JP6087312B2 - Fuel injection pump testing equipment - Google Patents

Description

  The present invention relates to a test apparatus for confirming sealing performance in a fuel injection pump.

  2. Description of the Related Art Conventionally, a fuel injection pump having a plunger pump and an electromagnetic valve that opens and closes communication between a discharge passage and a suction passage of the plunger pump is known. This fuel injection pump includes a valve block in which an electromagnetic valve is arranged, and the valve block is fixed to the plunger pump. Patent Document 1 discloses an example of such a fuel injection pump.

  The discharge passage is formed in the plunger pump and the valve block. A seal tube is provided at the contact portion between the plunger pump and the valve block in order to ensure the sealing performance of the discharge passage. In addition, in the unlikely event that fuel oil leaks from the discharge passage, a leak passage for collecting and detecting the oil leakage is provided in the valve block.

JP 2012-197698 A

  In the manufacturing process, since it is necessary to ensure that there is no oil leakage from the seal tube, a test for confirming the sealing performance of the seal tube is performed. As such a test, it is conceivable to check the sealing performance by filling the discharge passage with fuel oil and applying a static high pressure. However, the electromagnetic valve disposed on the discharge passage is manufactured to withstand the instantaneous generation of high pressure during fuel injection, but is not manufactured to withstand static high pressure. For this reason, when static high pressure is applied in the discharge passage, there is a possibility that the components inside the solenoid valve are damaged. Therefore, oil leakage cannot be confirmed by applying a static high pressure.

  As another detection method, the execution of the air leak method and rated operation was verified. The air leak method is a method generally used for confirming the sealing property. However, with this method, even if the sealing performance of the seal tube is broken, the sealing performance cannot be confirmed. On the other hand, in the case of rated operation, oil leakage in the leak passage could be confirmed when the sealing performance was broken by performing the rated operation for 1 hour or more. However, if a new facility for performing rated operation for testing is newly installed, a high cost of tens of millions of yen will occur. Further, the operation for one hour or more exceeds the time that is manufacturable in the production line.

  An object of the present invention is to provide a means for confirming whether or not the sealing performance of a seal tube is maintained without damaging components inside the solenoid valve.

  A fuel injection pump test apparatus according to the present invention is a test apparatus for confirming sealing performance in a fuel injection pump having a plunger pump and an electromagnetic valve that opens and closes communication between a discharge passage and an introduction passage of the plunger pump. The solenoid valve is disposed, and is disposed on the discharge passage so as to cross between the valve block in which a leak passage is formed and the opposed surfaces of the plunger pump and the valve block. A seal tube, and a pressure applying device that applies a high pressure to the liquid injected into the leak passage. The leak passage communicates with an outer surface of the seal tube, and the valve is formed between the opposing surfaces. It reaches the outside of the block.

  The test apparatus includes an image recognition device that detects liquid leaking on the inner surface of the barrel by taking an image of the inner surface of the barrel formed on the plunger pump.

  The test device measures a time until the pressure in the leak passage decreases to a predetermined reference pressure after stopping the application of the high pressure by the pressure application device and a pressure detection device that detects the pressure in the leak passage. A measuring device.

  According to the fuel injection pump test apparatus of the present invention, whether the sealing performance of the seal tube is maintained by checking the presence or absence of liquid leaking in the discharge passage without damaging the components inside the solenoid valve. Can be confirmed.

It is a longitudinal cross-sectional view of the fuel injection pump by which the sealing performance is confirmed by the test apparatus which concerns on 1st Embodiment. It is sectional drawing of the test pump tested by the test apparatus which concerns on 1st Embodiment. It is a partial cutaway perspective view of the plunger pump tested by the testing device concerning a 1st embodiment. 1 is a configuration diagram of a test apparatus according to a first embodiment. It is a block diagram of the test apparatus which concerns on 2nd Embodiment. It is a block diagram of the test apparatus which concerns on 3rd Embodiment.

  FIG. 1 is a longitudinal sectional view of a fuel injection pump 1 whose sealing performance is confirmed by a test apparatus according to the first embodiment. The fuel injection pump 1 has a plunger pump 2, an electromagnetic valve (electromagnetic spill valve) 3, an equal pressure valve 4, and a discharge valve 5. The fuel injection pump 1 also includes an electromagnetic valve block 20 and an isobaric valve holder 30. The electromagnetic valve 3 is disposed in the electromagnetic valve block 20 via the insert piece 31. The equal pressure valve 4 and the discharge valve 5 are disposed between the electromagnetic valve block 20 and the equal pressure valve holder 30. The solenoid valve block 20 and the equal pressure valve holder 30 constitute a valve block that houses the solenoid valve 3, the equal pressure valve 4, and the discharge valve 5.

