JP3879602B2 - Liquid level position adjustment device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a liquid level position adjusting device.
[0002]
[Prior art]
For example, a fuel pump applied to an internal combustion engine (hereinafter, the internal combustion engine is referred to as an “engine”) is inspected as to whether a flow rate of fuel discharged after assembly satisfies a predetermined performance. Conventionally, when measuring the amount of fuel discharged from a fuel pump, the fuel pump is immersed in a test fluid stored in a test tank. And the flow volume of the fuel discharged | emitted from the fuel pump is measured by operating the fuel pump immersed in the test fluid.
[0003]
By the way, at the time of inspection of the fuel pump, it is necessary to keep the liquid level position of the test fluid constant in order to keep the operating condition constant. Therefore, for example, as shown in FIG. 3, the test fluid stored in the tank 101 is supplied to the test tank 102 by the circulation pump 100, and the test fluid is overflowed from the test tank 102, so that the liquid level position of the test fluid is fixed. Is controlling.
[0004]
[Problems to be solved by the invention]
However, when the liquid level position of the test fluid is controlled by overflow, the test fluid is heated as the circulation pump 100 generates heat. The test tank 102 is open to the atmosphere. As the test fluid, a fluid whose physical properties are similar to those of fuel (for example, gasoline or light oil) applied to the fuel pump 103 is used. For this reason, the heated test fluid tends to volatilize, and the volatilized test fluid diffuses around the test tank 102, thus deteriorating the surrounding environment.
[0005]
Further, the test fluid decreases with the volatilization of the test fluid, and the oxidation of the test fluid is promoted by contact with oxygen in the atmosphere. As a result, there is a problem that it is necessary to frequently replenish and renew the test fluid.
[0006]
Therefore, the object of the present invention is that power for adjusting the liquid level of the test fluid is unnecessary, and volatilization due to heating of the test fluid, deterioration of the environment due to volatilization, and oxidation of the test fluid due to contact with oxygen are prevented. An object of the present invention is to provide a liquid level position adjusting device.
[0007]
[Means for Solving the Problems]
According to the liquid level position adjusting apparatus of the first or fourth aspect of the present invention, the liquid level position adjusting device includes a fluid tank in which a test fluid is stored and a storage portion in which a test target is stored. The fluid tank and the accommodating portion are connected by a first connecting portion, and an inert gas is supplied from the gas supply means to the fluid tank and the accommodating portion. The port at the end of the first connecting portion that connects the fluid tank and the containing portion opens to a predetermined position that is set as the liquid level position. Therefore, when the liquid level of the storage unit becomes lower than a predetermined position, the port is opened and the inert gas flows from the storage unit into the fluid tank. As a result, the test fluid stored in the fluid tank flows to the accommodating portion via the second connection portion. On the other hand, when the liquid level of the storage unit becomes higher than a predetermined position, the port is closed and the inert gas does not flow from the storage unit to the fluid tank. As a result, the pressure in the storage portion increases, and the test fluid in the storage portion flows to the fluid tank via the second connection portion. As a result, the position of the liquid level of the test fluid stored in the storage unit is controlled by the balance of the pressure of the inert gas in the storage unit and the fluid tank communicated by the first connection unit. Therefore, power for controlling the liquid level of the test fluid is not required, and it is possible to prevent the temperature of the test fluid from rising, the test fluid volatilizing due to the temperature rise, and the deterioration of the surrounding environment due to the test fluid volatilization. .
[0008]
Moreover, the liquid level of the test fluid in the storage unit can be quickly controlled by adjusting the liquid level by the pressure between the storage unit and the fluid tank. Further, the storage portion is sealed, and an inert gas is supplied to the storage portion and the fluid tank. Therefore, contact with the atmosphere can be prevented, and oxidation of the test fluid can be prevented. Further, the inspection object in the housing portion is inspected with being pressurized to some extent by the inert gas. Therefore, it is possible to easily form an environment under a predetermined pressure close to a state where the inspection target is actually applied. Therefore, the inspection accuracy of the inspection object can be increased.
