Measuring tape calibration table device and calibration method thereof

Abstract

The invention discloses a measuring tape verification table device, belongs to the technical field of detection, and solves the problem that the position of a clamping point of an existing verification table cannot be adjusted, so that observation is affected. The device comprises a main working table, a working tail table and a heavy weight, the clamping structure comprises a mounting plate, two sliding plates and two first extrusion screw rods, two L-shaped plates are mounted on the mounting plate, one ends of the two sliding plates are slidably mounted on the inner sides of the two L-shaped plates in a one-to-one correspondence manner, an adjusting screw rod is rotatably mounted on each L-shaped plate, and the two first extrusion screw rods are rotatably mounted on the working tail table. One end of each adjusting screw rod penetrates through the corresponding sliding plate and is in threaded connection with the sliding plate, guide grooves are formed in the opposite ends of the two sliding plates, and the two first extrusion screw rods are in threaded connection to the other ends of the sliding plates in a one-to-one correspondence mode. According to the measuring tape verification table device, the position of a clamping point can be adjusted at any time, so that detection by a worker is facilitated. The invention further discloses a measuring tape verification method, and the zero value error and the indication error of the steel measuring tape are detected.

Description

Technical Field

[0001] The present invention relates to the field of detection technology, and more specifically, to a tape measure calibration platform device and a calibration method thereof. Background Art

[0002] Steel tape measure is a measuring tool used to measure the length of an object. It is widely used in various enterprises, especially in the shipbuilding process, where steel tape measure is often used for various measurements. In order to ensure that the value of the steel tape measure is accurate and reliable, the newly imported steel tape measure generally needs to be tested when it is issued and used. The traditional detection method is to manually hold the standard steel tape measure and the steel tape measure to be tested, hook a measuring object, and then check the scale lines one by one. This method has high labor intensity and inconvenient detection. In the prior art, there are some tape measure calibration platforms that can be used for auxiliary detection, such as the existing calibration platforms with patent publication numbers: CN207019561U, CN210952565U, etc., which can greatly facilitate the detection of staff. However, in actual use, the clamping point positions corresponding to the standard steel tape measure and the steel tape measure to be tested are fixed. When the clamping points of the standard steel tape measure or the steel tape measure to be tested are fixed, it is easy to block the scale line value that needs to be observed, thereby causing the problem of being unable to observe and detect.

[0003] Therefore, it is urgent to develop and design a tape measure calibration platform device and a calibration method thereof to solve the above-mentioned problems. Summary of the invention

[0004] The technical problem to be solved by the present invention is to address the above-mentioned deficiencies in the prior art. One purpose of the present invention is to provide a tape measure calibration platform device, which can adjust the position of the clamping point at any time to facilitate detection by staff.

[0005] The second purpose of the present invention is to provide a tape measure calibration method to detect the zero value error and indication error of the steel tape measure.

[0006] In order to achieve the above-mentioned purpose one, the present invention provides a tape measure calibration platform device, including a main workbench, a work tail platform and a weight, the main workbench and the work tail platform are detachably connected, and the main workbench is provided with a positioning structure for positioning the steel tape measure and a clamping structure for clamping the scale bar of the steel tape measure in sequence at one end of the main workbench along the work tail platform, and a movable clamping assembly for connecting with the scale bar of the steel tape measure is hung on the top of the weight; the clamping structure includes a mounting plate, two sliding plates and two first extrusion screws, the mounting plate is detachably mounted on the main workbench, and two L-shaped plates are mounted on the mounting plate, one end of the two sliding plates is slidably mounted on the inner side of the two L-shaped plates in a one-to-one manner, and an adjusting screw is rotatably mounted on each of the L-shaped plates, one end of the adjusting screw passes through the sliding plate and is threadedly connected to the sliding plate, and a guide groove is provided at the opposite end of the two sliding plates, and the two first extrusion screws are threadedly connected to the other end of the sliding plate in a one-to-one manner, and the end of each of the first extrusion screws extends into the guide groove.

[0007] As a further improvement, the positioning structure includes a standard steel tape measure positioning assembly and a steel tape measure positioning assembly to be tested. The standard steel tape measure positioning assembly and the steel tape measure positioning assembly to be tested have the same structure and both include three columns. The three columns are evenly fixed on the top of the main workbench and form a accommodating cavity for accommodating the steel tape measure.

