JP3143817B2 - Inspection device for flow path in molded product - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention inspects whether or not a flow path is properly secured or formed in a molded article, such as a cylinder block of an engine, which is formed to have a flow path secured therein. To a device that Here, the molded article refers to an article in which a wall material and a flow path are molded in the same step, such as a casting or a resin molded article.

[0002]

2. Description of the Related Art Japanese Unexamined Utility Model Publication No. 63-7344 discloses a method for inspecting whether or not a flow passage is properly formed in a cylinder block cast to secure a cooling water passage therein. Inspection devices have been proposed. In this apparatus, a compressed air supply source is connected to one outlet of a flow path, and all other outlets are hermetically sealed with caps. Then, one of the caps is removed, a pressure gauge is attached, and compressed air is supplied from the compressed air supply source into the flow path. An outlet connected to the compressed air supply and a pressure gauge are attached depending on whether the pressure detected by the pressure gauge is close to the pressure that would occur when the flow path is properly formed. Check that the flow path is properly formed between the outlets. Note that the outlet here is a general term for a portion where the flow path is opened outside the molded product, and the inlet and the outlet are not distinguished.

[0003]

When the entire flow path is inspected by this apparatus, a compressed air supply source and a pressure gauge are attached to each of the outlets on the most upstream side and the most downstream side. If the pressure detected in this state is an appropriate value, the entire flow path should be properly formed. However, the inventor of the present invention has conducted various experiments, and has found that the abnormality is often overlooked in the above-described inspection apparatus even if there is an abnormality in the middle portion of the flow path. This may be because a slight abnormality in the middle part may not significantly affect the overall pressure. In the present invention,
Can test the implementation of each part of the channel, it is to propose a testing apparatus which does not overlooked even partial abnormality.

[0004]

For this purpose, the present invention has created an apparatus for inspecting a flow path in a molded article having the following structure. That is, the inspection apparatus according to the present invention is an apparatus for inspecting whether or not the flow path is properly formed in a molded article formed so that a flow path having a plurality of outlets communicating with the outside is secured inside. , and the pressure generating device is attached to one outlet of the flow path, the pressure generating device is attached to a plurality of outlets, excluding at least another one outlet is opened to the outlet and the atmosphere that is attached, the flow path Means for detecting a pressure difference in the inner stroke, and comparing the pressure difference detected in a state where the atmosphere is flowing through the outlet opened to the atmosphere by operating the pressure generating device with a reference value. Means for judging suitability. Note that the pressure generating device here refers to a vacuum pump that generates a pressure lower than the atmospheric pressure, a compression pump that generates a pressure higher than the atmospheric pressure, or the like. The means for detecting the pressure difference may be a means for directly detecting the pressure difference, or a means for detecting the pressure and detecting the pressure difference from the difference between the detected values.

[0005]

According to the inspection apparatus having this configuration, a pressure difference is applied between one outlet to which the pressure generating device is attached and the other outlet which is not hermetically sealed and opened to the atmosphere. Then, in this state, the pressure difference in the stroke in the flow path is detected. Then , since the pressure difference detected in the stroke is compared with a reference value, it is checked whether or not the flow path in the stroke is properly formed. The inspection apparatus, in order to test for each stroke of the flow <br/> path, can also be accurately inspect the partial abnormality that would be overlooked in the entire test.

[0006]

Next, embodiments of the present invention will be described. Figure 1 shows the first
1 shows an embodiment and is developed for inspecting whether or not a flow path 4 is properly formed in a cylinder block 2 of an engine. Although the flow path 4 is shown only schematically in the drawing, it is actually very complicated. This cylinder block 2 is for five cylinders, and five sets of the same flow path pattern are formed.
The flow path 4 communicates with the outside of the cylinder block 2 at a total of 12 points as shown in 2a to 2l (ell). That is, it has twelve outlets.

