Straightness detection device for slender pipe parts
By designing a rotatable end clamping unit and an inner wall support structure, combined with limiting pins or strong magnets, the flexibility problem of multi-angle straightness detection for slender tube parts is solved, achieving high-precision detection stability and ensuring the accuracy of the outer surface of the parts.
Patent Information
- Application Number
- CN202520423234.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-11
- Publication Date
- 2026-03-06
- Estimated Expiration
- 2035-03-11
AI Technical Summary
Existing technologies struggle to determine the circumferential rotation angle of slender tubular parts during multi-angle straightness testing. Traditional testing methods lack flexibility and cannot meet the testing requirements of high-precision slender tubular parts.
A straightness detection device was designed, which adopts a rotatable end clamping unit and an inner wall support structure, combined with a limiting pin or a strong magnet to achieve multi-angle detection, and is supplemented by an auxiliary support structure to improve the flexibility and stability of the detection.
It achieves flexibility and accuracy in multi-angle straightness detection, ensuring the detection stability and external surface accuracy of high-precision slender tube parts, and reducing the risk of part deformation.
Smart Images
Figure CN223971555U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of testing device technology, specifically relating to a straightness testing device for slender tubular parts. Background Technology
[0002] Slender tubes are a special type of tubular part characterized by a large ratio between their axial length and radial diameter. This large axial and radial dimension makes it difficult to guarantee straightness during machining. Therefore, straightness inspection of slender tube parts is a crucial indicator for workpiece acceptance. Traditionally, the inspection of slender tube parts typically uses a dial indicator as the testing instrument, with a V-block as the support component. The dial indicator's contacts are placed against the outer surface of the slender tube, and the indicator is positioned along the length of the tube. While the device moves at a constant speed in the extension direction, the change in the dial indicator reading is observed to see if it is within the allowable error, thereby determining whether the slender tube parts meet the straightness requirements. For slender tube parts with high precision, circumferential multi-angle straightness testing is required during straightness testing. Traditional testing methods use V-blocks as support structures, which have relatively poor flexibility and make it difficult to determine the circumferential rotation angle of the slender tube parts during multi-angle straightness testing. Therefore, developing a straightness testing device that can determine the circumferential rotation angle of the slender tube parts during multi-angle straightness testing is very much in line with practical needs. Utility Model Content
[0003] In order to solve the problem in the prior art that it is difficult to determine the circumferential rotation angle of slender tube parts during multi-angle straightness testing, this utility model provides a straightness testing device for slender tube parts.
[0004] A straightness testing device for slender tubular parts includes a base plate, a support assembly, and a straightness testing assembly. The support assembly and the straightness testing assembly are both mounted on the top of the base plate, and the straightness testing assembly is arranged parallel to and opposite to the support assembly.
[0005] The support assembly includes a support slide and two end clamping units. The support slide is installed on the top of the base plate, and the length extension direction of the support slide is the same as the length extension direction of the base plate. The two end clamping units are arranged opposite to each other on the support slide, and each end clamping unit is slidably connected to the support slide. The clamping end of each end clamping unit can rotate circumferentially.
[0006] The straightness detection assembly includes a guide unit and a detection unit. The guide unit is installed on the top of the base plate and is arranged parallel to and opposite to the support slide. The detection unit is set on the guide unit and can reciprocate along the length extension direction of the guide unit. The detection end of the detection unit is set towards the support assembly.
[0007] Furthermore, the end clamping unit includes a first sliding seat, a first lifting cylinder, a fixed sleeve, a rotating shaft, a clamping head, and a screwing head. The first sliding seat is disposed on the support slide and is slidably connected to the support slide. The first lifting cylinder is disposed vertically on the top of the first sliding seat, and the bottom of the first lifting cylinder is fixedly connected to the top of the first sliding seat. The fixed sleeve is installed at the end of the piston rod in the first lifting cylinder, and the axis of the fixed sleeve is perpendicular to the axis of the first lifting cylinder. The rotating shaft is inserted into the fixed sleeve and is rotatably connected to the fixed sleeve. Both ends of the rotating shaft extend to the outside of the fixed sleeve. The clamping head is installed on the end of the rotating shaft near the other end clamping unit, and the screwing head is installed on the end of the rotating shaft away from the other end clamping unit.
