JP5332941B2 - Measuring head for inner surface inspection equipment - Google Patents

Description

  The present invention relates to a measuring head of an inner peripheral surface inspection apparatus that inspects a surface and an internal defect on an inner peripheral surface facing a bore of an object to be inspected, and in particular, a cylinder inner peripheral surface facing a cylinder bore of an engine cylinder or a cylinder block. The present invention relates to a measuring head of an inner peripheral surface inspection apparatus that inspects a surface and an internal defect.

  In the inner peripheral surface inspection apparatus for inspecting the surface and internal defects on the inner peripheral surface of the cylinder facing the cylinder bore of the engine cylinder or cylinder block, as shown in FIG. However, it is installed with the sensor surface facing outward. The measuring head 100 is inserted into the cylinder bore by a lifting unit (not shown) and inspected for defects existing on the inner peripheral surface of the cylinder and inside, for example, a cast hole and a flaw, while being rotated by a rotating unit (not shown). To do.

  By the way, in the eddy current flaw detection sensor 101, if the distance between the sensor surface and the cylinder inner peripheral surface changes during the detection, the change in the distance greatly affects the detection result. For example, even when the cylinder block is fixed and the measuring head 100 always moves with the same locus relative to the cylinder block, the cylinder bore position of the cylinder block, the diameter of the cylinder inner peripheral surface, the cylinder inner peripheral surface Due to variations in inclination or the like, the distance between the eddy current flaw detection sensor 101 and the inner peripheral surface of the cylinder may change during detection by the eddy current flaw detection sensor 101, and the defect may not be detected.

  Therefore, as described in Patent Document 1, a displacement sensor is additionally installed in the measurement head, the distance between the displacement sensor and the cylinder inner peripheral surface is measured, and the XY table is driven based on the measured value. There is known an inspection apparatus that corrects the position of the head and thereby maintains a constant distance between the flaw detection sensor and the inner peripheral surface of the cylinder.

JP 2003-294710 A

  In the inspection apparatus described in Patent Document 1, for example, the position of a measurement head that rotates at a rotation speed of 800 rpm is corrected in real time in the X direction and the Y direction using an XY table. However, such position correction is difficult to control due to processing time, responsiveness of the XY table driving unit, and the like, and in order to realize this, a complicated and expensive inspection apparatus is required.

  The object of the present invention has been made in consideration of the above-mentioned circumstances, and maintains the distance between the sensor surface of the flaw detection sensor and the inner peripheral surface of the inspection object constant with a simple structure, and the inner peripheral surface. Another object of the present invention is to provide a measuring head for an inner peripheral surface inspection apparatus that can detect a surface defect and an internal defect with high accuracy.

The present invention relates to a measuring head of an inner peripheral surface inspection apparatus that is inserted into a bore of an object to be inspected, rotates in the circumferential direction of the inner peripheral surface facing the bore, and inspects the surface of the inner peripheral surface and internal defects. A measuring head body having a frame, a moving base, a flaw detection sensor , a guide roller, and a displacement sensor , wherein the moving base moves in a diameter direction of an inner peripheral surface of the inspection object with respect to the frame. The flaw detection sensor is attached to the moving base, the sensor surface faces the inner peripheral surface of the object to be inspected, detects the surface of the inner peripheral surface and internal defects, and the guide roller the said moving base, a both sides of the flaw sensor in plan view, is attached at a position of the flaw sensor the same height as viewed from the side, the moving base during rotation of the measuring head Go radially outwardly of the inner peripheral surface with the scan, whereas that consists to roll in pressed state to the inner circumferential surface, said the moving base on the flaw sensor coaxially, and the flaw detection A displacement sensor for determining a change in the distance between the sensor surface of the flaw detection sensor and the inner peripheral surface of the inspection object is disposed at a position opposite to the sensor .

  According to the present invention, when the measuring head is rotated, the moving base moves outward in the radial direction of the inner peripheral surface of the object to be inspected, and the guide roller attached to the moving base is pressed against the inner peripheral surface. Thus, the flaw detection sensor attached to the moving base is positioned following the inner peripheral surface. For this reason, the distance between the sensor surface of the flaw detection sensor and the inner peripheral surface of the object to be inspected can be kept constant with a simple structure. As a result, the flaw detection sensor increases the surface and internal defects on the inner peripheral surface of the inspection object. It can be detected with accuracy.

