JPH0543046U - Sealing performance inspection device for sealing element - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide an apparatus for inspecting the sealing performance of a sealing element, which can automatically inspect the sealing performance of the sealing element in a short time. A float type flow meter 5 in which an ascending flow corresponding to the sealing performance of the sealing element 2 is generated in the air flow path 5a along with the operation of the vacuum exhaust device 6 and the flow rate value is indicated by a float 5b.
1. A sealing performance inspection device 1 for a sealing element comprising: a portion corresponding to a set flow rate set to be larger than the allowable flow rate based on a reference flow rate change characteristic of an upward flow indicating an allowable limit of the sealing performance of the sealing element 2. A sensor 10 for detecting that the float 5b has passed down and a timer for measuring the elapsed time from the start of the operation of the vacuum exhaust device 6 with the elapsed time corresponding to the set flow rate value as the set time based on the reference flow rate change characteristic. 11, when the signal is input from the sensor 10 and the timer 11 and the detection signal of the sensor 10 is input within the set time of the timer 11, it is determined that the sealing performance of the sealing element 2 is good at that time, and other than that. In this case, the sealing performance inspection device for a sealing element, comprising: a determination device 12 for determining that the sealing performance of the sealing element 2 is defective when the set time of the timer 11 has elapsed.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a sealing performance inspection device for a sealing element, such as an oil seal, an O-ring, a gasket, and a packing, for inspecting the sealing performance of the sealing element.

[0002]

[Prior Art]

 Sealing elements such as oil seals, O-rings, and gaskets cannot achieve sufficient sealing performance if the seal portion that performs the sealing function has defects such as scratches, sink marks, and foreign matter. Therefore, it has been a general practice to visually detect defects such as scratches, sink marks, and foreign matters on the seal portion.

However, the quality of the sealing performance of the sealing element cannot be objectively inspected only by visually inspecting the defect of the seal portion. Therefore, as a device capable of objectively inspecting the sealing performance of the sealing element, a sealing element sealing performance inspection device 20 as shown in FIG. 3 has been developed.

The sealing performance inspection device 20 for sealing performance is for testing the sealing performance of an O-ring which is a sealing element based on flow rate detection using a flow meter. An upper jig 22 and a lower jig 23, a float type flow meter 24 having a float 24b housed in an air passage 24a passing in the vertical direction, and a vacuum exhaust device 25 are provided. Here, the upper jig 22 has a predetermined weight and applies a load necessary for inspection to the O-ring 21, and the lower jig 23 communicates with the inner space 26 of the O-ring 21. The air flow path 23a is formed. The air flow path 23a communicates with the lower part of the air flow path 24a of the float type flow meter 24 via the flow path 27a in the pipe 27, and the upper part of the air flow path 24a is the flow path in the pipe 28. It communicates with the vacuum exhaust device 25 through 28a.

In the conventional sealing performance inspection device 20 for a sealing element having such a configuration, the vacuum exhaust device 25 is actuated to operate the flow path 28 a of the pipe 28, the air flow path 24 a of the float type flow meter 24, and the pipe. Air accumulated in the flow passage 27a of 27, the air flow passage 23a of the lower jig 23, and the inner space 26 of the 0 ring 25 is sucked and discharged to the atmosphere. At that time, the float type flow meter is used. The float 24b of 24 sharply rises due to the large flow rate of the upward flow generated in the air flow path 24a, and eventually descends as the upward flow decreases due to the pressure decrease in the air flow path 24a.

Here, when the O-ring 21 to be inspected has no defects such as scratches, atmospheric air does not leak and flow into the inner space 26 of the O-ring 21, so the float type flow meter As for 24, the ascending flow in the air flow path 24a disappears over time, and the float 24b stops at the lowest position. On the other hand, if the O-ring 21 has a defect such as a flaw, the amount of the atmosphere will leak into the inner space 26 of the O-ring 21 and flow into the inner space 26 of the O-ring 21. The ascending flow in the passage 24a converges on the leak flow rate of the O-ring 21 with the passage of time, and the float 24b stops at the descending / falling position corresponding to the leak flow rate.