[0008] Furthermore, the movable clamp assembly includes a U-shaped seat and two second extrusion screws, the two second extrusion screws are threadedly connected to the U-shaped seat, and the end of each second extrusion screw extends into the U-shaped seat. A hook is provided at the bottom of the U-shaped seat, and the weight is suspended on the hook.

[0009] Furthermore, the ends of the first extrusion screw and the second extrusion screw are both provided with spherical rubber heads, and the inner wall bottoms of the guide groove and the U-shaped seat are both provided with rubber pads.

[0010] Furthermore, one end of the adjusting screw away from the sliding plate and the top of the first extrusion screw and the top of the second extrusion screw are all movably connected with radially arranged handles.

[0011] Furthermore, a white silicone plate is provided on the top surface of the working tail table, and a rounded corner is provided at one end of the white silicone plate away from the main working table.

[0012] Furthermore, the main workbench and the work tail platform, and the mounting plate and the main workbench are connected by a plurality of fastening bolts.

[0013] Furthermore, a cylindrical pin is provided in the middle of one end of the working tail table away from the main working table, and a slide groove arranged along its axial direction is provided in the middle of one end of the working tail table away from the main working table, and the cylindrical pin is slidably installed in the slide groove.

[0014] In order to achieve the above-mentioned second objective, the present invention provides a tape measure calibration method, including the above-mentioned tape measure calibration platform device, the method includes zero value error detection and indication error detection, and the specific steps are as follows:

[0015] S1: Place the standard steel tape measure into the accommodation cavity between the three upright posts of the standard steel tape measure positioning assembly corresponding to the positioning structure;

[0016] S2: Pull the corresponding ruler of the standard steel tape measure to extend, so that the ruler passes through the guide groove corresponding to one of the sliding plates, with the front of the scale line facing upwards, and the back of the scale line flatly attached to the top surface of the work tail table, until it extends to the end of the work tail table away from the main workbench, and hooks the bottom surface of the U-shaped seat corresponding to the movable clamp assembly;

[0017] S3: Hang the weight on the hook corresponding to the movable clamp assembly, and then use one of the second squeezing screws corresponding to the movable clamp assembly to squeeze and fix the end of the standard steel tape measure, and use the first squeezing screw above one of the sliding plates to squeeze and fix the other end of the standard steel tape measure;

[0018] S4: placing the steel tape measure to be tested into the accommodation cavity between the three upright posts of the steel tape measure positioning assembly to be tested corresponding to the positioning structure;

[0019] S5: Pull the rack corresponding to the steel tape measure to be tested to extend, so that the tape passes through the guide groove corresponding to the other sliding plate, with the front of the scale line facing upwards, and the back of the scale line flatly fits on the top surface of the work tail table, until it extends to the end of the work tail table away from the main workbench, and hooks the bottom surface of the U-shaped seat corresponding to the movable clamp assembly;

[0020] S6: Using another second squeezing screw corresponding to the movable clamp assembly to squeeze and fix the end of the steel tape measure to be tested, and using the first squeezing screw above another sliding plate to squeeze and fix the other end of the steel tape measure to be tested;

[0021] S7: Read the error value between the steel tape measure to be tested at the 500mm scale line position and the standard steel tape measure at the 500mm scale line position, regard it as zero value error, and record it;

[0022] S8: Compare the steel tape measure to be tested with the standard steel tape measure at each meter scale line position, and calculate the indication error of each inspected point of the steel tape measure to be tested and record it. If the zero value error is within the standard range, and the indication error of each inspected point is within the standard range, the steel tape measure to be tested is qualified, otherwise it is unqualified.

[0023] Furthermore, in step S8, the indication error of each inspected point of the steel tape to be inspected is calculated according to the following formula:

[0024] △L=L-(LS20+δL)

[0025] Where:

[0026] △L—the indication error of the steel tape measure receiving point to be tested,

[0027] L—nominal length of the inspection point of the steel tape to be tested,

[0028] LS20 - the actual length of a standard steel tape at a temperature of 20°C.

[0029] δL—The deviation value of the inspected point of the steel tape to be tested read on the standard steel tape.

