External diameter micrometer with three-point type percentage indication value
By using a three-point dial indicator for measuring the outer diameter of a micrometer, and through the design of a support base, measuring scale body, and positioning block, combined with the use of a dial indicator, the problem of insufficient accuracy in measuring the outer diameter of shaft-type components in existing technologies has been solved, achieving efficient and accurate testing results.
Patent Information
- Application Number
- CN202511180191.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-22
- Publication Date
- 2025-11-11
AI Technical Summary
Existing technologies cannot achieve high accuracy when measuring the outer diameter of shaft and disc components, especially in the fields of military and aerospace products and precision instruments, due to human error and the influence of equipment precision, making it difficult to achieve high-precision measurement.
The outside micrometer adopts a three-point dial indicator. Through the design of the support base, measuring scale body, protective bracket and positioning block, combined with the use of the dial indicator, the center line and the angle bisector are coincided. By using the center of the measuring part to roll up and down on the center line, the circumference is tangent to the angle line of the measuring instrument. By adjusting the size of the included angle of the tangent line, the measurement accuracy can be increased to 10 times or even 50 times that of the dial indicator.
This technology has increased the accuracy of external diameter measurement of parts, achieving 10 to 50 times the accuracy of dial indicators, thereby improving the accuracy and efficiency of inspection and reducing costs.
Smart Images
Figure CN120926844A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of inspection tool technology, and in particular to an outside micrometer with a three-point percentage display. Background Technology
[0002] An outside micrometer is an inspection tool used in mass production lines for machined shaft and disc parts. It is easy to operate, highly efficient and accurate, improving work efficiency while ensuring inspection accuracy. It also has wide applicability, low manufacturing cost, and good economic benefits.
[0003] Most existing methods for measuring the outer diameter of shaft discs use vernier calipers or micrometers. Vernier calipers typically have three accuracy levels: 0.1 mm, 0.05 mm, and 0.02 mm, while micrometers have an accuracy of 0.01 mm, which can be estimated to 0.001 mm. Both vernier calipers and micrometers require inspecting, reading, and recording one part at a time. This process demands a certain level of skill from the inspector and cannot be too fast. Furthermore, the operation of vernier calipers or micrometers is susceptible to human error and measurement errors due to the precision of the equipment. The maximum accuracy of a micrometer is 0.01 mm, making it difficult to meet higher precision requirements, especially in high-precision fields such as military and aerospace products and precision instruments. These fields demand extremely high precision in component processing, measurement accuracy, and consistency. To address these issues, a three-point percentage-indicating outer diameter micrometer is proposed. Summary of the Invention
[0004] This invention provides a three-point percentage-indicating outside micrometer, which solves the problems mentioned in the background art. The technical problem solved by this invention is achieved through the following technical solution: A three-point dial indicator for outside micrometers includes a support base, on which a measuring scale body and a protective bracket are sequentially arranged. The measuring scale body is semi-circular and forms a measuring area inside for the workpiece to be measured to be inserted. Two positioning blocks are distributed on the inner circumference of the measuring scale body, and the two positioning blocks are symmetrically arranged on the left and right sides along the center line of the measuring scale body. A dial indicator is provided above the measuring scale body, and the probe of the dial indicator extends through the measuring scale body into the measuring area. The dial indicator has a pointer and a dial for indicating the dimensional deviation of the measured workpiece. The support base is also equipped with a standard gauge, the size of which is the tolerance reference standard for the measured part, and the pointer of the dial indicator is set to zero with the "12 o'clock" position facing upwards. When the deviation is positive, the pointer deflects to the right, and when the deviation is negative, the pointer deflects to the left. The dial indicator is set with upper and lower half-zones according to the allowable tolerance of the part. When the pointer deflects to the left (or right) and moves out of the upper half-zone and into the lower half-zone, it is determined that the size deviation of the measured part is too large. The measurement method of the micrometer is as follows: the center line of the dial indicator measuring head and the bisector of the angle between the measuring scale body and the measuring part are coincident. The center of the measuring part rolls up and down on the center line, and the circumference is tangent to the bisector of the measuring tool to obtain the final measurement result. The two positioning blocks are respectively tangent to the outer periphery of the measuring component or standard gauge, extending outward from the dial indicator as the center. The two positioning blocks and the center of the measuring component or standard gauge respectively form a radius r / R. The actual deviation value of the measuring component is obtained by calculating the difference between the distance between the measuring component or standard gauge and the dial indicator and the radius. By adjusting the size of the included angle of the tangent lines, the detection accuracy of the outer circle dimension of the detected part can be expanded to 10 times, 20 times, 50 times or even higher accuracy range of the dial indicator.
