JP2018066686A - Method of testing liquid pressure device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem in which a leakage test need to be conducted on high-pressure system piping and low-pressure system piping individually in a conventional method of testing a liquid pressure test.SOLUTION: A method of testing a liquid pressure device comprises: applying measurement pressure for detecting a leak in high-pressure system piping to the high-pressure system piping in a state in which a pressure reduction valve connecting the high-pressure system piping and low-pressure system piping together is closed; calculating, as high-pressure system differential pressure, the total value of differences between the measurement pressure and in-system pressure obtained from a plurality of pressure sensors provided to the high-pressure system piping respectively; calculating, as drain system pressure, the value obtained by multiplying leak pressure, obtained from a pressure sensor provided to a drain system by a preset coefficient; and inspecting a leak in both the high-pressure system piping and low-pressure system piping based upon the difference between the high-pressure system differential pressure and the drain system pressure.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a test method for a hydraulic device, for example, a test method for a hydraulic device having a high-pressure system pipe and a low-pressure system pipe.

In the brake actuator, a hydraulic device (for example, a pressure chamber) that increases or decreases the pressure of the fluid is used. In this pressure chamber, it is tested whether the fluid leakage is within a predetermined range of preset values. An example of this pressure chamber test method is described in Patent Document 1.
In the pressure chamber test method described in Patent Document 1, pressure characteristics in a pressure chamber determined as a good product are measured and stored as reference data, and the pressure applied to the pressure chamber to be tested is gradually increased. A test for increasing the pressure chamber is performed, and the quality of the pressure chamber is determined by comparing the test result with the reference data.

Japanese National Patent Publication No. 10-507512

  However, the pressure chamber has a high-pressure system pipe that allows a high applied pressure and a low-pressure system pipe that allows a lower applied pressure than the high-pressure pipe. If the pressure which tests the leak of a high voltage | pressure system piping is applied to this low voltage | pressure system piping, a low voltage | pressure system piping will be destroyed. Therefore, in a pressure chamber having a high pressure system pipe and a low pressure system pipe, it is necessary to perform separate tests on the leakage of the high pressure system pipe and the low pressure system pipe. Even if the technique described in Patent Document 1 is used, the high-pressure system piping and the low-pressure system piping must be tested separately, which causes a problem that the test time becomes long.

  The present invention has been made in view of the above circumstances, and aims to shorten the test time for the pressure chamber.

  A test method for a hydraulic apparatus according to an aspect of the present invention includes a high pressure system pipe in which a high allowable pressure is set, and a low pressure system pipe in which an allowable pressure is set lower than the high pressure system pipe, A method of testing a hydraulic apparatus in which a drain system constituted by a low-pressure system pipe is integrated into one system, wherein the high-pressure system is closed with a pressure reducing valve connecting the high-pressure system pipe and the low-pressure system pipe closed. A measurement pressure for detecting leakage in the high-pressure system pipe is applied to the pipe, and the difference between the measurement pressure and the total value of the system pressure obtained from each of the plurality of pressure sensors provided in the high-pressure system pipe The pressure is calculated as a high system differential pressure, the leakage pressure obtained from the pressure sensor provided in the drain system is detected, and a value obtained by multiplying the leakage pressure by a preset coefficient is calculated as the drain system pressure, When the first judgment value obtained by subtracting the drain system pressure from the high-pressure system differential pressure is larger than the first standard value set in advance, it is judged that there is a problem with the high-pressure system piping, and from the drain system pressure When the second judgment value obtained by subtracting the high-pressure system differential pressure is larger than a preset second standard value, it is judged that the low-pressure system piping is defective.

  According to the above aspect of the present invention, the hydraulic device test method can perform a leak test on both the high-pressure system pipe and the low-pressure system pipe by simply performing a pressurization test on the high-pressure system pipe.

  According to the method for testing a hydraulic device according to the present invention, it is possible to shorten the test time relating to the leak test of the hydraulic device.

1 is a schematic diagram of a hydraulic apparatus according to a first embodiment. 3 is a flowchart showing a flow of a leak test according to the first exemplary embodiment. 6 is a graph for explaining a correlation between a pressure of a high-pressure system pipe and a pressure of a low-pressure system pipe in the test of the hydraulic device according to the first embodiment. It is the schematic of the hydraulic apparatus concerning a comparative example.

Embodiment 1
Embodiments of the present invention will be described below with reference to the drawings. For clarity of explanation, the following description and drawings are omitted and simplified as appropriate. In the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted as necessary.

