Injector test fixture and method

Abstract

The present invention discloses a fuel injector testing tool and method, pertaining to the field of DC-controlled fuel injector performance testing for large diesel engines. The fuel injector testing tool utilizes a battery to provide DC power, eliminating the complex technical methods of injector pulse power supply testing. Fluorescent test fluid and a test plate effectively test the injector's key technical functions. The test body includes a replaceable inner sleeve with multiple specifications, a high-pressure test fluid adapter at the bottom of the solenoid valve, a displaceable high-pressure transmission tube, and a high-pressure test gauge, enabling the reading of test pressure. The present invention simplifies the injector installation process during testing and ultimately displays the injector's spray status in a standardized manner.

Description

Technical Field

[0001] The invention belongs to the field of performance testing of a direct current controlled fuel injector of a large internal combustion engine, and in particular relates to a fuel injector testing tool and method. Background Art

[0002] Prior art similar to this invention includes the fuel injector control device 201720350571.7 and the electronic fuel injector connection device 201720352520.8. The methods, structures, and principles of these inventions are applicable to testing the atomization performance of conventional fuel injectors used in automotive engines. The testing method utilizes the control functions of the original vehicle's electronic control module, and the installation method employs a mechanical fuel injector jig as the main body fixture for the fuel injector. The fuel supply for high-pressure testing is supplied by a high-pressure gun used in mechanical fuel injector performance testing, and the fuel supply transmission utilizes the threaded pipe fastening spherical seal structure used in mechanical testing.

[0003] When installing and testing the injector, the installation process is complicated and time-consuming, and the injector sealing and spray status cannot be determined intuitively. Summary of the Invention

[0004] The object of the present invention is to provide a fuel injector testing tool and method for simplifying the installation process of the fuel injector during testing and ultimately displaying the spray state of the fuel injector in a standardized manner.

[0005] In order to achieve the above object, the present invention provides the following technical solutions:

[0006] A fuel injector test fixture, used for a fuel injector with a sealing rubber ring, comprising:

[0007] A bucket with test fluid;

[0008] A DC control power supply, the DC control power supply being electrically connected to the solenoid valve of the fuel injector;

[0009] a support body, wherein the support body is provided with an injector mounting hole for accommodating the injector and an oil supply and return passage, and the test fluid is communicated with the injector mounting hole through the oil supply and return passage;

[0010] a pressure supply device located above the supporting body, the pressure supply device being used to drive the injector to spray oil;

[0011] an atomization test plate located below the injector mounting hole;

[0012] When the injector is inserted into the injector mounting hole, the space between the sealing rubber rings of the injector forms an annulus, the oil supply and return channels are connected to the annulus, and the injection port of the injector faces the atomization test plate.

[0013] The test liquid is diesel mixed with 5% to 10% fluorescent substance; or

[0014] The test liquid is gasoline mixed with 5% to 10% fluorescent substance.

[0015] The fluorescent substance is a fluorescent powder that glows after being irradiated by ultraviolet rays.

[0016] The DC control power supply includes a DC power supply and a quick plug connector. The DC power supply is electrically connected to the solenoid valve of the injector through the quick plug connector. The shape of the electrical connection port of the quick plug connector matches the shape of the electrical connection port of the solenoid valve.

[0017] The injector test tool also includes a liquid supply pump, a pressure regulating valve and a second pressure gauge. The liquid inlet of the liquid supply pump is connected to the test liquid, and the liquid outlet of the liquid supply pump is connected to the oil supply and return channel. The pressure regulating end of the pressure regulating valve is arranged in the oil supply and return channel, and the measuring end of the second pressure gauge is located in the oil supply and return channel.

[0018] The fuel injector testing tool further includes a first pressure gauge for testing the pressure of the test fluid in the fuel injector cavity, and the first pressure gauge is communicated with the interior of the fuel injector.

