JP6878693B2 - Heat transfer tube inspection device, heat transfer tube inspection method and program - Google Patents

Description

The present invention relates to a heat transfer tube inspection device, a heat transfer tube inspection method and a program.

Some heat transfer tube inspection devices inspect the heat transfer tube for deformation based on the external shape of the cylindrical heat transfer tube. For example, Patent Document 1 discloses a heat transfer tube inspection device that inspects the presence or absence of deformation of a plurality of cylindrical heat transfer tubes extending linearly in the horizontal direction.

The inspection device described in Patent Document 1 has a roller that rotates on a heat transfer tube, a device body that moves along the heat transfer tube by rotating the roller, and is suspended from the device body between the heat transfer tube and the heat transfer tube. It is equipped with a camera that captures the appearance of the heat transfer tube. The inspection device described in Patent Document 1 inspects the presence or absence of wall thinning on the surface of the heat transfer tube by comparing the external image of the heat transfer tube captured by the camera with the external image of the normal heat transfer tube recorded in the storage unit. ..

Japanese Unexamined Patent Publication No. 10-197219

Since the inspection device described in Patent Document 1 is moved by a roller that rotates on a heat transfer tube extending in the horizontal direction, it is difficult for the heat transfer tube having a bent portion to move along the heat transfer tube. Therefore, it is difficult for the inspection device described in Patent Document 1 to inspect the presence or absence of deformation of the pipe having the bent portion.

Further, the inspection device described in Patent Document 1 compares the external image of a normal heat transfer tube with the external image of the imaged heat transfer tube to inspect the presence or absence of wall thinning. Therefore, if the heat transfer tube is bent, the inspection device may be used. It is necessary to store the appearance image of the normal bending in the storage unit for each bending shape. As a result, it is difficult for the inspection device described in Patent Document 1 to inspect whether or not the bent shape is deformed from the normal shape.

The present invention has been made to solve the above problems, and is a heat transfer tube inspection device, a heat transfer tube inspection method, and a heat transfer tube inspection device capable of easily inspecting the shape of a bent portion of a U-shaped bent heat transfer tube. The purpose is to provide a program.

In order to achieve the above object, the heat transfer tube inspection device according to the present invention includes a detection unit and a determination unit. The detection unit irradiates the bent portion of the U-shaped bent cylindrical heat transfer tube with light, and a plurality of detection portions on the outer periphery of the cross section are located at a plurality of locations of the bent portion, including the top, in the direction in which the heat transfer tube is bent. detecting the respective parts of the position. Determination unit detecting unit detects the respective plurality of locations, and setting a circle having an arc that approximates a plurality of parts each correspond to positions on the periphery of the cross-section, of the arc approximated by respective plurality of locations, the bent portions of the If there is an arc larger than the arc at the top, it is determined that the heat transfer tube is defective.

According to the configuration of the present invention, the determination unit sets a circle having an arc that approximates the position of a part of the outer circumference of the cross section detected by the detection unit, and is based on the correspondence between the positions of the plurality of locations and the size of the circle. To judge the quality of the heat transfer tube. Therefore, in the heat transfer tube inspection device, it is not necessary to store the external image of the heat transfer tube in advance, and it is not necessary to compare the external image with the outer shape of the heat transfer tube. As a result, the quality of the shape of the bent portion can be easily inspected.

Front view of a heat exchanger which is an object of the heat transfer tube inspection device according to the first embodiment of the present invention. Front view of the heat transfer tube inspection device according to the first embodiment of the present invention. Side view of the heat transfer tube inspection device according to the first embodiment of the present invention. Hardware configuration diagram of the control unit included in the heat transfer tube inspection device according to the first embodiment of the present invention. Conceptual diagram of the outer shape of the cross section detected by the profile sensor included in the heat transfer tube inspection device according to the first embodiment of the present invention. FIG. 5 is a flow chart of a heat transfer tube inspection process of a control unit included in the heat transfer tube inspection device according to the first embodiment of the present invention. Front view of a bent portion which is an object of the heat transfer tube inspection device according to the first embodiment of the present invention. Conceptual diagram of an approximate circle of a bent portion and a heat transfer tube, which are objects of the heat transfer tube inspection device according to the first embodiment of the present invention. Conceptual diagram of a deformed bent portion, a heat transfer tube, and an approximate circle when the bent portion of the heat transfer tube inspection device according to the first embodiment of the present invention is deformed. Conceptual diagram of a bent portion of the tilted heat exchanger and an approximate circle of the heat transfer tube when the heat exchanger, which is the object of the heat transfer tube inspection device according to the first embodiment of the present invention, is tilted. Front view of the heat transfer tube inspection device according to the second embodiment of the present invention. Enlarged front view of the laser displacement sensor and the drive unit of the heat transfer tube inspection device according to the third embodiment of the present invention. Cross-sectional view of the XIII-XIII cross-sectional line shown in FIG. Side view of a modified example of the heat transfer tube inspection device according to the first embodiment of the present invention.

Hereinafter, the heat transfer tube inspection device, the heat transfer tube inspection method, and the program according to the embodiment of the present invention will be described in detail with reference to the drawings. In the figure, the same or equivalent parts are designated by the same reference numerals. The XYZ coordinate system in the figure is the coordinates when the heat transfer tube inspection device is viewed from the front and the left-right direction is the X-axis direction, the depth direction is the Y-axis direction, and the direction orthogonal to the X-axis and the Y-axis is the Z-axis direction. It is a system. Hereinafter, this coordinate system will be referred to and described as appropriate.