The cylinder inner peripheral surface defect inspection apparatus to which one embodiment in the measuring head of the inner peripheral surface inspection apparatus according to the present invention is applied is shown, (A) is a front view, (B) is an IB arrow in FIG. Visual view. The perspective view which shows the measuring head of FIG. FIG. 3 is a perspective view showing the measuring head of FIG. 2 as viewed from obliquely below. (A) is a side view showing the measuring head of FIG. 2, (B) is a partially enlarged view of FIG. 4 (A). The bottom view which shows the measuring head of FIG. FIG. 3 is an assembled perspective view of the measurement head of FIG. 2. FIG. 7 is a bottom view showing two types of spacers in FIG. 6. The perspective view which shows the position adjustment condition of the eddy current flaw detection sensor using a setting gauge. The assembly perspective view which shows the setting gauge of FIG. The perspective view which shows the measuring head of the conventional inner peripheral surface test | inspection apparatus.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  1A and 1B show a cylinder inner peripheral surface defect inspection apparatus to which an embodiment of a measuring head of an inner peripheral surface inspection apparatus according to the present invention is applied. FIG. 1A is a front view, and FIG. It is an IB arrow line view of). A cylinder inner peripheral surface defect inspection device 10 as an inner peripheral surface inspection device shown in FIG. 1 includes a surface and an inner surface of each cylinder inner peripheral surface 3 facing a plurality of cylinder bores 2 of a cylinder or a cylinder block 1 as an inspection object. In this case, the elevating unit 11, the rotating unit 12, and the measuring head 13 are configured.

  The elevating unit 11 is attached to a fixed plate 15 fixed to the gantry 14 with, for example, a servo motor 16 as an elevating drive source fixed, and a ball screw 17 extends vertically downward on a rotation shaft of the servo motor 16. A nut 19 installed on the back surface of the slide plate 18 is screwed into the ball screw 17.

  The rotation unit 12 has a motor 20 installed on the surface of the slide plate 18 as a rotation drive source, and a rotation shaft 22 connected to the motor 20 via a timing belt 21 and the like. The rotary shaft 22 is rotatably supported on the slide plate 18 by a bearing unit 23 installed on the slide plate 18. The measuring head 13 is attached to the lower end of the rotating shaft 22.

  Therefore, the drive of the servo motor 16 moves the slide plate 18 up and down via the ball screw 17 and the nut 19. Further, the rotation shaft 22 is rotated via the timing belt 21 by the driving of the motor 20. As a result, the measuring head 13 is inserted into the cylinder bore 2 of the cylinder block 1 and rotates along the circumferential direction of the cylinder inner peripheral surface 3 to inspect the surface and internal defects of the cylinder inner peripheral surface 3. At the time of this inspection, the measuring head 13 moves up and down by a certain distance in the axial direction of the cylinder inner peripheral surface 3 every time it rotates, for example, relative to the cylinder inner peripheral surface 3. Inspect the entire surface for defects.

  2 to 4, the measurement head 13 includes a measurement head main body 29 including a frame 24, a moving base 25, an eddy current flaw detection sensor 26, a guide roller 27, and an eddy current displacement sensor 28, and the measurement head main body 29. And a spacer 30 for coupling to the rotating shaft 22. A rotational force and a lifting / lowering moving force from the rotary shaft 22 are applied to the measurement head main body 29 via the spacer 30.

  The frame 24 is formed by hanging a pair of frame hanging parts 24B integrally from the bottom surface of the frame plane part 24A. A guide bush 31A is fitted to the tip of each of the pair of frame hanging parts 24B. Each of the pair of guide bars 31 having one end fixed to the arm portion 25A of the moving base 25 is inserted into each guide bush 31A.

  As shown in FIGS. 4 and 5, these guide bars 31 are arranged on both sides of the eddy current flaw detection sensor 26 in parallel with the eddy current flaw detection sensor 26 and at the same height as the eddy current flaw detection sensor 26. By these guide bars 31, the moving base 25 is attached to the frame hanging portion 24B so as to be movable only in the axial direction of the eddy current flaw detection sensor 26, that is, in the diameter direction of the cylinder inner peripheral surface 3.

