Leak Testing with Cylinders

Abstract

The present invention relates to a leak inspection device using a cylinder that injects compressed air into a test object and detects airtight leakage based on a change in pressure. The leak inspection device using the cylinder is structurally improved to set the amount of compressed air injected by controlling the piston travel distance of the compression cylinder part according to the test pressure of the test object, thereby effectively shortening the compressed air injection time and inspection time. It is also configured to ensure measurement pressure accuracy during repeated injection of compressed air by correcting the compressed air supply pressure according to the piston travel distance based on atmospheric pressure. The device is mainly composed of a compression cylinder part (10), an air line (20), and a pressure gauge (30).

Description

Technology Field

[0001] The present invention relates to a leak inspection device using a cylinder, and more specifically, to a leak inspection device using a cylinder that is structurally improved to set the amount of compressed air injected by controlling the piston travel distance of the compression cylinder part in accordance with the inspection pressure of the object to be inspected, thereby effectively shortening the compressed air injection time and inspection time, and can ensure the accuracy of the measurement pressure due to repeated injection of compressed air by correcting the compressed air supply pressure according to the piston travel distance based on atmospheric pressure. Background Technology

[0002] Typically, machined and cast products used as automotive parts and various machine components are mostly products that require airtightness to be guaranteed depending on their function.

[0003] In particular, leak tests must be performed on various component cases (covers), including electric vehicle battery cases and automotive lamp housings, to prevent short circuits caused by moisture penetration.

[0004] Accordingly, in the previously disclosed published patent No. 10-2023-0026821, an apparatus for inspecting air leaks in an object to be inspected, manufactured by die casting and used as a component in an electric vehicle, comprises: a main body frame having a lower frame having a lower base plate, and an upper frame having an upper base plate that is coupled to the upper ends of a plurality of vertical supports connected to the lower base plate and fixedly installed on the upper end of the lower frame; and a seating air block on which the object to be inspected is placed, wherein the air line is formed inside the body and has a sealing member on the outer edge that contacts the lower surface of the object to be inspected, at least one air discharge port is exposed on the upper surface corresponding to the object to be inspected, and an air supply port connected to an air supply line is exposed on the side. A technology has been previously disclosed comprising: a pressurizing unit that pressurizes an object to be inspected downwards to form a sealed space filled with air between the object to be inspected and the mounting air block, by having a pressurizing cylinder fixedly installed vertically on the upper base plate, a plurality of guide rods assembled to be movable vertically on a plurality of guide members provided on the upper base plate, a lifting / lowering platform connected to the lower ends of the plurality of guide rods and connected to the rod tip of the pressurizing cylinder, and a plurality of pressurizing rods installed on the lifting / lowering platform so as to transmit pressurizing force by bringing the upper surface and lower end of the object to be inspected placed on the mounting air block into contact; and a control unit that determines whether the object to be inspected is defective based on changes in the pressure value of the air forcibly supplied to the sealed space.

[0005] However, the aforementioned conventional technology determines whether an object to be inspected is defective based on changes in the pressure of air forcibly supplied into a sealed space. Since the leak test is performed dependent on the pressure supplied over time while the air pressure is controlled by a regulator, it is difficult to supply a constant pressure. Furthermore, pressure deviations occur during the repetitive leak test process depending on external environmental factors, including atmospheric pressure and temperature, leading to a problem where the reliability of the test results cannot be ensured. The problem to be solved

[0006] Accordingly, the present invention is conceived to solve the aforementioned problems, and aims to provide a leak inspection device using a cylinder that can effectively shorten the compressed air injection time and inspection time by improving the structure to set the amount of compressed air injected by controlling the piston travel distance of the compression cylinder part in accordance with the inspection pressure of the object to be inspected, and can ensure the accuracy of the measurement pressure during repeated compressed air injection by correcting the compressed air supply pressure according to the piston travel distance based on atmospheric pressure. means of solving the problem

[0007] To achieve this purpose, the present invention features a leak detection device using a cylinder that injects compressed air into a test object and detects a leak based on a pressure change amount, comprising: a compression cylinder unit (10) configured to control the amount of compressed air output through an output port (12) using the travel distance of a piston (11); an air line (20) configured to deliver the compressed air output through the output port (12) to the test object (A); and a pressure gauge (30) installed on the air line (20) configured to measure the pressure of the compressed air injected into the test object (A) and detect a leak.