(Embodiment 1)
The heat transfer tube inspection device according to the first embodiment inspects whether or not the heat transfer tube of the heat exchanger is deformed beyond the permissible range in the bent portion bent in a U shape. First, the configuration of the heat exchanger 100 including the bent portion 400 of the heat transfer tube 300, which is the object to be inspected, will be described with reference to FIG. Next, the configuration of the heat transfer tube inspection device 1A will be described with reference to FIGS. 2 to 5. Subsequently, the operation of the heat transfer tube inspection device 1A will be described with reference to FIGS. 6-10.

FIG. 1 is a front view of a heat exchanger 100 which is an object of the heat transfer tube inspection device 1A according to the first embodiment of the present invention.

As shown in FIG. 1, the heat exchanger 100 includes a plurality of fins 200 and a plurality of heat transfer tubes 300 into which the fins 200 are fitted.

The fin 200 is made of a plate of aluminum or an aluminum alloy. The plate surface of the fin 200 is oriented parallel to the XY plane. Since the fins 200 and the fins 200 exchange heat with air, they are arranged at a pitch through which air can pass and are parallel to each other. A plurality of heat transfer tubes 300 extending in the Z direction are passed through the fins 200.

Each of the heat transfer tubes 300 is formed of a cylindrical tube made of aluminum or an aluminum alloy. Each of the heat transfer tubes 300 has one end facing the −Z side in order to connect to a header (not shown) provided on the −Z end side of the heat exchanger 100. Each of the heat transfer tubes 300 extends from one end thereof to the + Z side, and then is folded back to the −Z side by bending in an inverted U shape.

Specifically, the header distributes the refrigerant to the heat transfer tube 300 and also aggregates the refrigerant from the heat transfer tube 300. One end of the heat transfer tube 300 is connected to the header. The heat transfer tube 300 extends parallel to the Z axis from one end thereof and is passed through a plurality of fins 200. Then, the heat transfer tube 300 is passed through the fin 200 located on the + Z side most, and then extends further to the + Z side. The heat transfer tube 300 is then bent in a semicircular shape from the X direction to the −Z direction. As a result, the heat transfer tube 300 is formed with a bent portion 400. Then, the heat transfer tube 300 extends to the −Z side in order to be connected to the header again after being bent at the bent portion 400.

The plurality of heat transfer tubes 300 are arranged in the X direction. A bent portion 400 is formed in each of the heat transfer tubes 300. Therefore, a plurality of bent portions 400 are provided in the entire heat exchanger 100. Further, the plurality of bent portions 400 are arranged in the X direction. Since each of the bent portions 400 is formed separately by bending, scratches, strains, and the like may occur on the bent portion 400 during each bending process. The heat transfer tube inspection device 1A according to the first embodiment inspects the shape of each of the bent portions 400 and determines whether or not there are scratches, strains, or the like. Next, the configuration of the heat transfer tube inspection device 1A will be described.

FIG. 2 is a front view of the heat transfer tube inspection device 1A according to the first embodiment. FIG. 3 is a side view of the heat transfer tube inspection device 1A. FIG. 4 is a hardware configuration diagram of the control unit 50 included in the heat transfer tube inspection device 1A. FIG. 5 is a conceptual diagram of the outer shape of the cross section detected by the profile sensor 30 included in the heat transfer tube inspection device 1A. In addition, in FIG. 2 and FIG. 3, in order to facilitate understanding, the configurations of the frame, the column, and the like included in the heat transfer tube inspection device 1A are omitted.

As shown in FIG. 2, the heat transfer tube inspection device 1A includes a mounting portion 10 on which a heat exchanger 100 having a bent portion 400 to be inspected is mounted, and a heat exchanger 100 mounted on the mounting portion 10. The holding unit 20 for holding the heat exchanger 100, the profile sensor 30 for detecting the outer shape of the cross section of the bent portion 400 of the heat exchanger 100, the driving unit 40 for moving the profile sensor 30, the holding unit 20, the profile sensor 30 and the driving unit. It includes a control unit 50 that controls the operation of the unit 40.

The mounting portion 10 has a + Z plane formed parallel to the XY plane. The + Z plane is larger in the X and Y directions than the XY cross section of the heat exchanger 100. As a result, the heat exchanger 100 can be mounted on the mounting portion 10. A holding portion 20 is provided on the + Z side of the mounting portion 10. The heat exchanger 100 is held by the holding unit 20.

The holding portion 20 includes a clamp mechanism for sandwiching the + X side portion and the −X side portion of the heat exchanger 100 mounted on the mounting portion 10. Here, as shown in FIG. 3, the clamp mechanism is a mechanism in which two plate-shaped bodies 21 are arranged on both sides, and the plate-shaped bodies 21 press the heat exchanger 100 to sandwich the heat exchanger 100. Is. The holding portion 20 sandwiches the heat exchanger 100 between the plate-shaped bodies 21 and arranges the heat exchanger 100 at a fixed position. When the holding unit 20 holds the heat exchanger 100, the profile sensor 30 is arranged on the + Z side of the heat exchanger 100.

