JP5740927B2 - Fluid pressure inspection method and fluid pressure inspection device - Google Patents

Description

  The present invention relates to a fluid pressure inspection method and a fluid pressure inspection device, and more particularly to a technique for inspecting an internal pressure in a fluid pressure system.

  2. Description of the Related Art Conventionally, a fluid pressure system such as a hermetic hydraulic system including an actuator is known, such as a KDSS (Kinetic Dynamic Suspension System: a system that controls the front and rear suspension stabilizers to ensure steering stability of a vehicle body). In such a fluid pressure system, a technique for inspecting the fluid pressure inside (in the case of a hydraulic system) is required in order to check whether or not the fluid is properly injected into the inside. . As a technique for inspecting the fluid pressure in the fluid pressure system, a technique is known in which a pressure sensor is provided in a part of the fluid pressure system and the pressure of the internal fluid is measured (see, for example, Patent Document 1).

  In the fluid pressure system, a piston type accumulator may be provided in a part of the actuator, and the fluid pressure in the fluid pressure system can be inspected by detecting the position of the piston. In order to inspect the internal state of such an accumulator, a technique for detecting the position of a piston by providing a displacement detector in the accumulator is known (for example, see Patent Document 2).

  On the other hand, a technique is also known in which an ultrasonic sensor is brought into contact with the container from the outside to check the presence or absence of fluid inside the container (see, for example, Patent Document 3).

JP 2007-192297 A JP 7-269503 A JP 2009-300374 A

  When the technology for providing a pressure sensor in a part of the fluid pressure system described in Patent Document 1 is applied to a hydraulic system in an automobile such as the KDSS, for example, the pressure sensor is installed in the fluid pressure system for each vehicle. There is a need. Specifically, as shown in FIG. 6, a pressure sensor is disposed in a valve unit incorporated in the hydraulic system. Then, the hydraulic pressure inside the valve unit is detected by the pressure sensor and displayed by the display means. However, after the vehicle is shipped, the pressure sensor is not used, and disposing the pressure sensor for each vehicle only for the inspection of the hydraulic system before the shipment increases the cost of parts.

  Similarly, in the technique described in Patent Document 2, it is necessary to incorporate a displacement detector in an accumulator by being incorporated in a fluid pressure system for each vehicle, which causes a cost increase due to the cost of parts for each vehicle.

  On the other hand, Patent Document 3 discloses a specific method for inspecting the fluid pressure inside the container, such as an accumulator, even though the presence or absence of the fluid inside the container can be confirmed by the described technique. It wasn't.

  In view of the above, the present invention makes it unnecessary to provide an inspection means for each fluid pressure system by inspecting the fluid pressure inside the fluid pressure system from the outside, and can reduce the component cost. A fluid pressure inspection method and a fluid pressure inspection device are provided.

  The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described.

In other words, in the first aspect, the fluid pressure inspection method inspects the fluid pressure of the fluid pressure system provided with the accumulator by inspecting the fluid pressure inside the accumulator with a plurality of ultrasonic sensors. The accumulator includes a cylinder, a piston accommodated in the cylinder, and a positioning member in which a depression is formed, and a gas in which the piston is filled in the cylinder by a fluid pressure in the fluid pressure system. The ultrasonic sensor is arranged in a jig through an elastic body, and the jig is used to keep a relative position with the accumulator constant. As a positioning member, it is provided with a rod-shaped positioning pin and stopper protruding upward and formed protruding downward The upper end surfaces of the plurality of ultrasonic sensors are positioned above the upper end of the stopper when not inspected, and the upper end portions of the positioning pins are recessed in the positioning member of the accumulator. Inserting and bringing the upper end of the stopper into contact with the cylinder compressed the elastic body supporting the plurality of ultrasonic sensors to determine the distance from the outer peripheral surface of the cylinder in the accumulator. In the state, the plurality of ultrasonic sensors arranged side by side in the sliding direction of the piston are brought into contact with the outer peripheral surface of the cylinder, and the difference in response waveforms detected by the plurality of ultrasonic sensors The fluid pressure of the fluid pressure system is inspected by detecting the position of the piston .

