JPS6255541A - Leakage inspection for engine muffler - Google Patents

Abstract

PURPOSE:To reduce the man-hour of inspection, by comparing the first and second leakages to determine whether the compared value is within a predetermined prescribed range. CONSTITUTION:A muffler body 1 is mounted on a first leakage inspection machine 25 and air is injected into the body 1 from a replenishing source 26 and an inspection air source 21 to measure leakage. When the leakage is not within a prescribed range, a lighting 44 is done by a command from a control panel 50 to indicate deficiency. After the repair of the body 1, the leakage is measured again and when it is within the prescribed range, the leakage is sorted by ranks and a paint is sprayed 39-42 to the shell of the body 1 to mark. Then, after the marking, various parts such as exhaust conduit 2 are welded on the body 1 to assemble a muffler 4, which 4 is mounted to a second leakage inspection machine 51. Marks are read with mark detection sensors 70-73 and air is injected 21 into the unit 4 to measure 23 leakage. Then, the leakage measured 23 is compared with the leakage for the marks previously read to judge the acceptance or rejection of the muffler, and thus the man-hour of inspection can be reduced.

Description

Detailed Description of the Invention "Industrial Application Field" The present invention improves inspection accuracy by measuring the amount of leakage twice: once from the muffler main body and when various parts are attached to the muffler main body. The present invention relates to a leakage inspection method for an engine silencer that can improve performance and work efficiency.

``Prior Art'' Generally, as shown in FIG. 5, a silencer used in an automobile includes a silencer 4, which is a silencer main body 1, an exhaust conduit 2 and an exhaust tail pipe 3 attached by welding. A silencing system is constructed by connecting one or more sets such as the silencing device 4a and the main silencing device 4b. As shown in FIGS. 6 and 7, the muffler main body 1 is formed by bending a plate material, spot welding or seaming the joint end 6, and further attaching the body 5 to the body 5. End plate 7
゜8 is tightened. Therefore, the silencer main body 1 cannot be completely airtight because the joints are joined by spot welding or seaming. Product management is performed based on whether the leakage amount that has been set and measured is within the specified range. On the other hand, an exhaust pipe 2 is connected to the muffler main body l.
, exhaust tail pipe 3, hanger 9, 10, etc. are attached by arc welding. The arc welding part 11
If there is an exhaust leak from ゜12,lla, it may cause a serious accident, so welding defects at this location must be completely eliminated.

For this reason, in product management such as the quality of the silencer 4,
Measuring the amount of leakage. To measure the leakage amount of the conventional silencer 4, with the exhaust pipe 2 and the exhaust tail pipe 3 attached to the silencer main body 1, close the opening of either the exhaust pipe 2 or the exhaust tail pipe 3, and close the opening of the other one. Compressed air is injected through the opening, and the product is determined to be good or bad depending on the amount of leakage. In addition, if the muffling device 4 is defective, soapy water may be applied to the arc welding parts 11, 1.
Leak points were confirmed by applying the solution to 2°11a and other locations, or by submerging it in water to generate air bubbles. However, in conventional inspection methods, even if a location with a large amount of leakage is discovered, the inspection is performed with various parts such as the exhaust pipe 2, exhaust tail pipe 3, and hangers 9 and 10 attached to the silencer body 1. Therefore, it is not easy to repair leakage points, and the overall inspection result becomes inaccurate due to leakage from the silencer body 1, making it necessary to check leakage points with soapy water, etc. for all products. On the contrary, it sometimes required a lot of work time.Moreover, each arc between the muffler main body 1, the muffler main body l and the exhaust pipe 2, furthermore the exhaust tail pipe 3, and the hanger 9. There was a problem in that it was not easy to determine the amount of leakage at each location of the welded portions 11, 12° 112.