[0008] At this time, an input valve (40) is provided to control the on / off of compressed air moving through the output port (12) installed in the above airline (20), and a vent line (50) is provided to be opened and closed by a vent valve (52) installed between the output port (12) and the input valve (40), and after the pressure measurement is completed using the above pressure gauge (30), the input valve (40) and the vent valve (52) are opened to exhaust the compressed air inside the test object (A).

[0009] And, in a leak inspection device using a cylinder that injects compressed air into a test object according to the present invention and detects a leak based on a pressure change amount, the device comprises: a compression cylinder unit (10) configured to control the amount of compressed air output through an output port (12) using the travel distance of a piston (11); a branch pipe (60) configured to distribute and output the compressed air output through the output port (12) to first and second branch ports (61) (62); a first air line (20A) configured to transmit the compressed air output through the first branch port (61) of the branch pipe (60) to the test object (A) side and to be opened and closed by a first input valve (40A); and a second air line (20B) configured to transmit the compressed air output through the second branch port (62) of the branch pipe (60) to a reference tank (T) and to be opened and closed by a second input valve (40B). It is characterized by including a differential pressure gauge (30A) connected to the first and second airlines (20A) (20B) to detect the differential pressure between the internal pressure of the test object (A) and the internal pressure of the reference tank (T).

[0010] In addition, the cylinder part (10) is characterized by being configured to measure atmospheric pressure using an atmospheric pressure measuring sensor (31) and to correct the compressed air supply pressure according to the distance traveled by the piston (11) based on the atmospheric pressure.

[0011] In addition, a temperature sensor (70) is provided to detect the temperature of compressed air introduced into the test object (A), and the measurement pressure value is corrected by reflecting the volume change of the compressed air according to the temperature using the detected value of the temperature sensor (70).

[0012] In addition, the piston (11) of the compression cylinder (10) is characterized by having its travel distance controlled by a servo motor (13), so that the amount of compressed air output through the output port (12) is numerically controlled. Effects of the invention

[0013] According to the above configuration and operation, the present invention is structurally improved to set the amount of compressed air injected by controlling the piston travel distance of the compression cylinder part in accordance with the inspection pressure of the object to be inspected, thereby effectively shortening the compressed air injection time and inspection time, and by correcting the compressed air supply pressure according to the piston travel distance based on atmospheric pressure, it has the effect of ensuring the accuracy of the measurement pressure during repeated injection of compressed air. Brief explanation of the drawing

[0014] FIG. 1 is a schematic diagram showing a leak inspection device using a cylinder according to an embodiment of the present invention. FIG. 2 is a schematic diagram showing a leak inspection device using a cylinder according to another embodiment of the present invention. FIG. 3 is a schematic diagram showing a leak inspection device using a cylinder according to another embodiment of the present invention. FIG. 4 is a flowchart showing the operation sequence of a leak inspection device using a cylinder according to an embodiment of the present invention. Specific details for implementing the invention

[0015] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings.

[0016] FIG. 1 is a schematic diagram showing a leak inspection device using a cylinder according to one embodiment of the present invention, FIG. 2 is a schematic diagram showing a leak inspection device using a cylinder according to another embodiment of the present invention, FIG. 3 is a schematic diagram showing a leak inspection device using a cylinder according to another embodiment of the present invention, and FIG. 4 is a flowchart showing the operation sequence of a leak inspection device using a cylinder according to one embodiment of the present invention.

[0017] The present invention relates to a leak inspection device using a cylinder that injects compressed air into a test object and detects airtight leakage based on a change in pressure. The leak inspection device using the cylinder is structurally improved to set the amount of compressed air injected by controlling the piston travel distance of the compression cylinder part according to the test pressure of the test object, thereby effectively shortening the compressed air injection time and inspection time. It is also configured to ensure measurement pressure accuracy during repeated injection of compressed air by correcting the compressed air supply pressure according to the piston travel distance based on atmospheric pressure. The device is mainly composed of a compression cylinder part (10), an air line (20), and a pressure gauge (30).

[0018] The compression cylinder part (10) according to the present invention is configured to control the amount of compressed air output through the output port (12) by utilizing the travel distance of the piston (11).

[0019] The above compression cylinder section (10) is a device for injecting compressed air into the inspection object (A), and is configured so that air prepared inside the compression cylinder section (10) is output through the output port (12) in proportion to the travel distance of the piston (11).

[0020] At this time, the compression cylinder part (10) controls the travel distance of the piston (11) to match the inspection pressure of the object to be inspected (A) and sets the amount of compressed air injected, thereby having the advantage of effectively shortening the inspection time as well as shortening the compressed air injection time.