[0019] The injector test fixture further includes a conversion head and a test channel located in the support body;

[0020] The outer surface of the conversion head is in the shape of two inverted frustums, the diameters of the two ends of the conversion head are smaller than the diameter of the middle part, and an overflow channel is provided in the conversion head;

[0021] The test channel is provided with the conversion head at one end, the test channel with the conversion head is located at the top of the support body, and the other end of the test channel is connected to the first pressure gauge;

[0022] When the fuel injector is inserted into the fuel injector mounting hole, the bypass liquid outlet of the fuel injector is connected to the first pressure gauge through the conversion head.

[0023] The pressure supply device includes a bracket and a linear power supply device, and the working end of the linear power supply device is opposite to the power receiving end of the injector.

[0024] A fuel injector testing method, used with the above-mentioned fuel injector testing tool, comprising:

[0025] Step 1: Install the fuel injector into the fuel injector mounting hole on the support body, and place the atomization test plate directly below the injection port of the fuel injector;

[0026] Step 2: Pass the test liquid into the annulus formed by the space between the sealing rubber rings of the injector;

[0027] Step 3: The pressure supply device applies pressure to the fuel injector at a predetermined frequency to drive the fuel injector to spray fuel onto the atomization test board.

[0028] In step 3, when the fuel injector is injecting fuel, the pressure inside the fuel injector is measured.

[0029] Compared to existing technologies, the injector testing tool and method provided by the present invention utilizes a DC control power supply to control the injector's solenoid valve, ensuring normal fuel injection. The injector's spray status is visually displayed on the atomization test plate using test fluid and an atomization test plate. Furthermore, a pioneering injector mounting hole is provided on the support body, enabling the injector with a sealing rubber ring to fit within the mounting hole. An annulus is then formed between the injector's sealing rubber rings. Test fluid is then introduced into this annulus, completing the injection process. This invention simplifies the injector installation process and ultimately provides a standardized display of the injector's spray status. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is a schematic diagram of the overall structure of the fuel injector test fixture of the present invention;

[0031] Figure 2 This is a schematic structural diagram of the quick plug connector of the fuel injector test fixture of the present invention;

[0032] Figure 3 This is a schematic structural diagram of the atomization test plate of the fuel injector test fixture of the present invention;

[0033] Figure 4 This is a schematic structural diagram of the conversion head of the fuel injector test fixture of the present invention;

[0034] Figure 5 A schematic structural diagram of a conversion head of the fuel injector test fixture of the present invention having a fuel injector installation adapter set;

[0035] Figure 6 Schematic diagram of the structure of the adapter kit for injector installation;

[0036] Figure 7 It is a partial structural schematic diagram of an embodiment of the fuel injector test fixture of the present invention having a sliding groove;

[0037] Figure 8 This is a partial structural diagram of another embodiment of the injector test fixture of the present invention having a sliding groove.

[0038] Figure numerals: 1. Injector; 11. Plunger pump; 12. Solenoid valve; 2. Test fluid; 3. DC control power supply; 4. Support body; 41. Oil supply and return channel; 411. Second pressure gauge; 412. Pressure regulating valve; 42. Injector mounting hole; 43. Pad; 44. Bracket; 45. Injector mounting adapter; 46. Sliding groove; 5. Pressure supply device; 6. Atomization test plate; 7. First pressure gauge; 8. Test channel; 81. Conversion head; 811. Flow hole; 9. Liquid supply pump; 10. Quick plug connector. DETAILED DESCRIPTION

[0039] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0040] The present invention will be further described in detail below with reference to specific embodiments, which are intended to explain the present invention rather than to limit it.

[0041] Please refer to Figure 1 , which shows a schematic diagram of the overall structure of the injector test fixture of the present invention. The injector test fixture is used for an injector 1 with a sealing rubber ring, and includes: a barrel with a test liquid 2, a DC control power supply 3, a support body 4, a pressure supply device 5 and an atomization test plate 6.

