JP4764716B2 - Heat exchanger pressure resistance inspection method and pressure resistance inspection device - Google Patents

Description

  In the present invention, a plurality of hollow refrigerant circulation portions having internal joints are provided in parallel, and a gap is provided between adjacent refrigerant circulation portions, and fins are disposed in the ventilation gap. The present invention relates to a pressure resistance inspection method and a pressure resistance inspection apparatus for a heat exchanger.

  In this specification, the term “aluminum” includes aluminum alloys in addition to pure aluminum.

  As a heat exchanger, a pair of aluminum headers arranged parallel to each other at intervals, and a plurality of hollow refrigerant circulation portions arranged in parallel between both headers and having both ends connected to both headers, respectively. A flat heat exchange pipe made of aluminum and an aluminum corrugated fin brazed to both heat exchange pipes and disposed in a ventilation gap between adjacent heat exchange pipes are widely used. .

  The flat heat exchange tube is, for example, two flat walls parallel to each other, both side walls straddling both side edges of both flat walls, and extends between the two side walls and extends in the length direction and has a predetermined distance from each other. And a plurality of reinforcing walls provided in parallel, and having parallel fluid passages therein, and each reinforcing wall is integrally formed in an upwardly protruding shape from one flat wall The ridges for reinforcing wall and the ridges for reinforcing wall integrally formed in an inwardly protruding shape from the other flat wall are brazed against each other and brazed to each other. A device in which the portion is an internal joint is known (see Patent Document 1).

  By the way, in the heat exchanger having the flat heat exchanger tube described above, the reinforcing wall projections have sufficient brazing strength without causing brazing defects in order to obtain necessary pressure resistance. It must be brazed.

However, it is not possible to easily know the brazing part of the reinforcing wall convex stripes, that is, the occurrence of brazing failure of the internal joint, and the strength of the reinforcing wall convex stripes, and as a result heat exchange At present, it is not possible to easily check the pressure resistance of the vessel.
JP-A-6-281373

  The present invention has been made in view of the above circumstances, and provides a heat exchanger pressure resistance inspection method and a pressure resistance inspection device capable of inspecting the pressure resistance of a heat exchanger relatively easily and accurately. With the goal.

The present invention comprises the following modes in order to achieve the above object.

1) Heat in which a plurality of hollow refrigerant circulation portions having internal joint portions are provided in parallel, and between adjacent refrigerant circulation portions are ventilation gaps and fins are arranged in the ventilation gaps. A method for inspecting the pressure resistance of an exchanger,
The heat exchanger is irradiated with light from one side of the ventilation direction, the heat exchanger is imaged by the imaging means from the opposite side of the ventilation direction, the imaging range is divided into a plurality of dots, and based on the luminance information at each dot Obtain the brightness information of the imaging range, then pressurize the inside of the heat exchanger, and after starting the pressurization, continuously image the heat exchanger from the opposite side of the ventilation direction with the imaging means and divide the imaging range into multiple dots In addition, the luminance information of the imaging range is obtained based on the luminance information in each dot, and the heat exchanger of the heat exchanger is determined based on the continuous change in the luminance information of the imaging range before pressurization and the luminance information of the imaging range after pressurization. A pressure resistance inspection method for a heat exchanger, characterized by determining pressure resistance.

2) The pressure resistance test method for a heat exchanger according to 1) above, wherein the pressure inside the heat exchanger is controlled based on a continuous change in luminance information of the imaging range after pressurization.

3) A monochrome image is obtained by imaging the heat exchanger by the imaging means, the monochrome image is subjected to gray processing, and luminance information at each dot is binarized into a white portion and a black portion by a predetermined threshold value. Counting the number of black parts and determining the pressure resistance of the heat exchanger based on the continuous change in the number of black parts before pressurization and the number of black parts after pressurization in the imaging range 1) or 2 ) The pressure resistance test method of the heat exchanger described.

4) A monochrome image is obtained by imaging the heat exchanger by the imaging means, the monochrome image is subjected to gray processing, and luminance information in each dot is binarized into a white portion and a black portion by a predetermined threshold value, extracting a pattern of white portions and black portions in the imaging range, the pattern before pressurization, and after pressurization pattern continuously changes determines the 1 pressure resistance of the heat exchanger based on the) to 3) of the The pressure-resistant test | inspection method of the heat exchanger in any one of.

5) Heat in which a plurality of hollow refrigerant circulation portions having internal joints are provided in parallel, and between adjacent refrigerant circulation portions are ventilation gaps and fins are arranged in the ventilation gaps. A method for inspecting the pressure resistance of an exchanger,
The heat exchanger is irradiated with light from one side of the ventilation direction, the heat exchanger is imaged by the imaging means from the opposite side of the ventilation direction, the imaging range is divided into a plurality of dots, and based on the luminance information at each dot To obtain brightness information of the imaging range, then pressurize the inside of the heat exchanger, and after the start of pressurization, intermittently capture the heat exchanger with the imaging means from the opposite side of the ventilation direction and divide the imaging range into multiple dots In addition, the luminance information of the imaging range is obtained based on the luminance information at each dot, and the heat exchanger's luminance information of the imaging range before pressurization and the intermittent change of the luminance information of the imaging range after pressurization A pressure resistance inspection method for a heat exchanger, characterized by determining pressure resistance.

6) The heat exchanger pressure resistance test method according to 5) above, wherein the pressure inside the heat exchanger is controlled on the basis of intermittent changes in luminance information of the imaging range after pressurization.

7) A monochrome image is obtained by imaging the heat exchanger with the imaging means, the monochrome image is subjected to gray processing, and luminance information at each dot is binarized into a white portion and a black portion by a predetermined threshold value. Count the number of black parts, and determine the pressure resistance of the heat exchanger based on the intermittent change in the number of black parts before pressurization and the number of black parts after pressurization in the imaging range 5) or 6 ) The pressure resistance test method of the heat exchanger described.

8) A monochrome image is obtained by imaging the heat exchanger by the imaging means, the monochrome image is subjected to gray processing, and luminance information in each dot is binarized into a white portion and a black portion by a predetermined threshold value, extracting a pattern of white portions and black portions in the imaging range, the pattern before pressurization, and the 5 judges the pressure resistance of the heat exchanger on the basis of the intermittent change in the pattern of post-compression) to 7) of the The pressure-resistant test | inspection method of the heat exchanger in any one of.

9) A plurality of hollow refrigerant circulation portions having internal joints are provided in parallel between a pair of headers arranged at intervals, and ventilation is provided between adjacent refrigerant circulation portions. An apparatus for inspecting the pressure resistance of a heat exchanger in which fins are arranged in a ventilation gap as well as a gap,
Imaging the heat exchanger from the pressurizing means that pressurizes the inside of the heat exchanger, the light irradiating means that is disposed on one side of the heat exchanger in the ventilation direction and that irradiates light to the heat exchanger, and the opposite side of the light irradiating means Before and after pressurization by the pressurizing unit, the imaging range by the imaging unit is divided into a plurality of dots, and luminance information of the imaging range is obtained based on the luminance information of each dot, and the luminance of the imaging range Processing means for determining the pressure resistance of the heat exchanger based on information, and the processing means continuously or intermittently changes the luminance information of the imaging range before pressurization and the luminance information of the imaging range after pressurization. Pressure resistance inspection device for heat exchanger that determines the pressure resistance of the heat exchanger based on the above.

10) The heat exchanger according to 9) above, wherein the processing means controls the pressurizing force inside the heat exchanger by the pressurizing means based on continuous change or intermittent change in luminance information of the imaging range after pressurization. Pressure resistance inspection device.