  2 and 3, a compression spring 32 is disposed coaxially with the guide bar 31 between both arm portions 25A of the moving base 25 and the frame hanging portion 24B. A stopper 33 is fixed to the other end. When the stopper 33 comes into contact with the guide bush 31A, the movement of the moving base 25 by the spring force of the compression spring 32 is restricted (restrained).

  The eddy current flaw detection sensor 26 detects a defect on the surface and inside of the cylinder inner peripheral surface 3 of the cylinder block 1 and is attached to the sensor housing 34. The sensor housing 34 is fixed to the moving base 25 using a mounting screw 35. By loosening the mounting screw 35, the axial direction of the eddy current flaw detection sensor 26 with respect to the moving base 25 (that is, the cylinder inner peripheral surface 3). (In the diameter direction) can be finely adjusted. The sensor housing 34 is made of plastic, for example, in order to avoid an influence on detection of eddy current flaw detection. With the eddy current flaw detection sensor 26 attached to the moving base 25 via the sensor housing 34, the sensor surface 36 of the eddy current flaw detection sensor 26 faces the cylinder inner peripheral surface 3 of the cylinder block 1 as shown in FIG. Provided.

  As shown in FIGS. 4 and 5, the guide roller 27 is rotatably installed in front of each of the pair of arm portions 25 </ b> A in the moving base 25. The pair of guide rollers 27 are disposed on both sides of the eddy current flaw detection sensor 26 in a plan view or a bottom view (FIG. 5), and are positioned at the same height as the eddy current flaw detection sensor 26 in a side view (FIG. 4). These guide rollers 27 come into contact with the cylinder inner peripheral surface 3 when the measuring head 13 is inserted into the cylinder bore 2 of the cylinder block 1. At this time, the sensor surface 36 of the eddy current flaw detection sensor 26 and the cylinder inner peripheral surface 3. The position of the sensor housing 34 is adjusted with respect to the moving base 25 using a setting gauge 47 (described later) shown in FIG.

  Furthermore, as shown in FIG. 5, when the center of the cylinder bore 2 (that is, the center O of the cylinder inner peripheral surface 3) and the rotation center P of the measuring head 13 are shifted, the pair of guide rollers 27 is connected to the measuring head 13. When rotating along the circumferential direction of the cylinder inner peripheral surface 3 (for example, when rotating in the direction of arrow A in FIG. 5), the centrifugal force acting on the moving base 25 and the spring force of the compression spring 32 cause the cylinder inner periphery together with the moving base 25. It moves to the outer side in the radial direction of the surface 3 and is pressed by the cylinder inner peripheral surface 3 to roll. Accordingly, the moving base 25 moves following the position of the cylinder inner peripheral surface 3, and as a result, the eddy current flaw detection sensor 26 attached to the moving base 25 via the sensor housing 34 also follows the cylinder inner peripheral surface 3. Positioned. Therefore, even when the center O of the cylinder inner peripheral surface 3 and the rotation center P of the measuring head 13 are deviated, the distance M between the sensor surface 36 of the eddy current flaw detection sensor 26 and the cylinder inner peripheral surface 3 is the above-mentioned suitability. A constant value (for example, 0.3 mm) is maintained.

  Here, the guide roller 27 is made of plastic and prevents the cylinder inner peripheral surface 3 from being damaged when contacting the cylinder inner peripheral surface 3.

  As shown in FIGS. 4 and 5, each of the pair of guide rollers 27 comes into contact with the peripheral edge portion 4 of the cylinder inner peripheral surface 3 when the measuring head 13 is inserted into the cylinder bore 2 of the cylinder block 1. Thus, a tapered surface 37 is formed for moving the moving base 25 inward (in the center O side of the cylinder inner peripheral surface 3) in the radial direction of the cylinder inner peripheral surface 3.

  When the measuring head 13 does not exist in the cylinder bore 2 (that is, when the movement of the moving base 25 is stopped by the stopper 33), the rotation center P of the measuring head 13 moves to the cylinder inner peripheral surface 3 of the guide roller 27. The distance L to the contact point is set to be, for example, about 0.5 mm larger than the radius of the cylinder inner peripheral surface 3 in order to cope with variations in accuracy of the cylinder inner peripheral surface 3. When the measuring head 13 approaches the cylinder bore 2, the tapered surface 37 of the guide roller 27 of the measuring head 13 comes into contact with the peripheral edge 4 of the cylinder inner peripheral surface 3, and the force F acting on the tapered surface 37 from the peripheral edge 4. The radial component force Fx of FIG. 4B (FIG. 4B) resists the urging force of the compression spring 32 by moving the moving base 25 inward in the axial direction of the eddy current flaw detection sensor 26 (that is, radially inward of the cylinder inner peripheral surface 3). To move. As a result, the measuring head 13 is guided by the tapered surface 37 of the guide roller 27 and inserted into the cylinder bore 2. A state in which the measuring head 13 is inserted into the cylinder bore 2 is shown in FIGS.