[0042] The holding bucket is used to hold the test liquid 2.

[0043] The test fluid 2 is diesel mixed with 5% to 10% fluorescent material. Alternatively, the test fluid 2 is gasoline mixed with 5% to 10% fluorescent material. The fluorescent material is a fluorescent powder that glows when irradiated with ultraviolet light. For example, the fluorescent powder is yttrium oxide doped with europium. To ensure proper operation of the injector 1, the fluorescent powder needs to be finer than 600 mesh. Preferably, the fluorescent powder has a fineness of 800 mesh.

[0044] The above-mentioned DC control power supply 3 is used to be electrically connected to the solenoid valve 12 of the injector 1. The DC control power supply 3 is used to control the opening and closing of the solenoid valve 12 of the injector 1. The DC control power supply 3 includes a DC power supply and a quick plug connector 10. The DC power supply is electrically connected to the solenoid valve 12 of the injector 1 through the quick plug connector 10. The shape of the electrical connection port of the quick plug connector 10 matches the shape of the electrical connection port of the solenoid valve 12.

[0045] The DC control power supply 3 uses DC power and a button switch for power control, such as Figure 2As shown, the two positive and negative terminals of the quick-connect connector 10 are directly electrically connected to the positive and negative terminals of the solenoid valve 12. This differs from other similar methods by simplifying the complex pulsed DC control power supply used in other theoretical methods to a simple, inexpensive, and practical DC power supply. This DC power supply is a 12V battery; the power connection utilizes a quick-connect connector 10 for quick and convenient circuit connection.

[0046] The support body 4 is provided with an injector mounting hole 42 and an oil supply and return passage 41 for accommodating the injector 1. The test fluid 2 is communicated with the interior of the injector mounting hole 42 through the oil supply and return passage 41, and the oil supply and return passage 41 is communicated with the annulus. The shape of the injector mounting hole 42 is adapted to the shape of the inserted injector 1, for example, Figure 1 The shapes of the middle injector 1 from the front end to the rear end are truncated cone, cylindrical, and truncated cone, respectively. The shapes of the injector mounting hole 42 are also truncated cone, cylindrical, and truncated cone, respectively. When the injector 1 is inserted into the injector mounting hole 42, the space between the sealing rubber rings of the injector 1 forms an annulus, which can accommodate the test liquid 2. The oil inlet of the injector 1 is located between the two sealing rubber rings of the injector 1, and the oil inlet of the injector 1 is connected to the annulus. The surface roughness of the inner hole of the injector mounting hole 42 is ≤3.2um. The inner surface of the injector mounting hole 42 is tightly matched with the upper O-ring and the lower O-ring of the injector 1. During the later test, if the two sealing rubber rings of the injector 1 leak, it means that the sealing performance of the two sealing rubber rings does not meet the requirements. The oil supply and return passage 41 is divided into an oil supply passage and an oil return passage. The oil supply passage and the oil return passage allow the test fluid 2 to continuously flow through the annulus formed between the injector mounting hole 42 and the injector 1 .

[0047] Specifically, the support body 4 is a square member with support members at both ends to support the support body 4 on a stable base. The axial direction of the injector mounting hole 42 coincides with the vertical centerline of the support body 4. The injector mounting hole 42 is processed with threads and sealing steps, and can be equipped with a variety of replaceable injector mounting adapter sets 45. By installing and replacing adapter sets of different specifications, it can be applied to the installation of different types of injectors, realizing the performance testing of multiple specifications of injectors, such as Figure 5 and Figure 6 shown.

[0048] The driving force for the test fluid 2 is provided by a fluid supply pump 9. The test fluid 2 within the annulus is pumped by the fluid supply pump 9, which draws in the test fluid 2, increasing its pressure. The fluid 2 is then pumped into the oil supply channel, where it is then pumped into the annulus. Excess test fluid 2 flows back into the storage tank via the oil return channel. A pressure regulating valve is installed in the oil return channel, and the measuring end of a second pressure gauge 411 is located within the channel. The internal pressure of the oil return channel is adjusted to 600 kPa ± 50 kPa via the pressure regulating valve and the second pressure gauge 411.