FIG. 4 shows the change over time in the indicated value of the float 24b of the float type flow meter 24, that is, in the flow rate of the ascending flow. If the O-ring 21 has no flaws such as scratches, the flow rate is It changes as shown by the solid line to reach zero, but if there is a defect such as a scratch on the O-ring 21, the flow rate changes as shown by the alternate long and short dash line or the broken line, depending on the degree of the O-ring 21 defect. Converges to the leak flow rate. Therefore, if the converged leak flow rate is less than or equal to the allowable flow rate value, it is judged to be acceptable, and if it exceeds the allowable flow rate value, it is judged to be unacceptable and the quality of the sealing performance of the O-ring 21 is inspected.

[0008]

[Problems to be solved by the device]

 By the way, in the sealing performance inspection device 20 according to the conventional example, it takes a considerable time until the float 24b of the float type flow meter 24 stops at a predetermined descending position, that is, the flow rate of the ascending flow converges to the leak flow rate. This is necessary, and there is a problem that the inspection time becomes long as shown by T1, T2 and T3 in FIG.

Further, since the judgment of whether or not the leak flow rate of the O-ring 21 is less than or equal to the allowable flow rate value depends on the visual inspection of the float 24b by the inspector, the automation thereof is demanded.

Therefore, it is an object of the present invention to provide an apparatus for inspecting the sealing performance of a sealing element that can automatically inspect the sealing performance of the sealing element in a short time.

[0011]

[Means for Solving the Problems]

 For this purpose, the device for inspecting the sealing performance of the sealing element according to the present invention creates a rising flow in the air flow path according to the sealing performance of the sealing element in accordance with the operation of the vacuum exhaust device, and indicates the flow rate value by the float. A device for inspecting the sealing performance of a sealing element equipped with a flow meter, the set flow rate being set to a value larger than the allowable flow rate based on the characteristics of the reference flow rate change of the upward flow that indicates the allowable limit of the sealing performance of the sealing element. The sensor that detects when the float has descended and passed through the location corresponding to the above, and the elapsed time corresponding to the set flow rate value based on the reference flow rate change characteristics is set as the set time If a timer that measures time and a signal from the above-mentioned sensor and timer are input and the detection signal of the sensor is input within the set time of the timer, the sealing property of the sealing element at that time Is determined to be good, and in other cases, it is determined that the sealing performance of the sealing element is determined to be poor at the time when the set time of the timer has elapsed, and a determination device for displaying the determination result is provided as a means. There is.

[0012]

[Action]

 By adopting such means, an upward flow is generated in the air flow path of the float type flow meter with the operation of the vacuum exhaust device, the float indicates the flow rate value, and the timer measures the elapsed time. Therefore, when the float descends and passes the location corresponding to the set flow rate value, the sensor outputs a detection signal to the determination device. Here, if the sealing performance of the sealing element is good, the sensor outputs a detection signal within the set time of the timer, so the determination device determines that the sealing performance of the sealing element is good at that time. Then, the judgment result is displayed. If the sealing performance of the sealing element is poor, the sensor does not output the detection signal within the timer setting time. It is judged that there is and the judgment result is displayed.

[0013]

【Example】

 Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 shows a schematic configuration of a sealing performance inspection device 1 according to an embodiment in which an O-ring as a sealing element is an inspection target. The sealing performance inspection device 1 includes a pair of an upper jig 3 and a lower jig 4 that sandwich an O-ring 2, and a float type flow meter 5 that accommodates a float 5b in an air passage 5a that passes vertically. , An evacuation device 6 is provided.

The upper jig 3 has a predetermined weight so as to apply a load required for inspection to the O-ring 2, and the lower jig 4 communicates with the inner space 7 of the O-ring 2. An air flow path 4a is formed. The air flow path 4a communicates with the lower part of the air flow path 5a of the float type flow meter 5 through the flow path 8a in the pipe 8, and the upper part of the air flow path 5a passes through the flow path 9a in the pipe 9. And communicates with the vacuum exhaust device 6.