[0005] Preferably, the bracket base protrudes upward between the measuring scale and the protective bracket to form a mounting plate for mounting the protective bracket and the measuring scale.
[0006] Preferably, the dial of the dial indicator has upper and lower limit blue zones for judging the accuracy of the workpiece to be measured.
[0007] Preferably, the dial indicator's axis is mounted on the centerline of the measuring scale.
[0008] Preferably, the two positioning blocks are arranged symmetrically on the left and right sides along the center line of the measuring ruler.
[0009] Preferably, the support base is rectangular in shape, and all corners are rounded.
[0010] Preferably, the two positioning blocks are detachably connected and disposed on the inner periphery of the measuring ruler.
[0011] The advantages and positive effects of this invention are as follows: The support base, measuring scale, and protective bracket enable the workpiece to be measured to be inserted for dimensional measurement. The positioning block ensures the alignment of the axis and angle bisector. The measurement is achieved by utilizing the principle that the center of the workpiece rolls up and down along the axis, with the circumference tangent to the angle line of the measuring tool. Furthermore, it allows for faster operation by skilled workers, enabling rapid batch testing. Adjusting the angle between the measuring body and the standard gauge tangents expands the accuracy of the outer diameter measurement of the parts to 10, 20, 50, or even higher than that of a dial indicator, accurately screening qualified parts to meet testing needs and significantly improving testing accuracy and efficiency. Attached Figure Description
[0012] The present invention will be further described below with reference to the accompanying drawings and embodiments.
[0013] Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 yes Figure 1 Schematic diagram of the structure of the middle support base; Figure 3 yes Figure 1 Schematic diagram of the structure of the measuring scale; Figure 4 This is a schematic diagram illustrating the principle of the present invention.
[0014] The markings in the attached diagram are described below: 1. Bracket base; 11. Mounting plate; 2. Measuring ruler; 21. Measuring area; 22. Positioning block; 3. Protective bracket; 4. Measuring components; 5. Percentage chart; 51. Upper half; 52. Lower half. Detailed Implementation
[0015] The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, illustrating only the basic structure of the invention, and therefore only show the components relevant to the invention.
[0016] The embodiments of the present invention will be further described in detail below with reference to the accompanying drawings: Reference Figure 1 and Figure 2 as well as Figure 3As shown, an outside micrometer is an inspection tool used in mass production lines for machined shaft and disc parts. It is easy to operate, highly efficient, and precise, improving work efficiency while ensuring inspection accuracy. It also has wide applicability, low manufacturing cost, and good economic benefits. Currently, most external diameter measurements for shafts and discs use vernier calipers or micrometers. Vernier calipers typically have three accuracy levels: 0.1 mm, 0.05 mm, and 0.02 mm, while micrometers have an accuracy of 0.01 mm, which can be estimated to 0.001 mm. Whether using vernier calipers or micrometers, the inspection, reading, and recording are done part by part. This entire process requires a certain level of skill from the inspector, and the speed cannot be too fast. Furthermore, the operation of vernier calipers or micrometers is susceptible to human error and environmental factors. The influence of various factors can cause certain motion errors, and the measurement error is also caused by the influence of equipment accuracy. In order to solve the above problems, a three-point dial indicator 5 is proposed as an outside micrometer, including a support base 1. The support base 1 is provided with a measuring scale body 2 and a protective bracket 3 in sequence. The measuring scale body 2 is arranged in a semi-circular shape, and a measuring area 21 for the workpiece to be measured to be inserted is formed inside. Two positioning blocks 22 are distributed on the inner circumference of the measuring scale body 2. The two positioning blocks 22 are symmetrically arranged on the left and right sides along the center line of the measuring scale body 2. A dial indicator 5 is provided above the measuring scale body 2. The probe of the dial indicator 5 extends through the measuring scale body 2 into the measuring area 21. The dial indicator 5 is provided with a pointer and a scale dial for indicating the dimensional deviation of the measured workpiece 4. The support base 1 is also equipped with a standard gauge, the size of which is the tolerance reference standard for the measuring part 4, and the pointer of the dial indicator 5 is set to zero with the "12 o'clock" position facing upwards; when the deviation is positive, the pointer deflects to the right, and when the deviation is negative, the pointer deflects to the left; the dial indicator 5 is set with an upper half zone 51 and a lower