  The taper angle θ that forms the tapered surface 37 of the guide roller 27 is such that the radial component force Fx is greater than the axial component force Fy of the force F acting on the tapered surface 37 from the peripheral edge 4 of the cylinder inner peripheral surface 3. A small angle is set so as to increase.

  The tapered surface 37 of the guide roller 27 is provided below the guide roller 27, and is formed in a region below the lower end 26 </ b> A of the eddy current flaw detection sensor 26 in a side view of the measurement head 13. Therefore, when the measuring head 13 is guided by the tapered surface 37 of the guide roller 27 and inserted into the cylinder bore 2, the eddy current flaw detection sensor 26 does not interfere (collision) with the cylinder inner peripheral surface 3, and the measurement is further performed. When the head 13 is inserted into the cylinder bore 2, the distance M between the sensor surface 36 of the eddy current flaw detection sensor 26 and the cylinder inner peripheral surface 3 is set to the above-described constant value (for example, 0.3 mm).

  As shown in FIGS. 3 and 4, the sensor housing 34 fixed to the moving base 25 is provided with the eddy current displacement sensor 28 coaxially with the eddy current flaw detection sensor 26 and at a position opposite to the eddy current flaw detection sensor 26. It is set using the sensor bracket 39. This eddy current displacement sensor 28 is for obtaining a change in the distance M between the sensor surface 36 of the eddy current flaw detection sensor 26 and the cylinder inner peripheral surface 3, and the distance N between the sensor surface 38 and the cylinder inner peripheral surface 3. (FIG. 5) is measured. This distance N is set to an appropriate constant value of, for example, 1.0 mm when the measuring head 13 is inserted into the cylinder bore 2 and the guide roller 27 comes into contact with the cylinder inner peripheral surface 3.

  The measurement head 13 is inserted into the cylinder bore 2 in a state where the center of the cylinder bore 2 (center O of the cylinder inner peripheral surface 3 (FIG. 5)) and the rotation center P of the measurement head 13 are shifted, and the measurement head 13 is inserted into the cylinder inner periphery. When rotating along the circumferential direction of the surface 3, the eddy current displacement sensor 28 is attached to the sensor housing 34 and moves along with the position of the cylinder inner circumferential surface 3 together with the eddy current flaw detection sensor 26. At this time, since the eddy current flaw detection sensor 26 and the eddy current displacement sensor 28 are disposed at positions opposite to each other by 180 degrees, when the eddy current flaw detection sensor 26 approaches the cylinder inner peripheral surface 3, the eddy current displacement sensor 28 is moved to the cylinder by the same amount. It will be separated from the inner peripheral surface 3. Therefore, by measuring the change in the distance N between the sensor surface 38 of the eddy current displacement sensor 28 and the cylinder inner peripheral surface 3, the measured value and the value of the diameter of the cylinder inner peripheral surface 3 are used to determine the eddy current flaw detection sensor 26. It is possible to calculate a change in the distance M between the sensor surface 36 and the cylinder inner peripheral surface 3.

  The eddy current flaw detection sensor 26 has a characteristic that the detection accuracy is greatly affected by a change in the distance M between the sensor surface 36 and the cylinder inner peripheral surface 3. The distance M is maintained at a suitable constant value (for example, 0.3 mm) as described above, but may change for some reason. Therefore, as described above, a change in the distance M between the sensor surface 36 of the eddy current flaw detection sensor 26 and the cylinder inner peripheral surface 3 is obtained based on the measurement value of the eddy current displacement sensor 28, and the eddy current flaw detection sensor 26 is obtained based on this value. By correcting the detection data, it is possible to stabilize and improve the accuracy of defect detection by the eddy current flaw detection sensor 26.