An intermediate portion in the vertical direction of the float type flow meter 5 is a measuring portion 5c through which the float 5b can be seen, and a portion of the air flow path 5a corresponding to the measuring portion 5c is located above the lower portion. It has a slightly large diameter taper.

Here, a sensor 10 for detecting a descending and descending passage of the float 5b is installed at a predetermined position of the measuring unit 5c of the float type flow meter 5, and the operation is performed in conjunction with the operation of the vacuum exhaust device 6. A timer 11 for starting the measurement of time is provided, and these are connected to the determination device 12. When the detection signal is input from the sensor 10 within the set time of the timer 11, the determination device 12 determines that the sealing performance of the O-ring 2 is good at the time of the input and displays, for example, "OK". If the input of the detection signal from the sensor 10 is slow, it is judged that the sealing performance of the O-ring 2 is defective when the set time of the timer 11 has passed, and for example, "NG" is displayed, or It is configured to alert with a buzzer.

The installation location of the sensor 10 and the set time of the timer 11 are predetermined by the set flow value and the set time T shown in FIG. Here, FIG. 2 shows a change over time in the indicated value of the float 5b of the float type flow meter 5 in accordance with the operation of the vacuum exhaust device 6, that is, the flow rate of the ascending flow generated in the air flow path 5a. When there are no defects such as scratches in 2 and changes to the zero level as shown by the solid line, when there are defects such as scratches in the O-ring 2, it changes to the one-dot chain line or broken line and the O-ring. The leakage flow rate converges according to the degree of defect 2. Here, if the converged leak flow rate is at or below the allowable flow rate as indicated by the one-dot chain line, the sealing performance of the O-ring 2 is good, and if it exceeds the allowable flow rate as indicated by the broken line, the O-ring is shown. The sealing performance of No. 2 may be poor. Therefore, the reference flow rate change characteristic shown by the one-dot chain line in FIG. 2 is used as a reference line, and the elapsed time T corresponding to a predetermined set flow rate value larger than the allowable flow rate value is set as the set time T of the timer 11 to correspond to the above set flow rate value. The sensor 10 is installed at a predetermined position of the weighing unit 5c.

The sealing performance inspecting apparatus 1 for sealing elements of the embodiment having the above-described structure includes the flow passage 9 a of the pipe 9, the air flow passage 5 a of the float type flow meter 5, and the pipe arrangement by the operation of the vacuum exhaust device 6. The air accumulated in the flow passage 8a of No. 8, the air flow passage 4a of the lower jig 4, and the inner space 7 of the O-ring 2 is sucked and discharged to the atmosphere. At that time, the float type flow meter The float 5b of No. 5 abruptly rises by the large flow rate of the ascending flow generated in the air flow path 5a, and eventually descends as the ascending flow decreases due to the pressure decrease in the air flow path 5a.

On the other hand, when the float 5b of the float type flow meter 5 descends and passes a predetermined position of the measuring unit 5c, the sensor 10 outputs the detection signal to the determination device 12. Further, the timer 11 measures the elapsed time from the time of operating the vacuum exhaust device 6 and outputs a signal to the determination device 12. Therefore, when the determination device 12 inputs a detection signal from the sensor 10 within the set time T of the timer 11, the determination device 12 determines that the sealing performance of the O-ring 2 is good at the time of the input and displays, for example, “OK”. If the input of the detection signal from the sensor 10 is slow, it is determined that the sealing performance of the O-ring 2 is defective at the time when the set time T of the timer 11 has elapsed, and for example, "NG" is displayed, Or use a buzzer to alert.

Here, when there is no defect such as a scratch on the O-ring 2 to be inspected or when the defect is minute, the upward flow in the air flow path 5a of the float type flow meter 5 is as shown in FIG. When the flow rate changes between the solid line and the reference line indicated by the alternate long and short dash line, the sensor 10 outputs a detection signal to the determination device 12 within the set time T of the timer 11. Therefore, the determination device 12 determines that the sealing performance of the O-ring 2 is good at the time of inputting the detection signal from the sensor 10, and displays, for example, "OK".