According to a second aspect of the present invention, there is provided a fluid pressure testing apparatus that includes a plurality of ultrasonic sensors that test a fluid pressure inside the accumulator, and that tests a fluid pressure of a fluid pressure system including the accumulator. A cylinder, a piston accommodated in the cylinder, and a positioning member having a recess formed therein, and the piston compresses the gas filled in the cylinder by the fluid pressure in the fluid pressure system. The ultrasonic sensor is arranged in a jig through an elastic body, and the jig is a rod-like member as a positioning member for keeping a relative position with the accumulator constant. A positioning pin and a stopper are provided to protrude upward, and a gripping portion formed to protrude downward is provided. The upper end surfaces of several ultrasonic sensors are positioned above the upper end of the stopper in a state where no inspection is performed, and the upper end portion of the positioning pin is inserted into the depression of the positioning member of the accumulator. In a state where the elastic body supporting the plurality of ultrasonic sensors is compressed by bringing the upper end of the accumulator into contact with the cylinder, and the distance from the outer peripheral surface of the cylinder in the accumulator is determined. The plurality of ultrasonic sensors arranged side by side in the sliding direction are brought into contact with the outer peripheral surface of the cylinder, and the position of the piston is detected from the difference in response waveforms detected by the plurality of ultrasonic sensors. By doing so, the fluid pressure of the fluid pressure system is inspected .

  As effects of the present invention, the following effects can be obtained.

  According to the present invention, by inspecting the fluid pressure inside the fluid pressure system from the outside, it is not necessary to provide an inspection means for each fluid pressure system, and the component cost can be reduced.

The schematic side view which showed the hydraulic system which is a test object of a fluid pressure test | inspection apparatus. (A), (b) is the side view which showed the state which is performing the fluid-pressure test method which concerns on 1st embodiment, respectively. (A) is a diagram showing the response waveform in FIG. 2 (a), (b) is a diagram showing the response waveform in FIG. 2 (b), (c) shows the relationship between the oil injection pressure and the piston position. Figure. (A), (b) is the side view which showed the state which is performing the fluid pressure test method which concerns on 2nd embodiment and 3rd embodiment, respectively. (A), (b) is the side view and front view which respectively showed the fluid-pressure test apparatus by another Example, (c) showed the state currently test | inspected using the fluid-pressure test apparatus by another Example. Side view. The schematic side view which showed the hydraulic system which concerns on a prior art.

Next, embodiments of the invention will be described.
It should be noted that the technical scope of the present invention is not limited to the following examples, but broadly covers the entire scope of the technical idea that the present invention truly intends, as will be apparent from the matters described in the present specification and drawings. It extends.

[Fluid pressure system]
First, an outline of a fluid pressure system to be subjected to a fluid pressure test will be described with reference to FIGS. 1 and 2. The fluid pressure system shown in FIG. 1 is a KDSS in an automobile and is a sealed hydraulic system including an actuator.

  That is, the fluid pressure system includes an actuator including a valve unit and an accumulator, and a front cylinder and a rear cylinder disposed in each of the front stabilizer and the rear stabilizer. Each component is connected by hydraulic piping and filled with oil.

Further, as shown in FIG. 2, the accumulator is a so-called piston type accumulator, and includes a cylinder and a piston accommodated in the cylinder. Further, the cylinder is filled with a high pressure gas and a pressure adjusting liquid. When the hydraulic pressure in the fluid pressure system increases, as shown in FIG. 2A, the piston is configured to contract the metal bellows while compressing the high-pressure gas filled in the cylinder and slide in the cylinder. -ing That is, when the hydraulic pressure in the fluid pressure system is lowered, the piston is pushed back by the internal pressure of the high-pressure gas as shown in FIG. 2B and is located at the end of the accumulator on the valve unit side.
In this specification, KDSS in an automobile is used as a fluid pressure system to be subjected to a fluid pressure test. However, if a piston type accumulator is used as an actuator of the fluid pressure system, the following fluid pressure test is applied. The target configuration is not limited.

[First embodiment]
Next, the fluid pressure test method according to the first embodiment will be described with reference to FIGS. 2 (a) and 2 (b) and FIGS. 3 (a) and 3 (b).
The fluid pressure testing method according to the present embodiment detects the piston position of a fluid pressure system equipped with an accumulator by testing the fluid pressure inside the accumulator with an ultrasonic sensor 11 provided in the fluid pressure testing device 10. It is. Specifically, as shown in FIGS. 2A and 2B, the ultrasonic sensor 11 is brought into contact with the outer peripheral surface of the cylinder in the accumulator, and the detected response waveform is displayed on a monitor or the like connected to the ultrasonic sensor 11. It is displayed on the display means 12. The ultrasonic sensor 11 is disposed at the oil inflow side end (valve unit side end) in the sliding direction of the piston on the cylinder outer peripheral surface.