[0009]
According to the liquid level position adjusting apparatus of the second aspect of the present invention, the inert gas is nitrogen. Nitrogen is inexpensive among inert gases. Nitrogen is easy to store, for example, by liquefying. Furthermore, a deoxygenation atmosphere can be formed inside the accommodating part by filling the accommodating part with nitrogen. Therefore, safety at the time of inspection is increased, and peripheral facilities can be simplified.
[0010]
According to the liquid level position adjusting apparatus of the third aspect of the present invention, the second connecting portion has opening / closing means for opening / closing the flow of the test fluid. For example, when the test fluid in the container is returned to the fluid tank after the inspection of the test object is completed, it is necessary to prevent the test fluid from flowing from the fluid tank to the container. Accordingly, unnecessary opening of the test fluid can be prevented by the opening / closing means.
According to the liquid level position adjusting apparatus of the fifth aspect of the present invention, the liquid level position of the test fluid is set below the vibration sensor. Thereby, it is prevented that a vibration sensor and a test fluid contact. Therefore, the inspection accuracy of the inspection object can be increased.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a plurality of examples showing embodiments of a liquid level position adjusting device according to the present invention will be described with reference to the drawings.
(First embodiment)
As shown in FIG. 1, the liquid level position adjusting device according to the first embodiment of the present invention is applied to a flow rate inspection system 1 for inspecting the flow rate of a test fluid discharged from a fuel pump 10 to be inspected.
[0012]
The flow rate inspection system 1 mainly includes a storage unit 20, a fluid tank 30, a first connection unit 40, a second connection unit 50, a nitrogen supply unit 60 as a gas supply unit, and a measurement unit 70. The liquid level position adjusting device includes a storage unit 20, a fluid tank 30, a first connection unit 40, a second connection unit 50, and a nitrogen supply unit 60. The accommodating part 20 accommodates the fuel pump 10 to be inspected. The fuel pump 10 has an impeller (not shown) that is driven to rotate by a motor (not shown). When electric power is supplied to the terminal 11, the motor rotates the impeller. As a result, fuel is sucked from the fuel inlet 12 and discharged from the fuel outlet 13.
[0013]
The accommodating portion 20 includes a tank 21 and a cover 22. The tank 21 can store a test fluid therein. The test fluid is a test fluid whose physical properties such as viscosity and density approximate to the actual fuel (for example, gasoline or light oil) applied to the fuel pump 10 as described above. The cover 22 is installed above the tank 21 in the vertical direction. A seal member 23 is installed between the tank 21 and the cover 22, and a space formed by the tank 21 and the cover 22 is sealed by the seal member 23.
[0014]
The fuel pump 10 is accommodated in the accommodating portion 20. A discharge pipe 24 communicating with the measurement unit 70 is connected to the fuel pump 10 accommodated in the accommodation unit 20. The test fluid discharged from the fuel pump 10 flows out to the measuring unit 70 via the discharge pipe 24. The fuel pump 10 is connected to the power supply unit 2, and electric power necessary for operation is supplied from the power supply unit 2 to the fuel pump 10. Further, a vibration sensor 3 is attached to the fuel pump 10, and the vibration sensor 3 detects vibration of the fuel pump 10 during operation.
[0015]
A test fluid is stored in the fluid tank 30. The fluid tank 30 and the storage unit 20 communicate with each other via the first connection unit 40 and the second connection unit 50. The first connection part 40 includes a first series pipe 41 and a first on-off valve 42. The first connection part 40 has a port 43 in which one end of the first continuous pipe 41 opens into the housing part 20. The other end of the first series pipe 41 communicates with the fluid tank 30. The first opening / closing valve 42 opens and closes the first connection portion 41. The 2nd connection part 50 has the 2nd communication pipe 51 and the 2nd on-off valve 52 as an on-off means. The second communication pipe 51 communicates the accommodating portion 20 and the fluid tank 30 below the port 43. The second on-off valve 52 opens and closes the second communication pipe 51.