[0049] The pressure supply device 5 is located above the support body 4, and the pressure supply device 5 is used to drive the injector 1 to spray oil. The pressure supply device 5 includes a bracket 44 and a linear power supply device, and the working end of the linear power supply device is opposite to the power receiving end of the injector 1. The linear power supply device is used to press down the plunger pump 11 of the injector 1 to increase the pressure of the test liquid in the injector 1. The linear power supply device can be a linear power supply device composed of a servo motor and a ball screw nut pair. In another embodiment, the linear power supply device is a hand lever type hand pressure rod, which is driven by manpower. Specifically, the hand pressure rod is a hand pressure type single hinge lever.

[0050] The atomization test plate 6 is located below the injector mounting hole 42, and the injection port of the injector 1 faces the atomization test plate 6. The atomization test plate 6 is used to receive the mist test liquid 2 sprayed by the injector 1 and determine the atomization condition of the injector 1 based on the received mist test liquid 2. Figure 3 As shown, the upper surface of the atomization test plate 6 is arranged with several annular areas extending from the inside out. These annular areas are further divided into small grid-like test areas. After the injector 1 completes the injection, the test liquid 2 can be illuminated by an ultraviolet lamp. The phosphor in the test liquid 2 emits light under the ultraviolet lamp. The brightness distribution of each test area is then used to determine whether the injection of the injector 1 is uniform and within the predetermined injection angle range. For example, the typical injection angle of the injector 1 is 120 degrees. When the atomization test plate 6 is installed, the upper surface of the atomization test plate 6 is flush with the horizontal direction, and the angle between the line connecting the injector 1's nozzle and the edge of the atomization test plate 6 and the upper surface of the atomization test plate 6 is less than 60 degrees. The height of the atomization test plate 6 is adjusted by the backing plate 43.

[0051] When the present invention is used, the application method is as follows:

[0052] a) Mix the fluorescent powder and -20# diesel in a ratio of 1:20 to form a test solution 2 that can be seen to fluoresce under ultraviolet light.

[0053] b) Place the atomization test plate 6 below the nozzle of the injector 1 and cover the atomization test plate 6 with a transparent cover.

[0054] c) Replace the lower plug of the solenoid valve 12 of the injector 1 to be tested with the conversion head 81, and insert the injector 1 into the injector mounting hole 42 of the support body 4 so that the injector 1 and the injector mounting hole 42 fit tightly. Figure 4 As shown, the middle of the conversion head 81 has a flow hole 811, which connects the first pressure gauge 7 with the inside of the injector 1.

[0055] d) Start the low-pressure fluid supply system (A) and start the fluid supply pump 9 to supply the test fluid 2 to the injector 1 through the oil supply and return passage 41. The fluid supply pressure is adjusted to 0.2-0.4 MPa. The fluid circulates for 1 minute. Use ultraviolet light to inspect the entire injector for signs of fluorescence, thereby completing the static leak test of the injector 1.

[0056] e) The plunger pump 11 of the fuel injector 1 is reciprocated downwardly through the pressure supply device 5 at a rate of ≥10 times / min. The flexibility of the matching components of the plunger pump 11 and the performance of the spring can be tested by measuring the pressure curve provided by the pressure supply device 5. A pressure sensor can be installed at the end of the pressure supply device 5 for testing when measuring the pressure curve provided by the pressure supply device 5.

[0057] f) Put the cap-shaped quick plug connector onto the solenoid valve 12, and the electrodes in the injector cap will automatically align and contact with the two-pole terminals of the solenoid valve through the bell mouth, finally electrically connecting the DC control power supply 3 and the solenoid valve 12 to each other.

