JP2941173B2 - Pipeline clogging inspection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for inspecting whether or not a pipe in a work, such as an intake manifold, having a pipe formed in the work is properly formed. About.

[0002]

2. Description of the Related Art An example of an inspection apparatus for a pipe in a work is disclosed in Japanese Patent Application Laid-Open No. 3-105203. In this inspection device, high-pressure air is blown in from one opening of the pipe in the work and discharged from the other opening, while the difference between the pressure in one opening and the pressure in the other opening, that is, Measure the pressure difference. If the conduit in the work is not formed as intended, for example, if the conduit in the work is clogged or the cross-sectional area is reduced, the pressure difference will increase significantly. On the other hand, when the cross-sectional area of the pipe in the work is larger than intended, the pressure difference becomes smaller. In this way, it is possible to inspect whether or not the pipe in the work is properly formed from the pressure difference.

[0003]

However, this pressure difference is easily affected by factors other than the shape of the pipe in the work. For example, as the temperature increases, the pressure difference tends to decrease. Alternatively, the pressure difference tends to increase as the humidity increases. For this reason, due to the influence of the temperature and humidity of the atmosphere, the pressure difference becomes abnormal even if the pipe in the work is normal, or conversely, even if the pipe in the work is not formed properly, The difference becomes normal.
The present invention realizes a technique for preventing occurrence of such erroneous inspection.

[0004]

SUMMARY OF THE INVENTION The present invention is an apparatus for inspecting whether or not a pipeline is properly formed in a work. The apparatus includes an inspection pipeline and one end of the inspection pipeline. A communication jig that communicates with the pipeline in the work in a state of being cut off from the atmosphere, a high-pressure or reduced-pressure generating means provided at the other end of the pipeline for inspection, and a middle of the pipeline for inspection. A first differential pressure sensor provided in the communication jig, for detecting a pressure difference in the pipe in the work; and a reference throttle provided in the inspection pipe, A second differential pressure sensor for detecting a pressure difference between the first and second differential pressure sensors, and a ratio of a pressure difference at the reference throttle by the second differential pressure sensor to the pressure difference at the reference throttle. And a controller for determining whether or not the in-work conduit is properly formed based on It is characterized by comprising. Here, the communication between the inspection pipe and the pipe in the work in a state of being cut off from the atmosphere means that both pipes are connected to each other and both pipes are airtight to the atmosphere. Say.

[0005]

According to this inspection apparatus, the gas under inspection flows at the same flow rate through both the pipeline in the work and the reference throttle. For this reason,
Even if the pressure difference in the pipe inside the work fluctuates due to the temperature and humidity of the gas, the pressure difference in the reference throttle fluctuates accordingly, so the pressure difference in the pipe inside the work and the reference The pressure difference ratio is stable, and correct inspection can be performed against fluctuations in temperature and humidity.

[0006]

Next, an embodiment embodying the present invention will be described. In FIG. 2, a pipe WH is formed in the work W, in this case, the intake manifold W. This conduit W
H may be formed by casting, and it is necessary to check whether it is formed properly. The conduit WH penetrates the work W and has at least two openings WH1 and WH2.

[0007] In the figure, reference numeral 20 denotes an inspection apparatus, which has an inspection pipe line 19. One end of the inspection pipeline 19 is communicated with the in-work pipeline WH by the communication jig 2 in a state of being cut off from the atmosphere. That is, the pipes WH and 19 are communicated with each other, and both the pipe WH and the pipe 19 are hermetically sealed with the atmosphere at the connection portion. That is, the communication jig 2
And the work W are contacted without any gap, and there is no leakage between them.

