pressure testing device for the electromagnetic valve of the present invention.

[0027] Figure 6 This is a left view of the automatic negative pressure testing device for the electromagnetic valve of the present invention.

[0028] Figure 7 This is a right view of the automatic negative pressure testing device for the electromagnetic valve of the present invention.

[0029] Figure 8 This is a bottom view of the automatic negative pressure testing device for the electromagnetic valve of the present invention.

[0030] Figure 9 This is a rear view (a) of the automatic negative pressure testing device for the electromagnetic valve of the present invention.

[0031] Figure 10 This is a rear view (b) of the electromagnetic valve negative pressure automatic testing device of the present invention.

[0032] Figure 11 This is the main view of the clamping fixture of the present invention.

[0033] Figure 12This is a side view of the clamping fixture of the present invention.

[0034] Figure 13 This is a schematic diagram of the solenoid valve assembly structure of the present invention.

[0035] Figure 14 This is a top view (b) of the automatic negative pressure testing device for the electromagnetic valve of the present invention.

[0036] Figure 15 This is a schematic diagram of the reversing valve assembly structure of the present invention.

[0037] Figure 16 This is an isometric view of the electronic control board of the present invention.

[0038] The components are as follows: 1-Frame assembly; 101-Front baffle; 102-Left side panel; 103-Right side panel; 104-Front panel; 105-Tabletop panel; 106-Top panel; 107-Base plate; 108-Foot; 109-Lower panel; 110-Door panel; 111-Electrical control board; 112-Pressure controller mounting plate; 113-Frame; 2-Clamping fixture; 201-Upper cover plate; 202-Lower cover plate; 203-Rubber seal; 3-Control system; 301-Host computer; 302-Electrical system; 302a-External power supply module; 302b-Relay group; 302c-Tricolor indicator light; 302d-Main switch; 302e-Emergency stop button; 302f-Test start button; 302g-Indicator light; 4-Pneumatic circuit assembly; 401-Vacuum pump; 402-Vacuum... Pressure regulating valve; 403-Pressure controller assembly; 403-01 to 403-10 are pressure controllers 1 to 10; 404-Pressure transmitter assembly; 404-01 to 404-10 are pressure transmitters 1 to 10; 405-Gas compensation container assembly; 405-01 to 405-10 are syringes 1 to 10; 406-Reversing solenoid valve assembly; 406-01 to 406-20 are three-way solenoid valves 1 to 20; 407-Solenoid valve assembly; 407-01 to 407-10 are two-way solenoid valves 1 to 10; 5-Multi-way distributor; 6-Compensator mounting assembly; 601-Clamping plate; 602-Clamping plate; 603-Clamping plate; 604-Clamping plate; 7-Three-way solenoid valve mounting plate; 8-Threaded connector; 9-Solenoid valve mounting plate. Detailed Implementation

[0039] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0040] It should be noted that the terms “front,” “back,” “left,” “right,” “up,” and “down” used in the following description refer to the directions shown in the attached diagram, while the terms “inside” and “outside” refer to the directions toward or away from the geometric center of a specific component, respectively.

[0041] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the specification of this invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0042] like Figure 1 As shown, the solenoid valve negative pressure testing system of the present invention includes a vacuum pump 401, a vacuum regulating valve 402, a two-way solenoid valve, a pressure controller, a pressure transmitter and a gas compensator connected in sequence.

[0043] The gas compensation container 405 uses a syringe. The output end of the gas compensator is connected to a reversing solenoid valve assembly, which includes two three-way solenoid valves for connecting to the solenoid valve under test. One three-way solenoid valve has its NC terminal connected to air and its NO terminal connected in series with the gas compensation container 405. The other three-way solenoid valve has its NO terminal connected to air and its NC terminal connected in series with the gas compensation container 405. The COM terminals of the two three-way solenoid valves are connected to the input and output terminals of the solenoid valve under test, respectively.

[0044] The number of two-way solenoid valves, pressure controllers, pressure transmitters, gas compensators, and reversing solenoid valve assemblies 406 are all multiple and the number is the same.

[0045] Vacuum regulating valve 402 is connected to multi-way distributor 5, and each of the multi-way output terminals of multi-way distributor 5 is connected to a two-way solenoid valve.

[0046] like Figure 2-3 As shown, the electromagnetic valve negative pressure automatic testing device of the present invention includes a frame assembly 1, on which a clamping fixture 2, a control system 3 and an air circuit assembly 4 are provided.