One of these outlets, in this case outlet 21
At (L), a vacuum pump 12 is attached via a valve 8 and a flow control valve 10. 14g connecting pipe at 2g outlet
However, a connecting pipe 14h is attached to the outlet 2h, a connecting pipe 14i is attached to the outlet 2i, a connecting pipe 14j is attached to the outlet 2j, and a connecting pipe 14k is attached to the outlet 2k. A pressure difference sensor P1 for detecting a pressure difference is attached between the connection pipes 14g and 14h. A pressure difference sensor P2 for detecting a pressure difference is attached between the connection pipes 14h and 14i. Connecting pipes 14i and 1
A pressure difference sensor P3 for detecting a pressure difference is attached between the terminals 4j. A pressure difference sensor P4 for detecting a pressure difference is attached between the connection pipes 14j and 14k. Therefore, the pressure difference sensor P1 detects the pressure difference in the stroke I of the flow path 4, the pressure difference sensor P2 detects the pressure difference of the stroke II in the flow path 4, and the pressure difference sensor P3 detects the pressure difference in the flow path 4. Trip III of
, And the pressure difference sensor P4 detects the pressure difference of the stroke IV in the flow path 4. The remaining outlets 2a to 2f
Except for one outlet 2f, each is hermetically sealed by caps 6a to 6e.

At the time of inspection, the vacuum pump 12 is operated while the flow rate is kept constant by the flow control valve 10. Then, the atmosphere is sucked from the outlet 2f and flows out of the outlet 21 (e), and in this state, an equilibrium state is established. In this state, the pressure differences P1, P2,
P3 and P4 are detected. Detected pressure difference P1, P
2, P3 and P4 are input to the controller 16.

The controller 16 is constituted by a computer, and first obtains the sum of the pressure differences P1, P2, P3, P4. Then, the pressure difference is normalized by dividing the detected pressure difference by the sum. Hereinafter, the standardized pressure differences are referred to as Pa1, Pa2, Pa3, and Pa4. This normalized pressure difference is a relative pressure difference. Therefore, even if the pump capacity changes or the flow rate changes due to a change in temperature or the like, the value is converted to a value from which the influence of the change has been removed.

As described above, the cylinder head 2 has five flow path patterns. For this reason, if the flow path is properly formed, the pressure differences in each of the strokes I to IV should be substantially equal. Therefore, the standardized pressure difference Pai (i = 1 to 4) should be 0.25 (25%). A display 18 is connected to the controller 16, and the display 18 displays a standardized pressure difference as illustrated in (a) to (e).

(A) shows a case where the flow path is properly formed, and Pai (i = 1 to 4) is all about 25%. (b) shows that the pressure difference in stroke I is very large. That is, it shows that the flow path is largely closed in the stroke I, and the flow path resistance is very large. This corresponds to the occurrence of a defect in the flow path in step I.
In this case, even if there is no abnormality in the strokes II to IV, it deviates from 25% because the abnormally large pressure difference in the stroke I is used in normalizing the pressure difference. (c) indicates that there is an abnormality in the process II. Also, (d) corresponds to an abnormality in process III. (e) shows that although the pressure difference in the stroke IV is relatively high, even if the flow path is properly formed, it is within the range of variation that occurs. (a) to (e)
The upper limit and the lower limit shown in (1) indicate the range of variation that occurs even when the flow path is properly formed.

The controller 16 determines whether or not all of the standardized pressure differences are below the upper limit and above the lower limit, that is, in the case illustrated in (a) and (e), or
A program for determining whether the case is exemplified in (b) to (d) is incorporated. That is, the upper limit and the lower limit are set as reference values for determination. Then, according to the result, the display 18
Is displayed as OK or NG. According to this inspection device, it is possible to pass OK on a detail in a normal state without overlooking a partial abnormality that is overlooked in the entire inspection, and to display NG if there is an abnormality in a part. Become.

It is preferable that a program for further exchanging the standardized pressure differences Pa1, Pa2, Pa3, and Pa4 be further added to the controller 16 based on the following equation. PAMP1 = Pa1- (Pa2 + Pa3 + Pa4) PAMP2 = Pa2- (Pa3 + Pa4 + Pa1) PAMP3 = Pa3- (Pa4 + Pa1 + Pa2) PAMP4 = Pa4- (Pa1 + Pa2 + Pa3) PAMPi (i = 1 to 4) is calculated as follows.
The value in which the abnormality of the pressure difference is amplified is calculated.
Therefore, when PAMPi is compared with the upper limit and the lower limit, more accurate discrimination becomes possible.