On the other hand, there is a defect that cannot be ignored in the O-ring 2, and the upward flow in the air flow path 5a of the float type flow meter 5 changes on the broken line side from the reference line shown by the one-dot chain line in FIG. In this case, the detection signal of the sensor 10 is not input to the determination device 12 within the set time T of the timer 11. Therefore, the determination device 12 determines that the sealing performance of the O-ring 2 is defective after the elapse of the set time T of the timer 11 and displays, for example, "NG" or warns with a buzzer.

As described above, in the present embodiment, an earlier point than when the ascending flow in the air flow path 5a of the float type flow meter 5 converges on the leak flow rate of the O-ring 2 and the float 5b stops at the descending position, that is, Since the quality of the sealing performance of the O-ring 2 is determined at the latest when the set time T of the timer 11 has elapsed, the inspection time is shortened. Further, the quality of the sealing performance of the O-ring 2 is automatically determined by the determination device 12, and automation is achieved.

In the present embodiment, an example in which the O-ring 2 for flat seal is used as a sealing element for inspection has been described. However, the present invention can be applied to an O-ring for shaft seal, an oil seal, or a packing. It is applicable.

[0024]

[Effect of the device]

 As described above, according to the present invention, an upflow occurs in the air flow path of the float type flow meter due to the operation of the vacuum exhaust device, the float indicates the flow rate value, and the timer measures the elapsed time. Therefore, when the float descends and passes the location corresponding to the set flow rate value, the sensor outputs a detection signal to the determination device. Here, if the sealing performance of the sealing element is good, the sensor outputs a detection signal within the set time of the timer, so the determination device determines that the sealing performance of the sealing element is good at that time. The judgment result is displayed. If the sealing performance of the sealing element is poor, the sensor does not output the detection signal within the set time of the timer, so the judgment device has a poor sealing performance of the sealing element after the elapse of the timer setting time. And the result of the judgment is displayed.

Therefore, the inspection of the sealing performance of the sealing element can be automatically performed in a short time.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing an embodiment of a sealing performance inspection device for a sealing element according to the present invention.

FIG. 2 is a graph showing a change over time in a flow rate instruction value of a flow meter in one example.

FIG. 3 is a schematic configuration sectional view showing a conventional example of a sealing performance inspection device for a sealing element.

FIG. 4 is a graph showing a change over time in a flow rate instruction value of a flow meter in a conventional example.

[Explanation of symbols]

 1, 20 ... Sealing performance inspection device 2, 21 ... O-ring 3, 22 ... Upper jig 4, 23 ... Lower jig 4a, 5a, 23a, 24a ... Air flow path 5 ... Float type flow rate Total 5b, 24b ... Float 5c ... Measuring section 6,25 ... Vacuum exhaust device 7,26 ... Internal space 8,9,27,28 ... Piping 8a, 9a, 27a, 28a ... Flow path 10 ... … Sensor 11 …… Timer 12 …… Judgment device 24 …… Float type liquid level flow meter

Claims (1)

[Scope of utility model registration request] 1. An air flow path (5a) is provided with an ascending flow corresponding to the sealing performance of a sealing element (2) with the operation of a vacuum exhaust device (6).
A sealing performance inspecting device (1) for a sealing element, comprising a float type flow meter (5) for generating a flow rate value therein and indicating the flow rate value by a float (5b), wherein an allowable limit of the sealing performance of the sealing element (2). A sensor (10) for detecting that the float (5b) has descended and passed through a portion corresponding to a set flow rate value set larger than the allowable flow rate value based on the reference flow rate change characteristic of the ascending flow, A timer (11) for measuring the elapsed time from the start of operation of the vacuum exhaust device (6) with the elapsed time corresponding to the set flow rate value as the set time based on the reference flow rate change characteristic, the sensor (10) and the timer ( When the signal is input from 11) and the detection signal of the sensor (10) is input within the set time of the timer (11), it is determined that the sealing performance of the sealing element (2) is good at that time, and other than that. If the timer (11) has passed the set time, the sealing element (2) is determined to have a poor sealing performance and a determination device (12) for displaying the determination result is provided. Element sealing performance inspection device.