[0047] The clamping fixture 2 is located in the center of the table surface of the frame assembly 1. The solenoid valve to be tested is clamped on the clamping fixture 2. The control system 3 is mainly located in the rear of the frame assembly 1, and the air circuit assembly 4 is mainly located in the front and rear of the frame assembly 1. The frame assembly 1 is equipped with a main switch 302d, a host computer 301, a three-color light 302c, an emergency stop button 302e, an indicator light 302g, and a test start button 302f. The main switch 302d supplies power to all components of the equipment. The test start button 302f is used to start the negative pressure test process of the solenoid valve. The host computer 301 can set the test parameters. In this application, 10 solenoid valves can be tested at a time, but it is not limited to 10.

[0048] like Figure 4-5 As shown in Figures 8-10, the frame assembly 1 includes a front baffle 101, a left side panel 102, a right side panel 103, a front panel 104, a tabletop panel 105, a top panel 106, a bottom panel 107, feet 108, a lower panel 109, a door panel 110, an electrical control board 111, a pressure controller mounting plate 112, and a frame 113. The front baffle 101, left side panel 102, right side panel 103, front panel 104, tabletop panel 105, top panel 106, and bottom panel 107 are all part of the frame assembly. 7. The foot 108, lower panel 109, door panel 110, and electrical control board 111 are bolted to the frame 113. The pressure controller mounting plate 112 is bolted to the left side panel 102 and the right side panel 103. The front panel 104 has 10 power lead holes for leading out the power supply terminal of the solenoid valve under test. The frame 113 is L-shaped. This structure facilitates the layout of the air and circuits and enhances the intuitiveness and portability during testing.

[0049] like Figure 11-12 As shown, the clamping fixture 2 is used to clamp the solenoid valve to be tested. It includes an upper cover plate 201, a lower cover plate 202, and a rubber seal 203. The upper cover plate 201 and the lower cover plate 202 have 10 holes respectively. The rubber seal 203 is inserted between the upper cover plate 201 and the lower cover plate 202 by interference fit. The clamping fixture 2 is fixed to the table panel 105 by bolts. The rubber seal 203 is provided with two or three air holes, which can be customized according to the specific specifications and models of the solenoid valve to be tested.

[0050] The control system 3 is mainly used to control the overall program operation, status detection, and parameter setting of the equipment. It includes a host computer 301 and an electrical system 302. The electrical system 302 mainly includes an external power supply module 302a, a relay group 302b, a tri-color indicator light 302c, a main switch 302d, an emergency stop button 302e, a test start button 302f, and indicator lights 302g, among other related electronic components. The external power supply module 302a is placed on the base plate 107, consisting of one 12V and one 24V module. The relay group 302b and related electronic components are installed on the electrical control... On panel 111, tri-color light 302c is installed on top panel 106, main switch 302d and indicator light 302g are installed on front panel 104, emergency stop button 302e and test start button 302f are installed on platform 105; electrical system 302 is electrically connected to host computer 301 and solenoid valve negative pressure test system respectively; solenoid valve negative pressure test system is located inside frame assembly 1, host computer 301 is used to set test parameters, can set the specifications, judgment criteria and product test number of the solenoid valve under test, and upload the final test data to cloud storage.

[0051] The output of the external power module 302a is connected to the input of the relay group 302b. The output of the relay group 302b is electrically connected to the host computer 301 and the solenoid valve negative pressure test system, respectively. The test start button 302f is connected to the input of the host computer 301. The main switch 302d, the emergency stop button 302e, and the main switch 302d are all located between the external power module 302a and the relay group 302b. The inputs of the tri-color light 302c and the indicator light 302g are both connected to the output of the host computer 301. The tri-color light 302c is used to send a signal to the host computer to provide an alarm reminder when a test fault occurs. The number of indicator lights 302g is the same as the number of solenoid valves under test. The host computer sends a signal, and the test results of the solenoid valves under test are displayed through different colors to indicate whether they are qualified or not.

[0052] The gas path assembly 4 is the aforementioned solenoid valve negative pressure test system, which includes a vacuum pump 401, a vacuum pressure valve 402, a pressure controller assembly 403, a pressure transmitter assembly 404, a gas compensation container assembly 405, a reversing solenoid valve assembly 406, and a solenoid valve assembly 407.

[0053] like Figure 10 As shown, the vacuum pump 401 is fixed to the base plate 107 by bolts, and the multi-channel distributor 5 expands one gas source into 10 gas sources. The multi-channel distributor 5 is fixed to the base plate 107 by bolts. The vacuum pressure valve 402 is fixed to the front panel 104 by bolts, which can adjust the pressure value in the gas path during the test.

