CN118705977A - A roundness measuring device and a roundness measuring method - Google Patents

Abstract

The invention discloses a roundness measuring device and a roundness measuring method, which relate to the technical field of measuring equipment, wherein an auxiliary measuring piece is provided with a first fulcrum and a measuring meter, and the first fulcrum and the measuring meter are both movably arranged on the auxiliary measuring piece; the measuring meter and the first supporting point are distributed along the circumferential direction of the inner ring or the outer ring of the workpiece to be measured; the measuring part of the measuring meter and the first supporting point are both used for contacting with the inner ring or the outer ring of the workpiece to be measured; the measuring meter and the first supporting point can synchronously rotate by taking the center of the equilateral triangle as a rotating shaft and the distance between the measuring meter and the center of the equilateral triangle as a radius; the movement direction of the measuring meter and the first supporting point is parallel to the radial direction of the equilateral triangle circumcircle; the roundness measuring device can measure the roundness of workpieces with various sizes, improves the overall efficiency of roundness measurement of the workpieces with various sizes, omits the step of carrying the workpieces, and improves the overall roundness measuring efficiency of the workpieces with various sizes.

Description

A roundness measuring device and a roundness measuring method

Technical Field

The present invention relates to the technical field of roundness measurement, and in particular to a roundness measuring device and a measuring method.

Background Art

In the prior art, when detecting the roundness of a large workpiece, the workpiece needs to be transferred to a three-dimensional coordinate measuring machine, and the roundness of a small workpiece needs to be measured using a roundness meter. This requires frequent switching of measuring tools for measuring small and large workpieces, and the overall measurement efficiency of the roundness of various types of workpieces is slow. In addition, large workpieces are large in size and heavy in weight, making them inconvenient to transport, further reducing the measurement efficiency of the workpiece roundness.

Therefore, how to improve the overall measurement efficiency of the roundness of workpieces of various types and sizes has become a technical problem that technical personnel in this field urgently need to solve.

Summary of the invention

The object of the present invention is to provide a roundness measuring device and a measuring method to improve the overall measuring efficiency of the roundness of workpieces of various types and sizes.

To achieve the above object, the present invention provides the following solutions:

The present invention provides a roundness measuring device, comprising an auxiliary measuring piece, on which two first fulcrums and a measuring table are arranged, and both the first fulcrums and the measuring table can be movably arranged on the auxiliary measuring piece;

The measuring table and the first supporting point are evenly distributed along the circumference of the inner ring or the outer ring of the workpiece to be measured;

The measuring part of the measuring table and the two first supporting points are used to contact the inner ring or the outer ring of the workpiece to be measured;

Between the measuring part of the measuring table and the two first supporting points, the connecting line between the two first supporting points can form an equilateral triangle, and the measuring table and the first supporting points can rotate synchronously with the center of the equilateral triangle as the rotation axis and the distance between the measuring table and the center of the equilateral triangle as the radius;

The moving directions of the measuring table and the first fulcrum are parallel to the radial direction of the circumscribed circle of the equilateral triangle.

Preferably, the auxiliary measuring member comprises three measuring rods;

The first ends of the three measuring rods are respectively provided with two of the first fulcrums and the measuring scale, and the second ends of the three measuring rods are integrated at one point. The measuring scale and the first fulcrum can move along the axial direction of the corresponding measuring rod.

Preferably, the second ends of the three measuring rods are respectively connected to the three interfaces of the three-way connector;

Alternatively, the second ends of the three measuring rods are connected to the same point.

Preferably, each of the measuring rods is provided with a first fastener for fixing the first fulcrum or the position of the measuring table.

Preferably, the roundness measuring device further comprises a limiter, and the limiter is used to prevent the first fulcrum and the measuring table from jumping along the axial direction of the workpiece to be measured.

Preferably, the limiting member includes three second fulcrums, the three second fulcrums are respectively arranged on the three measuring rods, the second fulcrums are used to contact the end surface of the workpiece to be measured, and the second fulcrums are arranged to avoid the first fulcrum.

Preferably, each of the three measuring rods is provided with a second fulcrum, the second fulcrum can move along the axial direction of the corresponding measuring rod, and a second fastener for fixing the second fulcrum is provided on the measuring rod.

Preferably, the auxiliary measuring member comprises a first turntable, the two first fulcrums and the measuring table are distributed along the circumference of the first turntable, and the first fulcrums and the measuring table can move along the radial direction of the first turntable.