[0016]
The port 43 is formed in the tank 21. The position where the port 43 is open corresponds to a predetermined position on the liquid level of the test fluid supplied to the storage unit 20. That is, the liquid level position of the test fluid supplied to the storage unit 20 is set in advance, and the port 43 opens at the set liquid level position. The liquid level position of the test fluid stored in the fluid tank 30 is located above a predetermined liquid level position of the test fluid supplied to the port 43, that is, the storage unit 20. The end of the first series pipe 41 on the fluid tank 30 side is located above the port 43.
[0017]
The nitrogen supply unit 60 includes a storage tank 61, a supply pipe unit 62, and a control valve 63. The supply pipe unit 62 communicates the storage tank 61 and the storage unit 20. The control valve 63 controls the flow of nitrogen in the supply pipe unit 62. For example, liquid nitrogen is stored in the storage tank 61, and nitrogen whose pressure is adjusted by controlling the control valve 63 is supplied to the storage unit 20. The end of the supply pipe 62 on the side opposite to the storage tank communicates above the port 43.
[0018]
The measuring unit 70 measures the pressure and flow rate of the test fluid discharged from the fuel pump 10. The measurement unit 70 has a measurement passage portion 71, and a control valve 72, a pressure sensor 73, and a flow rate sensor 74 are installed in the measurement passage portion 71. The measurement passage portion 71 has one end communicating with the discharge pipe 24 and the other end communicating with the fluid tank 30. The control valve 72 controls the flow of the test fluid in the measurement passage portion 71. The test fluid discharged from the fuel pump 10 flows into the measurement passage portion 71 via the discharge pipe 24, and flows out to the fluid tank 30 through the pressure sensor 73, the flow rate sensor 74 and the control valve 72. As a result, the test fluid stored in the fluid tank 30 circulates through the storage unit 20, the fuel pump 10, the discharge pipe 24, and the measurement unit 70.
[0019]
Next, the inspection of the fuel pump 10 using the flow rate inspection system 1 having the above configuration will be described.
The fuel pump 10 is accommodated in the accommodating portion 20. The container 20 can be separated into a tank 21 and a cover 22. The housing part 20 is provided with a holding part (not shown), and the fuel pump 10 is supported by the holding part. By connecting the tank 21 and the cover 22, the fuel pump 10 is held inside the housing portion 20. When the fuel pump 10 is held inside the housing portion 20, the discharge pipe 24, the power connector 25, and the vibration sensor 3 provided inward from the cover 22 are connected to the fuel pump 10. The discharge pipe 24 is connected to the fuel outlet 13 of the fuel pump 10. The power connector 25 is connected to the terminal 11 of the fuel pump 10. The vibration sensor 3 is attached to a predetermined position of the fuel pump 10. At this time, the first on-off valve 42, the second on-off valve 52, and the control valve 63 are closed. Therefore, the test fluid is not supplied to the storage unit 20. Further, since the tank 21 and the cover 22 are sealed by the seal member 23, the inside of the accommodating portion 20 is in a sealed state.
[0020]
When the housing of the fuel pump 10 in the housing portion 20 is completed, the control valve 63 is opened, and the nitrogen stored in the storage tank 61 is supplied to the inside of the housing portion 20 sealed at a constant pressure. For example, by setting the pressure of nitrogen supplied from the storage tank 61 to the storage unit 20 to be higher than the inside of the storage unit 20, the nitrogen flows into the storage unit 20 without power by opening the control valve 63. At this time, the first opening / closing valve 42 is opened, and a part of the nitrogen flowing into the housing portion 20 is also supplied to the fluid tank 30 via the first series pipe 41. By supplying a part of nitrogen to the fluid tank 30, the test fluid in the fluid tank 30 is pressurized by nitrogen.