  Next, a spacer 30 that couples the measuring head main body 29 including the eddy current flaw detection sensor 26, the guide roller 27, the eddy current displacement sensor 28, and the like to the rotating shaft 22 will be described with reference to FIGS.

  As shown in FIG. 4, when the measurement head 13 is not present in the cylinder bore 2 and the operation of the moving base 25 is stopped by the stopper 33, the guide roller 27 is moved from the rotation center P (FIG. 5) of the measurement head 13. As described above, the distance L to the contact point with the cylinder inner peripheral surface 3 is set to be, for example, about 0.5 mm larger than the radius of the cylinder inner peripheral surface 3. Therefore, the margin in the radial direction of the measurement head 13 (measurement head body 29) for inserting the measurement head 13 (measurement head body 29) into the cylinder bore 2 is, for example, about 0.5 mm. For this reason, the radius range of the cylinder inner peripheral surface 3 that can be handled by the measurement head main body 29 itself is as small as about ± 0.25 mm, for example. Therefore, in order to inspect defects on the inner circumferential surface 3 of the cylinder having different radii using the measuring head body 29, the center of the measuring head body 29 and the rotation center P of the measuring head 13 (that is, the rotation) It is necessary to change the distance from the rotation center of the shaft 22.

  In the present embodiment, in order to change the distance between the center of the measurement head main body 29 and the rotation center P of the measurement head 13, a plurality of types of spacers 30 (for example, FIG. The spacers 30A and 30B) shown in FIG. 7 are used.

  That is, an inlay portion 41 that engages with the engagement convex portion 40 of the rotary shaft 22 is provided on the bottom surface of the spacer 30 (30A, 30B). The spacers 30 (30 </ b> A and 30 </ b> B) are positioned with respect to the rotary shaft 22 by the engagement of the engagement convex portions 40 and the spigot portions 41. Further, a groove 42 that engages with the frame flat surface portion 24A of the measurement head main body 29 and a pin hole 44 that engages with the positioning pin 43 of the measurement head main body 29 are formed on the top surface of the spacer 30 (30A, 30B). Has been. The frame head portion 29 is positioned with respect to the spacer 30 (30A, 30B) by the frame flat portion 24A engaging with the groove 42 and the positioning pin 43 fitting into the pin hole 44.

  In the spacer 30A and the spacer 30B, as shown in FIG. 7, the dimension S between the center of the spigot part 41 as the engaging part and the pin hole 44 as the positioning part is different, and the dimension SA of the spacer 30A is the same as that of the spacer 30B. It is set larger than the dimension SB. Therefore, the measuring head 29 is coupled to the rotary shaft 29 via the spacer 30A for the cylinder inner peripheral surface 3 having a large diameter, and the measuring head 29 is connected to the cylinder inner peripheral surface 3 having a small diameter via the space 30B. Is coupled to the rotating shaft 22. Thereby, the distance between the center of the measurement head main body 29 and the rotation center P of the measurement head 13 (the rotation center of the rotary shaft 22) can be made different according to the diameter of the cylinder inner peripheral surface 3. Here, the measurement head main body 29 is coupled to the spacer 30 (30A, 30B) using a fastening bolt 48, and the spacer 30 (30A, 30B) is coupled to the rotary shaft 22 using a fastening bolt 49.

  In this way, by using the spacer 30 (30A, 30B), the distance between the center of the measurement head body 29 and the rotation center P of the measurement head 13 is changed according to the diameter of the cylinder inner peripheral surface 3, whereby the measurement head body. 29, the distance M between the sensor surface 36 of the eddy current flaw detection sensor 26 and the cylinder inner peripheral surface 3 is maintained at an appropriate constant value of 0.3 mm, for example.

  Also in the eddy current displacement sensor 28 of the measuring head main body 29, a plurality of types of sensor brackets 39 (for example, a sensor bracket 39A for the cylinder inner peripheral surface 3 having a large diameter, A sensor bracket 39B) for a small cylinder inner peripheral surface 3 is prepared. By changing the sensor bracket 39 (39A, 39B) according to the diameter of the cylinder inner peripheral surface 3, the distance N between the sensor surface 38 of the eddy current displacement sensor 28 and the cylinder inner peripheral surface 3 in the measurement head main body 29 is For example, it is held at an appropriate constant value of 1.0 mm.