  The fuel injection pump 1 includes an inlet port 6a, an introduction passage 6b, a pump chamber 6c, and a discharge passage 6d. The inlet port 6 a is open to the outside of the plunger pump 2. The introduction passage 6b reaches the solenoid valve 3 from the inlet port 6a. The pump chamber 6 c is a space for storing fuel and is formed in the plunger pump 2. The discharge passage 6d extends from the pump chamber 6c to the outside of the equal pressure valve holder 30 via the solenoid valve 3, the equal pressure valve 4, and the discharge valve 5.

  The fuel injection pump 1 includes a seal tube 14 for ensuring the sealing performance of the discharge passage 6d. The seal tube 14 is a cylindrical member, and is a discharge passage 6d so as to cross between the opposing surfaces of the plunger pump 2 and the solenoid valve block 20 (the seal surface F10 of the barrel 12 and the seal surface F20 of the solenoid valve block 20). Is placed on top.

  The plunger pump 2 includes a plunger 11, a barrel 12, and a pump body 13. The plunger 11 is disposed in the barrel 12. The pump body 13 is fixed to the barrel 12. The upper surface (seal surface F10) of the plunger pump 2 is the upper surface of the barrel 12.

  The electromagnetic valve (electromagnetic spill valve) 3 is a valve that opens and closes communication between the discharge passage 6 d and the introduction passage 6 b of the plunger pump 2. The solenoid valve 3 is disposed on the discharge passage 6d, and the discharge passage 6d is not blocked regardless of the switching of the solenoid valve 3. The electromagnetic valve 3 is located at the end of the introduction passage 6b, and the communication and blocking between the introduction passage 6b and the introduction passage 6b are switched according to the switching of the electromagnetic valve 3.

  The discharge valve 5 opens and closes the discharge passage 6d, and opens the discharge passage 6d when the pressure on the downstream side of the discharge valve 5 becomes greater than the pressure on the upstream side of the discharge valve 5 by a predetermined first differential pressure or more. . In other cases, the discharge valve 5 closes the discharge passage 6d.

  The equal pressure valve 4 is a valve that opens and closes the valve body of the discharge valve 5, and when the pressure on the upstream side of the discharge valve 5 becomes larger than the pressure on the downstream side of the discharge valve 5 by a predetermined second differential pressure or more, The discharge passage 6d is opened by opening the valve body 5. In other cases, the equal pressure valve 4 closes the valve body of the discharge valve 5. For example, when the pressure on the upstream side of the discharge valve 5 becomes high, the isobaric valve 4 opens so as to release the high pressure.

  The operation of the fuel injection pump 1 will be described. The operation of the fuel injection pump 1 is controlled by a cam (not shown) that drives the plunger 11 and the electromagnetic valve 3.

  When the solenoid valve 3 opens the communication between the discharge passage 6d and the introduction passage 6b, the fuel is sucked into the pump chamber 6c or discharged from the pump chamber 6c as the plunger 11 moves up and down by the cam described above. . Here, since the pressure on the upstream side of the discharge valve 5 does not increase the pressure on the downstream side of the discharge valve 5 by more than the first differential pressure, the discharge valve 5 remains closed.

  When the electromagnetic valve 3 receives an open signal from an ECU (not shown), the communication between the discharge passage 6d and the introduction passage 6b is closed. When the introduction passage 6b is closed, the fuel is compressed in the pump chamber 6c as the plunger 11 rises. As a result, the pressure on the upstream side of the discharge valve 5 becomes larger than the pressure on the downstream side of the discharge valve 5 by the first differential pressure, and the discharge valve 5 is opened. When the discharge valve 5 is opened, the fuel is discharged from the fuel injection pump 1 along the discharge passage 6 to the outside. Thereafter, when the electromagnetic valve 3 receives a closing signal from an ECU (not shown), the communication between the discharge passage 6d and the introduction passage 6b is opened. As a result, the pressure in the discharge passage 6d decreases, and the discharge valve 5 is closed again.

  FIG. 2 is a cross-sectional view of the test pump 50 to be tested by the test apparatus 100 according to the first embodiment. The test pump 50 is different from the fuel injection pump 1 in the following points, and has the same configuration as the fuel injection pump 1 in other points. The test pump 50 does not include the equal pressure valve 4 and the discharge valve 5. In the test pump 50, the isobaric valve holder 30 of the fuel injection pump 1 is replaced with a block jig 40.