[0021]
When the supply of nitrogen is started, the second on-off valve 52 is opened. As a result, the test fluid stored in the fluid tank 30 flows into the storage unit 20 via the second communication pipe 51. The liquid level position of the test fluid stored in the fluid tank 30 is higher than the port 43 that opens to the storage unit 20. Therefore, the liquid level position of the test fluid supplied to the storage unit 20 rises in the storage unit 20 so as to be the same position in the storage unit 20 and the fluid tank 30. On the other hand, the port 43 opens at a predetermined position that is set in advance as a liquid level position of the test fluid supplied to the storage unit 20. Therefore, when the liquid level position of the test fluid in the storage unit 20 rises, the port 43 is blocked by the test fluid before the liquid level position of the test fluid becomes the same in the storage unit 20 and the fluid tank 30. As a result, the communication between the container 20 and the fluid tank 30 is blocked, and the inflow of nitrogen into the fluid tank 30 is blocked. Thereby, the supply of the test fluid from the fluid tank 30 to the storage unit 20 is stopped.
[0022]
At this time, since the control valve 63 remains open, the supply of nitrogen from the storage tank 61 to the storage unit 20 is continued. Therefore, the pressure inside the storage unit 20 becomes higher than the pressure inside the fluid tank 30. As a result, the test fluid in the storage unit 20 flows out to the fluid tank 30, and the liquid level position of the test fluid in the storage unit 20 decreases. On the other hand, when the liquid level position of the test fluid in the storage unit 20 is lowered to below the port 43, the port 43 is opened again, so that the fluid tank 30 is connected from the storage unit 20 via the port 43 and the first communication pipe 41. Again, nitrogen is supplied. As a result, the test fluid in the fluid tank 30 is supplied to the storage unit 20 via the second communication pipe 51.
[0023]
According to the above procedure, when the liquid level position of the test fluid in the container 20 becomes higher than the port 43, the test fluid flows out from the container 20 to the fluid tank 30, and when the liquid surface position becomes lower than the port 43, the test fluid is fluid The storage unit 20 is replenished from the tank 30. Thereby, the liquid level position of the test fluid in the accommodating part 20 is adjusted uniformly. The position of the port 43 is below the position where the vibration sensor 3 is installed, and the fuel pump 10 is immersed in the test fluid only in the vicinity of the fuel inlet 12.
[0024]
When the liquid level position of the test fluid in the storage unit 20 reaches a predetermined position, power is supplied from the power supply unit 2 to the fuel pump 10. As a result, the fuel pump 10 starts operation, pressurizes the test fluid sucked from the fuel inlet 12, and discharges it from the fuel outlet 13. At this time, the control valve 72 of the measuring unit 70 is opened, and the test fluid discharged from the fuel pump 10 flows into the measuring unit 70 via the discharge pipe 24. The pressure and flow rate of the discharged test fluid are measured by the pressure sensor 73 and the flow rate sensor 74. The test fluid whose pressure and flow rate are detected is returned to the fluid tank 30 via the measurement passage portion 71. Further, the vibration of the fuel pump 10 during operation is detected by the vibration sensor 3. Thereby, the inspection of the fuel pump 10 is executed.
[0025]
With the operation of the fuel pump 10, the test fluid in the storage unit 20 is discharged to the measurement unit 70, so the test fluid in the storage unit 20 decreases. However, since the test fluid is replenished from the fluid tank 30 when the liquid level position of the test fluid in the container 20 is lowered as described above, even when the fuel pump 10 is operating, the test fluid in the container 20 The liquid level position is kept constant.