[0008] Furthermore, the end clamping unit also includes a limiting pin. The top of the fixed sleeve is machined with an insertion hole, and multiple limiting holes are machined equidistantly along the circumferential direction on the outer circular surface of the rotating shaft. One end of the limiting pin is located outside the fixed sleeve, and the other end of the limiting pin passes through the insertion hole on the fixed sleeve and is inserted into a limiting hole on the rotating shaft. The fixed sleeve is locked and positioned with the rotating shaft by the limiting pin.
[0009] Furthermore, the support assembly also includes at least one auxiliary support unit, which is disposed between the two end clamping units and is disposed on the support slide and slidably connected to the support slide.
[0010] Furthermore, the auxiliary support unit includes a second sliding seat, a second lifting cylinder, a U-shaped seat, and two rubber support wheels. The second sliding seat is set on the support slide and is slidably connected to the support slide. The second lifting cylinder is set vertically on the top of the second sliding seat, and the bottom of the second lifting cylinder is fixedly connected to the top of the second lifting cylinder. The U-shaped seat is installed at the end of the piston rod in the second lifting cylinder. The two rubber support wheels are symmetrically arranged in the U-shaped seat along the center line of the width direction of the U-shaped seat, and the two ends of each rubber support wheel are respectively inserted into the two end walls of the U-shaped seat.
[0011] Furthermore, the detection unit includes a movable part, a sleeve, an L-shaped insert, a positioning sleeve, and a dial indicator. The movable part is mounted on the guide unit and can reciprocate along the length extension direction of the guide unit. The sleeve is mounted vertically on top of the movable part, and its bottom end is fixedly connected to the top end of the movable part. The vertical part of the L-shaped insert is inserted into the top of the sleeve and is movably connected to the sleeve. The L-shaped insert is locked and fixed to the sleeve by a first locking part. The positioning sleeve is mounted at the end of the horizontal part of the L-shaped insert and is fixedly connected to the L-shaped insert. The dial indicator is inserted into the positioning sleeve and is locked and fixed to the positioning sleeve by a second locking part. The contact end of the dial indicator passes through the positioning sleeve and extends downward to the outside of the positioning sleeve.
[0012] Furthermore, the guiding unit is a guide slide, and the moving part is a slide base;
[0013] Furthermore, the guide unit is a lead screw assembly, and the moving part is a screw sleeve;
[0014] The beneficial effects of this application compared to the prior art are:
[0015] 1. This application provides a straightness testing device for slender tubular parts. Compared with traditional straightness testing devices for tubular parts, it optimizes the support structure by replacing the traditional V-block with a clamping unit with a rotatable end, improving the rotational flexibility of the support structure. The rotation of the clamping unit is achieved by a rotating rod, a fixed sleeve, and bearings. Multiple limiting holes are equidistantly machined along the circumferential direction on the outer surface of the rotating rod. The deflection angle between adjacent limiting holes can be set to 15°, 20°, 30°, 45°, 60°, 90°, 120°, or 180°. One type of device allows for customization of the specific deflection angle based on actual work needs. A detachable limiting pin is also provided on the fixed sleeve. After the clamping unit rotates the workpiece to a fixed angle, the limiting pin can lock the current position, ensuring the stability of the workpiece during inspection. The cooperation between the limiting pin and the fixed deflection angle limiting hole facilitates the inspector in determining the rotation angle of the workpiece each time, enabling faster and more accurate alignment straightness and four-point straightness inspections (inspection is performed every 90° rotation of the workpiece).
[0016] 2. The straightness detection device for slender tube parts provided in this application optimizes the traditional support of the outer wall of slender tube parts to support the inner wall of slender tube parts. For high-precision slender tube parts, it can reduce the contact between the outer surface of the part and the support structure, which is conducive to ensuring the machining accuracy of the outer surface of the part.