[0054] like Figure 6-7As shown, the pressure controller assembly 403 includes pressure controllers 403-01 to 403-10, a total of 10, and a pressure controller mounting plate 112. Each pressure controller is mounted on the pressure controller mounting plate 112 and further mounted on the left side plate 102 and the right side plate 103, with five controllers mounted on each side.

[0055] like Figure 14 As shown, the pressure transmitter assembly 404 includes 10 pressure transmitters 404-1 to 404-10. Each pressure transmitter in the pressure transmitter assembly 404 is evenly arranged and fixed on the lower panel 109. Each pressure controller in the pressure controller assembly 403 is connected in series with each pressure transmitter in the pressure transmitter assembly 404. Each pressure transmitter in the pressure transmitter assembly 404 is connected in series with each syringe in the gas compensation container assembly 405. Each pressure transmitter assembly 404 converts the pressure signal in the gas path into an electrical signal. The pressure controller assembly 403 converts this electrical signal into a digital signal and feeds it back to the host computer 301, further improving the accuracy and precision of the solenoid valve negative pressure test.

[0056] like Figure 16 As shown, the gas compensation container assembly 405 includes syringes 405-1 to 405-10, a total of 10 syringes, which are mounted on the electronic control board 111 via a compensator fixing assembly 6. The compensator fixing assembly 6 includes clamping plates 601, 602, 603, and 604. Clamping plates 601 and 602 are vertically connected. Clamping plate 601 is fixed to the frame assembly 1. The frame assembly 1 has multiple sets of mounting holes on the upper and lower sides of clamping plate 601. Clamping plate 602 fixes the piston ends (i.e., the movable ends) of each syringe in the gas compensation container assembly 405 with bolts. 03 and clamping plate 604 are vertically connected. Clamping plate 604 is fixed on the frame assembly 1. Clamping plate 603 fixes the cavity ends of each syringe in the gas compensation container assembly 405 with bolts. Each syringe in the gas compensation container assembly 405 can be connected to mounting holes of different heights through clamping plate 601, thereby realizing the extension and shortening of the syringe and achieving the function of controlling the cavity volume. The compensator fixing assembly 6 can extend and shorten each syringe in the gas compensation container assembly 405 to achieve the corresponding cavity volume according to the test requirements, and is fixed on the electronic control board 111 with bolts.

[0057] like Figure 15As shown, the reversing solenoid valve assembly 406 includes 20 three-way solenoid valves 406-1 to 406-20 and a three-way solenoid valve mounting plate 7. Three-way solenoid valves 406-1 and 406-2 form one reversing group, while the remaining nine groups are arranged sequentially and fixed to the three-way solenoid valve mounting plate 7 with bolts. The COM terminals of three-way solenoid valves 406-1, 406-3, 406-5, 406-7, 406-9, 406-11, 406-13, 406-15, 406-17, and 406-19 are connected to the clamping fixture 2 via threaded connectors 8. The NC terminal is connected to air, and the NO terminal is connected in series with the corresponding gas compensation container. The COM terminal of the three-way solenoid valves 406-2, 406-4, 406-6, 406-8, 406-10, 406-12, 406-14, 406-16, 406-18, and 406-20 is connected to the clamping fixture 2 via threaded connector 8. The NO terminal is connected to air, and the NC terminal is connected in series with each syringe in the corresponding gas compensation container assembly 405. The pressure transmitter assembly 404, the pressure controller assembly 403, and the gas compensation container assembly 405 are connected in series, such as... Figure 13 As shown, the solenoid valve assembly 407 includes ten two-way solenoid valves 407-1 to 407-10, and a solenoid valve mounting plate 9. The ten two-way solenoid valves are arranged in sequence and fixed to the solenoid valve mounting plate 9 with bolts. The input ends of each two-way solenoid valve in the solenoid valve assembly 407 are connected in parallel and then connected in series with the vacuum pump 401. The output ends of each two-way solenoid valve in the solenoid valve assembly 407 are connected in parallel and then connected in series with each pressure controller in the pressure controller assembly 403. Thus, all paths in the gas path assembly are connected in series. According to the design path, the equipment testing efficiency and testing accuracy are greatly improved.

[0058] Vacuum pump 401, vacuum regulating valve 402, two-way solenoid valve, pressure controller, pressure transmitter and gas compensator are connected in sequence. Vacuum regulating valve 402 is connected to multi-way distributor 5. Each of the multi-way distributor 5's multiple output terminals is connected to a two-way solenoid valve.