Next, a second embodiment will be described with reference to FIG. The second embodiment differs from the first embodiment in the following points. a. The flow path to be inspected in the first embodiment has the same flow path pattern of 5
Although the arrangement is repeated, the inspection apparatus of this embodiment is designed so as to enable inspection of a flow path where such regularity is not recognized. b. In this embodiment, pressure gauges are provided at all of the outlets so that inspection can be performed for all of the strokes (the stroke is a flow passage between one outlet and another outlet). Can be attached. In addition, an airtight cap can be attached to the outlet that does not require inspection instead of attaching a pressure gauge. FIG. 2 shows the atmosphere opening port 22e and the pump mounting port 22k.
7 shows a state in which pressure gauges P1 to P9 are attached to all other outlets except for. c. In the first embodiment, a pressure difference sensor for detecting a pressure difference is used. In this embodiment, the pressure is detected, and then the pressure difference is calculated and obtained.

In this embodiment, as in the case of the first embodiment, the vacuum pump 32 is operated to detect the pressure at each outlet while the atmosphere is being sucked from the atmosphere opening port 22e. The vacuum pump 32 has a built-in intake air amount adjusting mechanism.
There is no need to use a flow control valve.

The inspection object shown in this embodiment has a very complicated internal flow path.
b, 22f, and 22j, and the outlet 22b communicates with 22c, 22g, and 22i in addition to 22a. A pressure difference is determined for each stroke in accordance with this communication state. That is, the pressure difference ΔP1 in the stroke between the outlets 22a and 22b is determined by the difference between P1 and P2, the pressure difference ΔP2 in the stroke between the outlets 22a and 22f is determined by the difference between P1 and P5, and the stroke between the outlets 22a and 22j Is obtained by the difference between P1 and P9, and the pressure difference ΔP4 in the stroke between the outlets 22b and 22c is P
2 and P3, the pressure difference ΔP5 in the stroke between the outlets 22b and 22g is obtained from the difference between P2 and P6.
The pressure difference ΔP6 in the stroke between b and 22i is determined by the difference between P2 and P8, and so on in the same manner for all the strokes. Note that this calculation is executed by the controller 36, and the controller 36 detects the detection values P1 to P1 of all the pressure gauges.
P9 is input. The pressure difference Δ thus calculated
Each of Pi (i = 1 to 6) is normalized by being divided by the sum of the pressure differences. Standardized pressure difference ΔPai (i = 1
To 6) correspond to the relative pressure difference.

In the case of the first embodiment, the appropriateness of the flow path is determined by utilizing the regularity that the pressure difference is substantially equal because the same flow path pattern is repeated. However, the apparatus according to the second embodiment can inspect a flow path having no regularity. For this purpose, an inspection is performed on an appropriate number of cylinder blocks 22 in which it is known in advance that the flow path is appropriately formed, and data on a standardized pressure difference is collected. As a result, as shown in the lower half of FIG. 2, a range of allowable variation of the standardized pressure difference with respect to a proper product is determined.
The upper line ΔPai (MAX) in the figure indicates the upper limit of the allowable variation, and the lower line ΔPai (MIN) indicates the lower limit. In this case, the upper and lower limits are different for each process because the flow path pattern has no regularity.

The controller 36 is provided with a program for determining whether ΔPai ≦ ΔPai (MAX) and ΔPai ≧ ΔPai (MIN) for all i = 1 to 6.
If this is yes, it is known that the flow path is appropriate in all the steps, and if no, it is known that there is an abnormality in the flow path in at least one of the steps. The result of this determination is displayed on the display 38. In the case of this embodiment, since the reference values Pai (MAX) and Pai (MIN) for judging the suitability are determined from the inspection results of the proper products, the suitability for irregularly arranged flow paths is determined. Is determined.

Next, a third embodiment will be described with reference to FIG. In the third embodiment, the attachment of the inspection device to the molded product 42 is automated. When the molded product 42 is at a predetermined position, the cylinder 66 advances the seal block 46, and the seal block 46 42b is hermetically sealed. Further, the cylinder 70 advances the block 68 to make the flow passage 68a formed in the block 68 communicate with the outlet 42c. Similarly, the cylinder 74 advances the block 72 to make the flow path 72a formed in the block 72 communicate with the outlet 42h. The cylinder 78
Moves the block 76 forward, and makes each of the flow paths 76d, 76e, 72f, 72g formed in the block 76 communicate with each of the outlets 42d, 42e, 42f, 42g. The differential pressure between the flow paths 76d and 76e is equal to the differential pressure sensor P1.
The differential pressure between the flow paths 76e and 72f is detected by the differential pressure sensor P2, and the differential pressure between the flow paths 72f and 72g is detected by the differential pressure sensor P3.