11) The processing means performs gray processing on the monochrome image obtained by imaging the heat exchanger by the imaging means, and binarizes the luminance information at each dot into a white portion and a black portion with a predetermined threshold value. And the number of black portions is counted, and the pressure resistance of the heat exchanger is determined based on continuous or intermittent change in the number of black portions before pressurization and the number of black portions after pressurization in the imaging range. 9) or 10) the pressure resistance test apparatus for heat exchangers.

12) The processing means performs gray processing on the monochrome image obtained by imaging the heat exchanger by the imaging means, and binarizes the luminance information at each dot into a white portion and a black portion by a predetermined threshold value. The above-mentioned 9) to extract the white and black pattern in the imaging range and determine the pressure resistance of the heat exchanger based on the continuous change or intermittent change of the pattern before pressurization and the pattern after pressurization The pressure resistance test apparatus for a heat exchanger according to any one of 11) .

13) The pressure resistance test apparatus for a heat exchanger according to any one of 9) to 12) above, wherein the pressurizing means is a high pressure air supply device for supplying high pressure air into the heat exchanger.

14) The heat exchanger pressure resistance inspection apparatus according to any one of 9) to 13) , wherein the imaging means is a CCD camera.

15) The pressure resistance test for the heat exchanger according to any one of 9) to 13) above, wherein the imaging means is composed of a line sensor and includes moving means for relatively moving the line sensor and the heat exchanger. apparatus.

16) The heat exchanger pressure resistance inspection apparatus according to any one of 9) to 15) , wherein the processing means is an image processing apparatus .

17) A heat exchanger production line provided with the pressure resistance test apparatus according to any one of 9) to 16 ) above.

According to the above methods 1) and 3) , when a poor bonding occurs in the internal joint portion of the hollow refrigerant circulation portion, or when the joint strength of the internal joint portion is insufficient, the heat exchanger When the inside is pressurized, the internal joint part is broken and the refrigerant circulation part is deformed so as to be greatly expanded, and the fins arranged in the ventilation gap are greatly deformed. In this case, the luminance information in the imaging range changes greatly compared to that before pressurization. On the other hand, if no poor bonding occurs in the internal joint portion of the hollow refrigerant circulation portion and the joint strength of the internal joint portion is sufficiently large, even if the inside of the heat exchanger is pressurized, the refrigerant circulation portion The fins are not greatly deformed, and the luminance information in the imaging range after pressurization hardly changes compared to that before pressurization. Therefore, the pressure resistance of the heat exchanger can be determined based on the luminance information of such an imaging range, and as a result, the pressure resistance of the heat exchanger can be easily and accurately inspected. In addition, oversight due to human error in visual inspection and stable inspection independent of the ability of the inspector are possible. In addition, when the inside of the heat exchanger is pressurized, the refrigerant circulation part and the fin are slightly deformed even when the internal joint does not break, but based on the continuous change of the luminance information in the imaging range after pressurization In addition, the deformation start pressure and the deformation end pressure of the refrigerant flow section and the fin can be known, and the pressure resistance of the heat exchanger can be inspected in more detail. In addition, based on the relationship between the continuous change in luminance information in the imaging range and the applied pressure, the type of joint defect at the internal joint of the hollow coolant circulation part can be known, and measures are taken to eliminate the joint defect. be able to. Furthermore, when the bonding strength of the internal joint of the refrigerant circulation part is extremely low, the refrigerant circulation part may be destroyed at a stroke before the internal pressure reaches the set value. Fracture pressure can be assumed from the correlation between the continuous change of luminance information and internal pressure. In addition, when the change in luminance information in the imaging range reaches a certain limit, it is possible to prevent the inspection apparatus from being damaged due to the destruction of the entire heat exchanger by stopping the internal pressurization.

According to the method 2), the pressure resistance can be inspected without destroying the heat exchanger.

According to the method 4) , in addition to the effects of the methods 1) and 3) , the following effects can be obtained. That is, when the inside of the heat exchanger is pressurized, the luminance information of the imaging range due to the large deformation of the refrigerant circulation part and the fin due to the breakage of the internal joint part of the hollow refrigerant circulation part, that is, the pattern of the white part and the black part In addition to the change, the pattern of the white part and the black part of the imaging range may occur due to the deformation and warpage of the entire heat exchanger and the flickering of light. However, the white part and black part patterns resulting from deformation of the refrigerant circulation part and the fins due to the breakage of the internal joint part of the hollow refrigerant circulation part, and the white part due to deformation of the whole heat exchanger and warping and flickering of light And the black part pattern are different from each other. Therefore, based on the continuous change of the pattern before pressurization and the pattern after pressurization, deformation of the refrigerant circulation part and fins, or deformation and warpage of the entire heat exchanger And whether the light flickers or not, and the accuracy of the pressure resistance test is increased.

According to the above methods 5) and 7) , when a poor bonding occurs in the internal joint portion of the hollow refrigerant circulation portion, or when the joint strength of the internal joint portion is insufficient, the heat exchanger When the inside is pressurized, the internal joint part is broken and the refrigerant circulation part is deformed so as to be greatly expanded, and the fins arranged in the ventilation gap are greatly deformed. In this case, the luminance information in the imaging range changes greatly compared to that before pressurization. On the other hand, if no poor bonding occurs in the internal joint portion of the hollow refrigerant circulation portion and the joint strength of the internal joint portion is sufficiently large, even if the inside of the heat exchanger is pressurized, the refrigerant circulation portion The fins are not greatly deformed, and the luminance information in the imaging range after pressurization hardly changes compared to that before pressurization. Therefore, the pressure resistance of the heat exchanger can be determined based on the luminance information of such an imaging range, and as a result, the pressure resistance of the heat exchanger can be easily and accurately inspected. In addition, oversight due to human error in visual inspection and stable inspection independent of the ability of the inspector are possible. Further, when the inside of the heat exchanger is pressurized, the refrigerant circulation part and the fin are slightly deformed even when the internal joint is not broken, but based on the intermittent change of the luminance information in the imaging range after pressurization. In addition, the deformation start pressure and the deformation end pressure of the refrigerant flow section and the fin can be known, and the pressure resistance of the heat exchanger can be inspected in more detail. Also, based on the relationship between the intermittent change in the luminance information of the imaging range and the applied pressure, the type of joint defect at the internal joint of the hollow coolant circulation part can be known, and measures are taken to eliminate the joint defect. be able to. Furthermore, when the bonding strength of the internal joint of the refrigerant circulation part is extremely low, the refrigerant circulation part may be destroyed at a stroke before the internal pressure reaches the set value. Fracture pressure can be assumed from the correlation between the intermittent change of luminance information and internal pressure. In addition, when the change in luminance information in the imaging range reaches a certain limit, it is possible to prevent the inspection apparatus from being damaged due to the destruction of the entire heat exchanger by stopping the internal pressurization.

According to the method 6), the pressure resistance can be inspected without destroying the heat exchanger.

According to the above method 8) , the following effects can be obtained in addition to the effects of the above methods 5) and 7) . That is, when the inside of the heat exchanger is pressurized, the luminance information of the imaging range due to the large deformation of the refrigerant circulation part and the fin due to the fracture of the internal joint part of the hollow refrigerant circulation part, that is, the pattern of the white part and the black part In addition to the change, the pattern of the white part and the black part of the imaging range may occur due to the deformation and warpage of the entire heat exchanger and the flickering of light. However, the white part and black part patterns resulting from deformation of the refrigerant circulation part and the fins due to the breakage of the internal joint part of the hollow refrigerant circulation part, and the white part due to deformation of the whole heat exchanger and warping and flickering of light And the black part pattern are different from each other, based on the intermittent change of the pattern before pressurization and the pattern after pressurization, the deformation of the refrigerant circulation part and fins, or the deformation and warpage of the entire heat exchanger And whether the light flickers or not, and the accuracy of the pressure resistance test is increased.

When the pressure resistance of the heat exchanger is inspected using the apparatus of 9), the same effects as those of the methods 1) and 5) are obtained.