  At this time, when oil is present in the portion of the cylinder where the ultrasonic sensor 11 is in contact, the ultrasonic wave emitted from the ultrasonic sensor 11 is directly transmitted as shown in FIG. Sound propagates through the oil and strikes and reflects off the opposite wall of the cylinder. Further, as shown in FIG. 2A, the reflected sound propagates through the oil and returns to the ultrasonic sensor 11. In other words, in this case, the ultrasonic response waveform detected by the ultrasonic sensor 11 and displayed by the display means 12 includes the passage of the round-trip time of the ultrasonic in the cylinder as shown in FIG. The amplitude (reflection) due to the reflected sound appears later.

  On the other hand, when no oil is present in the portion of the cylinder where the ultrasonic sensor 11 is in contact as shown in FIG. 2B, in other words, the piston is applied to the portion where the ultrasonic sensor 11 is in contact. When high pressure gas or the like is present, the ultrasonic wave emitted from the ultrasonic sensor 11 does not propagate through the cylinder because there is no oil as a propagation material. That is, in this case, since the ultrasonic response waveform detected by the ultrasonic sensor 11 and displayed on the display means 12 does not show the amplitude (echo) due to the reflected sound as shown in FIG. is there.

  Here, when the hydraulic pressure in the fluid pressure system is higher than a predetermined value, the piston is pushed to the opposite side of the valve unit by oil as shown in FIG. On the other hand, when the hydraulic pressure in the fluid pressure system is lower than a predetermined value, the piston is pushed back by the high-pressure gas as shown in FIG. 2 (b) and is located at the end of the accumulator on the valve unit side.

  That is, the presence or absence of a piston at the end of the accumulator on the valve unit side can be detected by bringing the ultrasonic sensor 11 into contact with the end of the accumulator on the valve unit side of the outer peripheral surface of the cylinder. In other words, if the hydraulic pressure in the fluid pressure system is higher than a predetermined value, the piston does not exist at the end of the accumulator on the valve unit side and is pushed to the opposite side of the valve unit. Thus, it is possible to determine whether or not the hydraulic pressure in the fluid pressure system is higher than a predetermined value.

  Specifically, when the high-pressure gas in the accumulator is sealed at 2 MPa, for example, the fluid pressure inspection method according to this embodiment is performed, and the response waveform of the ultrasonic wave is reflected by reflected sound as shown in FIG. When amplitude (echo) appears, it can be seen that the piston is not positioned at the end of the accumulator on the valve unit side because the piston is pushed to the opposite side of the valve unit by hydraulic pressure. That is, it can be confirmed that the hydraulic pressure in the fluid pressure system is larger than 2 MPa which is the internal pressure of the high-pressure gas.

  On the other hand, in the above case, the fluid pressure inspection method according to the present embodiment is performed, and when the amplitude (echo) due to the reflected sound does not appear in the ultrasonic response waveform as shown in FIG. It can be seen that it is pushed back by the gas and is located at the end of the accumulator on the valve unit side. That is, it can be confirmed that the hydraulic pressure in the fluid pressure system is smaller than 2 MPa which is the internal pressure of the high-pressure gas.

  As described above, the fluid pressure inspection method according to the present embodiment is configured to detect the piston position of the fluid pressure system provided with the accumulator by inspecting the fluid pressure inside the accumulator with the ultrasonic sensor 11. It is doing.

[Second Embodiment]
Next, the fluid pressure inspection method according to the second embodiment will be described with reference to FIGS. 3 (a) to 3 (c) and FIG. 4 (a).
In the fluid pressure inspection method according to the present embodiment, the ultrasonic sensor 11 provided in the fluid pressure inspection apparatus 10 according to the first embodiment is in contact with the outer peripheral surface of the cylinder, and the arrow A in FIG. As shown, the fluid pressure of the fluid pressure system provided with the accumulator is inspected by moving the piston in the sliding direction and inspecting the fluid pressure inside the accumulator.

At this time, in the portion of the cylinder where oil is present as in the range R1 in FIG. 4A, the response of the ultrasonic wave detected by the ultrasonic sensor 11 as in the first embodiment. In the waveform, as shown in FIG. 3A, the amplitude (echo) due to the reflected sound appears after the lapse of the round-trip time in the cylinder of the ultrasonic wave.
On the other hand, in the portion of the cylinder where oil is not present as in the range R2 in FIG. 4A, the response waveform of the ultrasonic wave detected by the ultrasonic sensor 11 is shown in FIG. As shown, the amplitude (reflection) due to the reflected sound does not appear.

