JPH1137890A - Pressure leakage inspector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pressure leakage inspector insusceptible to the peripheral apparatus of a facility, for example, that has no trouble due to erroneous measurement in quality judgment. SOLUTION: The opening of a hollow work W is made to abut against a sealing face 2 and the hollow work W is pressed toward the sealing face 2 by an actuator 8 in a clamping jig 3 thus hermetically closing the internal space. On the other hand, the internal space is pressurized to a specified level by an arbitrary means and pressure variation in the internal space is measured by means of an inspection unit 6. In such a pressure leakage inspector, pressurized air supply to the clamping jig 3 is interrupted by an air switching/isolating valve 9 when a pressure leakage is inspected by the inspection unit 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in an apparatus for inspecting pressure leakage of, for example, a crankcase of a motorcycle engine.

[0002]

2. Description of the Related Art Conventionally, when a hollow work such as a crankcase of a motorcycle engine is cast, for example, a pressure leakage inspection device 51 as shown in FIG. Leak testing may be performed.

[0003] This inspection device 51 is mounted with the opening of a hollow work W facing a seal surface 52 made of a urethane rubber plate.
This hollow work W is pressed against the sealing surface 52 by the pressurized air of the upper clamp jig 53 to seal the internal space, and the internal space is pressurized to a predetermined pressure, and the inspection unit 5 is pressed.
At 4, the pressure in the internal space is measured to check for pressure leakage. An actuator 55 is provided on the clamp jig 53, and an air circuit 57 communicating with an air source 56 is connected to the actuator 55. The internal space of the hollow work W is pressurized by a pressure mechanism (not shown) at a predetermined pressure. And a switching valve 58 provided in the air circuit 57.
Thereby, switching of the clamp operation is controlled.

[0004]

However, in the case of the above-described inspection apparatus 51, a pressure change by the clamp jig 53 occurs while the inspection unit 54 performs the pressure leakage inspection.
There may be a problem in inspection.

That is, among the changes in the clamping force, the change in the direction in which the clamping force is weakened is likely to cause pressure leakage and is judged to be in the direction of poor product quality. There is no particular problem for the purpose of the inspection, but when the clamping force changes in the increasing direction, there is a possibility that a poor quality product may be determined as a good product, and there is a problem in the inspection.

For example, in a motorcycle manufacturing process line or the like, when an inspection process is arranged near a cleaning process or the like and the same air source is shared with the cleaning process or the like,
A change in the clamping force is likely to occur due to the influence of peripheral equipment and the like, such as a change in the air pressure due to the use of an adjacent device and the like.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an inspection apparatus which is not affected by, for example, peripheral equipment of a facility and which does not judge a defective product due to an erroneous measurement as a non-defective product.

[0008]

In order to achieve the above object, the present invention provides a clamp jig for pressing a hollow work having an opening abutting on a sealing surface to seal a space in the hollow work, and a sealing jig. A pressurizing mechanism for increasing the pressure of the internal space to a predetermined pressure, an inspection unit for inspecting pressure leakage of the internal space, and a fluid circuit for supplying and driving a pressure fluid of a pressure fluid source to an actuator of the clamp jig. In the pressure leakage inspection device provided, the fluid circuit is provided with a shutoff mechanism that shuts off the flow path while the inspection unit inspects the pressure leakage.

That is, after the hollow work is clamped by operating the actuator, the space in the work is pressurized to a predetermined pressure by any means, the fluid circuit leading to the actuator is cut off, and the leak in the space is inspected. If the clamping force is not affected by the pressure change of the pressure fluid source,
No adverse effect on test results.

Further, when the fluid circuit is cut off, as a general tendency, the clamping force of the actuator gradually changes in a direction in which the clamping force gradually decreases. The direction of the change means that a more severe inspection is performed in the inspection. However, it does not become a problem.

[0011]

Embodiments of the present invention will be described with reference to the accompanying drawings. Here, FIG. 1 is a configuration example diagram of the pressure leakage inspection device according to the present invention.