When the pressure resistance of the heat exchanger is inspected using the apparatus 10), the same effects as in the methods 2) and 6) are obtained.

When the pressure resistance of the heat exchanger is inspected using the apparatus of 11), the same effects as those of the methods of 3) and 7) are obtained.

When the pressure resistance of the heat exchanger is inspected using the apparatus of 12), the same effects as those of the methods 4) and 8) are obtained.

According to the apparatus 14) , the cost of the imaging means is relatively low.

  Embodiments of the present invention will be described below with reference to the drawings. In the following description of the refrigerant circulation part of the heat exchanger, the upper and lower sides and the left and right sides in FIGS.

  FIG. 1 shows an example of a heat exchanger whose pressure resistance is inspected by the method of the present invention, and FIG. 2 shows an example of a flat heat exchange pipe as a refrigerant circulation part used in this heat exchanger. 3 shows a method for producing the flat heat exchange tube shown in FIG.

  In FIG. 1, a heat exchanger (1) is used as a condenser for a car air conditioner. A pair of headers (2) (3) and a pair of headers (2) ( 3) Adjacent heat exchange with a plurality of aluminum flat heat exchange tubes (4) (hollow refrigerant circulation section) arranged in parallel between both ends and connected to both headers (2) and (3) respectively. Located in the ventilation gap (5) between the tubes (4) and connected to the aluminum corrugated fins (6) brazed to both heat exchange tubes (4) and the upper end of the peripheral wall of the first header (2) The inlet pipe (7), the outlet pipe (8) connected to the lower end of the peripheral wall of the second header (3), and the first provided in the upper position above the middle of the first header (2). A partition plate (9) and a second partition plate (10) provided in a lower position in the middle of the second header (3) are provided, and the heat above the first partition plate (9) is provided. Number of exchange pipes (4), first finish The number of heat exchange pipes (4) between the cut plate (9) and the second partition plate (10) and the number of heat exchange pipes (4) below the second partition plate (10) are sequentially reduced from above. The gas phase refrigerant flowing in from the inlet pipe (7) flows through the outlet pipe (8) as a liquid phase and flows out into the heat exchanger (1). It is made to flow in a meandering manner in the county unit.

  As shown in FIG. 2, the flat heat exchange pipe (4) has flat upper and lower walls (11) and (12) (a pair of flat walls) facing each other, and both left and right sides of the upper and lower walls (11) and (12). The left and right side walls (13) and (14) straddling the edges and the left and right side walls (13) and (14) span the upper and lower walls (11) and (12) and extend in the length direction with a predetermined distance from each other. It consists of a plurality of reinforcing walls (15) provided, and has a plurality of parallel fluid passages (16) inside. Although not shown in the figure, all the reinforcing walls (15) are provided with a plurality of communication holes through which adjacent fluid passages (16) pass so as to form a staggered arrangement as viewed from above. Yes.

  The left side wall (13) is integrally formed in a protruding shape for the side wall (17) integrally formed in a protruding shape downward from the left side edge of the upper wall (11) and in a protruding shape in the upward direction from the left side edge of the lower wall (12). Side wall ridges (18) are formed by being butted against each other. The right side wall (14) is formed integrally with the upper and lower walls (11) (12).

  The reinforcing wall (15) is a reinforcing wall ridge (19) integrally formed in a raised shape below the upper wall (11), and a reinforcing wall ridge integrally formed in a raised shape above the lower wall (12). (20) are brazed against each other, and the brazed portion between the reinforcing wall projections (19) and (20) is an internal joint.

  The flat heat exchange tube (4) is manufactured using a metal plate (25) for manufacturing a flat heat exchange tube as shown in FIG. The flat heat exchanger tube manufacturing metal plate (25) is made of an aluminum brazing sheet having a brazing filler metal layer on both sides, and includes a flat upper wall forming part (26) (flat wall forming part) and a lower wall forming part (27) ( A flat wall forming part), an upper wall forming part (26) and a lower wall forming part (27), and a connecting part (28) forming a right side wall (14); an upper wall forming part (26) and a lower wall forming part; Side wall protrusions (17) and (18) integrally formed in a raised shape above the side edge of the wall forming part (27) opposite to the connecting part (28) and forming the left side wall (13), and the left-right direction And a plurality of reinforcing wall ridges (19) and (20) integrally formed in a raised shape above the upper wall forming portion (26) and the lower wall forming portion (27) at a predetermined interval, The reinforcing wall ridges (19) of the upper wall forming portion (26) and the reinforcing wall ridges (20) of the lower wall forming portion (27) are located symmetrically with respect to the center line in the width direction. . The heights of the ridges for both side walls (17) and (18) and all the ridges for reinforcing walls (19) and (20) are equal. Bending and positioning ridges (29) are integrally formed over the entire length of most of the connecting portion (28) except for the left and right side edges.

  The side wall protrusions (17), (18) and the reinforcing wall protrusions (19), (20) are integrally formed on one side of the aluminum brazing sheet clad with the brazing material on both sides, thereby forming the side wall protrusions. A brazing filler metal layer (not shown) is formed on both side surfaces and tip surfaces of the strips (17) and (18) and the reinforcing wall projections (19) and (20) and on both upper and lower surfaces of the upper and lower wall forming portions (26) and (27). However, the brazing filler metal layers on the front end faces of the side wall ridges (17) and (18) and the reinforcing wall ridges (19) and (20) are thicker than the brazing filler metal layers in the other portions. Further, a protrusion (31) extending in the longitudinal direction is integrally formed over the entire length on the front end surface of the side wall protrusion (18) in the lower wall forming portion (27). On the other hand, a concave groove (32) extending in the longitudinal direction and into which the protrusion (31) is press-fitted is formed over the entire length on the front end surface of the side wall protrusion (17) in the upper wall forming portion (26). A brazing filler metal layer is also present on the tip surface and both side surfaces of the protrusion (31) and on the bottom surface and both side surfaces of the groove (32).

  Then, the metal plate (25) for manufacturing the flat heat exchange tube is sequentially bent at the right and left side edges of the connecting portion (28) by the roll forming method using the bending positioning projection (29) (FIG. 3). (Refer to (b)), and finally fold it into a hairpin shape to butt the ridges for side walls (17) and (18) and the ridges for reinforcing walls (19) and (20), respectively, and dent the protrusions (31). Press-fitted into the groove (32) to form a bent body (33) (see FIG. 3 (c)), the tips of the side wall ridges (17) and (18) and the reinforcing wall ridges (19) and (20) The flat heat exchange tubes (4) are manufactured by brazing the tip portions of the two. At this time, the left side wall (13) by the protruding ribs for side walls (17) and (18) brazed to each other, the right side wall (14) by the connecting part (28), and the upper wall by the upper wall forming part (26) ( 11), the lower wall 12 is formed by the lower wall forming portion 27, and the reinforcing wall 15 is formed by the reinforcing wall projections 19 and 20 brazed to each other.

  The production of the flat heat exchange tube (4) is performed simultaneously with the production of the heat exchanger (1). That is, the heat exchanger (1) is manufactured as follows. First, a plurality of bent bodies (33) are prepared, a pair of aluminum headers (2) (3) having the same number of bent body insertion holes as the bent bodies (33), and a plurality of aluminum corrugated fins (6 ) And prepare. Next, a pair of headers (2) and (3) are arranged at intervals, and a plurality of folded bodies (33) and fins (6) are alternately arranged, and both ends of the folded body (33) are attached to the header. (2) Insert into the bent body insertion hole in (3). Thereafter, these are heated to a predetermined temperature, and the ridges (17), (18) for the side walls of the bent body (33) and the ridges for the reinforcing wall (19), (20), the bent body (33) and the header (2 ) (3), and the bent body (33) and the corrugated fin (6) are simultaneously brazed using the brazing material layer of the metal plate (25) for producing a flat heat exchange tube. Thus, the heat exchanger (1) is manufactured. This heat exchanger (1) constitutes a refrigeration cycle that uses a chlorofluorocarbon refrigerant as a condenser, together with a compressor and an evaporator, and is mounted on an automobile as a car air conditioner, for example.