  In the test pump 50, the electromagnetic valve block 20 and the block jig 40 constitute a valve block. A leak passage 7 is formed in the valve block of the test pump 50. The leak passage 7 reaches the outside of the block jig 40 from between the seal surfaces F10 and F20 between the plunger pump 2 and the electromagnetic valve block 20. The leak passage 7 includes a main leak passage 7 a formed in the electromagnetic valve block 20 and a sub leak passage 7 b formed in the block jig 40. The main leak passage 7a is formed from the lower surface (seal surface F20) of the electromagnetic valve block 20 to the upper surface of the electromagnetic valve block 20. The auxiliary leak passage 7b is formed from the lower surface of the block jig 40 to the upper surface of the block jig 40, and communicates with the main leak passage 7a. The isobaric valve holder 30 is not formed with a leak passage. Therefore, in the fuel injection pump 1, the main leak passage 7 a is closed by the sub valve block 30.

  FIG. 3 is a partially cut perspective view of the plunger pump 2 to be tested by the test apparatus 100 according to the first embodiment. On the upper surface (seal surface F10) of the plunger pump 2, an inner O-ring 8 and an outer O-ring 9 are arranged along the radial direction of the discharge passage 6d. In the inner O-ring 8, the upper surface of the plunger pump 2 is recessed. Therefore, an annular space S is formed outside the seal tube 14 and between the upper surface (seal surface F10) of the plunger pump 2 and the lower surface (seal surface F20) of the solenoid valve block 20. The main leak passage 7 a formed in the electromagnetic valve block 20 opens into the annular space S and communicates with the outer surface of the seal tube 14.

  FIG. 4 is a configuration diagram of the test apparatus 100 according to the first embodiment. The test apparatus 100 includes a test pump 50 and a pressure application device 60. The pressure application device 60 is a device that applies a high pressure to the liquid injected into the leak passage 7. The pressure application device 60 is, for example, a pressure pump, and this pressure pump is connected to the inlet port 7 c of the leak passage 7 using a pipe 61. The liquid injected into the leak passage 7 is fuel oil that is used when the fuel injection pump 1 is operated, but other liquids may be used.

  When the pressure application device 60 operates, the pressure of the liquid in the leak passage 7 becomes high. When the seal tube 14 is broken and the sealing performance is broken, the leak passage 7 communicates with the discharge passage 6d. For this reason, when the pressure of the liquid in the leak passage 7 becomes high when the sealing performance is broken, the liquid in the leak passage 7 leaks into the discharge passage 6d. The leaked liquid also flows into the pump chamber 6c. For this reason, the liquid leaking into the discharge passage 6d can be confirmed by visually recognizing the pump chamber 6c. Here, by removing the plunger 11 in the plunger pump 2, the pump chamber 6c can be exposed to the outside. Therefore, based on whether or not the liquid is visually recognized in the pump chamber 6c, it can be confirmed whether or not the sealing performance is broken.

  FIG. 5 is a configuration diagram of a test apparatus 200 according to the second embodiment. The test apparatus 200 further includes an image recognition apparatus 70 in addition to the components of the test apparatus 100 according to the first embodiment. The image recognition device 70 is a device that detects liquid leaking on the inner surface of the barrel by taking an image of the inner surface of the barrel (pump chamber 6c) formed in the plunger pump 2.

  When the sealing performance is not broken, the image in the pump chamber 6c is the same as the image at the time of manufacturing the pump chamber 6c. On the other hand, when the sealing property is broken, the liquid leaks into the pump chamber 6c, so the image of the pump chamber 6c is different from the image at the time of manufacturing the pump chamber 6c. For this reason, the image recognition device 70 confirms whether or not the sealing performance is broken by comparing the image at the time of manufacture of the pump chamber 6c with the image of the pump chamber 6c after the test by the pressure application device 60. be able to.

  FIG. 6 is a configuration diagram of a test apparatus 300 according to the third embodiment. The test apparatus 100 includes a test pump 50, a pressure application device 60, a pressure detection device 80, and a measurement device 90. The pressure detection device 80 is a device that detects the pressure in the leak passage 7. The measuring device 90 is a device that measures the time until the pressure in the leak passage 7 decreases to a predetermined reference pressure after the application of high pressure by the pressure applying device 60 is stopped.

  When the sealing performance is not broken, the pressure in the leak passage 7 does not greatly decrease even after the application of high pressure is stopped. On the other hand, since the liquid leaks from the leak passage 7 to the discharge passage 6d when the sealing performance is broken, the pressure in the leak passage 7 decreases with time. In this case, the pressure in the leak passage 7 decreases to the reference pressure in a relatively short time. For this reason, based on the time required for the pressure drop measured by the measuring device 90, it can be confirmed whether the sealing performance is broken.