The profile sensor 30 is a sensor that irradiates an object with a band-shaped laser beam and measures the position and displacement of the object from the reflected light of the object. That is, the profile sensor 30 is a so-called two-dimensional laser displacement meter that detects the position and displacement of the object in the two-dimensional space. The profile sensor 30 has a light emitting unit and a light receiving unit (not shown).

As shown in FIG. 5, the light emitting portion emits the laser beam L toward the object, that is, the bent portion 400 in the −Z direction. The laser light L is a band-shaped light parallel to the Y-axis when projected on the XY plane. On the other hand, the light receiving portion is formed in a band shape parallel to the Y axis, and the laser beam L receives the reflected light reflected by the bent portion 400.

The profile sensor 30 measures the outer shape 410 of the YZ cross section of the bent portion 400 from the reflected light data received by the light receiving portion. Here, since the outer shape 410 of the YZ cross section measured by the profile sensor 30 is obtained from the reflected light from the bent portion 400, it is only the shape of a part of the outer circumference of the bent portion 400 facing the light receiving portion. The profile sensor 30 is moved in the X direction by the drive unit 40 in order to sequentially measure the plurality of bent portions 400 shown in FIG. Since the profile sensor 30 detects the position of a part of the outer periphery of the cross section of the bent portion 400 with the outer shape 410, it is also referred to as a detection portion in the present specification.

Returning to FIG. 2, the drive unit 40 includes a motor 41, a drive shaft 42 that is directed in the X direction and is rotated by the motor 41, and a stage 43 that moves in the X direction by the rotation of the drive shaft 42. There is.

The motor 41 is composed of a servo motor, a stepping motor, and the like. The motor 41 has an output shaft (not shown), and the rotation of the output shaft is controlled by the control unit 50. The output shaft of the motor 41 is connected to the drive shaft 42.

A stage 43 is screwed onto the drive shaft 42. Further, the profile sensor 30 is fixed to the stage 43. When the drive shaft 42 is rotated by the motor 41, the profile sensor 30 moves together with the stage 43. The positions of the stage 43 and the profile sensor 30 are determined by controlling the amount of rotation of the motor 41 by the control unit 50.

As shown in FIG. 4, the heat transfer tube inspection device 1A includes a storage unit 51 including a RAM (Random Access Memory) and a ROM (Read Only Memory), and a CPU (Central Processing Unit) 52. The heat transfer tube inspection program is stored in the storage unit 51. The control unit 50 is realized by the CPU 52 executing the heat transfer tube inspection program stored in the storage unit 51. The control unit 50 starts or releases the holding of the heat exchanger 100 by the holding unit 20 by pressing a start button or a release button (not shown) provided in the heat transfer tube inspection device 1A. Further, after the holding unit 20 holds the heat exchanger 100, the control unit 50 rotates the motor 41 to move the profile sensor 30 to a position based on the detection range stored in the storage unit 51. After that, the control unit 50 rotates the motor 41 by a certain amount to move the profile sensor 30 at a constant pitch within the detection range, outputs a detection signal at a constant pitch, and bends the profile sensor 30. The outer peripheral shape of the YZ cross section of 400 is measured. The control unit 50 acquires the shape data of the measured outer shape 410.

From the acquired shape data of the YZ cross section, the control unit 50 obtains the diameter or radius of the approximate circle 420 that approximates the position coordinates of each external portion constituting the shape data. The control unit 50 determines whether or not the bent portion 400 is deformed beyond the permissible range from the distribution of the diameter or radius of the approximate circle 420 obtained at regular pitch intervals. Since the control unit 50 determines whether or not the bending unit 400 is deformed outside the permissible range, it is also referred to as a determination unit in this specification.

Next, the operation of the heat transfer tube inspection device 1A will be described with reference to FIGS. 6-10. In the following description, it is assumed that the heat exchanger 100 having the above-described configuration is mounted on the mounting portion 10 of the heat transfer tube inspection device 1A with the bent portion 400 facing the + Z side. Then, by pressing the start button (not shown) described above, the heat exchanger 100 is held by the holding unit 20, and the heat transfer tube inspection program is executed. As a result, the flow of the heat transfer tube inspection process shall be started.

FIG. 6 is a flow chart of a heat transfer tube inspection process of the control unit 50 included in the heat transfer tube inspection device 1A according to the first embodiment. FIG. 7 is a front view of the bent portion 400, which is an object of the heat transfer tube inspection device 1A. FIG. 8 is a conceptual diagram of an approximate circle 420 of the bent portion 400 and the heat transfer tube 300, which are the objects of the heat transfer tube inspection device 1A. FIG. 9 is a conceptual diagram of the deformed bent portion 400, the heat transfer tube 300, and the approximate circle 420. FIG. 10 is a conceptual diagram of a bent portion 400 of the inclined heat exchanger 100 and a heat transfer tube 300 approximate circle 420.