[0017] 3. The straightness testing device for slender tubular parts provided in this application takes into account that some slender tubular parts are quite long, and using end clamping support can easily result in weak support in the middle, which can easily lead to bending deformation. Therefore, an auxiliary support structure is added to the testing device to provide temporary support for the middle of the slender tubular parts. The working position of the auxiliary support structure is adjustable, and it has good support adaptability and support flexibility. Attached Figure Description
[0018] Figure 1 This is a front view schematic diagram of the straightness detection device provided in this application (the guide unit is a lead screw assembly);
[0019] Figure 2 This is a front view schematic diagram of the support components in the straightness testing device provided in this application;
[0020] Figure 3This is a front view schematic diagram of the straightness detection component in the straightness detection device provided in this application;
[0021] Figure 4 This is a front view schematic diagram of the straightness detection device provided in this application (the guide unit is a guide slide):
[0022] Figure 5 This is a front view schematic diagram of the straightness detection component in the straightness detection device provided in this application;
[0023] Figure 6 This is a front view schematic diagram of the end clamping unit in the straightness detection device provided in this application;
[0024] Figure 7 A partial cross-sectional schematic diagram of the end clamping unit in the straightness testing device provided in this application;
[0025] Figure 8 This is a side view of the clamping head in the straightness testing device provided in this application;
[0026] Figure 9 This is a front view schematic diagram of the auxiliary support unit in the straightness detection device provided in this application;
[0027] Figure 10 This is a side view of the auxiliary support unit in the straightness testing device provided in this application;
[0028] Figure 11 This is a front view schematic diagram of the detection unit in the straightness detection device provided in this application;
[0029] Figure 12 This is a side view of the detection unit in the straightness detection device provided in this application;
[0030] Figure 13 A schematic diagram of the straightness testing device provided in this application (a slender tube with a small end diameter, the auxiliary support unit is not working).
[0031] Figure 14 A schematic diagram of the straightness testing device provided in this application (a slender tube with a large end diameter, with an auxiliary support unit in operation).
[0032] The diagram shows: 1. Base plate; 2. Support slide; 3. End clamping unit; 31. No. 1 sliding seat; 32. No. 1 lifting cylinder; 33. Fixed sleeve; 34. Rotating shaft; 35. Clamping head; 36. Tightening head; 37. Limiting pin; 38. Bearing; 39. Bearing cover; 310. No. 1 locking bolt; 331. Bearing limit ring; 4. Auxiliary support unit; 41. No. 2 sliding seat; 42. No. 2 lifting cylinder; 43. U-shaped seat; 44. Rubber support wheel; 5. Guide unit; 51. Motor; 52. Coupling; 53. Lead screw; 54. Bearing seat; 6. Detection unit; 61. Moving part; 62. Sleeve rod; 63. L-shaped insertion rod; 64. No. 1 locking part; 65. Positioning sleeve; 66. No. 2 locking part; 67. Dial indicator and the workpiece being measured. Detailed Implementation
[0033] Specific implementation method one: Combining Figures 1 to 8 , Figure 11 and Figure 12 This embodiment describes a straightness detection device including a base plate 1, a support assembly, and a straightness detection assembly. Both the support assembly and the straightness detection assembly are mounted on the top of the base plate 1, and the straightness detection assembly and the support assembly are arranged parallel to each other.
[0034] The support assembly includes a support slide 2 and two end clamping units 3. The support slide 2 is installed on the top of the base plate 1, and the length extension direction of the support slide 2 is the same as the length extension direction of the base plate 1. The two end clamping units 3 are arranged opposite to each other on the support slide 2, and each end clamping unit 3 is slidably connected to the support slide 2. The clamping end of each end clamping unit 3 can rotate circumferentially.
[0035] The straightness detection assembly includes a guide unit 5 and a detection unit 6. The guide unit 5 is installed on the top of the base plate 1 and is arranged parallel to and opposite to the support slide 2. The detection unit 6 is arranged on the guide unit 5 and can reciprocate along the length extension direction of the guide unit 5. The detection end of the detection unit 6 is set towards the support assembly.