[0021] Additionally, the cylinder part (10) is configured to measure atmospheric pressure using an atmospheric pressure measuring sensor (31) and to correct the compressed air supply pressure according to the distance traveled by the piston (11) based on the atmospheric pressure.

[0022] As such, the above cylinder part (10) finely adjusts the piston (11) by reflecting atmospheric pressure, so there is an advantage in that the measurement pressure accuracy can be secured through repeated injection of compressed air.

[0023] In addition, the airline (20) according to the present invention is configured to deliver compressed air output through the output port (12) to the test object (A).

[0024] The above air line (20) is an air passage connecting the compression cylinder part (10) and the object to be inspected (A), with one end connected to the output port (12) and the other end connected to the object to be inspected (A).

[0025] In addition, the pressure gauge (30) according to the present invention is installed in the airline (20) to measure the pressure of compressed air injected into the test object (A) and to detect airtight leakage.

[0026] The above pressure gauge (30) is configured to detect changes in internal pressure of the test object (A) after compressed air is injected into the test object (A), and the detected value is transmitted to the control unit for calculation and management.

[0027] In FIG. 2, an input valve (40) is provided to control the on / off of compressed air moving through the output port (12) installed in the airline (20), and a vent line (50) is provided to be opened and closed by a vent valve (52) installed between the output port (12) and the input valve (40).

[0028] In addition, after the pressure measurement is completed using the pressure gauge (30), the input valve (40) and the vent valve (52) are opened to exhaust the compressed air inside the test object (A), thereby providing the advantage of improved workability when replacing the test object (A).

[0029] In FIG. 3, a leak inspection device using a cylinder that injects compressed air into a test object according to the present invention and detects a leak based on a pressure change amount comprises a compression cylinder part (10), a branch pipe (60), a first air line (20A), a second air line (20B), and a differential pressure gauge (30A) as its main components.

[0030] The compression cylinder part (10) according to the present invention is configured to control the amount of compressed air output through the output port (12) by utilizing the travel distance of the piston (11).

[0031] The above compression cylinder section (10) is a device for injecting compressed air into the inspection object (A), and is configured so that air prepared inside the compression cylinder section (10) is output through the output port (12) in proportion to the travel distance of the piston (11).

[0032] At this time, the compression cylinder part (10) controls the travel distance of the piston (11) to match the inspection pressure of the object to be inspected (A) and sets the amount of compressed air injected, thereby having the advantage of effectively shortening the inspection time as well as shortening the compressed air injection time.

[0033] Additionally, the cylinder part (10) is configured to measure atmospheric pressure using an atmospheric pressure measuring sensor (31) and to correct the compressed air supply pressure according to the distance traveled by the piston (11) based on the atmospheric pressure.

[0034] As such, the above cylinder part (10) finely adjusts the piston (11) by reflecting atmospheric pressure, so there is an advantage in that the measurement pressure accuracy can be secured through repeated injection of compressed air.

[0035] In addition, the branch pipe (60) according to the present invention is configured to distribute compressed air output through the output port (12) to the first and second branch ports (61) (62).

[0036] The above branch pipe (60) is configured to divide the compressed air output from the compression cylinder section (10) into two and supply it to the test object (A) and the reference tank (T).

[0037] That is, the compressed air branched to the first branch port (61) of the above branch pipe (60) is transferred to the test object (A), and the compressed air branched to the second branch port (62) is transferred to the reference tank (T).

[0038] In addition, the first airline (20A) according to the present invention is configured to transmit compressed air output through the first branch port (61) of the branch pipe (60) to the side of the object to be inspected (A), and to be opened and closed by the first input valve (40A).

[0039] In addition, the second airline (20B) according to the present invention is configured to transmit compressed air output through the second branch port (62) of the branch pipe (60) to the reference tank (T) and to be opened and closed by the second input valve (40B).

[0040] And, the first input valve (40A) and the second input valve (40B) are provided to be turned on / off by a control unit.

[0041] In addition, the differential pressure gauge (30A) according to the present invention is connected to the first and second airlines (20A) (20B) and is configured to detect the differential pressure between the internal pressure of the test object (A) and the internal pressure of the reference tank (T).