When the flow of the heat transfer tube inspection process is started, first, as shown in FIG. 6, the control unit 50 reads out the detection range data, the range number data, and the approximate range data from the storage unit 51 (step S1). Here, as shown in FIG. 7, the detection range data is defined as the detection start position S at a position separated from the center C1 of the designed bent portion 400 by the distance L1 in the −X direction, and the distance from the center C1 in the + X direction. This is coordinate data in a range in which a position separated by L1 is set as a detection end position E. The detection range data is stored in the storage unit 51 in the same number as the number of arrays in the X direction of the bending unit 400, and the control unit 50 reads out all the detection range data. On the other hand, the range number data is numerical data indicating the number of detection ranges described above. The approximate range data is numerical data that defines a part of a curve extracted from the outer shape 410 of the YZ cross section of the bent portion 400, which is used when obtaining the approximate circle 420 described later. It is numerical data that determines the width in the X direction centered on the top of the extracted curve. For example, the approximate range data is numerical data of 3-5 mm when the diameter of the heat transfer tube 300 is 10 mm. The approximate circle 420 is a circle obtained by the least squares method on a part of the curve defined by the approximate range data.

Next, as shown in FIG. 6, the control unit 50 drives the drive unit 40 to the coordinates of the read detection range data, and the profile sensor 30 detects the outer shape 410 of the YZ cross section of the bent portion 400. (Step S2). In this detection, first, the control unit 50 moves the profile sensor 30 to the coordinates of the detection start position S, and the control unit 50 causes the profile sensor 30 to detect the outer shape 410 of the YZ cross section of the bent portion 400 at those coordinates. Subsequently, the control unit 50 causes the profile sensor 30 to detect the outer shape 410 of the bent portion 400 each time the profile sensor 30 is moved in the X direction by a constant pitch. As a result, the control unit 50 receives the shape data of the outer circumference of the bent portions 400 at a plurality of locations within the coordinates of the detection range data. Further, the control unit 50 counts the number of detected ranges for each detection range data. In this specification, this step is also referred to as a detection step or a detection step because the shape of a part of the outer periphery of the cross section is detected.

Next, the control unit 50 calculates the radius or diameter of a circle that approximates the outer shape 410 of the YZ cross section for each pitch from the shape data of the outer circumference of the folded portions 400 at the plurality of income points (step S3). In the calculation of the radius or diameter, as shown in FIG. 8, a curve connecting the YZ coordinates of each part of the cross section is obtained from the detected shape data of the YZ cross section, and the curve is used as the heat transfer tube on the + Z side of the bent portion 400. It is assumed to have a shape of 300. Then, the radius or diameter of the approximate circle 420 that approximates each of the curves is obtained. Here, the radius or diameter of the approximate circle 420 is one of the curves in the approximate range data centered on the top of the curve that protrudes to the + Z side most of the curves that are assumed to have the shape of the heat transfer tube 300 on the + Z side. It is calculated by extracting the part and finding the circle that best fits a part of the extracted curve by the least squares method. As a result, the radius or diameter of the approximate circle 420 is obtained. In this specification, since the approximate circle 420 is set, this step is also referred to as a circle setting step or a circle setting step. Further, the control unit 50 may obtain an approximate arc instead of the approximate circle 420 and obtain the radius of the arc, and the process may be referred to as a circle setting step or a circle setting step.

Next, as shown in FIG. 6, the control unit 50 determines from the obtained radius or diameter distribution of the circle whether or not there is deformation exceeding the allowable range of the bent portion 400 (step S4). Here, the permissible range is a range within a predetermined design standard.

Specifically, the control unit 50 obtains the maximum radius or diameter in the vicinity of the center C1 of the bent portion 400 shown in FIG. 7 from the radius or diameter of the circle calculated for each pitch. Then, the control unit 50 sets the maximum radius or diameter thereof as the maximum radius or maximum diameter. Subsequently, the control unit 50 reads out the numerical data of the permissible value for determining the permissible range from the storage unit 51. Then, in the control unit 50, the radius or diameter of the approximate circle 420 is equal to or greater than the maximum radius or the maximum diameter at the position of the X coordinate on the −X side of the X coordinate of the position corresponding to the maximum radius or the maximum diameter. Determine if it can grow in size. Further, the control unit 50 may have a radius or diameter of the approximate circle 420 larger than the maximum radius or maximum diameter at the position of the X coordinate on the + X side of the X coordinate of the position corresponding to the maximum radius or maximum diameter. Judge whether or not. When the control unit 50 determines that there is a radius or diameter of the approximate circle 420 that is larger than the maximum radius or maximum diameter by an allowable value or more, the control unit 50 determines that there is deformation exceeding the allowable range. Further, when it is determined that there is no radius or diameter of the approximate circle 420 larger than the maximum radius or the maximum diameter by an allowable value or more, it is determined that there is only deformation within the allowable range or no deformation. As a result, the control unit 50 determines whether the shape of the bent portion 400 is good or bad. In this specification, this step is referred to as a determination step or a determination step.

The reason why the control unit 50 determines the presence or absence of the radius or diameter of the approximate circle 420 which is larger than the maximum radius or the maximum diameter near the center C2 and is larger than the allowable value, and determines whether the shape of the bent portion 400 is good or bad is as follows. Because it depends. That is, when the heat transfer tube 300 is properly bent in an inverted U shape, as shown in FIG. 8, the radius or diameter of the approximate circle 420 at the top T1 of the bent portion 400 is the largest, and the bent portion 400 has the largest radius or diameter. The radius or diameter of the approximate circle 420 gradually decreases as it deviates from the top T1. However, when the heat transfer tube 300 is deformed and is not properly bent in an inverted U shape, as shown in FIG. 9, the deformed portion is larger than the radius or diameter of the approximate circle 420 at the top T2 of the bent portion 400. The radius or diameter of the approximate circle 420 at D1 may be large. Therefore, as described above, the control unit 50 determines the quality of the shape of the bent portion 400 based on the presence or absence of the radius or diameter of the approximate circle 420 larger than the maximum radius or the maximum diameter in the vicinity of the center C2.