  The hydraulic device according to the first embodiment (hereinafter referred to as a pressure chamber 1) is, for example, one of components that constitute a brake actuator of an automobile. FIG. 1 shows a schematic diagram of a pressure chamber 1 according to the first embodiment.

  As shown in FIG. 1, the pressure chamber 1 according to the first embodiment includes a high pressure system pipe 11, 12a-12d, a low pressure system pipe 13, a pressure increase valve 21a-21d, a pressure reduction valve 22a-22d, a release valve 23, a pump. 24 is stored in the case. The case is provided with joints J1 to J5 and a drain joint JD. In FIG. 1, valves 41 and 43 and a pressure sensor 42 included in an inspection apparatus for inspecting the pressure chamber 1 are connected to the drain joint JD.

  The valve 41 switches whether to transmit the pressure of the fluid discharged to the pressure sensor 42 via the drain joint JD to the pressure sensor 42. The valve 43 opens when the pressure detected by the pressure sensor 42 becomes a value equal to or higher than a specified pressure, and extracts the fluid pressure into the exhaust box.

  The high-pressure system pipes 11, 12 a to 12 d are pipes that have a high allowable pressure of about several tens of MPa and allow a fluid to flow at a pressure within the allowable pressure. The low pressure system pipe 13 is set to have a lower permissible pressure than the high pressure system pipe. The pressure increasing valves 21a to 21d are valves that pressurize the pressure of the connection destination pipe based on the pressure of the connection source pipe, and include, for example, an electromagnetic valve. The pressure-reducing valves 22a to 22d are valves that reduce the pressure of the fluid in the connection source pipe and give it to the connection destination pipe, and include, for example, an electromagnetic valve. The pump 24 gives the fluid flowing through the low pressure system pipe 13 to the high pressure system pipe 11 while increasing the pressure of the fluid flowing through the low pressure system pipe 13.

  The high pressure system pipe 11 connects the joint J1 and the pressure increasing valves 21a to 21d. The high-pressure system pipe 12a is connected to the high-pressure system pipe 11 via the pressure increasing valve 21a. The high pressure system pipe 12a connects the pressure increasing valve 21a and the joint J2. The pressure increasing valve 21 a pressurizes the pressure of the high pressure system pipe 12 a based on the pressure of the high pressure system pipe 11. The high pressure system pipe 12a is provided with a pressure sensor 31a for detecting the pressure of the high pressure system pipe 12a. For example, a brake caliper on the right front of the vehicle is connected to the joint J2. Further, the low pressure system pipe 13 is connected to the high pressure system pipe 12a through a pressure reducing valve 22a.

  The high-pressure system pipe 12b is connected to the high-pressure system pipe 11 via the pressure increasing valve 21b. The high pressure system pipe 12b connects the pressure increasing valve 21b and the joint J3. The pressure increasing valve 21 b pressurizes the pressure of the high pressure system pipe 12 b based on the pressure of the high pressure system pipe 11. The high pressure system pipe 12b is provided with a pressure sensor 31b for detecting the pressure of the high pressure system pipe 12b. For example, a brake caliper on the left rear of the vehicle is connected to the joint J3. Further, the low-pressure system pipe 13 is connected to the high-pressure system pipe 12b through a pressure reducing valve 22b.

  The high-pressure system pipe 12b is connected to the high-pressure system pipe 11 via the pressure increasing valve 21b. The high pressure system pipe 12b connects the pressure increasing valve 21b and the joint J3. The pressure increasing valve 21 b pressurizes the pressure of the high pressure system pipe 12 b based on the pressure of the high pressure system pipe 11. The high pressure system pipe 12b is provided with a pressure sensor 31b for detecting the pressure of the high pressure system pipe 12b. For example, a brake caliper on the left rear of the vehicle is connected to the joint J3. Further, the low-pressure system pipe 13 is connected to the high-pressure system pipe 12b through a pressure reducing valve 22b.

  The high-pressure system pipe 12c is connected to the high-pressure system pipe 11 via the pressure increasing valve 21c. The high pressure system pipe 12c connects the pressure increasing valve 21c and the joint J4. The pressure increasing valve 21 c pressurizes the pressure of the high pressure system pipe 12 c based on the pressure of the high pressure system pipe 11. The high pressure system pipe 12c is provided with a pressure sensor 31c that detects the pressure of the high pressure system pipe 12b. For example, a brake caliper on the right rear side of the vehicle is connected to the joint J4. Further, the low pressure system pipe 13 is connected to the high pressure system pipe 12c through a pressure reducing valve 22c.