Preferably, the roundness measuring device further comprises a second turntable, a first end of the second turntable is provided with a rotating handle, and the first fulcrum and the measuring table are both connected to the second turntable.

In addition, the present invention also provides a roundness measuring method using the roundness measuring device, comprising the following contents:

If the workpiece to be measured has an odd number of edges, the roundness measurement method comprises the following steps: step S1, according to the size of the workpiece to be measured, adjusting the positions of the first fulcrum and the measuring table along the radial direction of the circumscribed circle of the equilateral triangle, so that the first fulcrum and the measuring part of the measuring table are in contact with the inner circle or the outer circle of the workpiece to be measured;

Step S2, rotating the first fulcrum and the measuring table so that the measuring table measures one circle of the inner circle or outer circle of the workpiece to be measured;

Step S3, measuring the difference between the maximum indication and the minimum indication of the inner circle or the outer circle of the workpiece to be measured according to the measuring table, and obtaining the roundness of the workpiece to be measured;

If the workpiece to be measured has an even number of edges, the roundness measurement method comprises the following steps: step A, the first fulcrum and the measuring table are arranged at intervals along the circumference of the inner ring or the outer ring of the workpiece to be measured, the angle between the two first fulcrums is 90°, the angle between the measuring table and one of the first fulcrums is 90°, and the angle between the measuring table and another of the first fulcrums is 180°;

Step B, rotating the first fulcrum and the measuring table so that the measuring table measures one circle of the inner circle or outer circle of the workpiece to be measured;

Step C, measuring the difference between the maximum indication and the minimum indication of the inner circle or the outer circle of the workpiece to be measured according to the measuring table, and obtaining the roundness of the workpiece to be measured.

Compared with the prior art, the present invention has achieved the following technical effects:

In the present invention, the first fulcrum and the measuring table are evenly distributed along the circumference of the inner ring or outer ring of the workpiece to be measured, the first fulcrum and the connecting lines between the measuring parts of the measuring table can form an equilateral triangle, and the first fulcrum and the measuring table can rotate with the center of the equilateral triangle as the rotation axis and the distance between the center of the equilateral triangle and the measuring table or the first fulcrum as the radius, so that the roundness measuring device in the present invention can realize the measurement of the roundness of the workpiece to be measured.

Furthermore, the moving directions of the measuring table and the first fulcrum are parallel to the radial direction of the circumscribed circle of the equilateral triangle, which means that by adjusting the positions of the measuring table and the first fulcrum, the first fulcrum and the measuring table can be brought into contact with the inner ring or outer ring of workpieces of different sizes and types, and measurements can be performed, which eliminates the need to replace different measuring tools for roundness measurement of small and large workpieces, so that operators can measure the roundness of workpieces of various sizes and types using only the roundness measuring device of the present invention, thereby improving the overall roundness measurement efficiency of workpieces of different types and sizes. Furthermore, operators can measure the roundness of different workpieces by moving the roundness measuring device to different workpieces, thereby eliminating the need to transport workpieces, especially large-sized workpieces, and further improving the overall roundness measurement efficiency of workpieces of different types and sizes.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

FIG1 is a schematic diagram of the structure of a roundness measuring device for measuring the roundness of the outer diameter of a workpiece;

Fig. 2 is a cross-sectional view of Fig. 1;

FIG3 is a schematic diagram of the structure of a roundness measuring device when measuring the roundness of the inner diameter of a workpiece;

FIG4 is a cross-sectional view of FIG3 ;

FIG5 is a schematic structural diagram of a first fulcrum;

Among them, 1. the first fulcrum; 2. the measuring table; 3. the measuring rod; 4. the three-way connector; 5. the first fastener; 6. the second fulcrum; 7. the second fastener; 8. the workpiece to be measured.

DETAILED DESCRIPTION

The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

As shown in Figures 1 to 5, the present invention discloses a roundness measuring device, including an auxiliary measuring piece, on which are provided two first fulcrums 1 and a measuring table 2, both of which are movably arranged on the auxiliary measuring piece; the measuring table 2 and the first fulcrum 1 are distributed along the circumference of the inner ring or outer ring of the workpiece 8 to be measured; the measuring part of the measuring table 2 and the two first fulcrums 1 are both used to contact the inner ring or outer ring of the workpiece 8 to be measured; between the measuring part of the measuring table 2 and the two first fulcrums 1, the connecting line between the two first fulcrums 1 can form an equilateral triangle, the measuring table 2 and the first fulcrum 1 can synchronously rotate with the center of the equilateral triangle as the rotation axis and the distance between the measuring table 2 and the center of the equilateral triangle as the radius; the moving direction of the measuring table 2 and the first fulcrum 1 is parallel to the radial direction of the circumscribed circle of the equilateral triangle.