  The first to third embodiments have the following effects due to the above-described configuration.

  The test apparatus 100, 200, 300 according to each of the first to third embodiments includes a plunger pump 2 and a fuel injection having an electromagnetic valve 3 that opens and closes communication between the discharge passage 6d and the introduction passage 6b of the plunger pump 2. In the pump 1, it is a test apparatus for confirming the sealing performance. In each of the test apparatuses 100, 200, and 300, the solenoid valve 3 is disposed, a valve block (20, 40) in which a leak passage 7 is formed, the plunger pump 2, and the valve block (20, 40) and a sealing tube 14 disposed on the discharge passage 6d so as to cross between the sealing surfaces F10 and F20, a pressure applying device 60 for applying a high pressure to the liquid injected into the leak passage 7, It has. The leak passage 7 communicates with the outer surface of the seal tube 14 and reaches the outside of the valve block (20, 40) from between the seal surfaces F10, F20.

  Without applying high pressure to the inside of the solenoid valve 3, high pressure is applied to the seal tube 14 disposed on the discharge passage 6d so as to cross the seal surfaces F10, F20 between the plunger pump 2 and the valve block (20, 40). . When the seal tube 14 is broken, the liquid leaks into the discharge passage 6d.

  According to the test apparatus 100, 200, 300 according to each of the first to third embodiments, by checking the presence or absence of liquid leaking in the discharge passage 6d without damaging the components inside the electromagnetic valve 3, It can be confirmed whether or not the sealing performance of the seal tube 14 is maintained.

  The test apparatus 200 according to the second embodiment detects an image of a barrel inner surface (pump chamber 6c) formed in the plunger pump 2 to detect liquid leaking on the barrel inner surface. It has.

  Since the presence or absence of liquid leaking in the discharge passage 6d is performed by the machine, it is possible to unify the determination criteria for confirming whether or not the sealing performance is maintained.

  The test apparatus 300 according to the third embodiment includes a pressure detection device 80 that detects the pressure in the leak passage 7 and the pressure in the leak passage 7 after the pressure application device 60 stops applying the high pressure. And a measuring device 90 that measures the time until the pressure falls to the reference pressure.

  Since it is not necessary to directly detect the liquid leaking into the discharge passage 6d, it is possible to simplify the check operation of the sealing performance.

  The present embodiment can employ the following modified configuration.

  In the first to third embodiments, a block jig 40 having a secondary leak passage 7b is used instead of the isobaric valve holder 30 in order to confirm the sealing performance. Instead, a leak passage that communicates with the main leak passage 7a and opens to the outside may be formed in the sub valve block 30. This leak passage is formed separately from the discharge passage 6d. In this case, the isobaric valve holder 30 can be used as it is instead of the block jig 40 in order to confirm the sealing performance.

DESCRIPTION OF SYMBOLS 1 Fuel injection pump 2 Plunger pump 3 Solenoid valve 6b Introduction passage 6d Discharge passage 7 Leak passage 14 Seal tube 20 Solenoid valve block 30 Isobaric valve holder 40 Block jig F10 (Surface of plunger pump facing solenoid valve block) Seal surface F20 ( Electromagnetic valve block facing surface against plunger pump) Seal surface 60 Pressure application device 70 Image recognition device 80 Pressure detection device 90 Measuring device 100, 200, 300 Test device

Claims (3)

In a fuel injection pump having a plunger pump and an electromagnetic valve that opens and closes communication between a discharge passage and an introduction passage of the plunger pump, a test device for confirming sealing performance,
A valve block in which the solenoid valve is disposed and a leak passage is formed;
A seal tube disposed on the discharge passage so as to cross between the opposed surfaces of the plunger pump and the valve block;
A pressure application device that applies a high pressure to the liquid injected into the leak passage,
The fuel injection pump test apparatus, wherein the leak passage communicates with an outer surface of the seal tube and extends from between the opposing surfaces to the outside of the valve block.   2. The fuel injection pump testing device according to claim 1, further comprising an image recognition device that detects liquid leaking on the inner surface of the barrel by capturing an image of the inner surface of the barrel formed on the plunger pump. 3. A pressure detection device for detecting pressure in the leak passage;
The fuel injection according to claim 1, further comprising: a measuring device that measures a time until the pressure in the leak passage decreases to a predetermined reference pressure after stopping the application of the high pressure by the pressure applying device. Pump testing equipment.

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