[0058] g) Intermittently turn on and off the DC power to the solenoid valve 12, monitor the sound of the solenoid valve core moving, and test the sensitivity of the solenoid valve opening and closing function. The sound should be crisp and clear.

[0059] h) Continuously supplying DC power to solenoid valve 12 closes the circulation loop of test fluid 2 within injector 1, sealing test fluid 2 within injector 1. Simultaneously, pressure is supplied to injector 1's plunger pump 11 via pressure supply device 5, increasing the pressure within injector 1. The internal pressure of injector 1 is measured using a first pressure gauge 7 located adjacent to injector 1. When the internal pressure reaches a preset value, the internal pressure overcomes the spring pressure on the upper portion of the needle valve of the injector nozzle assembly, causing the needle valve to open and instantaneously eject test fluid 2.

[0060] i) After the test liquid 2 is sprayed, the sprayed liquid falls on the atomization test plate 6. Through ultraviolet irradiation and observation, the atomization uniformity and spray angle of the sprayed liquid can be clearly judged, achieving the detection target.

[0061] j) Continue to power the solenoid valve 12 and pressurize the plunger pump 11 of the injector 1 through the pressure supply device 5. When the data measured by the first pressure gauge 7 reaches the critical injection value of the injector 1, stop pressurizing the plunger pump 11 and maintain the pressure for 5 seconds. At the same time, observe the sealing condition of the injector nozzle. If it is in good condition, there should be no signs of leakage of the test fluid. Complete all tests on the injector 1.

[0062] In summary, the injector testing tool and method provided by the present invention utilizes a DC control power supply to control the injector's solenoid valve, enabling the injector to spray properly. The injector's spray status is visually displayed on the atomization test plate via test fluid and an atomization test plate. A groundbreaking design incorporates injector mounting holes in the support body, enabling the injector with a sealing rubber ring to engage with the mounting holes. An annulus is then formed between the injector's sealing rubber rings, allowing the test fluid to be introduced into the annulus, completing the injection process. This invention simplifies the injector installation process during testing and ultimately displays the injector's spray status in a standardized manner.

[0063] For further information, please refer to Figure 1 In another embodiment of the fuel injector test fixture of the present invention, the fuel injector 1 test fixture further includes a first pressure gauge 7 for testing the pressure of the test fluid 2 in the inner cavity of the fuel injector 1, and the first pressure gauge 7 is connected to the interior of the fuel injector 1.

[0064] The injector test fixture further includes a conversion head 81 and a test channel 8 located in the support body 4;

[0065] The outer surface of the conversion head 81 is in the shape of two inverted frustums. The diameters of the two ends of the conversion head 81 are smaller than the diameter of the middle part. An overflow channel is provided in the conversion head 81.

[0066] The test channel 8 is provided with the conversion head 81 at one end, and the test channel 8 with the conversion head 81 is located at the top of the support body 4, and the other end of the test channel 8 is connected to the first pressure gauge 7;

[0067] When the injector 1 is inserted into the injector mounting hole 42 , the bypass outlet of the injector 1 is connected to the first pressure gauge 7 through the conversion head 81 .

[0068] In the above embodiment, the first pressure gauge 7 is used to test the pressure of the test fluid in the inner cavity of the injector 1. When the first pressure gauge 7 is connected to the injector 1, the plug at the lower end of the solenoid valve 12 of the injector 1 to be tested is replaced with a conversion head 81. When the injector 1 is inserted into the injector mounting hole 42, the bypass liquid outlet of the injector 1 is connected to the first pressure gauge 7 through the conversion head 81. Figure 1 and Figure 2As shown, this embodiment places the inlet of the test channel 8 directly below the injector 1. When the injector 1 is inserted into the injector mounting hole 42, the injector 1 is connected to the first pressure gauge 7 via the adapter 81 and the test channel 8. This facilitates the test connection process of the injector 1, saves experimental time, and improves testing efficiency.