  As described above, when the distance between the center of the measurement head main body 29 and the rotation center P of the measurement head 13 is changed according to the diameter of the cylinder inner peripheral surface 3 by using the spacer 30 (30A, 30B), particularly in the cylinder. When the diameter of the peripheral surface 3 is large, the center of the measurement head main body 29 is far away from the rotation center P of the measurement head 13, and in this measurement head 13, the unbalance around the rotation center P becomes excessive and vibration is generated. Resulting in. Therefore, a balance weight 46 that is increased or decreased according to the dimension S (SA, SB) between the center of the spigot portion 41 and the pin hole 44 is attached to the weight attachment portion 45 of the spacer 30 (30A, 30B). By adjusting the weight of the balance weight 46, the unbalance of the measurement head 13 described above is eliminated.

  Next, a setting gauge 47 for adjusting the position of the eddy current flaw detection sensor 26 with respect to the guide roller 27 will be described with reference to FIGS.

  The setting gauge 47 has an appropriate distance M between the sensor surface 36 of the eddy current flaw detection sensor 26 and the cylinder inner peripheral surface 3 of 0.3 mm, for example, when the guide roller 27 of the measuring head 13 contacts the cylinder inner peripheral surface 3. As shown in FIG. 9, the dial gauge 50, the gauge base 51, and the gauge master 52 are provided.

  The dial gauge 50 is fixedly attached to the gauge attachment bracket 53. The gauge base 51 is attached to the gauge mounting bracket 53 in a replaceable manner, and includes a curved concave surface 54 formed to have the same radius as the radius of the cylinder inner peripheral surface 3. The gauge master 52 includes a curved convex surface 55 formed to have the same radius as the radius of the cylinder inner peripheral surface 3, and a coupling hole 56 is formed. By inserting the coupling bolt 57 projecting from the gauge base 51 into the coupling hole 56 of the gauge master 52 and coupling them, the curved convex surface 55 of the gauge master 52 is in contact with the curved concave surface 54 of the gauge base 51. A master 52 is attached to the gauge base 51.

  The dial gauge 50 is attached to the gauge base 51 via the gauge mounting bracket 53, and the gauge 58 is attached to the gauge base 51 with the gauge 58 in contact with the curved convex surface 55 of the gauge master 52. The dial gauge 50 is set to zero.

  Next, the gauge master 52 is detached from the gauge base 51, and the guide roller 27 of the measuring head 13 is brought into contact with the curved concave surface 54 of the gauge base 51 as shown in FIG. At this time, the probe 58 of the dial gauge 50 is set to be perpendicular to the sensor surface 36 of the eddy current flaw detection sensor 26 of the measurement head 13. In this state, the sensor housing 34 to which the eddy current flaw detection sensor 26 is attached is finely moved in the axial direction of the eddy current flaw detection sensor 26 with respect to the moving base 25 so that the numerical value of the dial gauge 50 becomes −0.3 mm, for example. The position of the sensor surface 36 of the eddy current flaw detection sensor 26 is adjusted.

  In the setting gauge 47, when the radius of the cylinder inner peripheral surface 3 of the cylinder block 1 to be inspected is different, the curved concave surface 54 and the curved convex surface 55 having the same radius as the radius of the cylinder inner peripheral surface 3 are provided. A gauge base 51 and a gauge master 52 respectively provided are used.

  With the configuration as described above, the following effects (1) to (10) are achieved according to the present embodiment.

  (1) When the measuring head 13 inserted into the cylinder bore 2 of the cylinder block 1 rotates, the moving base 25 moves outward in the radial direction of the cylinder inner peripheral surface 3, and a guide roller 27 attached to the moving base 25 The eddy current flaw detection sensor 26 attached to the moving base 25 moves following the position of the cylinder inner peripheral surface 3 by rolling while being pressed against the cylinder inner peripheral surface 3. For this reason, since the distance M between the sensor surface 36 of the eddy current flaw detection sensor 26 and the cylinder inner peripheral surface 3 can be maintained at an appropriate constant value with a simple structure, the cylinder inner peripheral surface 3 of the cylinder block 1 by the eddy current flaw detection sensor 26. The surface and internal defects in can be detected with high accuracy.

  (2) Since the eddy current flaw detection sensor 26 is installed at the same height as the pair of guide rollers 27, the sensor surface 36 of the eddy current flaw detection sensor 26 is at the same height as the guide roller 27 and at the position of the cylinder inner peripheral surface 3. It can be followed accurately.