[0030] Beneficial Effects

[0031] Compared with the prior art, the present invention has the following advantages:

[0032] The tape measure calibration platform device of the present invention has a first extrusion screw installed on a slidable sliding plate. In actual use, the sliding plate can be driven to move by rotating the adjusting screw, and then the position of the first extrusion screw can be adjusted, so that the first extrusion screw can be clamped and fixed at a position avoiding the scale line that needs to be observed. For example, when detecting the indication error, the first extrusion screw can be clamped and fixed at a position avoiding the scale line position of 4 meters or 5 meters. The tape measure calibration platform device can adjust the position of the clamping point at any time, thereby facilitating detection by staff. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a schematic diagram of the top view structure of the present invention;

[0034] Figure 2 It is an enlarged schematic diagram of the top view structure of the main working table in the present invention;

[0035] Figure 3 for Figure 1 A schematic diagram of the structure enlargement at the center A;

[0036] Figure 4 It is a schematic diagram of the main structure of the present invention;

[0037] Figure 5 for Figure 4 A schematic diagram of the structure enlarged at B in the middle;

[0038] Figure 6 for Figure 4 Enlarged schematic diagram of the structure at C in the middle.

[0039] Among them: 1-main workbench, 2-work tail platform, 3-weight, 4-ruler, 5-movable clamp assembly, 6-mounting plate, 7-sliding plate, 8-first extrusion screw, 9-L-shaped plate, 10-adjusting screw, 11-guide groove, 12-column, 13-rubber head, 14-rubber pad, 15-handle, 16-white silicone plate, 17-fastening bolt, 18-cylindrical pin, 19-slide, 20-standard steel tape measure, 21-steel tape measure to be tested, 51-U-shaped seat, 52-second extrusion screw, 53-hook. DETAILED DESCRIPTION

[0040] The present invention will be further described below with reference to the specific embodiments in the accompanying drawings.

[0041] See also Figure 1-6 A tape measure calibration platform device of the present invention comprises a main workbench 1, a work tail platform 2 and a weight 3, wherein the main workbench 1 and the work tail platform 2 are detachably connected to facilitate disassembly and movement, and a positioning structure for positioning a steel tape measure and a clamping structure for clamping a scale bar 4 of the steel tape measure are sequentially arranged along one end of the work tail platform 2 on the main workbench 1, and a movable clamping assembly 5 for connecting with the scale bar 4 of the steel tape measure is hung on the top of the weight 3, so as to realize the use of the weight 3 to straighten and flatten the scale bar of the steel tape measure; specifically, the clamping structure comprises a mounting plate 6, two sliding plates 7 and two first extrusion screws 8, wherein the mounting plate 6 is detachably mounted on the main workbench 1, which is convenient for disassembly and maintenance, and a first extrusion screw 8 is mounted on the mounting plate 6 Two L-shaped plates 9 are installed, and one end of the two sliding plates 7 is slidably installed on the inner side of the two L-shaped plates 9 in a one-to-one manner, which plays a guiding role in the sliding of the sliding plates 7. An adjusting screw 10 is rotatably installed on each L-shaped plate 9, and one end of the adjusting screw 10 passes through the sliding plate 7 and is threadedly connected thereto, so that the position of the sliding plate 7 can be adjusted by using the adjusting screw 10. Guide grooves 11 are provided at opposite ends of the two sliding plates 7 to facilitate the insertion of the steel tape measure 4 into the sliding plate 7, and then to facilitate the first extrusion screw 8 to extrude and fix the scale bar 4. The two first extrusion screws 8 are threadedly connected to the other end of the sliding plate 7 in a one-to-one manner, and the end of each first extrusion screw 8 extends into the guide groove 11.

[0042] The tape measure calibration platform device of the present invention has a first extrusion screw 8 installed on a slidable sliding plate 7. In actual use, the sliding plate 7 can be driven to move by rotating the adjusting screw 10, and then the position of the first extrusion screw 8 can be adjusted, so that the first extrusion screw 8 can be clamped and fixed at a position avoiding the scale line that needs to be observed. For example, when detecting the indication error, the tape measure calibration platform device can adjust the position of the clamping point at any time, thereby facilitating detection by the staff.

[0043] Preferably, the positioning structure includes a standard steel tape measure positioning assembly and a steel tape measure positioning assembly to be tested. The standard steel tape measure positioning assembly and the steel tape measure positioning assembly to be tested have the same structure and both include three columns 12. The three columns 12 are evenly fixed on the top of the main workbench 1 and form a accommodating cavity for accommodating the steel tape measure. The standard steel tape measure 20 and the steel tape measure 21 to be tested are both placed in the accommodating cavity, which can facilitate the staff to pull the ruler 4 out, making the operation more convenient.