Next, as shown in FIG. 6, the control unit 50 determines whether or not there is deformation exceeding the permissible range, and then determines whether or not the processing of all the detection ranges is completed (step S5). In this determination, it is determined whether or not the same number of detection ranges as the number of ranges read from the storage unit 51 is detected, that is, whether or not the number of ranges and the number of ranges counted in step S2 are the same. When the control unit 50 determines that the number of counted ranges is the same (Yes in step S5), the control unit 50 determines that the process is completed and ends the flow of the heat transfer tube inspection process. On the other hand, when the control unit 50 determines that the number of counted ranges is not the same (No in step S5), it determines that the processing is not completed and the unprocessed portion remains, and returns to step S2.

In the heat transfer tube inspection device 1A, as shown in FIG. 10, the fins 200 of the heat exchanger 100 mounted on the mounting portion 10 are tilted in the Z direction due to variations in assembly accuracy and variations during mounting. May be good. Even when the fin 200 is tilted in the Z direction and the bent portion 400 and the bent portion 400 are misaligned in the Z direction, there is no difference from the case where the detected outer shape 410 of the YZ cross section is not misaligned. As a result, the radius or diameter of the approximate circle 420 obtained by the control unit 50 is the same as the radius or diameter of the approximate circle 420 when the position does not shift. As described above, the heat transfer tube inspection device 1A is not affected by the displacement of the bent portion 400 in the Z direction.

As described above, in the heat transfer tube inspection device 1A according to the first embodiment of the present invention, the profile sensor 30 is similar to the profile sensor 30 that detects the outer shape of the cross section of the bent portion 400 and the outer shape of the detected cross section. A control unit 50 for obtaining the diameter or radius of the approximate circle 420 is provided. Then, the control unit 50 determines whether or not the bent portion 400 is deformed beyond the permissible range based on the diameter or radius of the obtained approximate circle 420. In the heat transfer tube inspection device 1A, the presence or absence of deformation exceeding the permissible range can be determined only by obtaining the diameter of the approximate circle 420, so that it is easy to calculate the quality of the shape of the bent portion 400. Further, it is not necessary to calculate the three-dimensional shape of the surface of the bent portion 400 from the outer shape of the cross section, or to provide and compare the three-dimensional data as a reference for determination. As a result, in the heat transfer tube inspection device 1A, it is easy to inspect whether or not the bent portion 400 is deformed beyond the permissible range.

Since the diameter or radius of the approximate circle 420 obtained by the control unit 50 does not change even if the bent portion 400 is displaced in the Z direction, the heat transfer tube inspection device 1A accurately inspects the presence or absence of deformation regardless of the position of the bent portion 400. Can be done.

(Embodiment 2)
In the heat transfer tube inspection device 1A according to the first embodiment, the profile sensor 30 is moved by the drive unit 40. However, the present invention is not limited to this, and the profile sensor 30 may move relative to the bent portion 400 to be inspected. In the heat transfer tube inspection device 1B according to the second embodiment, in order to move the profile sensor 30 relative to the bent portion 400, the mounting portion 10 on which the heat exchanger 100 having the bent portion 400 is placed is moved. .. Hereinafter, the configuration of the heat transfer tube inspection device 1B according to the second embodiment will be described with reference to FIG. In the second embodiment, a configuration different from that of the first embodiment will be described.

FIG. 11 is a front view of the heat transfer tube inspection device 1B according to the second embodiment. As shown in FIG. 11, the heat transfer tube inspection device 1B includes a drive unit 60 that moves the mounting unit 10 in the X direction.

The drive unit 60 includes a motor 61 and a drive shaft 62 extending in the X direction to drive the mounting unit 10.

Like the motor 41, the motor 61 is composed of a servo motor, a stepping motor, and the like. Although not shown, the rotation of the motor 61 is controlled by the control unit 50.

The drive shaft 62 is connected to an output shaft (not shown) of the motor 61. A mounting portion 10 is screwed onto the drive shaft 62 and is rotated by driving the motor 61. Then, as the drive shaft 62 rotates, the mounting portion 10 moves in the X direction. In contrast, the profile sensor 30 remains fixed in place. As a result, the mounting portion 10 moves in the X direction relative to the profile sensor 30.

As described above, in the heat transfer tube inspection device 1B according to the second embodiment, the heat exchanger 100 mounted on the mounting portion 10 moves with respect to the profile sensor 30 by moving the mounting portion 10 in the X direction. Moves relatively in the X direction. Therefore, similarly to the first embodiment, the profile sensor 30 can detect the outer shape of the cross section of the bent portion 400 of the entire heat exchanger 100.

(Embodiment 3)
In the first and second embodiments, the heat transfer tube inspection devices 1A and 1B include a profile sensor 30 for inspecting the bent portion 400 for deformation. However, the present invention is not limited to this. In the present invention, the heat transfer tube inspection devices 1A and 1B may be provided with a detection unit that irradiates the bent portion 400 with light and detects the position of a part of the outer periphery of the cross section at a plurality of locations of the bent portion 400. Then, the heat transfer tube inspection devices 1A and 1B may obtain the shape of a part of the outer circumference from the detected position. The heat transfer tube inspection device 1C according to the third embodiment includes laser displacement sensors 31C, 31F, and 31B as detection units. Hereinafter, the configuration of the heat transfer tube inspection device 1C according to the third embodiment will be described with reference to FIGS. 12 and 13.