The flat heat exchange pipe (4) includes a compressor, a gas cooler, an evaporator, a decompressor, and an intermediate heat exchanger for exchanging heat between the refrigerant coming out of the gas cooler and the refrigerant coming out of the evaporator, and a refrigeration cycle using a supercritical refrigerant such as CO _2, is sometimes used in the gas cooler and the evaporator. This refrigeration cycle is mounted on a vehicle such as an automobile as a car air conditioner.

  FIG. 4 schematically shows the configuration of the pressure resistance test apparatus for the heat exchanger (1).

  In FIG. 4, the pressure resistance testing apparatus holds the heat exchanger (1) in a holding device (40) (holding means) that holds the heat exchanger (1) in a horizontal state so that the ventilation direction is in the vertical direction, and the holding device (40). A high-pressure air supply device (41) (pressurizing means) that pressurizes the inside of the heat exchanger (1) by supplying high-pressure air into the sealed and sealed heat exchanger (1), and a holding device (40) Illumination (42) (light irradiation means) that irradiates light from below (one side in the ventilation direction) to the held heat exchanger (1) and above the heat exchanger (1) held by the holding device (40) And a reflecting plate (43) (reflecting means) made of a mirror that reflects light from below to the side, in this case to the right, and a CCD camera (44) that captures an image reflected by the reflecting plate (43) ) (Imaging means), an image processing device (45) (processing means), and an operation and display device (46) for performing each operation and displaying a pressure-resistant test result.

  The holding device (40) holds both headers (2) and (3) of the heat exchanger (1) so as not to block the ventilation gap (5).

  The CCD camera (44) captures a reflected image by the reflector (43) of the heat exchanger (1) irradiated with light from below by the illumination (42) as a monochrome image, and the image signal is image processed. Output to the device (45).

  The image processing device (45) divides the imaging range of the monochrome image captured by the CCD camera (44) into a plurality of dots (pixels), applies gray processing, and sets luminance information at each dot according to a predetermined threshold value. The white portion and the black portion are binarized, and the pattern of the white portion and the black portion in the imaging range is extracted. Here, the pattern of the white part and the black part means, for example, the shape, size, and dispersion state. In addition, the image processing device (45) includes the pattern before the high pressure air is supplied to the inside of the heat exchanger (1) by the high pressure air supply device (41), and the state after the pressure is applied. Compared with the pattern, the pressure resistance of the heat exchanger (1) is determined based on the pattern before pressurization and the continuous change of the pattern after pressurization, and the determination result is displayed on the operation and display device ( Output to 46). The image processing device (45) also displays on the operation / display device (46) the internal pressure when the pattern starts changing after the start of pressurization and the internal pressure when the pattern stops changing. To do. Further, the image processing device (45) stops the supply of high-pressure air into the heat exchanger (1) by the high-pressure air supply device (41) when the pattern after the start of pressurization changes abnormally.

  5 to 9 show a specific configuration of the pressure resistance test apparatus. In the following description of the pressure resistance testing apparatus, the top and bottom of FIG. 5 are referred to as the top and bottom, the left side of FIG. 5 is the front, and the right side is the back. Moreover, let the left and right of FIG. 6 be left and right.

  As shown in FIG. 5, the holding device (40), the high-pressure air supply device (41), the illumination (42), the reflector (43), the CCD camera (44), and the image processing device (45) of the pressure resistance testing device are Arranged in one housing (200), the operation and display device (46) is arranged outside the housing (200). The pressure resistance inspection apparatus is incorporated in the production line of the heat exchanger (1). The housing (200) is provided on the floor of the factory where the production line for the heat exchanger (1) is installed via the seismic isolation device (201).

  A first chamber (202) in which a holding device (40) and an illumination (42) are disposed in a housing (200), and a high pressure air supply device (41) positioned below the first chamber (202) A second chamber (203) in which the first processing chamber (202) is disposed, a third chamber (204) that is located behind the first chamber (202) and in which the image processing device (45) is disposed, A fourth chamber (located above the chambers (202) and (204) so as to straddle the third chambers (202) and (204) and in which the reflector (43) and the CCD camera (44) are disposed ( 205). The housing (200) has a plane structure, and a load applied to the housing (200) is supported by six metal plates constituting a ceiling, a floor, and a peripheral wall of the housing (200), for example, a steel plate having a thickness of 10 mm or more. ing. The first chamber (202), the second chamber (203), and the third chamber (204) communicate with each other through an air hole (230) formed in the partition wall.

  The front wall of the first chamber (202) is formed with a loading / unloading port (206) of the heat exchanger (1) to be inspected, and the loading / unloading port (206) is opened and closed by the elevating door (207). Yes. The first chamber (202) is partitioned into two upper and lower spaces by a partition plate (208) provided in the lower portion of the first chamber (202), and the holding device (40) is placed in the upper space. The lighting (42) is installed in the lower space. The partition plate (208) is formed with an opening (208a) that is larger than the heat exchanger (1) to be inspected and through which light irradiated by the illumination (42) passes. An inspection port (209) for inspecting the illumination (42) is formed at a height position corresponding to the lower space on the front wall of the first chamber (202), and the inspection port (209) is an open door. It is opened and closed by (211).

  On the left side wall of the second chamber (203), a blower (212) that takes outside air into the housing (200) and maintains the inside of the first to third chambers (202), (203), and (204) at a positive pressure. ) (Positive pressure holding means) is attached. Although not shown, the blower (212) is provided with a filter that prevents dust from entering the housing (200).

  The right side wall of the third chamber (204) is provided with an air conditioner (213) that circulates the air in the third chamber (204) and maintains a constant temperature. An inspection port (214) for inspecting the image processing device (45) is formed in the rear wall of the third chamber (204), and the inspection port (214) is opened and closed by an opening door (215). It has become.

  The fourth chamber (205) is in a sealed state independent of the other chambers (202) to (204). The right side wall of the fourth chamber (205) is provided with an air conditioner (216) that circulates the air in the fourth chamber (205) and maintains a constant temperature. Further, the front portion of the partition wall (217) that partitions the fourth chamber (205) from the first chamber (202) and the third chamber (204), that is, a portion corresponding to the first chamber (202). An opening (217a) is formed, and the opening (217a) is hermetically closed by a translucent plate (218) made of glass or the like. The opening (217a) is sized so that the entire image of the heat exchanger (1) held by the holding device (40) can be reflected by the reflecting plate (43) toward the CCD camera (44). An inspection port (210) for inspecting the CCD camera (44) is formed in the rear wall of the fourth chamber (205), and the inspection port (210) is opened and closed by an opening door (219). Yes.

  As shown in FIGS. 6 to 8, the holding device (40) is provided on the partition plate (208) and holds the first header (2) of the heat exchanger (1) to be inspected. A device (220) and a second clamp device (221) provided on the partition plate (208) and holding the other header (3) of the heat exchanger (1) to be inspected are provided.

  The first clamping device (220) is movable along the guide (222) extending in the front-rear direction fixed on the left side of the opening (208a) of the partition plate (208) and the guide (222). It consists of two front and rear substrates (223) provided so as to be fixed at an arbitrary position on the guide (222), and a fixing clamp member (224) provided on each substrate (223) so as to project upward. Each substrate (223) is fixed at an arbitrary position on the guide (222), so that the lengths of the headers (2) of the heat exchanger (1) to be inspected are matched with the lengths of both fixing clamp members (224). The position in the front-rear direction is adjusted. Each fixed clamp member (224) has a recess (225) that opens to the right and into which a part of one header (2) of the heat exchanger (1) fits. An anti-slip member (226) made of, for example, rubber is attached to the upper part of the inner peripheral surface.