[0059] The test method using the solenoid valve negative pressure automatic test device described above includes the following steps:

[0060] 1) Clamping of the solenoid valve under test

[0061] The solenoid valves to be tested are clamped onto the clamping fixture 2. According to the model and specifications of the solenoid valves and the test standards, the corresponding test parameters are selected on the host computer 301. The power leads are clamped, and the test start button 302f is pressed to start the test.

[0062] 2) Negative pressure test

[0063] according to Figure 16This device is an automatic negative pressure tester. Press the test start button 302f. The device will run from start to finish. The test structure is equipped with a vacuum pump 401 whose inlet is connected to the input of the vacuum pressure valve 402. The input port a of the two-way solenoid valve 407-01 is connected to the output of the vacuum pressure valve 402. The output port b of the two-way solenoid valve 407-01 is connected in series with the pressure gauge controller 403-01, the pressure transmitter 404-01, and the gas compensation container 405-01. From the end of the gas compensation container 405-01, two branches are generated. One inlet is connected to the normally open terminal d of the three-way solenoid valve 406-01, and the common terminal c of the three-way solenoid valve 406-01 is connected to the input terminal m of the solenoid valve under test. The other inlet is connected to the normally closed terminal h of the three-way solenoid valve 406-02, and the common terminal f of the three-way solenoid valve 406-02 is connected to the input terminal n of the solenoid valve under test.

[0064] In operation, a negative pressure test is first performed on the input terminal m of the solenoid valve under test. The working process is as follows: the vacuum pump 401 and the two-way solenoid valve 407-01 are energized simultaneously. The three-way solenoid valve 406-01, the three-way solenoid valve 406-02, and the solenoid valve under test are not working. After the negative pressure is drawn to the target value, the vacuum pump 401 and the two-way solenoid valve 407-01 are turned off simultaneously. The pressure controller 403 uploads the final reading to the host computer 301 to determine whether the solenoid valve under test is leaking. After the determination is completed, the solenoid valve under test is energized to release the gas pressure in the pipeline, and all components are turned off.

[0065] Next, a negative pressure test is performed on the output terminal n of the solenoid valve under test. The working process is as follows: the vacuum pump 401, the two-way solenoid valve 407-01, the three-way solenoid valve 406-01, and the three-way solenoid valve 406-02 are energized at the same time. The solenoid valve under test does not work. After the negative pressure is drawn to the target value, the vacuum pump 401 and the two-way solenoid valve 407-01 are turned off at the same time. The three-way solenoid valves 406-01 and 406-02 are kept energized. The pressure controller 403 uploads the final reading to the host computer 301 to determine whether the solenoid valve under test is leaking. After the determination is completed, the solenoid valve under test is energized, the three-way solenoid valve 406-01 is de-energized, the gas pressure in the pipeline is released, and all components are turned off.

[0066] Among them, the pressure transmitter 404-01 converts the pressure signal into an electrical signal, and the pressure controller 403-01 converts the electrical signal into a digital signal. After each pressure acquisition, the real-time pressure data will be displayed on the controller interface, and the test data will be uploaded to the host computer 301. The system will judge whether the test results are qualified or not, and store and record the test data and results.

[0067] 3) End the negative pressure test of the solenoid valve.

[0068] This testing device is easy to operate and can not only effectively improve the efficiency of negative pressure testing of solenoid valves and realize the automation of negative pressure testing, but also avoid the influence of human factors on the test results during the testing process.

[0069] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0070] It should be understood that the above description is for illustrative purposes and not for limitation. Many embodiments and applications beyond the provided examples will be apparent to those skilled in the art upon reading the above description. Therefore, the scope of this teaching should not be determined by reference to the above description, but rather by reference to the foregoing claims and the full scope of their equivalents. For purposes of completeness, all articles and references, including patent applications and publications, are incorporated herein by reference. The omission of any aspect of the subject matter disclosed herein in the foregoing claims is not intended as a waiver of that subject matter, nor should it be construed as an indication that the applicant has not considered that subject matter as part of the disclosed inventive subject matter.