FIG. 12 is an enlarged front view of the laser displacement sensor 31C and the drive unit 70 of the heat transfer tube inspection device 1C according to the third embodiment. FIG. 13 is a cross-sectional view of the XIII-XIII cross-sectional line shown in FIG. In FIG. 12, the laser displacement sensors 31F and 31B are omitted from the laser displacement sensors 31C, 31F and 31B included in the heat transfer tube inspection device 1C for easy understanding. Moreover, the shape of the stage 73 is simplified.

As shown in FIGS. 12 and 13, the heat transfer tube inspection device 1C includes a drive unit 70 having the same configuration except for the drive unit 40 and the stage 73 of the first embodiment, and a laser moved in the X direction by the drive unit 70. It includes displacement sensors 31C, 31F, and 31B.

As shown in FIG. 12, the drive unit 70 includes a motor 71, a drive shaft 72, and a stage 73. The motor 71 and the drive shaft 72 have the same configuration as the motor 41 and the drive shaft 42 described in the first embodiment. Therefore, the description of the motor 71 and the drive shaft 72 will be omitted.

On the other hand, as shown in FIG. 13, the stage 73 is formed in the shape of a block recessed in the + Z direction. The recess of the stage 73 has an arc shape in a YZ cross-sectional view, and the center C3 of the arc is mounted on the mounting portion 10 described in the embodiment of the heat exchanger 100 and held by the holding portion 20. At that time, it is near the top of the bent portion 400 of the heat exchanger 100. The laser displacement sensors 31C, 31F, and 31B are fixed to the recesses of the stage 73.

The laser displacement sensors 31C, 31F, and 31B are sensors having a light emitting portion (not shown) that emits a spot-shaped laser beam L, unlike the profile sensor 30 described in the first embodiment.

The laser displacement sensor 31C is arranged at the position where the stage 73 is most recessed, that is, in the center of the stage 73 in a YZ cross-sectional view, and the laser displacement sensor 31F is arranged in front of the stage 73 and along the recess of the stage 73. The laser displacement sensor 31B is arranged behind the laser displacement sensor 31C and along the recess of the stage 73. Further, the laser displacement sensors 31C, 31F, and 31B are arranged at an equal angle with respect to the center C3 of the arc in the order of 31F, 31C, and 31B. Then, the laser displacement sensors 31C, 31F, and 31B direct the light emitting portion toward the center C3 of the above-mentioned arc. As a result, the laser displacement sensors 31C, 31F, and 31B are directed toward the top of the bent portion 400 near the center C3 of the arc when the heat exchanger 100 is mounted on the mounting portion 10 and held by the holding portion 20. And emits laser light L. Specifically, the laser displacement sensor 31C is directed toward the upper end of the bent portion 400, the laser displacement sensor 31F is directed toward the diagonally upper front portion of the bent portion 400, and the laser displacement sensor 31B is directed toward the diagonally upper rear portion of the bent portion 400. It emits light L.

The laser displacement sensors 31C, 31F, and 31B are provided with a light receiving portion as in the profile sensor 30 described in the first embodiment, and receive the reflected light when the above-mentioned laser light L is reflected from the top of the bent portion 400. Receive light. As a result, the laser displacement sensors 31C, 31F, and 31B measure the respective distances to the upper end portion, the front oblique upper portion, and the rear oblique upper portion of the bent portion 400.

As shown in FIG. 12, the heat transfer tube inspection device 1C includes a control unit 80. The control unit 80 acquires the distance data measured by the laser displacement sensors 31C, 31F, and 31B, and based on the distance data, each portion of the upper end portion, the front diagonally upper portion, and the rear diagonally upper portion of the bent portion 400. Find the arc that connects. The control unit 80 treats the radius of the obtained arc as the radius of the approximate circle 420 described in the first embodiment. From the approximate circle 420, the control unit 80 determines whether or not the bent portion 400 is deformed beyond the permissible range in the same manner as the control unit 50 of the first embodiment. As a result, the heat transfer tube inspection device 1C inspects the bent portion 400 for deformation exceeding the permissible range.

The operation of the heat transfer tube inspection device 1C is to measure the three distances to the upper end portion, the front diagonally upper portion, and the rear diagonally upper portion of the bent portion 400 with the laser displacement sensors 31C, 31F, and 31B. The operation is the same as that of the heat transfer tube inspection device 1A according to the first embodiment, except that the approximate circle 420 is obtained. Therefore, in the third embodiment, the description of the operation of the heat transfer tube inspection device 1C will be omitted.

As described above, in the heat transfer tube inspection device 1C according to the third embodiment, the approximate circle 420 is obtained based on the plurality of distance data measured by the laser displacement sensors 31C, 31F, and 31B, and the approximate circle 420 is further obtained. The inspection is performed for deformation of the bent portion 400 from 420 to exceed the allowable range. In the heat transfer tube inspection device 1C, since the presence or absence of deformation is inspected only by a plurality of distance data, the calculation of the inspection is easy.