[0044] Preferably, the movable clamp assembly 5 includes a U-shaped seat 51 and two second extrusion screws 52, wherein the two second extrusion screws 52 are threadedly connected to the U-shaped seat 51, and the end of each second extrusion screw 52 extends into the U-shaped seat 51, and a hook 53 is provided at the bottom of the U-shaped seat 51, and the weight 3 is suspended on the hook 53. The movable clamp assembly 5 adopts the cooperation of the U-shaped seat 51 and the second extrusion screw 52, ​​which facilitates the insertion of the steel tape measure 4 into the U-shaped seat 51, and also facilitates the end of the tape 4 to hook the bottom surface of the U-shaped seat 51.

[0045] Preferably, a spherical rubber head 13 is provided at the end of the first extrusion screw 8 and the second extrusion screw 52, ​​and a rubber pad 14 is provided at the bottom of the inner wall of the guide groove 11 and the U-shaped seat 51. The rubber head 13 and the rubber pad 14 are in contact with the ruler 4 to avoid the problem of wear of the ruler 4 due to rigid friction.

[0046] Preferably, radially arranged handles 15 are movably inserted at the end of the adjusting screw 10 away from the sliding plate 7 and the top of the first extrusion screw 8 and the top of the second extrusion screw 52 to facilitate the rotation of the adjusting screw 10, the first extrusion screw 8, and the second extrusion screw 52.

[0047] Preferably, the top surface height of the working tail platform 2 is higher than the top surface height of the main working platform 1, so that the ruler 4 can better fit on the top surface of the working tail platform 2. A white silicone plate 16 is also provided on the top surface of the working tail platform 2. The white silicone plate 16 allows the staff to better observe the position of the scale line. A chamfer is provided on the end of the white silicone plate 16 away from the main working platform 1, so that the ruler 4 can be better bent under the gravity tension of the weight 3, thereby effectively protecting the ruler 4.

[0048] Preferably, the main workbench 1 and the work tail platform 2, and the mounting plate 6 and the main workbench 1 are connected by a plurality of fastening bolts 17 to achieve a detachable connection.

[0049] Preferably, a cylindrical pin 18 is provided at the middle position of the end of the work tail table 2 away from the main work table 1, and a slide groove 19 arranged along its axial direction is also provided at the middle position of the end of the work tail table 2 away from the main work table 1. The cylindrical pin 18 is slidably installed in the slide groove 19, and a step surface is provided at the lower part of the cylindrical pin 18. The step surface is used to fit the top surface of the slide groove 19, so that the cylindrical pin 18 can move axially along the work tail table 2 and can also rotate. In the actual working process, the cylindrical pin 18 can separate and position the scale bars 4 of the two steel tape measures to avoid the problem of the scale bars 4 being offset and affecting the observation and detection. At the same time, the movable cylindrical pin 18 can avoid the position of the scale line that needs to be observed, so as not to affect the staff's observation of the scale value of the inspected point. At the same time, the movable cylindrical pin 18 can also guide the scale bar 4 to avoid the problem of damage caused by the rigid friction between the edge of the scale bar 4 and the cylindrical pin 18.

[0050] A tape measure calibration method includes the above-mentioned tape measure calibration platform device. The method includes zero value error detection and indication error detection. The specific steps are as follows:

[0051] S1: placing the standard steel tape measure 20 into the accommodation cavity between the three upright posts 12 of the standard steel tape measure positioning assembly corresponding to the positioning structure, so as to realize the positioning of the standard steel tape measure 20;

[0052] S2: Pull the ruler 4 corresponding to the standard steel tape measure 20 to extend, so that the ruler 4 passes through the guide groove 11 corresponding to one of the sliding plates 7, with the front of the scale line facing upwards, and the back of the scale line flatly attached to the top surface of the work tail table 2, so as to facilitate observation of the scale value, until it extends to the end of the work tail table 2 away from the main workbench 1, and hooks the bottom surface of the U-shaped seat 51 corresponding to the movable clamp assembly 5;

[0053] S3: Hang the weight 3 on the hook 53 corresponding to the movable clamp assembly 5, and then use one of the second squeezing screws 52 corresponding to the movable clamp assembly 5 to squeeze and fix the end of the ruler 4 of the standard steel tape measure 20, and use the first squeezing screw 8 above one of the sliding plates 7 to squeeze and fix the other end of the ruler 4 of the standard steel tape measure 20, so as to clamp and fix the ruler 4 of the standard steel tape measure 20;

[0054] S4: placing the steel tape measure 21 to be detected into the accommodation cavity between the three upright posts 12 of the steel tape measure positioning assembly to be detected corresponding to the positioning structure, so as to locate the position of the steel tape measure 21 to be detected;