[0036] The end clamping unit 3 includes a first sliding seat 31, a first lifting cylinder 32, a fixing sleeve 33, a rotating shaft 34, a clamping head 35, and a screwing head 36. The first sliding seat 31 is mounted on and slidably connected to the support slide 2. A threaded hole is machined on one side of the first sliding seat 31, and a first locking bolt 310 is inserted into the threaded hole. The screwing end of the first locking bolt 310 is located on the outside of the first sliding seat 31, and the threaded end of the first locking bolt 310 passes through the threaded hole on the first sliding seat 31 and contacts the side wall of the support slide 2. The first lifting cylinder 32 is vertically mounted on the top of the first sliding seat 31, and the bottom of the first lifting cylinder 32 is fixedly connected to the top of the first sliding seat 31. The fixing sleeve 33 is installed on the end of the piston rod in the first lifting cylinder 32. The axis of the fixed sleeve 33 is perpendicular to the axis of the first lifting cylinder 32. The rotating shaft 34 is inserted into the fixed sleeve 33 and rotatably connected to the fixed sleeve 33. The inner ring wall of the fixed sleeve 33 is provided with a bearing limiting ring 331. The bearing 38 is arranged on the side of the bearing limiting ring 331 near the screwing head 36. The outer ring of the bearing 38 is fitted with the inner wall of the fixed sleeve 33. A bearing cover 39 is fastened on the end of the fixed sleeve 33 near the screwing head 36. The bearing 38 is axially limited by the bearing cover 39 and the bearing limiting ring 331. Both ends of the rotating shaft 34 extend to the outside of the fixed sleeve 33. The clamping head 35 is installed on the end of the rotating shaft 34 near the other end clamping unit 3. The screwing head 36 is installed on the end of the rotating shaft 34 away from the other end clamping unit 3.
[0037] The end clamping unit 3 also includes a limiting pin 37. The top of the fixed sleeve 33 is machined with an insertion hole. Multiple limiting holes are machined at equal intervals along the circumference on the outer circular surface of the rotating shaft 34. One end of the limiting pin 37 is located outside the fixed sleeve 33, and the other end of the limiting pin 37 passes through the insertion hole on the fixed sleeve 33 and is inserted into a limiting hole on the rotating shaft 34. The fixed sleeve 33 is locked and positioned with the rotating shaft 34 by the limiting pin 37.
[0038] The detection unit 6 includes a movable part 61, a sleeve 62, an L-shaped insert 63, a positioning sleeve 65, and a dial indicator 67. The movable part 61 is mounted on the guide unit 5 and can reciprocate along the length extension direction of the guide unit 5. The sleeve 62 is mounted vertically on top of the movable part 61, and its bottom end is fixedly connected to the top end of the movable part 61. The vertical part of the L-shaped insert 63 is inserted into the top of the sleeve 62 and is movably connected to the sleeve 62. The L-shaped insert 63 is locked and fixed to the sleeve 62 by a first locking part 64. The positioning sleeve 65 is mounted on the end of the horizontal part of the L-shaped insert 63 and is fixedly connected to the L-shaped insert 63. The dial indicator 67 is inserted into the positioning sleeve 65 and is locked and fixed to the positioning sleeve 65 by a second locking part 66. The contact end of the dial indicator 67 passes through the positioning sleeve 65 and extends downward to the outside of the positioning sleeve 65.
[0039] In this embodiment, the end clamping unit 3 is used to clamp and fix the ends of tubular parts. Unlike existing end clamping structures, this application uses internal wall support. The clamping head 35 is made of multiple support discs of different diameters stacked concentrically. During use, a rubber sleeve is fitted on each support disc. The rubber sleeve contacts the inner wall of the pipe and is fixed by friction to facilitate stability and accuracy during rotation. The rotation is achieved by the screwing head 36. When multi-angle straightness measurement is required, the limiting pin 37 must first be pulled out of the fixing sleeve 33 to ensure that the rotating shaft 34 can rotate freely in the fixing sleeve. A scale can be provided circumferentially on the end of the fixing sleeve 33 near the mounting end of the screwing head 36. The rotating head 36 is used to guide the operator to rotate it to the target angle. Once the rotating head 36 is rotated to the target angle, the limiting pin 37 is reinserted to lock the rotating shaft 34 and the fixed sleeve 33, ensuring the accuracy of the position of the rotating shaft 34 during testing. However, the design of the limiting pin 37 has certain limitations and can only test some fixed angles. If the range of testing angles is to be expanded, the limiting pin 37 can be replaced with a strong magnet. At the same time, an annular groove is machined at the corresponding position of the rotating shaft 34, and a magnetic ring that cooperates with the strong magnet is arranged at the bottom of the groove. The bottom of the strong magnet is machined into an arc surface to better cooperate with the magnetic ring. The working angle of the rotating shaft 34 is determined by magnetic attraction.