In the third embodiment, the heat transfer tube inspection device 1C includes three laser displacement sensors 31C, 31F, and 31B, but the heat transfer tube inspection device 1C includes at least three laser displacement sensors 31C, 31F, and 31B. , You just have to prepare. This is because the approximate circle 420 can be obtained as long as there are at least three or more distance data.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments. For example, in the first to third embodiments, the bent portion 400 to be inspected has an inverted U shape. However, the present invention is not limited to this. In the present invention, the inspection target may be the bent portion 400 of the cylindrical heat transfer tube 300 bent in a U shape. Therefore, the orientation of the bent portion 400 is arbitrary. For example, the bent portion 400 may not be inverted U-shaped, but may be U-shaped as a matter of course. In this case, the profile sensor 30, the laser displacement sensors 31C, 31F, and 31B may face the bent portion 400 of the heat exchanger 100.

In the first to third embodiments, the bent portions 400 of the heat exchanger 100 are arranged in a row in the X direction. However, in the present invention, the number of rows of the bent portion 400 is arbitrary.

FIG. 14 is a side view of a modified example of the heat transfer tube inspection device 1A according to the first embodiment of the present invention. As shown in FIG. 14, when there are heat exchangers 100 arranged in two rows in the Y direction, the heat transfer tube inspection device 1D may inspect the bent portions 400 arranged in two rows in the entire heat exchanger 100 as an inspection target. Good. In this case, the heat transfer tube inspection device 1D may include two profile sensors 30 arranged in the Y direction.

Further, the heat transfer tube inspection device 1A-1D may inspect a plurality of bent portions 400 arranged in the X direction as described in the first and second embodiments.

In the first to third embodiments, the bent portions 400 of all the heat transfer tubes 300 of the heat exchanger 100 are to be inspected, but the present invention is not limited thereto. In the present invention, the profile sensor 30, the laser displacement sensors 31C, 31F, and 31B irradiate the bent portion 400, which is the inspection target described above, with light, and detect the position of a part of the outer periphery of the cross section at a plurality of locations of the bent portion 400. Just do it. The position of a part of the outer circumference may be the shape of a part of the outer circumference. Therefore, in the present invention, not all the bent portions 400 need to be inspected, and some bent portions 400 may be inspected. Further, only a part of the bent portion 400 may be inspected. For example, if there is a tendency in the distribution of the parts where the pipe deformation occurs and the parts where the pipe deformation does not occur from the analysis result of the inspection data of the bent portion 400, the inspection target may be limited to a specific place based on the distribution. .. As a result, the inspection time of the heat transfer tube inspection device 1A-1D can be shortened, and the productivity is improved.

In the third embodiment, the heat transfer tube inspection device 1C includes three laser displacement sensors 31C, 31F, and 31B. Further, the heat transfer tube inspection device 1D shown in FIG. 14 includes two profile sensors 30. However, the present invention is not limited to this. In the present invention, the profile sensor 30, the laser displacement sensors 31C, 31F, and 31B need only be able to irradiate the bent portion 400 to be inspected with light and detect the position of a part of the outer periphery of the cross section at a plurality of locations of the bent portion 400. Therefore, the number, type, arrangement, and the like of the profile sensor 30, the laser displacement sensors 31C, 31F, and 31B are arbitrary as long as they are the detectors capable of the above-mentioned detection.

For example, in the heat transfer tube inspection device 1A-1C, profile sensors 30 may be provided in front of and behind the bent portion 400, that is, on the −Y side and the + Y side of the bent portion 400, respectively. In this case, the profile sensors 30 may detect the shape of the entire outer circumference of the cross section at a plurality of points of the bent portion 400, that is, the entire circumference of 360 ° around the pipe axis.

In the first and second embodiments, the control unit 50 obtains the diameter or radius of the approximate circle 420 that approximates the outer shape of the cross section based on the shape data of the cross section of the bent portion 400 acquired from the profile sensor 30. .. Further, in the third embodiment, the control unit 80 obtains the diameter or radius of the approximate circle 420 based on a plurality of distance data acquired from the laser displacement sensors 31C, 31F, and 31B. However, the present invention is not limited to this. In the present invention, the control units 50 and 80 set a circle having an arc that approximates the position of a part of the outer circumference of the cross section detected by the profile sensor 30 or the laser displacement sensors 31C, 31F and 31B at each of a plurality of inspection targets. do it. Then, the control units 50 and 80 may determine the quality of the heat transfer tube based on the correspondence between the positions of the plurality of locations and the set size of the circle.

For example, the control units 50 and 80 may obtain an arc that approximates the position of a part of the outer periphery of the cross section of each of the plurality of locations in the bent portion 400. Further, since the control units 50 and 80 may determine the quality of the heat transfer tube using the set size of the circle, the radius or the diameter, which is an element for specifying the size of the circle, as well as the circumference and the circle. The quality of the heat transfer tube may be determined by using the area, the length of the arc within a specific angle, the area of the fan shape formed by the arc, and the like.

The control units 50 and 80 may determine the quality of the heat transfer tube based on, for example, the degree of change between the positions of a plurality of locations and the diameter, radius, or circumference. Here, in the first and third embodiments, the quality of the heat transfer tube is determined by the presence or absence of deformation exceeding the allowable range, that is, the range within the predetermined design standard, but the design standard is from a perfect circle. When the degree of deformation of the heat transfer tube is specified, the quality of the heat transfer tube should be judged as to whether the degree of deformation of the heat transfer tube is within the design standard.