"Problems to be Solved by the Invention" Therefore, in view of the above circumstances, the present invention first measures leakage points in the muffler main body, and then attaches various parts such as an exhaust pipe, an exhaust tail pipe, and a hanger to the muffler main body. By measuring the leakage amount in the same state and comparing the leakage amounts of both, it is possible to not only confirm the leakage amount at each location, but also improve the inspection accuracy and extremely improve work efficiency.Leakage inspection of engine silencer The purpose is to provide a method.

"Means to be Solved by the Invention" In order to achieve the above object, the present invention measures the amount of leakage by feeding air into the main body of a muffler, and when the amount of leakage is within a predetermined range, the main body of the muffler After displaying the leakage amount,
A silencer is formed by attaching various parts such as the exhaust pipe and exhaust tail pipe, and then air is pumped into the interior to measure the amount of leakage a second time. The present invention is characterized by a leak inspection method for an engine silencer, which compares the first leakage amount and the second leakage amount with respect to a certain silencer, and determines whether or not this comparison value is within a predetermined range. That is.

Embodiment An embodiment of the leakage testing method for an engine silencer according to the present invention will be described below with reference to FIGS. 1 to 4. In FIG. 1, 21 is an inspection air source. Inspection air can be sent from the inspection air source 21 through the pressure control device 22, flow tester 23, and air switching valve 24 into the silencer main body 1 attached to the leakage tester 25 shown in FIG. It looks like this. Flow tester 23 is
The flow rate of air sent from the test air source 21 to keep the air pressure inside the silencer body 1 constant, that is, the amount of leakage, is measured. When measuring this leakage amount, air at a predetermined pressure is injected into the silencer main body 1 from the supplementary air source 26 via the pressure control device 27 and the solenoid valve 28 in advance, and then the solenoid valve 28 is closed. and switch so that air can be injected into the silencer main body 1 from the inspection air source 21,
The injection amount at this time is measured as a leakage amount using a flow tester 23. Immediately before making measurements in this way, connect the auxiliary air source 2 in advance.
Air at a predetermined pressure can be directly injected into the silencer main body 1 from 6 through the flow tester 23 in a short period of time.
Measurements can be performed in an extremely short time.

As shown in FIG. 2, the first leakage tester 25 has a fixed base 31 on which a seal rubber 30 is attached to the lower part of a frame 29, and an aero 32 is attached to the seal rubber 30 and the fixed base 31. It is opened so that air can be injected into the silencer main body 1 from the %if aero 32.

The opening on the other side of the silencer main body 1 is closed with a seal rubber 33a. The seal rubber 33a is attached to a movable base 33 disposed above the fixed base 31. The movable base 33 is fixed to the piston rod 35 of the air cylinder 34, and is configured to clamp the silencer main body l placed on the seal rubber 30 of the fixed base 31 when the air cylinder 34 is driven. . The air cylinder 34 is fixed to the frame 29 via brackets 36 and 37. Frame 2 between fixed base 31 and movable base 33
A window hole 38 is opened in the frame 29, and four marking spray guns 39 to 42 are mounted on the frame 29, facing into the window hole 38.
It is set in. The frame 29 is provided with a start button 43, a patrol light 44, and a paint tank 45. The paint tank 45 uses air from a marking air source to fill the paint in the paint tank 45 with marking spray guns 39 through solenoid valves 46 through 49 shown in FIG.
42 toward the body of the silencer main body 1. The electromagnetic valves 28, 46 to 49, the start button 43, and the patrol light 44 are electrically connected to the control panel 50. Further, the air switching valve 24 also receives a process selection signal from the control panel 50 and performs a switching operation.

Next, after assembling the silencer W4 by attaching various parts such as the exhaust pipe 2, exhaust tail pipe 3, hangers 9 and 10 to the silencer main body l by means of arc welding, the second leakage tester 51 is assembled.
and measure the amount of leakage. When measuring this leakage amount, as shown in FIG. The flow tester 23 is switched so that the magnetic valve 53 is closed and the test air can be sent from the test air source 21 into the silencer 4 via the pressure control device 22, the flow tester 23, and the air switching valve 24. measures the flow rate of air sent from the inspection air source 21 to keep the air pressure in the silencer 4 constant, that is, the amount of leakage.In this way,
If air at a predetermined pressure is directly injected into the silencer 4 from the supplementary air source 52 immediately before the measurement without going through the flow tester 23, the measurement can be carried out in an extremely short time.