[0040] The detection unit 6 uses an L-shaped insert rod 63 and a sleeve rod 62 as a support structure for the dial indicator, which allows for longitudinal adjustment of the measuring part of the dial indicator 67. This facilitates the detection of pipe parts of different diameters and improves the flexibility of the detection. The first locking part 64 and the second locking part 66 are both locked with locking bolts. The clamping force provided by the locking bolts ensures that the sleeve rod 62, the L-shaped insert rod 63, the positioning sleeve 65, and the dial indicator 67 are all securely connected.
[0041] Specific Implementation Method Two: Combining Figures 1 to 3 This embodiment differs from specific embodiment one in that the guide unit 5 is a lead screw assembly and the movable part 61 is a threaded sleeve. Other components and connection methods are the same as in specific embodiment one.
[0042] In this embodiment, the guide unit 5 includes a motor 51, a coupling 52, a lead screw 53, and two bearing seats 54. The lead screw 53 is fixed to the base plate 1 through the two bearing seats 54, and the lead screw 53 and the two bearing seats 54 are rotatably connected by bearings. Both ends of the lead screw 53 extend to the outside of the two bearing seats 54, and one end of the lead screw 53 is connected to the power output shaft of the motor 51 through the coupling 52. The motor 51 is used to drive the lead screw 53 to rotate. The movable part 61 is fitted on the lead screw 53 and threadedly connected to the lead screw 53. The use of a lead screw and nut drive to drive the detection unit 6 to move along the length of the pipe being tested can ensure the uniformity and accuracy of the movement. For single-person testing, it can free the hands of the testing personnel and facilitate the recording of data.
[0043] Specific implementation method three: Combining Figures 4 to 5 This embodiment differs from Specific Embodiment 1 in that the guide unit 5 is a guide slide, and the movable part 61 is a slide seat. Other components and connections are the same as in Specific Embodiment 1.
[0044] In this embodiment, the guide unit 5 is a guide slide. Unlike the technical solution in the second embodiment, the movement of the detection unit 6 in this embodiment needs to be done manually. Although it is difficult to guarantee the uniformity of the movement, it is simple to operate, convenient and relatively inexpensive to manufacture. In practical applications, the detection personnel can choose the configuration according to their needs.
[0045] Specific implementation method four: Combining Figures 9 to 10 This embodiment differs from Specific Embodiment Three in that the support assembly further includes at least one auxiliary support unit 4, which is disposed between the two end clamping units 3 and is slidably connected to the support slide 2.
[0046] The auxiliary support unit 4 includes a second sliding seat 41, a second lifting cylinder 42, a U-shaped seat 43, and two rubber support wheels 44. The second sliding seat 41 is mounted on the support slide 2 and is slidably connected to the support slide 2. A threaded hole is machined on one side of the second sliding seat 41, and a second locking bolt is inserted into the threaded hole. The screwing end of the second locking bolt is located on the outside of the second sliding seat 41, and the threaded end of the second locking bolt passes through the threaded hole on the second sliding seat 41 and contacts the side wall of the support slide 2. The second lifting cylinder 42 is mounted vertically on the top of the second sliding seat 41, and the bottom of the second lifting cylinder 42 is fixedly connected to the top of the second lifting cylinder 42. The U-shaped seat 43 is installed at the end of the piston rod in the second lifting cylinder 42. The two rubber support wheels 44 are symmetrically arranged in the U-shaped seat 43 along the center line of the width direction of the U-shaped seat 43, and the two ends of each rubber support wheel 44 are respectively inserted into the two end walls of the U-shaped seat 43. Other components and connection methods are the same as in Specific Implementation Method 3.
[0047] The number of auxiliary support units 4 provided in this embodiment is determined according to the length of the slender tube, generally 1 to 2. The second lifting cylinder 42 is used to adjust the working height of the U-shaped seat 43 to adapt to the test parts with different tube diameters. The rubber support wheel 44 in the U-shaped seat 43 is used to contact the test part without causing rigid compression on the surface of the test part, which is beneficial to ensuring the surface roughness of the test part. In addition to being used for auxiliary support, it can also be used for temporary support of the part when clamping the part. When clamping the part, the middle part of the test part is first placed on the auxiliary support unit 4 for pre-positioning. One end clamping unit 3 is first connected to one end of the test part to ensure reliable support at one end. Then, the other end clamping unit 3 is connected to the other end of the test part to ensure the clamping accuracy of the test part.