  Therefore, when the response waveform in which the amplitude (echo) due to the reflected sound appears as shown in FIG. 3A changes to a response waveform where the amplitude (echo) due to the reflected sound does not appear as shown in FIG. It can be seen that the piston is located at the position of the ultrasonic sensor 11 when the response waveform changes. That is, the response waveforms detected by the response waveform ultrasonic sensor 11 are compared, and the position of the piston can be detected from the difference.

  Here, as shown in FIG. 3C, the oil injection pressure (MPa) in the accumulator (fluid pressure system) and the piston position in the cylinder (distance from the end of the accumulator on the valve unit side, FIG. (The length of the range R1) (mm) shown in FIG. That is, the oil injection pressure in the accumulator (fluid pressure system) and the piston position in the cylinder have a relationship in which when one is determined, the other is uniquely determined.

  As a result, when the piston position in the accumulator (the length of the range R1 shown in FIG. 4A) is found as described above, the oil injection pressure in the accumulator (fluid pressure system) can be found from FIG. 3C accordingly. It is. That is, it is possible to detect the magnitude of the hydraulic pressure in the fluid pressure system.

[Third embodiment]
Next, the fluid pressure test method according to the third embodiment will be described with reference to FIGS. 3 (a) to 3 (c) and FIG. 4 (b).
As shown in FIG. 4B, the fluid pressure testing method according to the present embodiment includes a plurality of ultrasonic sensors 11, 11,... Provided in the fluid pressure testing device 10 arranged side by side in the piston sliding direction. The fluid pressure of the fluid pressure system is inspected by detecting the position of the piston in contact with the outer peripheral surface of the cylinder and detecting the position of the piston from the difference in the response waveforms detected by the plurality of ultrasonic sensors 11. Is. In FIG. 4B, only one display means 12 connected to each ultrasonic sensor 11 is shown, and the other display means 12, 12... Are not shown.

  Also in the present embodiment, the response waveforms displayed on the respective display means differ depending on the presence or absence of oil. That is, the amplitude (echo) due to the reflected sound appears next to the ultrasonic sensor 11 that detects the response waveform in which the amplitude (echo) due to the reflected sound appears as shown in FIG. When there is an ultrasonic sensor 11 that has detected no response waveform, it can be seen that the piston is located at the position of the ultrasonic sensor 11 that has detected a response waveform in which the amplitude (echo) due to the reflected sound does not appear. That is, the response waveforms detected by the response waveform ultrasonic sensors 11, 11,... Can be compared, and the position of the piston can be detected from the difference. Since the oil injection pressure in the accumulator (fluid pressure system) is known as in the second embodiment, the hydraulic pressure in the fluid pressure system can be detected.

As described above, according to the fluid pressure inspection method according to the first to third embodiments, the inspection means is provided for each fluid pressure system by detecting the piston position inside the fluid pressure system from the outside. Can be eliminated, and the component cost can be reduced.
Specifically, when the fluid pressure inspection method is applied to, for example, a hydraulic system in an automobile, it is not necessary to incorporate pressure detection means such as a pressure sensor in the fluid pressure system for each vehicle, so that the component cost can be reduced. It can be done.

[Another embodiment]
Next, a fluid pressure inspection apparatus 110 according to another embodiment will be described with reference to FIGS.
In the fluid pressure inspection apparatus 110 according to the present embodiment, the ultrasonic sensors 11, 11... Used in the fluid inspection method according to the third embodiment are disposed on a jig 15 that is a plate-like member. Yes. Specifically, as shown in FIGS. 5A and 5B, the plurality of ultrasonic sensors 11, 11... Are fixed in parallel to a fixed portion 13 formed in a rectangular parallelepiped shape. It is disposed on the upper surface of the jig 15 via a spring 14 which is an elastic body. The jig 15 is provided with rod-like positioning pins 17 and 17 and a stopper 18 protruding upward, which are positioning members for keeping the relative position between the fluid pressure testing device 110 and the accumulator constant. In addition, the jig 15 includes a grip 16 formed on the lower surface thereof so as to protrude downward. In FIG. 5, the display means connected to each of the ultrasonic sensors 11, 11,.

  In the accumulator to be inspected by the fluid pressure inspection apparatus 110 according to the present embodiment, the upper end portions of the positioning pins 17 and 17 are positioned when inspecting using the fluid pressure inspection apparatus 110 as shown in FIG. A positioning member having a depression formed below is disposed at a place to be performed. And when inspecting using the fluid pressure test apparatus 110, as shown in FIG.5 (c), by inserting the upper end part of the positioning pins 17 and 17 into the hollow of the positioning member of an accumulator, a fluid pressure test apparatus 110 is positioned relative to the accumulator.