The second leakage tester 51 has legs 54 as shown in FIG.
．． The mounting supported by 55 has a plate 56, at each end of which air cylinders 59, 60 are fixed via brackets 57, 58. A presser plate 64 to which a seal rubber 63 is attached via a clamping tool 62 is attached to the piston rod 61 of one air cylinder 59.
is attached, and an aero 65 is opened in the seal rubber 63 and the pressing plate 64. aero 65
is for injecting air into the silencer main body 1 via the exhaust conduit 2 or the exhaust tail pipe 3. An exhaust pipe 2 is connected to the piston rod 6 of the other air cylinder 60.
Or a seal rubber 6 that closes the open end of the exhaust tail pipe 3
7 is provided. For installation, approximately in the center of the plate 56,
The receiver for receiving the muffler main body 1 has members 68 and 69 fixed thereto at appropriate intervals. The receiver is between members 68 and 69,
Mark detection sensors 70 to 73 are provided to read marks displayed on the body of the silencer body l. In addition, the above mounting plate 56 has a receiver member 69 and an air cylinder 6.
A support member 74 for receiving the exhaust tail pipe 3 or the exhaust conduit 2 is provided between the exhaust tail pipe 3 and the exhaust conduit 2 . It is also possible to provide a support member for receiving the exhaust conduit 2 or the exhaust tail pipe 3 on the mounting plate 56 between the receiver member 68 and the air cylinder 59. Furthermore, the mounting plate 56 has a start button 7.
5 and a patrol light 76 are attached. The above solenoid valve 5
3. The mark detection sensors 70 to 73, the start button 75 and the patrol light 76 are electrically connected to the control panel 50 as shown in FIG. Further, the control panel 50 is electrically connected to the flow tester 23 so as to send a detection signal to the flow tester 23 and receive a flow rate signal and a failure signal from the flow tester 23. Of course.

Next, to explain based on the flowchart shown in FIG.
5, press the start button 43 to start the leakage test 7
Do 7. When the start button 43 is pressed, the supplementary air source 26
After air is injected into the muffler main body 1 from the test air source 21, air is injected into the muffler main body 1 from the first
The amount of leakage is measured by the flow tester 23 as a step 78. In the second step 79, it is determined whether the leakage amount is within a predetermined range. If it is within the specified range, proceed to the next third step 8°, and if it is outside the specified range. In a fourth step 81, the patrol light 44 is turned on in response to an instruction from the control panel 50 to indicate a defect, and in a fifth step 82, the defective silencer main body l is repaired or otherwise repaired. Returning to step 78, the leakage amount is measured again. In the third step 80, the amount of leakage within the specified range is ranked into multiple levels, and the control panel 50 opens and closes the solenoid valves 46 to 49 depending on which rank the measured amount of leakage corresponds to. Controlled marking spray gun 39
From 42 to 42, the body 5 of the silencer body 1 is sprayed with paint and marked. Marking spray guns 39-42 are 4
Since each mark is unique, it is possible to classify the marks into 15 ranks based on the combination of the four marks. After marking, in a sixth step 83, various parts such as the exhaust pipe 2, exhaust tail pipe 3, hanger 9° 10, etc. are arc welded to the muffler main body 1 to assemble the muffler 4, and the muffler 4 is assembled.
is attached to the second leakage tester 51 and the start button 75 is pressed. Then, in a seventh step 84, the marks are read by the mark detection sensors 70 to 73, and in an eighth step 85, air is injected into the silencer 4 from the supplementary air source 52, and then air is injected from the inspection air source 21 into the silencer 4. Air is injected into the device 4 and the amount of leakage is measured using the flow tester 23. In the ninth step 86, it is determined whether the leakage amount is within a predetermined range. That is, the ninth step 86 includes arc welding parts 11, 12 . This is to check whether there is a large amount of leakage from places such as lla.