In the present invention, the first fulcrum 1 and the measuring table 2 are evenly distributed along the circumference of the inner ring or outer ring of the workpiece 8 to be measured, and the connecting lines between the first fulcrum 1 and the measuring parts of the measuring table 2 can form an equilateral triangle, and the first fulcrum 1 and the measuring table 2 can rotate with the center of the equilateral triangle as the rotation axis and the distance between the center of the equilateral triangle and the measuring table 2 or the first fulcrum 1 as the radius, which enables the roundness measuring device in the present invention to measure the roundness of the workpiece to be measured.

Furthermore, the moving directions of the measuring table 2 and the first fulcrum 1 are parallel to the radial direction of the circumscribed circle of the equilateral triangle, which means that by adjusting the positions of the measuring table 2 and the first fulcrum 1, the first fulcrum 1 and the measuring table 2 can be brought into contact with the inner ring or outer ring of workpieces of different sizes and types, and measurements can be performed, which eliminates the need to replace different measuring tools for roundness measurement of small workpieces and large workpieces, so that the operator can measure the roundness of workpieces of various sizes and types only by using the roundness measuring device of the present invention, thereby improving the overall roundness measurement efficiency of workpieces of different types and sizes. Furthermore, the operator can measure the roundness of different workpieces by moving the roundness measuring device to different workpieces, thereby eliminating the need to transport workpieces, especially large-sized workpieces, and further improving the overall roundness measurement efficiency of workpieces of different types and sizes.

It should be noted that in the present invention, the head of the measuring table 2, the first fulcrum 1 and the inner ring or outer ring of the workpiece 8 to be measured are all in point contact. Compared with line contact or surface contact, the contact area between the head of the measuring table 2 and the inner ring or outer ring of the workpiece 8 to be measured is smaller, which reduces the measurement error caused by the uneven contact surface of the workpiece 8 to be measured and the head of the measuring table 2 or the deformation of the contact point; and reduces the measurement interference caused by friction and sliding, so that the head of the measuring table 2 can perform measurements stably, thereby improving the accuracy of the roundness measurement of the workpiece 8 to be measured by the head of the measuring table 2.

In the present invention, the measuring gauge 2 can be a micrometer. As shown in Figures 1 to 5, the direction in which the measuring gauge 2 and the first fulcrum 1 move is the midline direction of the equilateral triangle. The measuring part of the measuring gauge refers to the gauge head of the measuring gauge.

Furthermore, the header of the measuring table 2 and the first fulcrum 1 in the present invention are located at the same height of the horizontal plane, which provides a unified reference plane, thereby improving the accuracy of the roundness measurement of the workpiece 8 to be measured: if the header of the measuring table 2 and the first fulcrum 1 are not at the same height of the horizontal plane, a deviation in the vertical direction will be introduced during the measurement process of the measuring table 2, thereby reducing the accuracy of the measurement of the measuring table 2. Furthermore, when the first fulcrum 1 and the header of the measuring table 2 are at the same height of the horizontal plane, the calibration of the roundness measuring device in the present invention is more convenient, and there is no need to consider whether there is a height difference between the first fulcrum 1 and the measuring table 2, thereby simplifying the operation steps.

At the same time, the head of the measuring table 2, the first fulcrum 1 and the inner ring or outer ring of the workpiece 8 to be measured are arranged vertically in the present invention; this ensures that the measuring direction of the measuring table 2 is consistent with the normal direction of the surface of the workpiece 8 to be measured, and avoids the sliding or displacement of the head of the measuring table 2 and the first fulcrum 1 due to lateral force during the measurement process, so that the head of the measuring table 2 and the first fulcrum 1 can consistently contact the same position of the inner ring or outer ring of the workpiece 8 to be measured, reducing the error caused by the change of the contact point during the measurement process, and ensuring the consistency and repeatability of the measurement results.

In the present invention, the fulcrum and the measuring table 2 can be arranged on a variety of structures, as long as it can ensure that the function of "the measuring table 2 and the two first fulcrums 1, the connecting line between the two first fulcrums 1 can form an equilateral triangle, the moving direction of the measuring table 2 and the first fulcrum 1 is parallel to the radial direction of the circumscribed circle of the equilateral triangle, the center of the equilateral triangle is used as the rotation axis, and the measuring table 2 rotates synchronously with the distance between the center of the equilateral triangle as the radius" can be achieved.