  The high-pressure system pipe 12d is connected to the high-pressure system pipe 11 through the pressure increasing valve 21d. The high pressure system pipe 12d connects the pressure increasing valve 21d and the joint J5. The pressure increasing valve 21 d pressurizes the pressure of the high pressure system pipe 12 d based on the pressure of the high pressure system pipe 11. The high pressure system pipe 12d is provided with a pressure sensor 31d for detecting the pressure of the high pressure system pipe 12d. For example, a brake caliper on the left front of the vehicle is connected to the joint J5. Further, the low pressure system pipe 13 is connected to the high pressure system pipe 12d through a pressure reducing valve 22d.

  The pressure sensor 32 detects the pressure of the high-pressure system pipe 11. The release valve 23 reduces the pressure of the fluid in the high pressure system pipe 11 and discharges it to the low pressure system pipe 13 in response to the pressure in the high pressure system pipe 11 becoming a certain level or higher.

  That is, in the pressure chamber 1 according to the first embodiment, the system constituting the drain system that becomes the flow path of the fluid discharged when the pressure of the high-pressure system pipes 12a to 12d and the high-pressure system pipe 11 is reduced is integrated into one system. It has become a form. The low-pressure system pipe 13 constitutes this drain system. The low-pressure system pipe 13 is connected to a reservoir tank (not shown in FIG. 1) provided outside via a drain joint JD. When the pressure chamber 1 is incorporated in the vehicle body, the pressure chamber 1 according to the first embodiment is configured such that the pump 24 sucks oil from the reservoir tank through the low-pressure system pipe 13 and pressurizes the high-pressure system pipe 11. .

  Then, the test method of the pressure chamber 1 concerning Embodiment 1 is demonstrated. The test for the pressure chamber 1 according to the first embodiment includes a function test for inspecting the open / closed state of various valves and a leak test for inspecting piping and valves in the pressure chamber 1 for leaks. In the functional test, high pressure air corresponding to the allowable pressure of the high pressure system pipe 11 is applied to the pressure chamber 1. And the leak test with respect to the pressure chamber 1 concerning Embodiment 1 can be performed using the measurement result of this functional test. This is because, in the pressure chamber 1 according to the first embodiment, the high pressure side pressure measurement value obtained in the high pressure system pipe in the high pressure leak test for testing the leak in the high pressure system pipe, and the low pressure system pipe in the high pressure leak test. This is for checking leakage of two pipes having different permissible pressures using the obtained low-pressure side pressure measurement value.

  FIG. 2 is a flowchart showing the flow of the leak test of the pressure chamber 1 according to the first embodiment. In addition, the leak test shown in FIG. 2 can also be implemented as one inspection item of the function test.

  As shown in FIG. 2, in the leak test according to the first embodiment, first, all the pressure increasing valves 21a to 21d are closed (step S1). In step S1, the pump 24 is preferably stopped and the pressure increasing valves 21a to 21d are preferably opened. In the leak test according to the first embodiment, the joints J2 to J5 are kept closed.

  Subsequently, in the leak test according to the first embodiment, a measuring instrument is connected to the joint J1, and high-pressure air having a measured pressure is applied to the pressure chamber 1 (step S2). Then, with the high-pressure air applied to the pressure chamber 1, the high-pressure system differential pressure S1 is calculated (step S3) and the drain system pressure S2 is calculated (step S4).

The high-pressure system differential pressure S1 in step S3 is measured by the pressure value PFR measured by the pressure sensor 31a, the pressure value PRL measured by the pressure sensor 31b, the pressure value PRR measured by the pressure sensor 31c, and the pressure sensor 31d. The pressure value PFL and the PACC values measured by the pressure sensor 32 and the value obtained by summing the differences between the measured pressure applied from the measuring device to the pressure chamber 1 are calculated. Specifically, the high-pressure system differential pressure S1 is calculated by the equation (1).
S1 = ΣΔP (PACC, PFR, PRL, PRR, PFL) (1)

The drain system pressure S2 in step S4 is a value obtained by detecting the leak pressure ΔPH obtained from the pressure sensor 42 provided in the drain system constituted by the high-pressure system pipe 11, and multiplying the leak pressure ΔPH by a preset coefficient k. is there. Here, the leak pressure ΔPH indicates the difference between the pressure value obtained from the pressure sensor 42 before the leak test and the pressure value measured by the pressure sensor 42 during the leak test. Specifically, the drain system pressure S2 is calculated by the equation (2).
S2 = ΔPH × k (2)

  Here, the coefficient k will be described in detail. In the pressure chamber 1 according to the first embodiment, even when the pressure increasing valves 21a to 21d are closed, when high pressure air is applied to the high pressure system pipe, a certain leak occurs. Therefore, when a relationship between the pressure of the high-pressure air and the leakage pressure indicating the pressure of the fluid leaking to the low-pressure system pipe 13 is obtained from a plurality of samples, a certain tendency can be understood. FIG. 3 shows a graph for explaining the correlation between the pressure of the high-pressure system pipe and the pressure of the low-pressure system pipe in the test of the hydraulic device according to the first embodiment.