  The upper end surfaces of the plurality of ultrasonic sensors 11, 11,... In the fluid pressure inspection apparatus 110 are positioned above the upper end of the stopper 18 as shown in FIG. It is configured. When the fluid pressure inspection device 110 performs the inspection, as shown in FIG. 5 (c), the plurality of ultrasonic sensors 11, 11,... The springs 14 supporting the sensors 11, 11... Are compressed. At this time, the upper end of the stopper 18 is brought into contact with the cylinder, and the distance from the cylinder outer peripheral surface of the accumulator of the fluid pressure inspection device 110 (the jig 15) is determined, so that the inspection can be performed once or multiple times. The pressing force of the ultrasonic sensors 11, 11,...

The specific content of the fluid pressure testing method by the fluid pressure testing device 110 according to the present embodiment is substantially the same as the fluid pressure testing method according to the third embodiment. That is, as shown in FIG. 5C, the fluid pressure testing device 110 is positioned while being positioned by the positioning pins 17 and 17 and the stopper 18 so that the ultrasonic sensors 11, 11,... Are aligned in the sliding direction of the piston. Then, by bringing the fluid pressure testing device 110 close to the accumulator, the plurality of ultrasonic sensors 11, 11,... Are brought into contact with the outer peripheral surface of the cylinder. Then, the fluid pressure of the fluid pressure system is inspected by detecting the position of the piston from the difference in the response waveforms detected by the plurality of ultrasonic sensors 11.
As described above, the fluid pressure testing apparatus 110 according to the present embodiment also eliminates the need to provide a testing unit for each fluid pressure system by testing the fluid pressure inside the fluid pressure system from the outside. Can be reduced.

10 Fluid pressure inspection device 11 Ultrasonic sensor

Claims (2)

A fluid pressure inspection method for inspecting the fluid pressure of a fluid pressure system provided with the accumulator by inspecting the fluid pressure inside the accumulator with a plurality of ultrasonic sensors,
The accumulator includes a cylinder, a piston accommodated in the cylinder, and a positioning member in which a depression is formed, and gas filled in the cylinder by the fluid pressure in the fluid pressure system. Configured to slide in the cylinder while compressing,
The ultrasonic sensor is disposed on a jig via an elastic body,
The jig is provided with a rod-shaped positioning pin and a stopper protruding upward as a positioning member for keeping the relative position with the accumulator constant, and a gripping portion formed protruding downward,
The upper end surfaces of the plurality of ultrasonic sensors are located above the upper end of the stopper in a state where inspection is not performed,
The elastic body supporting the plurality of ultrasonic sensors is compressed by inserting the upper end portion of the positioning pin into the recess of the positioning member of the accumulator and bringing the upper end of the stopper into contact with the cylinder. The plurality of ultrasonic sensors arranged side by side in the sliding direction of the piston in a state in which the distance from the outer peripheral surface of the cylinder in the accumulator is determined, abuts the outer peripheral surface of the cylinder, and Inspecting the fluid pressure of the fluid pressure system by detecting the position of the piston from the difference in the response waveforms detected by the ultrasonic sensor of
A fluid pressure inspection method characterized by the above. A fluid pressure testing apparatus comprising a plurality of ultrasonic sensors for testing fluid pressure inside an accumulator, and testing fluid pressure of a fluid pressure system provided with the accumulator,
The accumulator includes a cylinder, a piston accommodated in the cylinder, and a positioning member in which a depression is formed, and gas filled in the cylinder by the fluid pressure in the fluid pressure system. Configured to slide in the cylinder while compressing,
The ultrasonic sensor is disposed on a jig via an elastic body,
The jig is provided with a rod-shaped positioning pin and a stopper protruding upward as a positioning member for keeping the relative position with the accumulator constant, and a gripping portion formed protruding downward,
The upper end surfaces of the plurality of ultrasonic sensors are located above the upper end of the stopper in a state where inspection is not performed,
The elastic body supporting the plurality of ultrasonic sensors is compressed by inserting the upper end portion of the positioning pin into the recess of the positioning member of the accumulator and bringing the upper end of the stopper into contact with the cylinder. The plurality of ultrasonic sensors arranged side by side in the sliding direction of the piston in a state in which the distance from the outer peripheral surface of the cylinder in the accumulator is determined, abuts the outer peripheral surface of the cylinder, and Inspecting the fluid pressure of the fluid pressure system by detecting the position of the piston from the difference in the response waveforms detected by the ultrasonic sensor of
A fluid pressure inspection apparatus characterized by the above.

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