[0069] For further information, please refer to Figure 7 and Figure 8 In another embodiment of the injector test fixture of the present invention, the test channel 8 is tubular and slidably connected to the support body 4. The top of the support body 4 has a sliding groove 46. One end of the test channel 8 with a conversion head 81 is located in the sliding groove 46. When the tubular test channel 8 and the support body 4 slide back and forth, the conversion head 81 moves back and forth in the sliding groove 46.

[0070] In the above embodiment, by providing the sliding groove 46, the relative distance between the conversion head 81 and the solenoid valve 12 can be adjusted, so that the injector test fixture of the present invention can adapt to solenoid valves 12 of different specifications. Figure 7 and Figure 8 Two different solenoid valves are shown.

[0071] The present invention also discloses a fuel injector testing method, which is used for the above-mentioned fuel injector testing tool, comprising:

[0072] Step 1: Install the fuel injector 1 into the fuel injector mounting hole 42 on the support body 4, and place the atomization test plate 6 directly below the injection port of the fuel injector 1;

[0073] Step 2: Pass the test liquid 2 into the annulus formed by the space between the sealing rubber rings of the injector 1;

[0074] Step 3: The pressure supply device 5 applies pressure to the fuel injector 1 at a predetermined frequency, driving the fuel injector 1 to spray fuel onto the atomization test plate 6.

[0075] In step 3, when the fuel injector 1 is injecting fuel, the pressure inside the fuel injector 1 is measured.

[0076] In the above embodiment, specifically:

[0077] a) Mix the fluorescent powder and -20# diesel in a ratio of 1:20 to form a test solution 2 that can be seen to fluoresce under ultraviolet light.

[0078] b) Place the atomization test plate 6 below the nozzle of the injector 1 and cover the atomization test plate 6 with a transparent cover.

[0079] c) Replace the lower plug of the solenoid valve 12 of the injector 1 to be tested with the conversion head 81, connect the first pressure gauge 7 to the inside of the injector 1, and insert the injector 1 into the injector mounting hole 42 of the support body 4 so that the injector 1 and the injector mounting hole 42 are tightly fitted.

[0080] d) Start the low-pressure fluid supply system (A) and start the fluid supply pump 9 to supply the test fluid 2 to the injector 1 through the oil supply and return passage 41. The fluid supply pressure is adjusted to 0.2-0.4 MPa. The fluid circulates for 1 minute. Use ultraviolet light to inspect the entire injector for signs of fluorescence, thereby completing the static leak test of the injector 1.

[0081] e) The plunger pump 11 of the fuel injector 1 is reciprocated downwardly through the pressure supply device 5 at a rate of ≥10 times / min. The flexibility of the matching components of the plunger pump 11 and the performance of the spring can be tested by measuring the pressure curve provided by the pressure supply device 5. A pressure sensor can be installed at the end of the pressure supply device 5 for testing when measuring the pressure curve provided by the pressure supply device 5.

[0082] f) Put the cap-shaped quick plug connector onto the solenoid valve 12, and the electrodes in the injector cap will automatically align and contact with the two-pole terminals of the solenoid valve through the bell mouth, finally electrically connecting the DC control power supply 3 and the solenoid valve 12 to each other.

[0083] g) Intermittently turn on and off the DC power to the solenoid valve 12, monitor the sound of the solenoid valve core moving, and test the sensitivity of the solenoid valve opening and closing function. The sound should be crisp and clear.

[0084] h) Continuously supplying DC power to solenoid valve 12 closes the circulation loop of test fluid 2 within injector 1, sealing test fluid 2 within injector 1. Simultaneously, pressure is supplied to plunger pump 11 of injector 1 via pressure supply device 5, increasing the pressure within injector 1. The pressure within injector 1 is measured using first pressure gauge 7. When the pressure within injector 1 reaches a preset value, the internal pressure overcomes the downward force of the spring on the needle valve of the injector nozzle assembly, causing the needle valve to open and instantaneously eject test fluid 2.