half zone 52 according to the allowable tolerance of the part; when the pointer deflects to the left (or right) and moves out of the upper half zone 51 and into the lower half zone 52, it is determined that the size deviation of the measuring part 4 is too large. The dial has a percentage scale value, and data can be collected and necessary judgments can be made as needed; The micrometer measurement method is as follows: by aligning the axis and the angle bisector, the center of the measuring part 4 rolls up and down on the axis, and the circumference line is tangent to the angle line of the measuring tool to obtain the final measurement result. The two positioning blocks 22 are respectively tangent to the outer periphery of the measuring piece 4 or standard gauge, extending outward from the dial indicator 5 as the center. The two positioning blocks 22 and the center of the measuring piece 4 or standard gauge respectively form a radius r / R. The actual deviation value of the measuring piece 4 is obtained by calculating the difference between the distance between the measuring piece 4 or standard gauge and the dial indicator 5 and the radius. The arrangement of the support base 1, the measuring scale body 2, and the protective bracket 3 achieves the purpose of inserting the workpiece to be measured for dimensional measurement. Furthermore, the positioning blocks 22 satisfy the requirements of the axis and angle. The measuring component 4 is measured by aligning the center line and using the principle that the circumference of the measuring component 4 rolls up and down on the axis, with the circumference line being tangent to the angle line of the measuring tool. This allows for faster operation by skilled workers, enabling rapid batch testing. Furthermore, by adjusting the angle between the tangent lines of the measuring ruler 2 and the standard gauge, the accuracy of the outer diameter measurement of the parts can be expanded to 10, 20, 50, or even higher than that of the dial indicator 5. This allows for precise screening of qualified parts, meeting testing requirements and greatly improving testing accuracy and efficiency.
[0017] It should be noted that this invention is both a measuring instrument and a standard measuring fixture. That is, it is a standard gauge calibration. The dial is set with upper and lower half zones of deviation 52. As long as the percentage pointer is in the upper half, it can be judged as qualified. Therefore, it greatly improves work efficiency and accuracy and effectively reduces costs.
[0018] Furthermore, in order to better distinguish between the upper and lower halves 52, in this embodiment, the upper and lower halves 52 can be visually distinguished by different colors, for example, the upper half 51 is a green area and the lower half 52 is a blue area.
[0019] It should also be noted that, in order to better install the measuring ruler 2 and the protective bracket 3, in this embodiment, the bracket base 1 is located between the measuring ruler 2 and the protective bracket 3 and protrudes upward to form a mounting plate 11 for installing the protective bracket 3 and the measuring ruler 2; the mounting plate 11 can better install and fix the measuring ruler 2 and the protective bracket 3, and avoid errors such as offset during the measurement process.
[0020] It is worth mentioning that by adjusting the angle between the measuring scale 2 and the standard gauge tangent, the accuracy of the outer circle dimension of the tested parts can be expanded to 10 times, 20 times, 50 times or even higher than that of the dial indicator 5, accurately screening qualified parts to meet the testing requirements. In this process, the measurement accuracy of the micrometer in this invention can reach 0.005 mm, 0.002 mm, 0.001 mm, or even higher.
[0021] Additionally, the specific principle behind the above measurement is as follows: (Refer to...) Figure 4As shown, point O is the vertex of angle ∠MON, OC is the angle bisector of angle ∠MON, and OM and ON are the sides of angle ∠MON. Where D is the center of the standard part, A is the point of tangency between the standard part and the corner line, OD is the distance from the center of the standard part to the vertex of angle ∠MON, AD=R, and R is the radius of the standard part. Where C is the center of the measuring part, M is the point of tangency between the standard part and the corner line, OC is the distance from the center of the measuring part to the vertex of angle ∠MON, CM=r, and r is the radius of the measuring part; a = ∠MON / 2; calculate: OD = R / sina; OC = r / sina; OC-OD = r / sina - R / sina; Let: S = OC - OD = DC, K = 1 / sina, where K is the measurement accuracy. Then: S=K(rR), rR = S / K, where rR is the actual deviation value of the measured part. Calculated: When K=10, a=5.73917°; When K=20, a=2.86598°; When K=50, a=1.147834°; By following this method, the required measurement accuracy and measurement range can be achieved; For example: R=175, K=10, the dial gauge measured DC=0.25mm; Therefore: r = R + (1 / K) * DC = 175 + (1 / 10) * 0.25 = 175 + 0.025 = 175.025; For example: R=175, K=100, the dial gauge measured DC=1.38mm; Then: r = R + (1 / K) * DC = 175 + (1 / 100) * 1.38 = 175 + 0.0138 = 175.0138.