[0055] S5: Pull the rack 4 corresponding to the steel tape measure 21 to be tested to extend, so that the tape measure 4 passes through the guide groove 11 corresponding to the other sliding plate 7, with the front of the scale line facing upward, and the back of the scale line flatly attached to the top surface of the working tail table 2, so as to facilitate observation of the scale value, until it extends to the end of the working tail table 2 away from the main working table 1, and hooks the bottom surface of the U-shaped seat 51 corresponding to the movable clamp assembly 5;

[0056] S6: Use another second squeezing screw 52 corresponding to the movable clamp assembly 5 to squeeze and fix the end of the scale bar 4 of the steel tape measure 21 to be tested, and use the first squeezing screw 8 above the other sliding plate 7 to squeeze and fix the other end of the scale bar 4 of the steel tape measure 21 to be tested, so as to clamp and fix the scale bar 4 of the standard steel tape measure 20;

[0057] S7: Read the error value between the steel tape measure 21 to be tested at the 500mm scale line position and the standard steel tape measure 20 at the 500mm scale line position, regard it as a zero value error, and record it, so as to realize the zero value error detection of the steel tape measure 21 to be tested;

[0058] S8: Compare the steel tape measure 21 to be tested with the standard steel tape measure 20 at each meter scale line position, and calculate the indication error of each inspected point of the steel tape measure 21 to be tested, and record it to realize the indication error detection of the steel tape measure 21 to be tested. If the zero value error is within the standard range, and the indication error of each inspected point is within the standard range, the steel tape measure to be tested is qualified, otherwise, it is unqualified.

[0059] Among them, in step S8, the indication error of each inspected point of the steel tape measure 21 to be inspected is calculated according to the following formula:

[0060] △L=L-LS20+δL

[0061] Where:

[0062] △L—the indication error of the steel tape measure receiving point to be tested,

[0063] L—nominal length of the inspection point of the steel tape to be tested,

[0064] LS20 - actual length of standard steel tape at 20°C.

[0065] δL—The deviation value of the test point of the steel tape to be tested read on the standard steel tape.

[0066] By using the above-mentioned verification method, it is possible to detect the zero value error and indication error of the steel tape measure, thereby effectively improving the detection accuracy.

[0067] The above are only preferred embodiments of the present invention. It should be pointed out that for those skilled in the art, several modifications and improvements can be made without departing from the structure of the present invention, which will not affect the effect of the implementation of the present invention and the practicality of the patent.

Claims

1. A tape measure calibration platform device, characterized in that: The invention comprises a main working table (1), a working tail table (2) and a weight (3), wherein the main working table (1) and the working tail table (2) are detachably connected, a positioning structure for positioning a steel tape measure and a clamping structure for clamping a scale bar (4) of the steel tape measure are arranged on the main working table (1) along one end of the working tail table (2), and a movable clamping assembly (5) for connecting with the scale bar (4) of the steel tape measure is hung on the top of the weight (3); the clamping structure comprises a mounting plate (6), two sliding plates (7) and two first extrusion screws (8), and the mounting plate (6) is detachably mounted on the main working table (1) Two L-shaped plates (9) are installed on the mounting plate (6), one end of the two sliding plates (7) is slidably installed on the inner side of the two L-shaped plates (9) in a one-to-one manner, and an adjusting screw (10) is rotatably installed on each of the L-shaped plates (9), one end of the adjusting screw (10) passes through the sliding plate (7) and is threadedly connected thereto, and a guide groove (11) is provided at the opposite ends of the two sliding plates (7), and the two first extrusion screws (8) are threadedly connected to the other end of the sliding plate (7) in a one-to-one manner, and the end of each of the first extrusion screws (8) extends into the guide groove (11).

2. A tape measure calibration platform device according to claim 1, characterized in that: The positioning structure comprises a standard steel tape measure positioning component and a steel tape measure positioning component to be tested. The standard steel tape measure positioning component and the steel tape measure positioning component to be tested have the same structure and both comprise three columns (12). The three columns (12) are evenly fixed on the top of the main workbench (1) and enclose a receiving cavity for receiving the steel tape measure.

3. A tape measure calibration platform device according to claim 1, characterized in that: The movable clamp assembly (5) comprises a U-shaped seat (51) and two second extrusion screws (52), wherein the two second extrusion screws (52) are threadedly connected to the U-shaped seat (51), and the end of each second extrusion screw (52) extends into the U-shaped seat (51), and a hook (53) is provided at the bottom of the U-shaped seat (51), and the weight (3) is suspended on the hook (53).