[0085] i) After the test liquid 2 is sprayed, the spray liquid falls on the atomization test plate 6. Through ultraviolet irradiation and observation, the atomization uniformity and spray angle of the spray liquid can be clearly judged, achieving the core detection goal of this innovative achievement.

[0086] Continuously power the solenoid valve 12 again, and pressurize the plunger pump 11 of the injector 1 through the pressure supply device 5. When the data measured by the first pressure gauge 7 reaches the critical injection value of the injector 1, stop pressurizing the plunger pump 11 and maintain it for 5 seconds. At the same time, observe the sealing condition of the injector nozzle. If it is in good condition, there should be no signs of leakage of the test fluid. Complete all tests on the injector 1.

[0087] It should be noted that when an element is referred to as being “fixed on” or “disposed on” another element, it may be directly on the other element or indirectly on the other element. When an element is referred to as being “connected to” another element, it may be directly connected to the other element or indirectly connected to the other element.

[0088] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Thus, a feature specified as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "plurality" means two or more, unless otherwise specifically defined. "Several" means one or more, unless otherwise specifically defined.

[0089] In the description of the present invention, it should be understood that the terms "up", "down", "front", "back", "left", "right", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.

[0090] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and may encompass internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0091] The basic principles, main features, and advantages of the present invention are shown and described above. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are merely illustrative of the principles of the present invention. Various changes and modifications may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and modifications are intended to fall within the scope of the present invention. The scope of protection claimed in the present invention is defined by the appended claims and their equivalents.

Claims

1. A fuel injector test fixture for a fuel injector with a sealing rubber ring, characterized in that: include: A bucket with test fluid; A DC control power supply, the DC control power supply being electrically connected to the solenoid valve of the fuel injector; a support body, wherein the support body is provided with an injector mounting hole and an oil supply and return passage for accommodating the injector, wherein the test liquid in the holding barrel is connected to the injector mounting hole through the oil supply and return passage; a pressure supply device located above the support body, wherein the pressure supply device is used to drive the injector to spray oil; an atomization test plate located below the injector mounting hole; when the injector is inserted into the injector mounting hole, an annulus is formed between the sealing rubber rings of the injector, the oil supply and return passage is connected to the annulus, and the injection port of the injector faces the atomization test plate; The annulus can accommodate the test fluid; The test liquid is diesel mixed with 5% to 10% fluorescent substance; or the test liquid is gasoline mixed with 5% to 10% fluorescent substance; The fluorescent substance is a fluorescent powder that glows after being irradiated by ultraviolet light; the coarseness of the fluorescent powder is less than 600 mesh; The DC control power supply includes a DC power supply and a quick plug connector, the DC power supply is electrically connected to the solenoid valve of the injector through the quick plug connector, and the shape of the electrical connection port of the quick plug connector matches the shape of the electrical connection port of the solenoid valve; The fuel injector test fixture further comprises a first pressure gauge for testing the pressure of the test fluid in the fuel injector cavity, wherein the first pressure gauge is in communication with the interior of the fuel injector; The injector test fixture also includes a conversion head and a test channel located in the support body; the outer surface of the conversion head is shaped like two inverted frustums, the diameters at both ends of the conversion head are smaller than the diameter in the middle, and an overflow channel is provided in the conversion head; the conversion head is provided at one end of the test channel, and one end of the test channel with the conversion head is located at the top of the support body, and the other end of the test channel is connected to the first pressure gauge; when the injector is inserted into the injector mounting hole, the bypass outlet of the injector is connected to the first pressure gauge through the conversion head.

2. The fuel injector test fixture according to claim 1, characterized in that: The injector test tool also includes a liquid supply pump, a pressure regulating valve and a second pressure gauge. The liquid inlet of the liquid supply pump is connected to the test liquid, and the liquid outlet of the liquid supply pump is connected to the oil supply and return channel. The pressure regulating end of the pressure regulating valve is arranged in the oil supply and return channel, and the measuring end of the second pressure gauge is located in the oil supply and return channel.