[0012] The pressure leakage inspection device 1 of the present invention can be used, for example, when casting a hollow workpiece such as a crankcase of a motorcycle.
As shown in FIG. 1, the apparatus is configured as a device for inspecting the presence or absence of a defect such as a casting cavity, and is mounted with a sealing surface 2 made of, for example, a urethane rubber plate and an opening facing the sealing surface 2. Jig 3 for pressing the hollow work W, an air circuit 4 for supplying pressurized air to the clamp jig 3, an air source 5 connected to the air circuit 4, and an internal space of the hollow work W And a test unit 6 for measuring the pressure in the internal space.

The clamp jig 3 includes a pressing plate 7 for pressing the hollow work W and an actuator 8 for moving the pressing plate 7 forward and backward. When the pressing plate 7 moves forward, the hollow work W is pressed and clamped. When the force increases and the pressing plate 7 retreats, the clamping force is reduced.

The air circuit 4 is configured to connect the actuator 8 and the air source 5, and controls switching of the supply path of the pressurized air and interruption of the flow path in the middle of the air circuit 4. An air switching / shutoff valve 9 is provided. That is, the air switching / cutoff valve 9 includes, for example, a clamp position at which the actuator 8 is moved forward to clamp the workpiece W, an unclamped position at which the actuator 8 is moved backward to release the clamping force, and a pressure supplied from the air source 5. It is configured with a three-position switching system for shutting off the compressed air.

A pressurizing mechanism (not shown) for pressurizing a space in the hollow work W can supply, for example, pressurized air adjusted to a predetermined pressure into the space. An air circuit branched from the middle of the air passage 4 or an air circuit provided separately is connected to the internal space.

The pressure leakage inspection apparatus 1 configured as described above
In the inspection, when performing the inspection, the opening of the hollow workpiece W is brought into contact with the sealing surface 2 and positioned, and the air switching / cutoff valve 9
Is set at the clamp position to clamp the work W and simultaneously pressurize the internal space of the work W to a predetermined pressure.

When the operation is completed, the air switching / shutoff valve 9 is switched to the shutoff position to shut off the flow path of the pressurized air supplied from the air source 5 and then the work unit W
Check the pressure in the space. Then, it is checked whether the pressure is within a predetermined range, and it is determined whether the pressure is good.

In such an inspection method, for example, even if the pressure of the air source 5 changes, the clamping force of the clamp jig 3 does not change. Does not adversely affect test results.

When the inspection is completed, the air switching / cutoff valve 9 is switched to the unclamping position, and the hollow work W is discharged.

The present invention is not limited to the above embodiment. Those having substantially the same configuration as those described in the claims of the present invention and exhibiting the same operation and effect belong to the technical scope of the present invention. For example, the clamp pressure of the clamp jig 3 may be a fluid pressure other than air, and the hollow work may be a work other than the crankcase.

[0021]

As described above, in the pressure leakage inspection apparatus according to the present invention, the opening of the hollow work is pressed against the sealing surface by the clamp jig, clamped, and the pressure in the work is measured to measure the pressure leakage. In the inspection device, the flow path between the fluid pressure source and the clamp jig is shut off during the inspection for the pressure leak, so that the clamp jig can be used even if the pressure of the air source changes. The inspection quality can be improved without adversely affecting the force.

[Brief description of the drawings]

FIG. 1 is an explanatory view of a pressure leakage inspection device according to the present invention.

FIG. 2 is an explanatory diagram of a conventional pressure leakage inspection device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Pressure leakage inspection apparatus, 2 ... Seal surface, 3 ... Clamp jig, 4 ... Air circuit, 5 ... Air source, 6 ... Inspection unit, 8
... actuator, 9 ... air switching / shutoff valve, W ... hollow work.

Claims (1)

[Claims] 1. A clamp jig for pressing a hollow work having an opening in contact with a sealing surface to seal an internal space of the hollow work, a pressurizing mechanism for increasing the sealed internal space to a predetermined pressure, and An inspection unit for inspecting pressure leakage of an internal space portion, and a fluid leakage inspection device including a fluid circuit for supplying and driving a pressure fluid of a pressure fluid source to an actuator of the clamp jig, wherein the fluid circuit is And a shut-off mechanism for shutting off the flow path while the check unit is checking for leaks.