[0026]
When the inspection of the fuel pump 10 is completed, the supply of power to the fuel pump 10 is stopped. And the 1st on-off valve 42 of the 1st connection part 40 is closed. Thereby, the flow of nitrogen from the container 20 to the fluid tank 30 is blocked. Since the control valve 63 is opened, the supply of nitrogen to the storage unit 20 is continued. Therefore, the pressure of the storage unit 20 increases, and the liquid level position of the test fluid in the storage unit 20 decreases. In other words, the test fluid supplied to the storage unit 20 is returned to the fluid tank 30. When most of the test fluid in the storage unit 20 is returned to the fluid tank 30, the opening degree of the control valve 63 is changed and higher pressure nitrogen is supplied to the storage unit 20. As a result, the test fluid remaining in the storage unit 20 and the second communication pipe 51 is almost completely returned to the fluid tank 30 by the pressure of nitrogen. When the return of the test fluid from the storage unit 20 to the fluid tank 30 is completed, the second on-off valve 52 is shut off, and the flow of the test fluid from the fluid tank 30 to the storage unit 20 is shut off. Further, when the reflux of the test fluid is completed, the control valve 63 is closed, and the supply of nitrogen from the storage tank 61 to the storage unit 20 is also stopped.
[0027]
When the above procedure is completed, the cover 22 is separated from the tank 21 and the fuel pump 10 accommodated in the accommodating portion 20 is taken out. Then, the fuel pump 10 to be inspected next is accommodated in the accommodating portion 20 again. In the above procedure, since the test fluid is recirculated from the container 20 to the fluid tank 30 with the first opening / closing valve 42 closed, the nitrogen in the fluid tank 30 is pressurized. Therefore, the test fluid in the fluid tank 30 is stored in a state of being biased by nitrogen. Therefore, when the second on-off valve 52 is opened at the next inspection, the test fluid in the fluid tank 30 is quickly supplied to the storage unit 20.
[0028]
As described above, in the first embodiment, the liquid level position of the test fluid in the storage unit 20 is controlled by the nitrogen pressure balance between the storage unit 20 and the fluid tank 30. Therefore, for example, power such as a pump is not required to adjust the liquid level position of the test fluid, the equipment is not complicated, and the test fluid is prevented from being heated. Therefore, it is possible to prevent a decrease in the test fluid and deterioration of the surrounding environment due to volatilization. Further, by controlling the liquid level position by the pressure balance of nitrogen, the response of replenishment and reflux of the test fluid to the change in the liquid level position is enhanced, and a constant liquid level position can always be maintained.
[0029]
Further, in this embodiment, the test fluid circulates in the sealed storage unit 20, measurement unit 70, and fluid tank 30. Further, nitrogen is supplied to the storage unit 20 and the fluid tank 30. This reduces the chance that the test fluid will come into contact with oxygen in the atmosphere and prevents oxidation. Therefore, deterioration of the test fluid can be prevented and the life of the test fluid can be extended.
[0030]
Furthermore, in this embodiment, an oxygen-deficient atmosphere is easily formed in the vicinity of the terminal 11 of the fuel pump 10 by supplying nitrogen into the accommodating portion 20. Therefore, safety when the fuel pump 10 is energized can be improved. Further, by supplying nitrogen to the inside of the housing part 20, the inside of the housing part 20 is pressurized to a constant pressure. Therefore, an environment close to the actual environment where the fuel pump 10 is used can be easily reproduced. Therefore, the inspection accuracy of the fuel pump 10 can be increased. Furthermore, by supplying nitrogen to the inside of the housing part 20, entry of foreign matter such as air or dust from the outside can be prevented.
[0031]
(Second embodiment)
FIG. 2 shows a flow rate inspection system to which the liquid level position adjusting device according to the second embodiment of the present invention is applied. Components that are substantially the same as those of the first embodiment are denoted by the same reference numerals, and description thereof is omitted.
In the second embodiment, the configuration of the accommodating portion 20 is different from that of the first embodiment. In the second embodiment, the tank 21 accommodates the fuel inlet 12 side of the fuel pump 10, and the cover 22 accommodates the fuel outlet 13 side of the fuel pump 10. That is, in the first embodiment, the fuel pump 10 is accommodated in the space formed by the tank 21 and the cover 22, whereas in the second embodiment, the tank 21 and the cover 22 each accommodate the fuel pump 10. A space to do this is formed.