[0048] The present invention has been disclosed above with reference to preferred embodiments, but it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed structure and technical content to create equivalent embodiments without departing from the scope of the present invention. However, any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.
[0049] Working principle:
[0050] The straightness testing device for slender tubular parts provided in this application is first assembled with all components in place. The part to be tested is placed on the auxiliary support unit 4 for temporary support. Simultaneously, the working height of the end clamping unit 3 is adjusted so that the axis of the clamping head is collinear with the axis of the part to be tested. One end clamping unit 3 is moved and inserted into one end of the part to be tested. After the connection is stable, the other end clamping unit 3 is moved and inserted into the other end of the part to be tested. After the connection is stable, the part to be tested is clamped. Based on the structural characteristics of the part to be tested, the testing personnel consider whether further... During the testing process, auxiliary support unit 4 is used for auxiliary support. After the part to be tested is fixed, the working height of the testing unit 6 is adjusted. After the dial indicator 67 changes its reading with the surface of the workpiece, it returns to zero and is set to the initial position. After the dial indicator 67 is adjusted, the testing unit 6 is controlled to move along the axis of the workpiece. Here, taking the guide unit 5 as the structure of the lead screw assembly as an example, the motor 51 is started to drive the lead screw 53 to rotate. The moving part 61 drives the testing unit 6 to move along the length of the lead screw 53. The straightness test is completed with the movement of the testing unit 6.
[0051] If multi-point testing is required, taking alignment straightness testing as an example, firstly, the limiting pin 37 needs to be pulled out of the fixed sleeve 33 to ensure that the rotating shaft 34 can rotate freely in the fixed sleeve. The fixed sleeve 33 can be provided with a scale along the circumferential direction at the end near the installation of the screw head 36 to indicate the rotation angle of the screw head 36 to the testing personnel. When the screw head 36 rotates to the target angle (the rotation angle for alignment straightness testing is 180°), the limiting pin 37 is reinserted to lock the rotating shaft 34 and the fixed sleeve 33 to ensure the accuracy of the position of the rotating shaft 34 during testing. At this time, the control unit 6 moves along the axial extension direction of the workpiece being tested, and the changes in the reading of the dial indicator 67 are observed and recorded to complete the alignment straightness testing of slender tubular parts.
Claims
1. An apparatus for detecting straightness of an elongated tubular part, characterized by: The straightness detection device comprises a base plate (1), a supporting assembly and a straightness detection assembly, the supporting assembly and the straightness detection assembly are both installed on the top of the base plate (1), and the straightness detection assembly is arranged in parallel with the supporting assembly. The supporting assembly comprises a supporting slide (2) and two end clamping units (3), the supporting slide (2) is installed on the top of the base plate (1), and the length extension direction of the supporting slide (2) is the same as that of the base plate (1), the two end clamping units (3) are arranged on the supporting slide (2) in opposition, and each end clamping unit (3) is in sliding connection with the supporting slide (2), and the clamping end of each end clamping unit (3) can rotate circumferentially. The straightness detection assembly comprises a guide unit (5) and a detection unit (6), the guide unit (5) is installed on the top of the base plate (1), and the guide unit (5) is arranged in parallel with the supporting slide (2), the detection unit (6) is arranged on the guide unit (5), and the detection unit (6) can reciprocate along the length extension direction of the guide unit (5), and the detection end of the detection unit (6) is arranged towards the supporting assembly.