[0008] In the figure, reference numeral 4 denotes a pipe air-tightly attached to the communication jig 2, which is connected to the communication jig 2 to form a pipe 19, and a differential pressure sensor 12 is attached to a side wall thereof. Have been. The differential pressure sensor 12 has two ports 12a and 12b. One port 12a communicates with a conduit 19 inside the pipe 4, and the other port 12b communicates with the atmosphere. In the figure, reference numeral 6 denotes an on-off valve, which opens and closes the inspection pipeline 19. In the figure, reference numeral 8 denotes a tube in which a reference aperture 8a is formed. A second differential pressure sensor 14 is attached to the pipe 8. The differential pressure sensor 14 has two ports 14a and 14b. One port 14a communicates with one side of the reference throttle 8a, and the other port 14b communicates with the other side of the reference throttle 8a. The pressure difference can be detected. 1 in the figure
Numeral 0 denotes a flow rate adjusting valve for adjusting the flow rate to a constant value, and P denotes a pressure reducing means (in this case, a vacuum pump).

In the case of this apparatus, the communication jig 2 is connected to the work W
By operating the decompression means P by attaching to the opening WH1, the atmosphere is sucked from the opening WH1 of the work W, flows through the pipe WH in the work from the opening WH1 to the side WH2, and further evacuates the inspection pipe 19 from the side of the opening WH2. It flows to the side of the pump P. At this time, a pressure difference is generated between the openings WH1 and WH2 of the work W due to the pressure loss of the pipe WH in the work. The above-described differential pressure sensor 12 detects the pressure (atmospheric pressure) at the opening WH1 and the opening WH2.
To detect the pressure difference at
Detect the pressure difference at. On the other hand, the second differential pressure sensor 14 detects a pressure difference at the reference throttle 8a.

The values detected by the two pressure sensors 12 and 14 are input to a controller 16. The controller 16 receives the signals from the pressure sensors 12 and 14 and performs the processing described below.
During the inspection, the vacuum pump P, the opening / closing valve 6 and the flow rate adjusting valve 10 are controlled so that a constant flow rate flows through the work internal pipeline WH and the inspection pipeline 19 during the inspection.

[0011] The flow rate is constant and the pipe WH
Even if the shape is constant, the pressure difference in the pipe in the work is not constant due to the temperature and humidity of the atmosphere. For example, when the temperature is high, the pressure difference is small, and when the humidity is high, the pressure difference is likely to be large. For this reason, if the pressure difference itself is used as an index for inspection, the inspection result becomes abnormal even if the shape of the pipe WH in the work is normal due to the influence of temperature and humidity, or the shape of the pipe WH in the work is abnormal. However, the test index may be normal.

However, in this apparatus, a flow rate equal to the flow rate in the work internal line WH is caused to flow through the reference throttle 8a.
The pressure difference at the reference throttle 8a is also obtained, and the ratio of the pressure difference at the work internal pipeline WH to the pressure difference at the reference throttle 8a is used as an inspection index. By calculating this ratio, the influence of the temperature fluctuation and humidity fluctuation of the atmosphere is canceled out, and the inspection result corresponds well to the flow resistance of the pipe in the work.

As shown in FIG. 3, the controller 16
The pressure difference (PX) at the pipe in the work is divided by the pressure difference (PM) at the reference throttle, and the divided value is compared with the upper limit value (UL) and the lower limit value (LL). Upper limit (UL) and lower limit (L
L), the work W is accepted, and if not, the work W is rejected. In this way, the influence of the measurement conditions is canceled, and an inspection result that corresponds well to the shape of the pipe in the work can be obtained.

In this embodiment, the reference stop 8a may be a work W in which the pipe WH in the work is accurately formed, that is, a measurement master. In this case, the inspection result moves up and down around 1.0, and the inspection accuracy is improved. Further, in this embodiment, the pressure reducing means P may be replaced with a high pressure means. However, when the pressure reducing means is used, the differential pressure sensor 1 having better detection sensitivity is used.
2, 14 can be used, and from the viewpoint of inspection accuracy, it is better to use the decompression means. Also, in order to keep the flow rate constant, the use of the decompression means can simplify the apparatus configuration.
Further, it is easier to maintain the airtightness of the communication jig 2 by performing the inspection under reduced pressure.

This embodiment enables the inspection of the intake manifold shown in FIG. This intake manifold W has one opening WH1 and six branch pipes W1 to W
6 and can be inspected for each branch pipe. For this purpose, communication jigs 21 and 21 are connected to the branch pipes W1 to W6.
2, 23, 24, 25, and 26 are attached, and the differential pressure sensors 121, 122, 123, 124, 125, and 126 respectively detect the inlet WH1 and the outlet (the communication jigs 21 to 26 and the branch pipe) for each branch pipe. (Connection point of W1 to W6)
The pressure difference between them can be detected.