[0042] The above differential pressure gauge (30A) is configured to detect the differential pressure between the internal pressure of the test object (A) and the reference tank (T) after the first and second input valves (40A) (40B) are turned off when the pressure stabilizes while compressed air is injected into the test object (A) and the reference tank (T) through the first and second air lines (20A) (20B), and to determine that there is a leak if the differential pressure value deviates from the set range.

[0043] In addition, a temperature sensor (70) is provided to detect the temperature of the compressed air introduced into the test object (A).

[0044] By utilizing the detection value of the temperature sensor (70), the measurement pressure value is corrected by reflecting the volume change of compressed air according to temperature, thereby having the advantage of improving the reliability of the measurement result without being affected by the external environment.

[0045] In addition, the piston (11) of the compression cylinder (10) is configured such that its travel distance is controlled by a servo motor (13), thereby allowing the amount of compressed air output through the output port (12) to be numerically controlled.

[0046] As such, the compressed air output pressure is corrected by the movement distance of the piston (11) by the above-mentioned servo motor (13), thereby flexibly responding to external environments including atmospheric pressure and temperature to improve measurement precision, and in particular, versatility is provided to inspect test objects (A) of different volumes by simply changing the setting to correct the movement distance of the piston (11). Explanation of the symbols

[0047] 10: Compression cylinder section 20: Airline 30: Pressure gauge

Claims

Claim 1 A leak inspection device using a cylinder that injects compressed air into a test object and detects a leak based on a pressure change amount, comprising: a compression cylinder unit (10) configured to set the amount of compressed air injected through an output port (12) by controlling the travel distance of a piston (11) in accordance with the test pressure of the test object; and an air line (20) configured to deliver the compressed air output through the output port (12) to the test object (A). A leak inspection device using a cylinder, comprising: a pressure gauge (30) installed in the above airline (20) to measure the pressure of compressed air injected into the object to be inspected (A) and to detect a leak; wherein the compression cylinder part (10) is configured to measure atmospheric pressure using an atmospheric pressure measuring sensor (31) and to correct the compressed air supply pressure according to the distance traveled by the piston (11) based on the atmospheric pressure, and is configured to have a temperature sensor (70) that detects the temperature of the compressed air injected into the object to be inspected (A), and is configured to correct the measured pressure value by reflecting the volume change of the compressed air according to the temperature using the detection value of the temperature sensor (70). Claim 2 A leak inspection device using a cylinder according to claim 1, characterized in that an input valve (40) is provided to control the on / off of compressed air moving through the output port (12) installed in the airline (20), a vent line (50) is provided installed between the output port (12) and the input valve (40) and is opened and closed by a vent valve (52), and after pressure measurement is completed using the pressure gauge (30), the input valve (40) and the vent valve (52) are opened to exhaust the compressed air inside the object to be inspected (A). Claim 3 In a leak inspection device using a cylinder that injects compressed air into a test object and detects airtight leakage based on a pressure change amount, the device comprises: a compression cylinder unit (10) configured to set the amount of compressed air injected through an output port (12) by controlling the travel distance of a piston (11) in accordance with the test object inspection pressure; a branch pipe (60) configured to distribute and output the compressed air output through the output port (12) to first and second branch ports (61)(62); a first air line (20A) configured to transmit the compressed air output through the first branch port (61) of the branch pipe (60) to the test object (A) side and to be opened and closed by a first input valve (40A); and a second air line configured to transmit the compressed air output through the second branch port (62) of the branch pipe (60) to a reference tank (T) and to be opened and closed by a second input valve (40B). A leak inspection device using a cylinder, comprising: a second airline (20B); and a differential pressure gauge (30A) connected to the first and second airlines (20A) (20B) for detecting the differential pressure between the internal pressure of the object to be inspected (A) and the internal pressure of the reference tank (T); wherein the compression cylinder part (10) is configured to measure atmospheric pressure using an atmospheric pressure measuring sensor (31) and to correct the compressed air supply pressure according to the distance traveled by the piston (11) based on the atmospheric pressure, and is configured to have a temperature sensor (70) for detecting the temperature of the compressed air introduced into the object to be inspected (A), and is configured to correct the measured pressure value by reflecting the volume change of the compressed air according to the temperature using the detection value of the temperature sensor (70). Claim 4 delete Claim 5 delete Claim 6 A leak inspection device using a cylinder according to claim 1 or 3, wherein the compression cylinder part (10) includes a servo motor (13) configured to move a piston (11), and the servo motor (13) is configured to control the travel distance of the piston (11) in accordance with the inspection pressure of the object to be inspected and to set the amount of compressed air injected through the output port (12).

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