  (3) When the measuring head 13 inserted into the cylinder bore 2 of the cylinder block 1 rotates, the guide roller 27 and the moving base 25 are moved into the cylinder by the centrifugal force acting on the moving base 25 and the spring force of the compression spring 32. It moves to the outer side in the radial direction of the peripheral surface 3 and is pressed and rolled by the cylinder inner peripheral surface 3. For this reason, the moving base 25 moves following the position of the cylinder inner peripheral surface 3, and the eddy current flaw detection sensor 26 attached to the moving base 25 via the sensor housing 34 also follows the position of the cylinder inner peripheral surface 3. . As a result, the followability of the eddy current flaw detection sensor 26 can be stabilized as compared with the case where the eddy current flaw detection sensor 26 is caused to follow the position of the cylinder inner peripheral surface 3 only by the centrifugal force acting on the moving base 25 when the measuring head 13 rotates. .

  (4) When the measuring head 13 is inserted into the cylinder bore 2, the guide roller 27 contacts the peripheral edge 4 of the cylinder inner peripheral surface 3 and moves the moving base 25 inward of the cylinder inner peripheral surface 3 in the radial direction. A tapered surface 37 is formed. Therefore, even when the center of the cylinder bore 2 (center O of the cylinder inner peripheral surface 3) and the rotation center P of the measurement head 13 (rotation center of the rotary shaft 22) are deviated, the measurement head 13 is placed in the cylinder bore 2. It is not necessary to provide a mechanism that can be easily inserted and that performs an operation of causing the rotation center P of the measuring head 13 to coincide with the center O of the cylinder inner peripheral surface 3.

  (5) Since the tapered surface 37 of the guide roller 27 is formed in a region below the lower end 26 </ b> A of the eddy current flaw detection sensor 26 in the side view of the measuring head 13, the measuring head 13 is formed on the tapered surface 37 of the guide roller 27. When guided and inserted into the cylinder bore 2, the eddy current flaw detection sensor 26 can be prevented from interfering with the cylinder inner peripheral surface 3.

  (6) The eddy current flaw detection sensor 26 has a characteristic that the detection accuracy is greatly affected by a change in the distance M between the sensor surface 36 and the cylinder inner peripheral surface 3. The distance M is maintained at a suitable constant value (for example, 0.3 mm) as described above, but may change for some reason. An eddy current displacement sensor 28 is installed in the measuring head 13, and the eddy current displacement sensor 28 measures the change in the distance N between the sensor surface 38 and the cylinder inner peripheral surface 3, thereby detecting the sensor surface of the eddy current flaw detection sensor 26. A change in the distance M between 36 and the cylinder inner peripheral surface 3 is obtained. Since the output data of the eddy current flaw detection sensor 26 is corrected based on the change in the distance M, the defect detection accuracy of the cylinder inner peripheral surface 3 by the eddy current flaw detection sensor 26 can be stabilized and improved.

  (7) Since the eddy current displacement sensor 28 is disposed coaxially with the eddy current flaw detection sensor 26 in the sensor housing 34 of the measuring head 13, for example, the eddy current displacement sensor 28 is positioned above or below the eddy current flaw detection sensor 26. Compared with the case where the flaw detection sensor 26 is arranged in parallel, the eddy current flaw detection sensor 26 and the cylinder inner peripheral surface are measured from the measured value (change in the distance N) of the eddy current displacement sensor 28 at the same position relative to the cylinder inner peripheral surface 3. 3 can be obtained. Therefore, correction of the detection data of the eddy current flaw detection sensor 26 based on the change of the distance M can be appropriately performed.

  (8) The eddy current displacement sensor 28 is disposed at a position opposite to the eddy current flaw detection sensor 26 in the sensor housing 34 of the measuring head 13. That is, both the eddy current flaw detection sensor 26 and the eddy current displacement sensor 28 perform detection and measurement using electromagnetics. The eddy current flaw detection sensor 26 and the eddy current displacement sensor 28 are disposed at opposite positions. This can prevent the electromagnetic waves from interfering with each other during detection by the eddy current flaw detection sensor 26 and measurement by the eddy current displacement sensor 28.