[0032]
A seal member 26 is installed between the tank 21 and the fuel pump 10, and the tank 21 and the fuel pump 10 are sealed. The supply pipe 62 of the air supply unit 60 is also communicated with the inside of the tank 21. The tank 21 communicates with the first continuous pipe 41 of the first connection part 40 and the second communication pipe 51 of the second connection part 50. Therefore, the liquid level position of the test fluid is kept constant on the fuel inlet 12 side of the fuel pump 10.
On the other hand, a seal member 27 is installed between the cover 22 and the fuel pump 10, and the cover 22 and the fuel pump 10 are sealed. The cover 22 is provided with a discharge pipe 24 that communicates with the measurement passage section 71 of the measurement section 70.
[0033]
A predetermined interval is formed between the tank 21 and the cover 22. That is, the fuel pump 20 is formed with a portion that is not accommodated in the tank 21 and the cover 22 and is exposed to the outside. The vibration sensor 3 is attached to a portion of the fuel tank 10 exposed to the outside. Thereby, the vibration sensor 3 can be easily attached to the fuel pump 10.
[0034]
In the second embodiment, since the tank 21 and the cover 22 accommodate the fuel pump 10 respectively, a part of the fuel pump 10 is exposed to the outside. Therefore, the vibration sensor 3 can be easily attached. Further, since the vibration sensor 3 does not come into contact with the test fluid, the vibration detection accuracy by the vibration sensor 3 can be increased.
[0035]
In the plurality of embodiments of the present invention described above, the example in which the fuel pump is applied as the inspection target has been described. However, for example, a fuel injection pump or an injector can be used as long as the test fluid is used at the time of inspection and the liquid level position of the test fluid needs to be adjusted. Moreover, although the example which uses nitrogen as an inert gas was demonstrated, you may use noble gases, such as argon, or a carbon dioxide, for example.
[Brief description of the drawings]
FIG. 1 is a schematic diagram showing a fuel pump flow rate inspection system to which a liquid level position adjusting device according to a first embodiment of the present invention is applied.
FIG. 2 is a schematic diagram showing a fuel pump flow rate inspection system to which a liquid level position adjusting device according to a second embodiment of the present invention is applied.
FIG. 3 is a schematic view showing a flow rate inspection system for a conventional fuel pump.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 3 Vibration sensor 10 Fuel pump 12 Fuel inlet 13 Fuel outlet 20 Storage part 30 Fluid tank 40 First connection part 43 Port 50 Second connection part 52 Second on-off valve (open / close means)
60 Nitrogen supply part (gas supply means)

Claims (5)

An adjustment device that adjusts the liquid level of a test fluid into which a test object is immersed to a predetermined position,
A fluid tank in which a test fluid is stored, and a liquid level of the stored test fluid is higher than the predetermined position;
A test fluid is supplied from the fluid tank, and an accommodating portion capable of sealingly accommodating the test object partially immersed in the supplied test fluid;
A first connecting portion that communicates the accommodating portion with the fluid tank, has a port at an end on the accommodating portion side, and the port is open at the predetermined position;
A second connection portion that communicates the storage portion and the fluid tank below the predetermined position;
A gas supply means capable of supplying an inert gas to the fluid tank via the storage portion and the first connection portion;
An apparatus for adjusting a liquid level, comprising: The liquid level position adjusting device according to claim 1, wherein the inert gas is nitrogen. 3. The liquid level position adjusting device according to claim 1, wherein the second connection portion has an opening / closing means for opening and closing a flow of a test fluid between the storage portion and the fluid tank. 4. The liquid level position adjusting device according to claim 1, further comprising a vibration sensor that is attached to the inspection object and detects vibration of the inspection object. The liquid level position adjusting device according to claim 4, wherein the predetermined position is set below the vibration sensor.

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