2. The straightness detecting device for an elongated pipe member according to claim 1, wherein: The end clamping unit (3) comprises a No. 1 sliding seat (31), a No. 1 lifting cylinder (32), a fixed sleeve (33), a rotating shaft (34), a clamping head (35) and a screw head (36), the No. 1 sliding seat (31) is arranged on the supporting slide (2) and in sliding connection with the supporting slide (2), the No. 1 lifting cylinder (32) is arranged in a vertical direction on the top of the No. 1 sliding seat (31), and the bottom of the No. 1 lifting cylinder (32) is fixedly connected with the top of the No. 1 sliding seat (31), the fixed sleeve (33) is installed on the end of the piston rod in the No. 1 lifting cylinder (32), and the axis of the fixed sleeve (33) is arranged perpendicularly to the axis of the No. 1 lifting cylinder (32), the rotating shaft (34) is inserted in the fixed sleeve (33) and in rotational connection with the fixed sleeve (33), the two ends of the rotating shaft (34) both extend to the outside of the fixed sleeve (33), the clamping head (35) is installed on one end of the rotating shaft (34) close to the other end clamping unit (3), and the screw head (36) is installed on one end of the rotating shaft (34) away from the other end clamping unit (3).
3. The straightness detecting device for an elongated pipe member according to claim 2, wherein: The end clamping unit (3) further comprises a limiting pin (37), the top of the fixed sleeve (33) is processed with a insertion hole, a plurality of limiting holes are processed equidistantly on the outer circular surface of the rotating shaft (34) in a circumferential direction, one end of the limiting pin (37) is arranged outside the fixed sleeve (33), the other end of the limiting pin (37) passes through the insertion hole on the fixed sleeve (33) and is inserted in one limiting hole on the rotating shaft (34), and the fixed sleeve (33) is locked and positioned with the rotating shaft (34) through the limiting pin (37).
4. The straightness detecting apparatus for an elongated pipe member according to claim 3, wherein: The supporting assembly further comprises at least one auxiliary supporting unit (4), the auxiliary supporting unit (4) is arranged between the two end clamping units (3), and the auxiliary supporting unit (4) is arranged on the supporting slide (2) and in sliding connection with the supporting slide (2).
5. The straightness detecting apparatus for an elongated pipe member according to claim 4, wherein: The auxiliary supporting unit (4) comprises a second sliding seat (41), a second lifting cylinder (42), a U-shaped seat (43) and two rubber supporting wheels (44), the second sliding seat (41) is arranged on the supporting slide (2) and is in sliding connection with the supporting slide (2), the second lifting cylinder (42) is arranged on the top of the second sliding seat (41) in the vertical direction, the bottom of the second lifting cylinder (42) is fixedly connected with the top of the second lifting cylinder (42), the U-shaped seat (43) is installed on the end of the piston rod of the second lifting cylinder (42), the two rubber supporting wheels (44) are symmetrically arranged in the U-shaped seat (43) along the center line of the width direction of the U-shaped seat (43), and the two ends of each rubber supporting wheel (44) are respectively inserted into the two end walls of the U-shaped seat (43).
6. The straightness detecting device for an elongated pipe member according to claim 1, wherein: The detection unit (6) comprises a movable part (61), a sleeve rod (62), an L-shaped plug rod (63), a positioning sleeve (65) and a dial gauge (67), the movable part (61) is arranged on the guide unit (5), and the movable part (61) can reciprocate along the length extension direction of the guide unit (5), the sleeve rod (62) is arranged on the top of the movable part (61) in the vertical direction, and the bottom end of the sleeve rod (62) is fixedly connected with the top end of the movable part (61), the vertical part of the L-shaped plug rod (63) is inserted into the top of the sleeve rod (62) and is movably connected with the sleeve rod (62), the L-shaped plug rod (63) is locked and fixed with the sleeve rod (62) through a first locking part (64), the positioning sleeve (65) is arranged at the end of the horizontal part of the L-shaped plug rod (63) and is fixedly connected with the L-shaped plug rod (63), the dial gauge (67) is inserted into the positioning sleeve (65), and the dial gauge (67) is locked and fixed with the positioning sleeve (65) through a second locking part (66), the contact end of the dial gauge (67) extends downward to the outside of the positioning sleeve (65) through the positioning sleeve (65).
7. The straightness detecting apparatus for an elongated pipe member according to claim 6, wherein: The guide unit (5) is a guide slide, and the movable part (61) is a slide seat.
8. The straightness detecting apparatus for an elongated pipe member according to claim 6, wherein: The guide unit (5) is a lead screw assembly, and the movable part (61) is a screw sleeve.