In the first to third embodiments, the heat transfer tube inspection program is stored in the storage unit 51 provided in the heat transfer tube inspection device 1A. However, the medium in which the heat transfer tube inspection program is stored is not limited to the storage unit 51 provided in the heat transfer tube inspection device 1A. The heat transfer tube inspection program includes CD-ROM (Compact Disc Read Only Memory), DVD (Digital Versatile Disc), magneto-optical disc (Magneto-Optical Disc), USB (Universal Serial Bus) memory, memory card, HDD (Hard Disk Drive). It is also possible to store and distribute it on a computer-readable recording medium such as). Then, by installing the heat transfer tube inspection program distributed in this way on a specific or general-purpose computer, it is possible to make the computer function as the control units 50 and 80.

In the first and second embodiments, the holding portion 20 is composed of two plates, and the heat exchanger 100 is sandwiched between the two plates. However, the configuration of the holding unit 20 is arbitrary as long as the heat exchanger 100 is held. For example, the holding unit 20 may be configured to sandwich and hold the heat exchanger 100 from both the + X direction and the −X direction. Further, the holding portion 20 may be a recess formed in the mounting portion 10 and into which the heat exchanger 100 is fitted.

The present invention allows for various embodiments and modifications without departing from the broad spirit and scope of the present invention. Moreover, the above-described embodiment is for explaining the present invention, and does not limit the scope of the present invention. That is, the scope of the present invention is indicated not by the embodiment but by the claims. And various modifications made within the scope of the claims and within the equivalent meaning of the invention are considered to be within the scope of the present invention.

This application is based on Japanese Patent Application No. 2018-96538 filed on May 18, 2018. The specification, claims, and drawings of Japanese Patent Application No. 2018-96538 are incorporated herein by reference.

1A, 1B, 1C Heat transfer tube inspection device, 10 mounting part, 20 holding part, 21 plate-shaped body, 30 profile sensor, 31C, 31F, 31B laser displacement sensor, 40 drive part, 41 motor, 42 drive shaft, 43 stage , 50 control unit, 51 storage unit, 52 CPU, 60 drive unit, 61 motor, 62 drive shaft, 70 drive unit, 71 motor, 72 drive shaft, 73 stage, 80 control unit, 410 outer shape, 420 approximate circle, C1 Center, C2 center, C3 center, D1 deformation part, E detection end position, L laser light, L1 distance, S detection start position, T1, T2 top, 100 heat exchanger, 200 fins, 300 heat transfer tube, 400 bent part.

Claims (6)

Irradiate the bent portion of the U-shaped bent cylindrical heat transfer tube with light, and a plurality of portions on the outer periphery of the cross section at a plurality of locations of the bent portion, including the top, located in the bending direction of the heat transfer tube. A detector that detects the position of each minute and
The detection portion is detected by each of the plurality of positions, and set the circle having an arc that approximates the plurality of parts of the respective positions on the outer periphery of the cross section, of the arc approximated by the plurality of positions, respectively, wherein When there is an arc larger than the arc at the top of the bent portion, a determination unit for determining that the heat transfer tube is defective, and a determination unit.
Heat transfer tube inspection device equipped with. A holding portion that holds the bent portion and
A drive unit that moves the detection unit relative to the bent portion held by the holding unit,
Further prepare,
The heat transfer tube inspection device according to claim 1. The heat transfer tube has a plurality of the bent portions, and the plurality of the bent portions are arranged in one direction.
The drive unit moves the detection unit in the one direction.
The heat transfer tube inspection device according to claim 2. The detection unit detects the positions of at least three portions on the outer circumference of the cross section at a plurality of locations of the bent portion, including the top, located in the bending direction of the heat transfer tube.
The heat transfer tube inspection device according to any one of claims 1 to 3. Of the bent portion of the cylindrical heat transfer tubes bent in a U-shape, includes a top, the detection step of detecting a plurality of parts of the respective positions on the outer periphery of the cross section at a plurality of positions located in the direction in which the heat transfer tube bends When,
Detected by said plurality of positions, respectively by the detecting step, and a circle setting step of setting a circle having an arc that approximates the plurality of parts of the respective positions on the outer periphery of said cross section,
Among the arc approximated by previous SL circle respectively set the plurality of positions set in step, when there is greater the arc than the arc at the top portion of the bent portion determines that the heat transfer tube is defective Judgment process and
Heat transfer tube inspection method equipped with. A computer that controls a heat transfer tube inspection device equipped with a detector that detects the position of a part of the outer circumference of the cross section of the heat transfer tube.
Of the bent portion of the cylindrical heat transfer tubes bent in a U-shape, includes a top, detecting a plurality of parts each correspond to positions on the outer periphery of the cross section at a plurality of positions located in the direction in which the heat transfer tube bends When,
Detected by said plurality of positions, respectively by the detecting step, and a circle setting step of setting a circle having an arc that approximates the plurality of parts of the respective positions on the outer periphery of said cross section,
Among the arc approximated by previous SL circle respectively set the plurality of positions set in step, when there is greater the arc than the arc at the top portion of the bent portion determines that the heat transfer tube is defective Judgment step and
A program to execute.

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