However, this inspection apparatus does not inspect six branch pipes at once, but inspects each one. For this purpose, on-off valves 61, 62, 63, 64, 65, 6 are provided downstream of the pipes 41, 42, 43, 44, 45, 46, respectively.
6 is provided, and the controller 16 controls the open / close valves 61, 62,
63, 64, 65 and 66 are controlled. Controller 16
When the inspection of one branch pipe is completed, the on-off valve for the adjacent branch pipe is opened and the on-off valve for the tested branch pipe is closed.

In FIG. 1, reference numeral 70 denotes an assembly member of the inspection pipes, and reference numerals 71 to 76 denote inspection pipes branched corresponding to the respective branch pipes 41 to 46. In the case of this embodiment, each of the branch pipes W1 to W6 and the communication jigs 21 to 26 are connected by a single operation. A tube 8 having a restriction 8a formed therein is connected to the end of the collecting member 70 as in FIG. 2, and a differential pressure sensor 14 is attached to the tube 8. Tube 8
Is connected to a pressure reducing means P. Thus 6
Even in a device for inspecting a branch pipe, only one pipe 8, the differential pressure sensor 14, and the pressure reducing means P may be used. In the case of this embodiment, the inspection preparation processing for the six branch pipes is executed at a time. This simplifies the preparation process. On the other hand, the actual inspection is performed independently one by one, and each branch pipe is inspected accurately one by one. In the case of the above-described embodiment, only one communication jig corresponding to one pipe in the work is required to connect the test pipe and the high pressure or pressure reducing means to one side of the work. On the other hand, two communication jigs may be used for one pipe in the work, the test pipe may be attached to one side of the work, and high pressure or pressure reducing means may be connected to the other side.

[0018]

According to the present invention, in a state where the same flow rate flows through the pipe in the work and the reference throttle, the pressure difference in the pipe in the work and the pressure difference in the reference throttle are detected, and the ratio of the two pressure differences is determined. Since the inspection index is used as the inspection index, it is possible to perform an inspection using an index in which changes in temperature and humidity are offset, thereby preventing erroneous inspection.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an apparatus according to an embodiment.

FIG. 2 is a schematic view of an apparatus according to one embodiment.

FIG. 3 shows an example of a measurement index.

[Explanation of symbols]

 2 Communication jig 8a Reference aperture 12, 14 Differential pressure sensor 19 Inspection pipeline P High pressure / pressure reduction means W Work WH Work internal pipeline

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Kazuya Sakai 1-1-1 Asahi-cho, Kariya-shi, Aichi Prefecture Inside Toyota Koki Co., Ltd. (72) Inventor Hironori Watanabe 1-Toyota-cho, Toyota-shi, Aichi Prefecture Toyota Motor Co., Ltd. (72) Inventor: Isao Ogata 1 Toyota Town, Toyota City, Aichi Prefecture Inspector, Toyota Motor Corporation Takuya Okada (56) References JP-A-3-105203 (JP, A) JP-A-2-263109 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) G01B 13/00-13/24 G01M 3/00

Claims (1)

(57) [Claims] 1. A device for inspecting whether or not a pipeline is properly formed in a work, comprising: a pipeline for inspection; and one end of the pipeline for inspection with respect to the pipeline in the work. A communication jig communicating with the air in a state of being cut off from the atmosphere, a high-pressure or reduced-pressure generating means provided at the other end of the inspection pipe, and a reference throttle provided in the middle of the inspection pipe, A first differential pressure sensor provided on the communication jig and detecting a pressure difference in the pipe in the work; a second differential pressure sensor provided on the inspection pipe and detecting a pressure difference in the reference throttle; And a second differential pressure sensor, based on a ratio of a pressure difference between the first differential pressure sensor in the work internal pipe and the second differential pressure sensor at the reference throttle. And a controller for judging whether or not is properly formed. Road-clogging inspection apparatus.