  As shown in FIG. 3, it can be seen that there is a relationship that can be represented by an approximate straight line that is a linear function between the drain system pressure ΔPH of the low-pressure system pipe and the high-pressure system differential pressure S1 of the high-pressure system pipe. Therefore, the slope of this approximate line is used as the coefficient k. When a minute leak occurs in the high-pressure system piping or the low-pressure system piping, the correlation between the high-pressure system differential pressure S1 and the drain system pressure S2 greatly deviates from this approximate straight line. By using this coefficient k, S1 = S2 in an ideal state where no leakage occurs in the two pressure system pipes.

  Subsequently, in the leak test according to the first embodiment, it is determined whether or not the first determination value obtained by subtracting the drain system pressure S2 from the high system differential pressure S1 is smaller than a first standard value set in advance ( Step S5). In this step S5, when the first judgment value is equal to or higher than the first standard value, it is determined that there is an abnormal leak in the high-pressure system piping, and the pressure chamber to be inspected is determined to be defective (step S6). Exit. On the other hand, in the leak test according to the first embodiment, when it is determined in step S5 that the first determination value is smaller than the first standard value, the process of step S7 is performed.

  In step S7, it is determined whether or not the second judgment value obtained by subtracting the high-pressure system differential pressure S1 from the drain system pressure S2 is smaller than a preset second standard value. In this step S7, when the second judgment value is equal to or greater than the second standard value, it is determined that there is an abnormal leak in the low-pressure system piping, and the pressure chamber to be inspected is determined to be defective (step S8). Exit. On the other hand, in the leak test according to the first embodiment, when it is determined in step S7 that the second determination value is smaller than the second standard value, the pressure chamber to be inspected is determined to be non-defective (step S9). End the leak test.

  From the above description, in the leak test method for the pressure chamber 1 according to the first embodiment, the leak test is performed on both the high-pressure system pipe and the low-pressure system pipe only by applying high-pressure air. Thereby, in the leak test of the pressure chamber 1 concerning Embodiment 1, the frequency | count of the air application process with respect to the pressure chamber 1 can be reduced, and test time can be shortened.

  Further, in the leak test method for the pressure chamber 1 according to the first embodiment, the leak test can be performed as one test item of the function test. Thereby, the time for performing a separate leak test can be reduced.

  Further, since the pressure chamber 1 according to the first embodiment has only one drain system, the number of sensors that measure the leakage pressure ΔPH of the drain system can be reduced. Furthermore, by integrating the drain system into one system, the test accuracy can be improved in the leak test of the pressure chamber 1 according to the first embodiment.

  Here, in order to explain the effect of reducing the number of sensors and the effect of improving the test system in the pressure chamber 1 according to the first embodiment and the test thereof, a comparative example is shown, and this effect will be described more specifically. FIG. 4 shows a schematic diagram of the pressure chamber 100 according to the comparative example. The pressure chamber 100 according to the comparative example is a comparative example devised by the inventors.

  As shown in FIG. 4, in the pressure chamber 100 according to the comparative example, the measurement pressure is applied to the high-pressure system pipe 111 via the joint J1 and the linear pressure increasing valve 123. A linear pressure reducing valve 124 is provided between the high pressure system pipe 111 and the low pressure system pipe 113. Further, pressure increase valves 121 a and 121 b, a regulator cut valve 126, and a master cut valve 127 are connected to the high pressure system pipe 111. The pressurized fluid is supplied to the high-pressure system pipe 112a through the pressure increasing valve 121a. A pressurized fluid is supplied to the high-pressure system pipe 112b via the pressure increasing valve 121b. Further, the high pressure system pipe 111 supplies pressurized fluid to the pressure increasing valves 121 c and 121 d through the communication valve 125. The pressurized fluid is supplied to the high-pressure system pipe 112c through the pressure increasing valve 121c. Pressurized fluid is supplied to the high pressure system pipe 112d through a pressure increasing valve 121d.