When the leakage amount is within the specified range, the process proceeds to the next 10th step 87, and when the leakage amount is outside the specified range, the patrol light 76 is turned on in the 11th step 88 to indicate a defect, and the 12th step In step 89, the leakage location is confirmed by applying soapy water, etc., and after the leakage location is repaired in a thirteenth step 90, the process returns to the seventh step 84 again. 10th
Step 87 compares the amount of leakage corresponding to the mark read in the seventh step 84 with the amount of leakage measured in the ninth step 86 to determine whether it is good or bad.

That is, the tenth step 87 is the same as the ninth step 86.
It is determined whether the measured leakage amount is within the specific leakage amount rank displayed on the silencer body 1, and if it is within the rank, the leakage test is completed in a fourteenth step 91,
When it is outside the rank, the process proceeds to the eleventh step 88, and returns to the seventh step 84 again via the twelfth step 89 and the thirteenth step 90. Therefore, the tenth step 87 is useful for finding small leaks.

It goes without saying that the determinations in the second step 79, the ninth step 86, and the tenth step 87 are performed by the control panel 5o.

"Effects of the Invention" As described above, according to the leakage testing method for an engine silencer according to the present invention, the main body of the silencer is first tested for leakage, and only non-defective parts are tested by arcing various parts such as the exhaust pipe and the exhaust tail pipe. After installation by welding, a leak test is performed again, so even if a leak is discovered in the second leak test and needs to be repaired, it will only need to be repaired at the location where arc welding was performed, and as a result, repair can be performed extremely easily. Moreover, since the leakage test is carried out twice after the silencer body and various parts are installed, the inspection accuracy is improved, the work of confirming leakage using soapy water is reduced, and the arc welded parts of the silencer body and various parts are each leak,
The amount of leakage can be determined and the number of inspection steps can be reduced, and data on the amount of leakage can be immediately incorporated into the processing process, making quality control easy. There is no operator judgment involved in the mechanical inspection process, so there is no chance of forgetting an inspection or making a mistake due to worker fatigue.Furthermore, by displaying the inspection result data on the silencer itself, it is possible to identify unmeasured and measured items. This makes it easy to classify, prevents unnecessary duplicate measurements, allows inspection of silencers with different specifications, and is suitable for large-scale mass production of a wide variety of types.

[Brief explanation of drawings]

Fig. 1 is an inspection configuration diagram showing an embodiment of the leakage testing method for an engine silencer according to the present invention, Fig. 2 is a perspective view of a first leakage testing machine, and Fig. 3 is a second leakage testing machine. FIG. 4 is a flowchart showing the leakage test procedure, FIG. 5 is a side view of a car equipped with a generally used silencer, FIG. 6 is a perspective view of the silencer, and FIG. , is a cross-sectional view of the silencer. 1... Silencer body 2... Exhaust pipe 3...
Exhaust tail pipe 4... Silencer 11.12...
Arc welding part 21... Inspection air source 23... Flow tester 24... Air switching valve 25... First leak tester 26.52... Replenishment air source 39-42... For marking Spray gun 43.75
... Start button 44.76... Patrol light 50... Control panel 51.
...Second leakage inspection machine 70-73...Mark inspection sensor Patent applicant Hiroshima Press Kogyo Co., Ltd.

Claims (1)

[Claims] Air is pumped into the muffler body to measure the amount of leakage, and after the leakage amount is displayed on the muffler body if it is within a predetermined range, various parts such as the exhaust pipe and exhaust tail pipe are attached. A silencer is formed, and then air is pumped into the interior to measure the second leakage amount, and if the second leakage amount is within a predetermined range, the above-mentioned first leakage amount and second leakage amount are determined. 1. A leakage inspection method for an engine silencer, characterized in that the comparison value is compared with the amount of leakage of the engine, and it is determined whether or not the comparison value is within a predetermined range.