4. A tape measure calibration platform device according to claim 3, characterized in that: The ends of the first extrusion screw (8) and the second extrusion screw (52) are both provided with spherical rubber heads (13), and the inner wall bottoms of the guide groove (11) and the U-shaped seat (51) are both provided with rubber pads (14).

5. A tape measure calibration platform device according to claim 3, characterized in that: The end of the adjusting screw (10) away from the sliding plate (7) and the top of the first extrusion screw (8) and the top of the second extrusion screw (52) are all movably connected with radially arranged handles (15).

6. A tape measure calibration platform device according to claim 1, characterized in that: The top surface of the working tail table (2) is also provided with a white silicone plate (16), and the end of the white silicone plate (16) away from the main working table (1) is provided with a rounded corner.

7. A tape measure calibration platform device according to claim 1, characterized in that: The main workbench (1) and the work tail platform (2), as well as the mounting plate (6) and the main workbench (1) are connected via a plurality of fastening bolts (17).

8. A tape measure calibration platform device according to any one of claims 1 to 7, characterized in that: A cylindrical pin (18) is also provided at the middle position of one end of the working tail table (2) away from the main working table (1), and a slide groove (19) is also provided at the middle position of one end of the working tail table (2) away from the main working table (1) and arranged along its axial direction, and the cylindrical pin (18) is slidably installed in the slide groove (19).

9. A tape measure calibration method, characterized in that: The method comprises the tape measure calibration platform device as described in claim 8, and includes zero value error detection and indication error detection, and the specific steps are as follows: S1: placing a standard steel tape measure (20) into a receiving cavity between three upright posts (12) of a standard steel tape measure positioning assembly corresponding to the positioning structure; S2: Pull the ruler (4) corresponding to the standard steel tape measure (20) to extend, so that the ruler (4) passes through the guide groove (11) corresponding to one of the sliding plates (7), with the front of the scale line facing upwards and the back of the scale line flatly attached to the top surface of the work tail table (2), until it extends to the end of the work tail table (2) away from the main work table (1), and hooks the bottom surface of the U-shaped seat (51) corresponding to the movable clamp assembly (5); S3: Hang the weight (3) on the hook (53) corresponding to the movable clamp assembly (5), and then use one of the second squeezing screws (52) corresponding to the movable clamp assembly (5) to squeeze and fix the end of the ruler (4) of the standard steel measuring tape (20), and at the same time use the first squeezing screw (8) above one of the sliding plates (7) to squeeze and fix the other end of the ruler (4) of the standard steel measuring tape (20); S4: placing the steel tape measure (21) to be tested into a receiving cavity between three upright posts (12) of the steel tape measure positioning assembly to be tested corresponding to the positioning structure; S5: Pull the rack (4) corresponding to the steel tape measure (21) to be tested to extend, so that the tape measure (4) passes through the guide groove (11) corresponding to the other sliding plate (7), with the front side of the scale line facing upwards and the back side of the scale line flatly attached to the top surface of the working tail table (2), until it extends to the end of the working tail table (2) away from the main working table (1), and hooks the bottom surface of the U-shaped seat (51) corresponding to the movable clamp assembly (5); S6: Using another second squeezing screw (52) corresponding to the movable clamp assembly (5) to squeeze and fix the end of the scale bar (4) of the steel measuring tape (21) to be tested, and simultaneously using another first squeezing screw (8) above the sliding plate (7) to squeeze and fix the other end of the scale bar (4) of the steel measuring tape (21) to be tested; S7: Read the error value between the steel tape measure (21) to be tested at the 500 mm scale line and the standard steel tape measure (20) at the 500 mm scale line, regard it as a zero value error, and record it; S8: Compare the steel tape measure (21) to be tested with the standard steel tape measure (20) at each meter scale line position, and calculate the indication error of each inspection point of the steel tape measure (21) to be tested, and record it. If the zero value error is within the standard range, and the indication error of each inspection point is within the standard range, the steel tape measure to be tested is qualified, otherwise, it is unqualified.

10. A tape measure calibration method according to claim 9, characterized in that: In the step S8, the indication error of each inspected point of the steel tape measure (21) to be inspected is calculated according to the following formula: △L=L-(LS20+δL) Where: △L—the indication error of the steel tape measure receiving point to be tested, L—nominal length of the inspection point of the steel tape to be tested, LS20 - actual length of standard steel tape at 20°C. δL—The deviation value of the test point of the steel tape to be tested read on the standard steel tape.

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