  The second clamping device (221) moves along a pair of guides (227) extending in the left-right direction fixed to the front and rear side portions of the opening (208a) on the partition plate (208), and each guide (227). And a saddle (228) provided so as to be fixed at an arbitrary position on the guide (227), a rail support plate (229) secured between the front and rear saddles (228), and a rail support plate A rail (231) provided in (229) and extending in the front-rear direction, and a substrate attached to the rail (231) via, for example, a linear guide (not shown) and movable in the front-rear direction along the rail (231) ( 232), a pair of supports (233) provided in a standing manner on the substrate (232) at intervals in the front-rear direction, and a movable clamp member (234) attached to the support (233). The saddle (228) is fixed at any position on the guide (227), so that the horizontal dimension of the heat exchanger (1) to be inspected Together so that the lateral position of the movable clamp member (234) is adjusted. Further, the movable clamp member (234) is movable in the length direction of the header (3) of the heat exchanger (1) by moving the substrate (232) along the rail (231).

  The movable clamp member (234) includes a base portion (235) that is long in the front-rear direction, and a pair of clamp portions (236) that are provided on the base portion (235) at intervals in the front-rear direction. A bracket (237) protruding rightward is provided at the center of the base (235) in the length direction. Each clamp part (236) has a recess (238) that opens to the left while holding the heat exchanger (1) and into which a part of the other header (3) of the heat exchanger (1) fits. is doing.

  The movable clamp member (234) is attached to both supports (233) via a pair of front and rear arms (239). A shaft (241) extending in the front-rear direction so as to penetrate both arms (239) is fixed, and a portion of the shaft (241) protruding outward from the both arms (239) in the front-rear direction is the same height in both supports (233). A long hole (242) that is formed in the right and left direction and that is long in the left and right direction is fitted so as to be rotatable and movable in the left and right direction. A support plate (243) is secured between the left end portions of both arms (239), and the right end portion of the bracket (237) of the movable clamp member (234) is placed on the support plate (243), and extends vertically. (244) is rotatably mounted about the axis of the pin (244). The movable clamp member (234) is disposed between a spring mounting plate (245) fixed between the right ends of both supports (233) and both arms (239) and is rotatable around a shaft (241). The compression coil spring (247) (biasing means) mounted between the covered spring receiver (246) is always urged to the left, that is, to the fixed clamp member (224) side with respect to the support (233). ing. The left end of the spring (247) is received by the spring receiver (246). A cylindrical spring holding member (248) is fixed to the left side surface of the spring mounting plate (245), and a spring receiver (249) is arranged in the spring holding member (248) so as to be movable in the left-right direction. ) Is placed in a spring holding member (248) and received by a spring receiver (249). The spring receiver (249) is formed through the spring mounting plate (245) so that it is pressed to the left by the external screw (252) screwed into the screw hole (251) from the right. This adjusts the urging force of the spring (247).

  Then, both the arms (239) rotate integrally with the shaft (241) and move integrally with the shaft (241) and support (233) in the left-right direction, whereby the movable clamp member (234) Between the holding position for holding the heat exchanger (1) in a horizontal state together with the fixed clamp member (224) (see the solid line in FIG. 6) and the release position for releasing the heat exchanger (1) (see the chain line in FIG. 6). It is supposed to move. When the movable clamp member (234) is in the holding position, the pin (244) is in a vertical state, and as a result, the movable clamp member (234) is rotatable about the vertical axis. Further, when the movable clamp member (234) is in the release position, the recess (238) of the clamp portion (236) opens obliquely upward. When the movable clamp member (234) is in the holding position between the arms (239) and the supports (233), both arms (239) are urged counterclockwise in FIG. A tension coil spring (253) (biasing means) is mounted which can bias both arms (239) clockwise in FIG. 6 when 234) is in the release position.

  The high-pressure air supply device (41) includes a high-pressure air supply hose (not shown) having a connector connected to the inlet pipe (7) or the outlet pipe (8) of the heat exchanger (1) at the tip. The high pressure air supply hose extends into the first chamber (202) through a partition wall separating the first chamber (202) and the second chamber (203).

  The illumination (42) includes a casing (260) opened upward, a plurality of fluorescent lamps (261) (light source) disposed in the casing (260), and an upper end opening of the casing (260) closed, and a fluorescent lamp A light diffusing plate (262) for uniformly diffusing the light emitted from the lamp (261) to form surface illumination, and the fluorescent lamp (261) disposed below the fluorescent lamp (261) in the casing (260) And a reflector (263) that reflects upward light and makes upward light strong (see FIG. 6). Note that the number of fluorescent lamps (261) is preferably small in consideration of cost, calorific value, and the like. Even if the number of fluorescent lamps (261) is small, it is possible to obtain surface illumination and to obtain strong upward light by the action of the light diffusion plate (262) and the reflection plate (263).

  The reflector (43) is a ventilation gap (5) between adjacent flat heat exchange tubes (4) of the heat exchanger (1) irradiated from the illumination (42) and held by the holding device (40). The light that has passed through is reflected to the CCD camera (44) side. Since the angle of view of the CCD camera (44) is constant, if the corrugated fin (6) is inclined to the header (2) (3) side, the ventilation gap (5) between the heat exchange tubes (4) The light that has passed through the portion close to the headers (2) and (3) in () cannot be reflected toward the CCD camera (44) by the reflector (43). In order to prevent this, auxiliary reflectors (254) are arranged on both the left and right sides of the reflector (43) in the fourth chamber (205) (see FIG. 9). A plurality of CCD cameras (44) are arranged vertically and horizontally.

  Next, a pressure resistance inspection method for the heat exchanger (1) using the pressure resistance inspection apparatus described above will be described.

  First, the elevating door (207) is raised to open the loading / unloading port (206). At this time, the movable clamp member (234) of the holding device (40) is in the release position. Next, one header (2) of the heat exchanger (1) is fitted into the recess (225) of the fixed clamp member (224) in the first clamp device (220) of the holding device (40). Further, the other header (3) of the heat exchanger (1) is fitted into the recess (238) of the movable clamp member (234) in the second clamp device (221). Next, the movable clamp member (234) is pushed down and moved to the holding position. At this time, the heat exchanger (1) is firmly fixed by the clamp members (224) and (234) by the biasing force of the compression coil spring (247). Next, either one of the inlet pipe (7) and the outlet pipe (8) is sealed, and a connector at the tip of the high-pressure air supply hose in the high-pressure air supply device (41) is connected to the other. Next, the elevator door (207) is lowered to close the loading / unloading port (206), and the pressure resistance test is started by the operation and display device (46).

  In other words, the illumination (42) irradiates light to the heat exchanger (1) from below, and the CCD camera (44) captures a reflection image by the reflector (43) as a monochrome image. The image signal obtained by the CCD camera (44) is output to the image processing device (45). The image processing device (45) divides the imaging range of the monochrome image captured by the CCD camera (44) into a plurality of dots (pixels), applies gray processing, and sets luminance information at each dot according to a predetermined threshold value. The binarization is performed on the white portion and the black portion, and the pattern of the white portion and the black portion in the imaging range is extracted and stored.

  Next, high-pressure air is supplied into the heat exchanger (1) by the high-pressure air supply device (41) to pressurize the inside of the heat exchanger (1) to a set value. The pattern of the white part and the black part in the imaging range is continuously extracted.