  (9) The measuring head 13 includes a measuring head main body 29 and a spacer 30. The measuring head main body 29 is coupled to the rotary shaft 22 via the spacer 30, and the spacer 30 is a cylinder of the cylinder block 1 to be inspected. A plurality of types (for example, spacers 30 </ b> A and 30 </ b> B) are provided corresponding to the diameter of the inner peripheral surface 3. Accordingly, even when the diameter of the cylinder inner peripheral surface 3 of the cylinder block 1 to be inspected is different in a wide range (for example, when the diameter of the cylinder inner peripheral surface 3 is 90 mm, 60 mm, etc.), the same measuring head is used. Using the main body 29, these cylinder inner peripheral surfaces 3 can be accurately inspected for defects without increasing costs.

  (10) Since the position adjustment of the eddy current flaw detection sensor 26 with respect to the guide roller 27 is performed using a dedicated setting gauge 47 having a dial gauge 50, a gauge base 51, and a gauge master 52, the position adjustment is performed accurately and easily. Can be implemented.

  As mentioned above, although this invention was demonstrated based on the said embodiment, this invention is not limited to this. For example, in the present embodiment, the case where the displacement sensor for obtaining the change in the distance M between the sensor surface 36 of the eddy current flaw detection sensor 26 and the cylinder inner peripheral surface 3 is the eddy current displacement sensor 28 has been described. For example, a displacement sensor using a laser or an ultrasonic wave may be used.

1 Cylinder block (inspection object)
2 Cylinder bore 3 Cylinder inner peripheral surface 4 Peripheral portion 10 Cylinder inner peripheral surface defect inspection device (inner peripheral surface inspection device)
13 Measuring head 22 Rotating shaft 24 Frame 25 Moving base 26 Eddy current flaw detection sensor 26A Lower end 27 Guide roller 28 Eddy current displacement sensor 29 Measuring head body 30, 30A, 30B Spacer 36 Sensor surface 37 Tapered surface 41 Inlay portion (engaging portion)
44 Pin hole (positioning part)
46 Balance Weight 47 Setting Gauge 50 Dial Gauge 51 Gauge Base 52 Gauge Master 53 Gauge Mounting Bracket 54 Curved Concave 55 Curved Convex Surface 58 Probe M Distance S, SA, SB Dimensions

Claims (5)

A measuring head of an inner peripheral surface inspection device that is inserted into a bore of an object to be inspected, rotates in the circumferential direction of the inner peripheral surface facing the bore, and inspects the surface of the inner peripheral surface and internal defects,
It has a measuring head body equipped with a frame, a moving base, a flaw detection sensor , a guide roller and a displacement sensor ,
The moving base is provided to be movable in the diameter direction of the inner peripheral surface of the inspection object with respect to the frame.
The flaw detection sensor is attached to the moving base, the sensor surface is opposed to the inner peripheral surface of the object to be inspected, and the surface of the inner peripheral surface and internal defects are detected,
The guide rollers are attached to both sides of the flaw detection sensor in a plan view of the moving base and at the same height as the flaw detection sensor in a side view, and the inner circumference together with the moving base when the measuring head rotates. while moving the radially outer surface, Ru is configured to roll in pressed state to the inner circumferential surface,
The moving base is provided with a displacement sensor for determining a change in distance between the sensor surface of the flaw detection sensor and the inner peripheral surface of the object to be inspected on the same axis as the flaw detection sensor and opposite to the flaw detection sensor. A measuring head of an inner peripheral surface inspection apparatus characterized by the above. When the measuring head is inserted into the bore of the object to be inspected, the guide roller is brought into contact with the peripheral edge of the inner peripheral surface facing the bore, and the moving base is moved inward in the radial direction of the inner peripheral surface. The measuring head of the inner peripheral surface inspection apparatus according to claim 1, wherein a tapered surface is formed. The measuring head of the inner peripheral surface inspection apparatus according to claim 2, wherein the tapered surface of the guide roller is provided in a region below the lower end of the flaw detection sensor in a side view. 2. The measuring head of the inner peripheral surface inspection apparatus according to claim 1, wherein the object to be inspected is an engine cylinder or a cylinder block, and the inner peripheral surface is a cylinder inner peripheral surface. The measuring head of the inner peripheral surface inspection apparatus according to claim 1, wherein the flaw detection sensor is an eddy current flaw detection sensor and the displacement sensor is an eddy current displacement sensor .

Images