[0022] By coinciding with the centerline and the angle bisector, the center of the measuring part rolls up and down along the centerline, and the circumference aligns with the angle line of the measuring instrument. Based on the principle of cutting, the components of this invention have a simple structure and low cost in practical applications. They are used for batch processing and inspection of parts, and the practical results are very good, truly realizing the benefits of a small tool with great function.
[0023] Correspondingly, the dial of the dial indicator is provided with upper and lower limit blue areas to determine the accuracy of the workpiece to be measured.
[0024] Additionally, the dial indicator 5 has its axis mounted on the centerline of the measuring scale 2.
[0025] Furthermore, the two positioning blocks 22 are symmetrically arranged on the left and right sides along the center line of the measuring ruler body 2.
[0026] Furthermore, the support base 1 is rectangular in shape, and all corners are rounded.
[0027] It should be noted that the two positioning blocks 22 are detachably connected to the inner circumference of the measuring ruler body 2.
[0028] It should be emphasized that the embodiments described in this invention are illustrative rather than limiting. Therefore, this invention is not limited to the embodiments described in the specific implementation. Any other implementation methods derived by those skilled in the art based on the technical solutions of this invention also fall within the scope of protection of this invention.
Claims
1. A three-point percentage-indicating outside micrometer, characterized in that: Includes a support base (1), on which a measuring scale (2) and a protective bracket (3) are arranged in sequence. The measuring scale (2) is arranged in a semi-circular shape and forms a measuring area (21) for the workpiece to be measured to be inserted. Two positioning blocks (22) are distributed on the inner circumference of the measuring scale (2). A dial indicator (5) is provided above the measuring scale (2). The probe of the dial indicator (5) extends through the measuring scale (2) into the measuring area (21). The dial indicator (5) is provided with a pointer for indicating the dimensional deviation of the measuring part (4). The micrometer's measurement principle is as follows: by utilizing the coincidence of the axis and the bisector of the angle, the center of the measuring part (4) rolls up and down on the axis, the outer circumference of the measuring part is tangent to the angle line of the measuring tool, and the difference between the dial indicator and the top of the measuring part is used to obtain the final measurement result of the diameter deviation of the measuring part; the required measurement deviation accuracy is achieved by adjusting the size of the angle α between the outer circumference of the measuring part and the angle line of the measuring tool. The two positioning blocks (22) extend outward from the outer periphery of the measuring part (4) or the standard gauge with the dial indicator (5) as the center and are tangent to each other. The two positioning blocks (22) and the center of the measuring part (4) or the standard gauge respectively form a radius r / R. The actual deviation value of the measuring part (4) is obtained by calculating the difference between the distance between the measuring part (4) or the standard gauge and the dial indicator (5) and the radius. With the 0-position contact point of the dial indicator as the vertex, the angle between the tangent lines on both sides of the standard gauge led out from the 0-position vertex is adjusted to achieve the effect of expanding the detection accuracy of the outer circle dimension of the detected parts to 10 times, 20 times, 50 times or even higher accuracy range of the dial indicator.
2. The three-point percentage-indicating outside micrometer according to claim 1, characterized in that: The bracket base (1) is located between the measuring scale body (2) and the protective bracket (3) and protrudes upward to form a mounting plate (11) for installing the protective bracket (3) and the measuring scale body (2).
3. The three-point percentage display outside micrometer according to claim 1, characterized in that: The dial of the instrument has upper and lower limit blue zones to determine the accuracy of the workpiece being tested.
4. The three-point percentage-indicating outside micrometer according to claim 1, characterized in that: The dial indicator (5) is mounted on the center line of the measuring scale (2).
5. The three-point percentage-indicating outside micrometer according to claim 1, characterized in that: The two positioning blocks (22) are symmetrically arranged on the left and right sides along the center line of the measuring ruler (2).
6. The three-point percentage-indicating outside micrometer according to claim 1, characterized in that: The support base (1) is rectangular in shape, and all corners are rounded.
7. The three-point percentage-indicating outside micrometer according to claim 1, characterized in that: The two positioning blocks (22) are detachably connected on the inner circumference of the measuring ruler body (2).