  If the brazing part between the projections (19) and (20) for the reinforcing wall of the flat heat exchange pipe (4) is defective, or the brazing strength of the brazing part is insufficient In this case, when the inside of the heat exchanger (1) is pressurized, as shown in FIGS. 10 and 11, the internal joints between the tips of the reinforcing wall projections (19) and (20) are broken and both ends are broken. A relatively large gap is formed between the ridges (19) and (20), and the flat heat exchange pipe (4) is deformed so as to swell greatly and the corrugated fin (6) disposed in the ventilation gap (5) is deformed. To do. Therefore, the amount of light transmitted through the ventilation gap (5) is reduced, and the pattern of the white part and the black part in the imaging range extracted by the image processing device (45) It changes significantly compared to the pattern. In this case, the image processing device (45) compares the pattern after pressurization with the pattern before pressurization, and if the change amount of the pattern after pressurization is equal to or greater than a predetermined threshold value, Is determined as a defective product, and the determination result is displayed on the operation and display device (46).

  Contrary to this, no brazing defects occurred in the brazed portions of the reinforcing wall projections (19) and (20) of the flat heat exchange pipe (4), and the brazed portions were brazed. When the strength is sufficiently large, no breakage occurs at the internal joints between the tips of the reinforcing wall projections (19) and (20). However, in this case as well, when the inside of the heat exchanger (1) is pressurized, the flat heat exchange tubes (4) and the corrugated fins (6) are slightly deformed, and the deformation ends at a certain degree. In this case, the image processing device (45) detects the start and end of such deformation based on the amount of change in the pattern after pressurization, and displays the deformation start pressure and the deformation end pressure as the operation and display device (46). Output to.

  When only the deformation of the flat heat exchange pipe (4) and corrugated fin (6) without breakage of the internal joints between the ends of the reinforcing wall projections (19) and (20) as described above occurs The pattern after pressing hardly changes compared to the pattern before pressing. In this case, the image processing device (45) determines that the product is excellent in pressure resistance, and displays the determination result on the operation / display device (46).

  When the deformation of the flat heat exchange pipe (4) and the corrugated fin (6) accompanied by the breaking of the internal joints between the ends of the reinforcing wall projections (19) (20) as described above, In any case where deformation of the flat heat exchange tube (4) and corrugated fin (6) without breakage of the joint occurs, the heat exchanger (1) is deformed as a whole and warps or flickers light. As a result, the pattern after pressurization may change. However, when deformation of the flat heat exchange pipe (4) and corrugated fin (6) accompanied by the fracture of the internal joint occurs, and the flat heat exchange pipe (4) and the corrugated fin (6) without fracture of the internal joint. Since the change in the pattern differs between when the corrugated fin (6) is deformed and when the entire heat exchanger (1) is deformed and warps or light flickers, the image processing apparatus (45) is a deformation of the flat heat exchange tube (4) and corrugated fin (6) based on the continuous change of the pattern before pressurization and the pattern after pressurization, or the heat exchanger (1) Determine the overall deformation and warpage or flickering of light.

  When the inside of the heat exchanger (1) is pressurized and the entire heat exchanger (1) is deformed or displaced, the movable clamp member (234) approaches the fixed clamp member (224). In addition to being spaced apart and being biased toward the fixed clamp member (224) by the compression coil spring (247), deformation, deterioration, wear, etc. of the clamp members (224) and (234) can be suppressed. Moreover, in addition to the approach and separation of the movable clamp member (234) from the fixed clamp member (224), the movable clamp member (234) in the holding position is rotatable around the vertical axis, and the movable clamp member ( 234) is movable in the length direction of the header (3) of the heat exchanger (1), the deviation of the heat exchanger (1) from the inspection reference position can be suppressed.

  If the brazing part of the ribs (19) and (20) of the reinforcing wall of the flat heat exchange pipe (4) is brazed, or if the brazing strength of the brazed part is extremely insufficient In such a case, the heat exchange pipe (4) may be destroyed in a burst before the internal pressure of the heat exchanger (1) reaches a set value. When the pattern after pressurization changes abnormally, the image processing device (45) stops the supply of high-pressure air into the heat exchanger (1) by the high-pressure air supply device (41). Also, in this case, it is possible to assume the breaking pressure from the correlation between the continuous change when the pattern after pressure changes abnormally and the internal pressure, and it is possible to know the breaking pressure. Become.

  In the pressure resistance inspection method described above, the pattern extraction of the white part and the black part in the imaging range after the start of pressurization by the image processing device (45) may be performed intermittently.

  Next, another example of the pressure resistance test method for the heat exchanger (1) using the pressure resistance test apparatus described above will be described.

  First, in the same manner as described above, the heat exchanger (1) is held by the holding device (40), and either the inlet pipe (7) or the outlet pipe (8) is sealed and the other is pressurized. A connector at the tip of the high pressure air supply hose in the air supply device (41) is connected. Next, the elevating door (207) is lowered to close the loading / unloading port (206).

  Then, the illumination (42) irradiates the heat exchanger (1) with light from below, and the CCD camera (44) captures a reflection image by the reflector (43) as a monochrome image. The image signal obtained by the CCD camera (44) is output to the image processing device (45). The image processing device (45) divides the imaging range of the monochrome image captured by the CCD camera (44) into a plurality of dots (pixels), applies gray processing, and sets luminance information at each dot according to a predetermined threshold value. It binarizes the white part and the black part, counts the number of black parts, and stores the number of black parts in the imaging range. In the heat exchanger (1) before pressurizing the interior, a lot of light is transmitted through the ventilation gap (5) between adjacent flat heat exchange tubes (4), so the number of black portions is reduced. ing. In addition, each dot of the part corresponding to the flat heat exchange tube (4) in the imaging range is a black part.

  Next, high pressure air is supplied into the heat exchanger (1) by the high pressure air supply device (41) to pressurize the inside of the heat exchanger (1), and the number of black portions in the imaging range is determined in the same manner as described above. Count continuously and store the number of black parts.

  If the brazing part between the projections (19) and (20) for the reinforcing wall of the flat heat exchange pipe (4) is defective, or the brazing strength of the brazing part is insufficient In this case, when the inside of the heat exchanger (1) is pressurized, the flat heat exchange pipe (4) and the corrugated fin (6) are deformed as shown in FIGS. Accordingly, the amount of light transmitted through the ventilation gap (5) is reduced, and the number of black portions counted by the image processing device (45) is significantly increased compared to the number of black portions before pressurization. In this case, the image processing device (45) compares the number of black portions after pressurization with the number of black portions before pressurization, and the increase in the number of black portions after pressurization is equal to or greater than a predetermined threshold value. Is determined to be a defective product with insufficient pressure resistance, and the determination result is displayed on the operation and display device (46).

  Contrary to this, no brazing defects occurred in the brazed portions of the reinforcing wall projections (19) and (20) of the flat heat exchange pipe (4), and the brazed portions were brazed. When the strength is sufficiently large, no breakage occurs at the internal joints between the tips of the reinforcing wall projections (19) and (20). However, in this case as well, when the inside of the heat exchanger (1) is pressurized, the flat heat exchange tubes (4) and the corrugated fins (6) are slightly deformed, and the deformation ends at a certain degree. In this case, the image processing device (45) detects the start and end of such deformation based on the increase in the number of black portions after pressurization, and displays the deformation start pressure and the deformation end pressure as an operation and display device ( Output to 46).

  When only the deformation of the flat heat exchange pipe (4) and corrugated fin (6) without breakage of the internal joints between the ends of the reinforcing wall projections (19) and (20) as described above occurs The amount of light transmitted through the ventilation gap (5) hardly decreases even before pressurization. Therefore, the number of black portions counted by the image processing device (45) hardly increases compared to the number of black portions before pressurization, and the increase in black portions after pressurization is a predetermined threshold value. Less than. In this case, the image processing device (45) determines that the product is excellent in pressure resistance, and displays the determination result of the operation / display device (46).

  Note that when the inside of the heat exchanger (1) is pressurized, the function of the holding device (40) when the entire heat exchanger (1) is deformed or displaced is the same as in the above-described method. .