The passage 68a is connected to a vacuum pump 84 via a valve 80, and the passage 72a is connected to a vacuum pump 84 via a valve 82. Valves 80 and 82 are switched to achieve one of the following states. The first state is a state in which the flow path 68a is opened to the atmosphere and the flow path 72a is communicated with the pump 84. In this state, the air flows from the outlets 42c to 42h. The second state is a state in which the flow path 72a is opened to the atmosphere and the flow path 68a is communicated with the pump 84.
In this state, the atmosphere flows from the outlets 42h to 42c.

This inspection apparatus performs an inspection in both of the above states. Then, as shown in the lower section of FIG.
An abnormal differential pressure may not be detected in a state where the air flows from 42h to 42c, but an abnormal differential pressure may be detected in a state where the air flows from 42h to 42c. Or vice versa. This is similar to the flow path 44b in FIG.
Although it greatly contributes to the flow on the side of 2c → 42h, 4
Some flow does not contribute much to the flow from 2h to 42c, or vice versa, as shown in flow path 44e.
This is probably because there is something that does not contribute much to the flow on the side of 2h but greatly contributes to the flow from 42h to 42c. As described above, depending on the shape of the flow path, an abnormality may be overlooked in the one-way inspection, but in this embodiment, since the inspection is performed in both flows, an erroneous inspection is further prevented.
In this embodiment, when at least one of the differential pressures detected when flowing in both directions does not fall within the upper limit and the lower limit, the test result is determined to be "defective".

In the above embodiment, an example in which a vacuum pump is used as a pressure generator has been described. However, the pressure generating device may be a compression pump that generates a high pressure. Even in this case, it is possible to check the suitability of the flow path for each stroke based on whether the differential pressure is normal or abnormal.

[0023]

According to the inspection apparatus of the present invention, the flow path differential pressure stroke while applying a pressure difference is detected, since this is determined as a reference value, normal or abnormal to discriminate about the line In addition, a partial abnormality that is overlooked in the overall inspection can be accurately inspected. In addition, it is easy to make the inspection process unmanned, and it is also possible to maintain the inspection standard at a certain level. Further, according to the present apparatus, it is possible to specify an abnormal portion, and it is extremely easy to take countermeasures.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a first embodiment.

FIG. 2 is a diagram illustrating a second embodiment.

FIG. 3 is a diagram illustrating a third embodiment.

[Explanation of symbols]

 Molded product: 2, 22, 42 Flow path: 4, 24, 44 Outlet: 2a-2l, 22a-22k, 42a-42h Differential pressure sensor: P1, P2, P3 Controller: 16, 36 Sealing cap: 6 For sealing Block: 46

Continuing on the front page (72) Inventor Kazuya Sakai 1-1-1 Asahi-cho, Kariya-shi, Aichi Prefecture Inside Toyota Koki Co., Ltd. 72) Inventor Toyoji Ota 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation (72) Inventor Masaki 1 Toyota Town Toyota City, Aichi Prefecture Inside Toyota Motor Corporation (72) Inventor Hiroyuki Hatakeyama Aichi 1 Toyota Town, Toyota City, Japan Toyota Motor Co., Ltd. Examiner Toru Hongo (56) References JP-A-5-272950 (JP, A) Japanese Utility Model Showa 63-7344 (JP, U) (58) Fields surveyed (Int.Cl. ⁷ , DB name) G01M 19/00 G01B 13/00 G01M 15/00

Claims (1)

(57) [Claims] An apparatus for inspecting whether or not a flow path having a plurality of outlets communicating with the outside is properly formed in a molded article formed so as to be secured therein, a pressure generator which is attached to one outlet of the flow path, and an outlet wherein the pressure generating device is attached, is open to the atmosphere
At least attached to a plurality of outlets, excluding the other one of the exit, means for detecting a pressure difference in the stroke of the flow channel, an outlet open to the atmosphere by operating the pressure generating device large as
Means for comparing the pressure difference detected in a state in which air is flowing with a reference value to determine whether the pressure difference is appropriate or not, and inspecting the flow path in the molded article.