  Moreover, the pressure of the high-pressure system piping 112a-112d is discharged | emitted by the low-pressure system piping 113 via the pressure-reduction valve 122a-122d, respectively. A pressure sensor 141 and a valve 151 are connected to one end of the low-pressure system pipe 113 via a joint J6. And the drain system comprised by the low voltage | pressure system piping 113 becomes a 1st drain system.

  Further, the regulator cut valve 126 discharges the pressure of the high pressure system pipe 111 to the low pressure system pipe 114. A pressure sensor 142 and a valve 152 are connected to one end of the low-pressure system pipe 114 via a joint J7. And the drain system comprised by the low voltage | pressure system piping 114 becomes a 2nd drain system.

  Further, the master cut valve 127 discharges the pressure of the portion of the high pressure system pipe 111 that has passed through the communication valve 125 to the low pressure system pipe 115. A pressure sensor 143 and a valve 153 are connected to one end of the low-pressure system pipe 115 via a joint J8. Further, the low pressure system pipe 115 is provided with a branch pipe, and the tip of the branch pipe is connected to the low pressure system pipe 116 via the simulator cut valve 128. A pressure sensor 144 and a valve 154 are connected to one end of the low-pressure system pipe 116 via a joint J9. A drain system that discharges pressure through the joint J8 is a third drain system, and a drain system that discharges pressure through the joint J9 is a fourth drain system.

  The pressure chamber 100 according to the comparative example has four drain systems, and each drain system is provided with a pressure sensor. In the case of such a configuration, even if the pressure values provided in the four drain systems are totaled, each pressure value includes an error due to a measurement error of the pressure sensor. Therefore, when the leak pressures of the four pressure values are summed, the measurement errors of the pressure sensors are summed up. For this reason, in the pressure chamber 100 according to the comparative example, there arises a problem that sufficient measurement accuracy cannot be ensured even when the drain system pressure obtained from the pressure sensors 141 to 144 in the high-pressure leak test is used. Further, in order to compensate for the low measurement accuracy of the drain system, it is necessary to separately perform the high-pressure leak test for the high-pressure system pipe and the low-pressure leak test for the low-pressure system pipe.

  However, as described above, in the leak test of the pressure chamber 1 according to the first embodiment, since the drain system is integrated into one system, noise such as measurement error included in the measurement result obtained from the drain system is small. The leak pressure of the drain system can be measured with high accuracy only by performing a high-pressure leak test. Further, by reducing the number of pressure sensors provided in the drain system, simplification of test equipment and cost reduction can be realized.

  In the above description, the invention made by the present inventor has been specifically described based on the embodiments. However, the present invention is not limited to the embodiments already described, and various modifications can be made without departing from the scope of the invention. It goes without saying that changes are possible.

DESCRIPTION OF SYMBOLS 1 Pressure chamber 11, 12a-12d High pressure system piping 13 Low pressure system piping 21a-21d Pressure increase valve 22a-22d Pressure reduction valve 23 Release valve 24 Pump 31a-31d, 32, 42 Pressure sensor 41, 43 Valve J1-J9 Joint 100 Pressure Chamber 111, 112a to 112d High pressure system piping 113 to 116 Low pressure system piping 121a to 121d Pressure increasing valve 122a to 112d Pressure reducing valve 123 Linear pressure increasing valve 124 Linear pressure reducing valve 125 Communication valve 126 Regulator cut valve 127 Master cut valve 128 Simulator cut valve 131a to 131d, 132, 133 Pressure sensor 141 to 144 Pressure sensor 151 to 154 Valve

Claims (1)

A high-pressure system pipe in which a high permissible pressure is set and a low-pressure system pipe in which a permissible pressure is set lower than the high-pressure system pipe, and a drain system constituted by the low-pressure system pipe is integrated into one system A test method for a hydraulic device comprising:
With the pressure reducing valve that connects the high-pressure system pipe and the low-pressure system pipe closed, a measurement pressure for detecting leakage in the high-pressure system pipe is applied to the high-pressure system pipe,
The total value of the difference between the measured pressure and the internal pressure obtained from each of the plurality of pressure sensors provided in the high-pressure system piping is calculated as the high-pressure system differential pressure,
Detecting a leak pressure obtained from a pressure sensor provided in the drain system,
A value obtained by multiplying the leakage pressure by a preset coefficient is calculated as a drain system pressure,
When the first judgment value obtained by subtracting the drain system pressure from the high-pressure system differential pressure is larger than a preset first standard value, it is determined that there is a problem in the high-pressure system piping,
A test method for a hydraulic device that determines that the low-pressure system piping is defective when a second judgment value obtained by subtracting the high-pressure system differential pressure from the drain system pressure is greater than a preset second standard value .

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