  Next, in the other pressure resistance test methods described above, the relationship between the internal pressure and the continuous change in the number of black portions in the heat exchanger (1) in various states will be described with reference to FIG.

  Fig. 12 (a) shows a case where no brazing failure occurs between the reinforcing wall projections (19) and (20) between all the reinforcing walls (15) of the flat heat exchange pipe (4). Show. In this case, the change in the number of black portions is within a predetermined range (A), and the increase number (change number) of the black portions is less than a predetermined threshold value.

  FIG. 12 (b) shows that a defective brazing occurs between a small number of all the reinforcing walls (15), for example, between the reinforcing wall projections (19) and (20) of one reinforcing wall (15). In the remaining reinforcing wall (15), if there is no defective brazing between the reinforcing wall ridges (19), (20), or between the reinforcing wall ridges (19), (20), At least two reinforcing walls (15) sandwiching a plurality of reinforcing walls (15) between which brazing defects have not occurred are caused by brazing defects between the reinforcing wall projections (19) and (20). Indicates the case. In this case, since the pressure resistance is not significantly reduced, the flat heat exchange tubes (4) and corrugated fins (6) are deformed at a relatively high internal pressure, and the number of black portions increases rapidly. Exceeds the threshold value and is determined to be a defective product. It should be noted that the convexity for the reinforcing wall in at least two reinforcing walls (15) sandwiching the plurality of reinforcing walls (15) between which the reinforcing ribs for reinforcing walls (19) and (20) do not cause poor brazing. If there is a brazing defect between the strips (19) and (20), the reinforcing wall (15) between the two reinforcing walls (15) where the brazing defect has occurred The brazed portions between the ridges (19) and (20) may be broken, and as shown by the chain line X in FIG.

  FIG. 12 (c) shows a case where a defective brazing has occurred between the reinforcing wall projections (19) and (20) in many reinforcing walls (15). In this case, since the pressure resistance is significantly reduced as compared with the case of FIG. 12 (b), the flat heat exchange pipe (4) and the corrugated fin (6) are formed at a lower internal pressure than in the case of FIG. 12 (b). It is greatly deformed, and the number of black parts is remarkably increased. Therefore, the number of increase in the black portion is equal to or greater than the threshold value in a shorter time than in the case of FIG. In this case, the number of black portions is the same as that indicated by the chain line X in FIG.

  In FIG. 12 (d), the reinforcing wall projections (19) and (20) are brazed to each other in all the reinforcing walls (15), but the brazing strength is insufficient due to defective flux application at the time of brazing. Indicates the case. In this case, even if the internal pressing force is higher than in the case of FIG. 12 (c), the number of black portions does not exceed the threshold value. However, when the predetermined internal pressing force is reached, many reinforcing walls (15) In this case, the brazed portions of the reinforcing wall ridges (19) and (20) are destroyed, the flat heat exchange pipe (4) and the corrugated fin (6) are greatly deformed, and the number of black portions increases rapidly. The increase number is equal to or greater than the threshold value, and is determined to be a defective product. In this case, since the degree of deformation of the flat heat exchange pipe (4) and the corrugated fin (6) is large, the position of the flat heat exchange pipe (4) is shifted, and the flat heat exchange pipe (4 ) In the portion corresponding to the black portion may become a white portion, and the number of black portions may decrease as indicated by the curve Y in FIG.

  FIG. 12 (e) shows that no brazing failure occurs between the reinforcing wall projections (19) and (20) in all the reinforcing walls (15) of the flat heat exchange pipe (4). The case where the exchanger (1) is manufactured by applying an excessive force to the deformed header (2) (3), the flat heat exchange pipe (4) and the corrugated fin (6) is shown. In this case, if the internal pressure increases, the heat exchanger (1) as a whole is deformed at a relatively low pressure, the number of black parts increases, and the number of black parts increases above the threshold value. Is done. In this case, since the degree of deformation of the flat heat exchange tube (4) and the corrugated fin (6) is large, the position of the flat heat exchange (4) shifts, and the flat heat exchange tube (4) in the imaging range The dot corresponding to the black portion may become a white portion, and the number of black portions may decrease as indicated by the curve Z in FIG.

  Then, based on the relationship between the internal pressure and the continuous change in the number of black portions shown in FIGS. 12 (a) to (e), the type of defect in the heat exchanger (1) can be known, It is possible to take measures to eliminate it.

  In the other pressure resistance inspection methods described above, the number of black portions after the start of pressurization by the image processing device (45) may be intermittently performed.

  In the above embodiment, the reflection plate (43) as the reflection means is disposed above the heat exchanger (1) held by the holding device (40), and on the side of the reflection plate (43), the reflection plate ( A CCD camera (44) as an imaging means for capturing a reflection image by 43) is arranged, but instead of this, the reflection plate (43) is removed and the heat exchanger (40) held by the holding device (40) ( A CCD camera (44) as an imaging means for directly imaging the heat exchanger (1) may be disposed above 1).

  In the above-described embodiment, the CCD camera (44) is used as the image pickup means. However, the present invention is not limited to this. For example, a line sensor may be used. In this case, in order to capture the entire reflection image of the heat exchanger (1) by the reflector, a moving means for moving the line sensor and the heat exchanger (1) relatively is provided. Further, instead of the CCD camera (44), the light receiving element of the transmission sensor may be used as the image pickup means. In this case, the light projecting element of the transmission sensor becomes the light irradiation means. When the transmission sensor is used, the transmission sensor and the heat exchanger (1) are relatively moved in order to capture the entire reflection image of the heat exchanger (1) by the reflection plate.

  Further, in the above embodiment, the holding means includes the first clamp device (220) having the fixed clamp member (224) and the second clamp device (221) having the movable clamp member (234). However, instead of this, a first clamping device having a movable clamping member for holding one header (2) of the heat exchanger (1) and a first clamping device are spaced apart from each other. And a second clamping device having a movable clamping member that holds the other header (3) of the heat exchanger (1), and the movable clamping member of each clamping device The movable clamp member is movable toward and away from the movable clamp member, and is biased toward the movable clamp member side of the other clamp device by the biasing means, and the total number of the first clamp device and the second clamp device is Even with devices that are 3 or more There. In this case, the movable clamp member of each clamp device can rotate around the vertical axis while holding the heat exchanger (1), and the length of the header (2) (3) of the heat exchanger (1). It becomes movable in the direction.

  The pressure resistance test of the heat exchanger (1) can also be performed by the following method.

  That is, the inside of the heat exchanger (1) is pressurized, and during pressurization, light is continuously or intermittently irradiated from one side of the heat exchanger (1) and from the opposite side of the heat exchanger (1). This is a method performed by visual observation.

  In this method, the deformation of the corrugated fin (6) of the heat exchanger (1) and / or the deformation of the heat exchange pipe (4) of the heat exchanger (1) is visually observed.

  Note that the refrigerant circulation part of the heat exchanger whose pressure resistance is inspected by the method according to the present invention is not limited to the flat heat exchange pipe shown in FIG. 2, and the hollow refrigerant circulation part having an internal joint part is arranged in parallel. As long as the heat exchanger is provided, the pressure resistance can be inspected regardless of the form of the refrigerant circulation section.

It is a perspective view which shows one example of the heat exchanger by which pressure resistance is test | inspected with the method and apparatus of this invention. FIG. 2 is an enlarged cross-sectional view showing a flat heat exchange tube of the heat exchanger of FIG. 1. It is a figure which shows the method of manufacturing the flat heat exchange pipe | tube of FIG. It is a figure which shows schematic structure of the pressure | voltage resistant test | inspection apparatus of the heat exchanger by this invention. It is the vertical sectional view seen from the right side which shows the concrete composition of the pressure resistance inspection device of the heat exchanger by this invention. FIG. 6 is an enlarged sectional view taken along line VI-VI in FIG. 5. It is the VII-VII sectional view taken on the line of FIG. It is the VIII-VIII line expanded sectional view of FIG. It is the IX-IX sectional view taken on the line of FIG. It is a front view equivalent to a part of Drawing 1 showing the state where the internal joined part of a flat heat exchange pipe was destroyed by pressurization inside a heat exchanger. It is the XI-XI line expanded sectional view of FIG. It is a graph which shows the relationship between the internal pressure in the heat exchanger of various states, and the continuous change of the number of black parts.