3. The fuel injector test fixture according to claim 1, characterized in that: The pressure supply device includes a bracket and a linear power supply device, and the working end of the linear power supply device is opposite to the power receiving end of the injector.

4. A fuel injector testing method, used for the fuel injector testing tool according to any one of claims 1 to 3, characterized in that: include: Step 1: Install the fuel injector into the fuel injector mounting hole on the support body, and place the atomization test plate directly below the injection port of the fuel injector; Step 2: Pass the test liquid into the annulus formed by the space between the sealing rubber rings of the injector; Step 3: The pressure supply device applies pressure to the fuel injector at a predetermined frequency to drive the fuel injector to spray fuel onto the atomization test board.

5. The fuel injector testing method according to claim 4, characterized in that: In step 3, when the fuel injector is injecting fuel, the pressure inside the fuel injector is measured.

6. The fuel injector testing method according to claim 4 or 5, characterized in that: a) Mix the fluorescent powder and 20# diesel in a ratio of 1:20 to form a test solution that can be seen to fluoresce under ultraviolet light; b) Place the atomization test plate under the nozzle of the injector and cover the atomization test plate with a transparent cover; c) Replace the lower plug of the solenoid valve of the injector to be tested with a conversion head, and insert the injector into the injector mounting hole of the support body so that the injector and the injector mounting hole fit tightly together; the conversion head has a flow hole in the middle, which connects the first pressure gauge with the interior of the injector; d) Turn on the low-pressure fluid supply system. The fluid supply pump supplies the test fluid to the injector through the oil supply and return channels. The fluid supply pressure is adjusted to 0.2-0.4 MPa. The fluid is circulated for 1 minute. Use ultraviolet light to detect whether the injector as a whole shows any signs of fluorescence. This completes the static sealing test of the injector. e) At a rate of ≥10 times / min, reciprocate and depress the plunger pump of the fuel injector through the pressure supply device, and at this time, test the flexibility of the plunger pump components and the performance of the spring by measuring the pressure curve provided by the pressure supply device; wherein, when measuring the pressure curve provided by the pressure supply device, install a pressure sensor at the end of the pressure supply device for testing; f) Put the quick connector of the cap sleeve on the solenoid valve, and pass the electrode in the injector cap through the bell mouth. Automatically align and contact with the two-pole terminals of the solenoid valve, and finally electrically connect the DC control power supply and the solenoid valve; g) Intermittently turn on and off the DC power to the solenoid valve, monitor the sound of the solenoid valve core, and test the sensitivity of the solenoid valve opening and closing function. The sound should be clear and crisp; h) Continuously supplying DC power to the solenoid valve, which, when energized, closes the circulation loop of the test fluid inside the injector, thereby sealing the test fluid inside the injector. Simultaneously, a pressure supply device supplies pressure to the plunger pump of the injector, thereby increasing the pressure inside the injector. The internal pressure of the injector is measured by a first pressure gauge provided next to the injector. When the internal pressure of the injector reaches a preset value, the internal pressure overcomes the downward pressure of the spring on the upper portion of the needle valve of the injector nozzle assembly, causing the needle valve to open and the test fluid to be instantly ejected. i) After the test liquid is sprayed, it falls on the atomization test plate. Through ultraviolet irradiation and observation, the atomization uniformity and spray angle of the spray liquid can be clearly judged to achieve the detection target; j) Continue to power the solenoid valve and pressurize the plunger pump of the injector through the pressure supply device. When the data measured by the first pressure gauge reaches the critical injection value of the injector, stop pressurizing the plunger pump and maintain it for 5 seconds. At the same time, observe the sealing condition of the injector nozzle. If it is in good condition, there should be no signs of leakage of the test fluid. Complete all tests on the injector.

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