Claims

1. An automatic testing device for negative pressure of a solenoid valve, characterized in that, It includes a frame assembly (1), a clamping fixture (2), a control system (3) and a solenoid valve negative pressure test system. The solenoid valve negative pressure test system includes a vacuum pump (401), a vacuum regulating valve (402), a two-way solenoid valve, a pressure controller, a pressure transmitter and a gas compensation container connected in sequence. The output end of the gas compensation container is connected to a reversing solenoid valve group. The reversing solenoid valve group includes two three-way solenoid valves for connecting the solenoid valve under test. The NC end of one three-way solenoid valve is connected to air, and the NO end is connected in series with the gas compensation container (405). The NO end of the other three-way solenoid valve is connected to air, and the NC end is connected in series with the gas compensation container (405). The COM ends of the two three-way solenoid valves are connected to the input end and the output end of the solenoid valve under test, respectively. The gas compensation container uses a syringe; The number of two-way solenoid valves, pressure controllers, pressure transmitters, gas compensation containers, and reversing solenoid valve groups are all multiple and the number is the same. The vacuum regulating valve (402) is connected to a multi-way distributor (5), and each of the multi-way output terminals of the multi-way distributor (5) is connected to a two-way solenoid valve. The method for testing the negative pressure of a solenoid valve includes: performing a negative pressure test on the input end of the solenoid valve under test: the vacuum pump (401) and the two-way solenoid valve are energized simultaneously, while the two three-way solenoid valves and the solenoid valve under test are not working. After the negative pressure is drawn to the target value, the vacuum pump (401) and the two-way solenoid valve are turned off simultaneously. The pressure controller uploads the final reading to determine whether the solenoid valve under test is leaking. After the determination is completed, the solenoid valve under test is energized to release the gas pressure in the pipeline, and all components are turned off. A negative pressure test is performed on the output end of the solenoid valve under test: the vacuum pump (401), the two-way solenoid valve and the two three-way solenoid valves are energized at the same time, the solenoid valve under test does not work, and after the negative pressure is drawn to the target value, the vacuum pump (401) and the two-way solenoid valve are turned off at the same time, and the two three-way solenoid valves are continuously energized. The pressure controller uploads the final reading to determine whether the solenoid valve under test is leaking. After the determination is completed, the solenoid valve under test is energized, and the three-way solenoid valve connected to the input end of the solenoid valve under test is de-energized to release the gas pressure in the pipeline. The frame assembly (1) is hollow inside, and the top surface of the frame assembly (1) is a table; the clamping fixture (2) is located in the center of the table of the frame assembly (1), and the clamping fixture (2) is used to clamp the solenoid valve to be tested. The control system (3) is installed on the frame assembly (1). The control system (3) includes a host computer (301) and an electrical system (302). The host computer (301) is interconnected with each component in the solenoid valve negative pressure test system. The electrical system (302) is electrically connected to the host computer (301) and the solenoid valve negative pressure test system respectively. The solenoid valve negative pressure test system is located inside the frame assembly (1). The reversing solenoid valve group is connected to the bottom of the clamping fixture (2). A gas compensation container fixing assembly (6) is provided on the frame assembly (1). The gas compensation container fixing assembly (6) includes a first clamp (601), a second clamp (602), a third clamp (603), and a fourth clamp (604). The first clamp (601) and the second clamp (602) are vertically connected. The first clamp (601) is fixed on the frame assembly (1). The frame assembly (1) has multiple sets of mounting holes on the upper and lower sides of the first clamp (601). The second clamp (602) is connected to the movable end of the gas compensation container. The third clamp (603) and the fourth clamp (604) are vertically connected. The fourth clamp (604) is fixed on the frame assembly (1). The third clamp (603) is connected to the cavity end of the gas compensation container. The clamping fixture (2) includes an upper cover plate (201), a lower cover plate (202) and a rubber seal (203). The upper cover plate (201) and the lower cover plate (202) have mounting holes in corresponding areas. The rubber seal (203) is connected between the upper cover plate (201) and the lower cover plate (202) and is interference-fitted with the mounting holes. The rubber seal (203) has two or three air holes.

2. The automatic negative pressure testing device for a solenoid valve according to claim 1, characterized in that, The electrical system (302) includes an external power supply module (302a), a relay group (302b), a main equipment switch (302d), an emergency stop button (302e), and a test start button (302f). The output of the external power supply module (302a) is connected to the input of the relay group (302b). The output of the relay group (302b) is electrically connected to the host computer (301) and the solenoid valve negative pressure test system, respectively. The test start button (302f) is connected to the input of the host computer (301). The emergency stop button (302e) and the main equipment switch (302d) are both located between the external power supply module (302a) and the relay group (302b).

3. The automatic negative pressure testing device for a solenoid valve according to claim 1, characterized in that, The rack assembly (1) is equipped with a tri-color lamp (302c) and an indicator light (302g). The input terminals of the tri-color lamp (302c) and the indicator light (302g) are connected to the output terminal of the host computer (301).

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