(1): Heat exchanger
(4): Flat heat exchange pipe (refrigerant circulation part)
(5): Ventilation gap
(6): Corrugated fin
(40): Holding device (holding means)
(41): High-pressure air supply device (pressurizing means)
(42): Illumination (light irradiation means)
(43): Reflector (reflecting means)
(44): CCD camera (imaging means)
(45): Image processing device (processing means)

Claims (17)

A heat exchanger in which a plurality of hollow refrigerant circulation portions having internal joints are provided in parallel, and a ventilation gap is provided between adjacent refrigerant circulation portions, and fins are disposed in the ventilation gap. A method for inspecting the pressure resistance of
The heat exchanger is irradiated with light from one side of the ventilation direction, the heat exchanger is imaged by the imaging means from the opposite side of the ventilation direction, the imaging range is divided into a plurality of dots, and based on the luminance information at each dot Obtain the brightness information of the imaging range, then pressurize the inside of the heat exchanger, and after starting the pressurization, continuously image the heat exchanger from the opposite side of the ventilation direction with the imaging means and divide the imaging range into multiple dots In addition, the luminance information of the imaging range is obtained based on the luminance information in each dot, and the heat exchanger of the heat exchanger is determined based on the continuous change in the luminance information of the imaging range before pressurization and the luminance information of the imaging range after pressurization. A pressure resistance inspection method for a heat exchanger, characterized by determining pressure resistance. The pressure resistance test method for a heat exchanger according to claim 1, wherein the pressure inside the heat exchanger is controlled based on a continuous change in luminance information of the imaging range after pressurization . A monochrome image is obtained by imaging the heat exchanger by the imaging means, the monochrome image is subjected to gray processing, and luminance information at each dot is binarized into a white portion and a black portion by a predetermined threshold value, and a black portion The pressure resistance of the heat exchanger is determined based on a continuous change in the number of black portions before pressurization and the number of black portions after pressurization in the imaging range. Pressure resistance inspection method for heat exchangers. A monochrome image is obtained by imaging the heat exchanger by the imaging means, the monochrome image is subjected to gray processing, and luminance information at each dot is binarized into a white portion and a black portion by a predetermined threshold value, and an imaging range is obtained. The pattern of the white part and black part in is extracted, and the pressure resistance of a heat exchanger is determined based on the continuous change of the pattern before pressurization, and the pattern after pressurization The pressure resistance test method of the heat exchanger as described in 2 . A heat exchanger in which a plurality of hollow refrigerant circulation portions having internal joints are provided in parallel, and a ventilation gap is provided between adjacent refrigerant circulation portions, and fins are disposed in the ventilation gap. A method for inspecting the pressure resistance of
The heat exchanger is irradiated with light from one side of the ventilation direction, the heat exchanger is imaged by the imaging means from the opposite side of the ventilation direction, the imaging range is divided into a plurality of dots, and based on the luminance information at each dot To obtain brightness information of the imaging range, then pressurize the inside of the heat exchanger, and after the start of pressurization, intermittently capture the heat exchanger with the imaging means from the opposite side of the ventilation direction and divide the imaging range into multiple dots In addition, the luminance information of the imaging range is obtained based on the luminance information at each dot, and the heat exchanger's luminance information of the imaging range before pressurization and the intermittent change of the luminance information of the imaging range after pressurization A pressure resistance inspection method for a heat exchanger, characterized by determining pressure resistance. The pressure resistance test method for a heat exchanger according to claim 5, wherein the pressure inside the heat exchanger is controlled based on an intermittent change in luminance information of the imaging range after pressurization . A monochrome image is obtained by imaging the heat exchanger by the imaging means, the monochrome image is subjected to gray processing, and luminance information at each dot is binarized into a white portion and a black portion by a predetermined threshold value, and a black portion 7. The pressure resistance of the heat exchanger is determined based on intermittent change in the number of black portions before pressurization and the number of black portions after pressurization in the imaging range. Pressure resistance inspection method for heat exchangers. A monochrome image is obtained by imaging the heat exchanger by the imaging means, the monochrome image is subjected to gray processing, and luminance information at each dot is binarized into a white portion and a black portion by a predetermined threshold value, and an imaging range is obtained. The pattern of the white part in black and black part is extracted, and the pressure resistance of a heat exchanger is determined based on the pattern before pressurization, and the intermittent change of the pattern after pressurization The pressure resistance test method of the heat exchanger as described in 2 . A plurality of hollow refrigerant circulation portions having internal joints are provided in parallel between a pair of headers spaced from each other, and a ventilation gap is provided between adjacent refrigerant circulation portions. A device for inspecting the pressure resistance of a heat exchanger in which fins are arranged in the ventilation gap,
Imaging the heat exchanger from the pressurizing means that pressurizes the inside of the heat exchanger, the light irradiating means that is disposed on one side of the heat exchanger in the ventilation direction and that irradiates light to the heat exchanger, and the opposite side of the light irradiating means Before and after pressurization by the pressurizing unit, the imaging range by the imaging unit is divided into a plurality of dots, and luminance information of the imaging range is obtained based on the luminance information of each dot, and the luminance of the imaging range Processing means for determining the pressure resistance of the heat exchanger based on information, and the processing means continuously or intermittently changes the luminance information of the imaging range before pressurization and the luminance information of the imaging range after pressurization. Pressure resistance inspection device for heat exchanger that determines the pressure resistance of the heat exchanger based on the above . The pressure resistance of the heat exchanger according to claim 9, wherein the processing means controls the pressure inside the heat exchanger by the pressurizing means based on a continuous change or intermittent change in luminance information of the imaging range after pressurization. Inspection device . The processing means performs gray processing on the monochrome image obtained by imaging the heat exchanger by the imaging means, binarizes the luminance information at each dot into a white portion and a black portion by a predetermined threshold, and black The number of parts is counted, and the pressure resistance of the heat exchanger is determined based on a continuous change or intermittent change in the number of black parts before pressurization and the number of black parts after pressurization in the imaging range. Or the pressure resistance test | inspection apparatus of the heat exchanger of 10 . The processing means applies a gray process to the monochrome image obtained by imaging the heat exchanger by the imaging means, and binarizes the luminance information at each dot into a white portion and a black portion with a predetermined threshold, The pattern of the white part and the black part in the range is extracted, and the pressure resistance of the heat exchanger is determined based on the continuous change or intermittent change of the pattern before pressurization and the pattern after pressurization. The pressure-resistant test | inspection apparatus of the heat exchanger in any one of them . The pressure tester for a heat exchanger according to any one of claims 9 to 12, wherein the pressurizing means comprises a high-pressure air supply device for supplying high-pressure air into the heat exchanger. The pressure resistance inspection apparatus for a heat exchanger according to any one of claims 9 to 13, wherein the imaging means comprises a CCD camera . The heat exchanger pressure resistance inspection apparatus according to any one of claims 9 to 13 , wherein the imaging means includes a line sensor, and includes moving means for relatively moving the line sensor and the heat exchanger . The pressure resistance inspection apparatus for a heat exchanger according to any one of claims 9 to 15 , wherein the processing means comprises an image processing apparatus. The heat exchanger manufacturing line provided with the pressure | voltage resistant test | inspection apparatus in any one of Claims 9-16 .

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