As shown in Figures 1 to 5, the auxiliary measuring parts also include three measuring rods 3. The first ends of the three measuring rods 3 are respectively provided with two first fulcrums 1 and a measuring table 2. The second ends of the three measuring rods 3 are integrated at one point (the point is called an integration point). The measuring table 2 and the first fulcrum 1 can move along the axial direction of the corresponding measuring rod 3. The three measuring rods 3 are evenly distributed along the circumference with the integration point of the second ends of the three measuring rods 3 as the center of the circle, that is, the angle between adjacent measuring rods 3 is 120°; the distance between the two first fulcrums 1 and the integration point is equal, so as to ensure that the connection line between the measuring table 2 and the two first fulcrums 1 and between the two first fulcrums 1 can form an equilateral triangle. The length of the measuring rod 3 is long enough so that the measuring rod 3 can be applied to the roundness measurement of workpieces of various types and sizes. As shown in Figures 1 and 3, the measuring rod 3 in the present invention can be placed on the end face of the workpiece 8 to be measured to measure the roundness of the workpiece 8 to be measured, and the structure of the roundness measuring device in the present invention is relatively simple. Therefore, when the operator measures the roundness of workpieces 8 to be measured in various sizes and types, there is no need to move the workpieces, but only to move the roundness measuring device, thereby eliminating the need for the transport step in the process of measuring the roundness of various workpieces, saving manpower, and improving the overall efficiency of measuring the roundness of workpieces of various sizes.

Moreover, there are various forms of integrating the second ends of the three measuring rods 3 at one point. For example, the second ends of the three measuring rods 3 can be welded at one point. In this case, the integration point is the point where the second ends of the three measuring rods 3 are welded together; or, the three measuring rods 3 are an integrally formed structure. In this way, the second ends of the three measuring rods 3 are naturally connected together. In this case, the integration point is the center point of the integrally formed structure; or, as shown in Figures 1 to 4, the second ends of the three measuring rods 3 are respectively connected to the three interfaces of the three-way connector 4. In this case, the integration point is the center point of the three-way connector 4.

In the present invention, each measuring rod 3 is provided with a first fastener 5 for fixing the position of the first fulcrum 1 or the measuring table 2. As shown in Figures 1 to 4, when it is necessary to adjust the position of the first fulcrum 1 or the measuring table 2 on the measuring rod 3, the first fastener 5 is loosened, and the first fulcrum 1 or the measuring table 2 is moved on the measuring rod 3. After the first fulcrum 1 or the measuring table 2 is moved to the desired position, the first fulcrum 1 or the measuring table 2 is fixed to the measuring rod 3 by the first fastener 5, thereby avoiding displacement of the first fulcrum 1 or the measuring table 2 during the measurement process, and ensuring the accuracy of the workpiece roundness measurement. In addition, the first fastener 5 is provided so that the position of the first fulcrum 1 and the measuring table 2 can extend downward relative to the measuring rod 3, so that the first fulcrum 1 and the measuring table 2 can contact the outer ring or inner ring of the workpiece 8 to be measured.

The roundness measuring device of the present invention further includes a stopper, which is used to prevent the first fulcrum 1 and the measuring table 2 from jumping along the axial direction of the workpiece 8 to be measured. The stopper can be a stopper block, a stopper protrusion or a stopper plate and other structures arranged on the three support rods. The stopper prevents the first fulcrum 1 and the measuring table 2 from deviating downward during the process of measuring the roundness of the workpiece, resulting in a vertical error introduced during the workpiece roundness measurement process, and reducing the accuracy of the workpiece roundness measurement.

As shown in Figures 1 to 4, the limiter includes three second fulcrums 6, which are respectively arranged on three measuring rods 3. The second fulcrum 6 is used to contact the end face of the workpiece 8 to be measured, and can be specifically arranged vertically, and the first fulcrum 1 and the second fulcrum 6 are arranged to avoid each other. The second fulcrum 6 is supported on the end face of the workpiece 8 to be measured, so as to prevent the first fulcrum 1 and the measuring table 2 from being displaced during the measurement process, thereby ensuring the accuracy of the workpiece roundness measurement. Since the second fulcrum 6 is perpendicular to the end face of the workpiece 8 to be measured, the second fulcrum 6 can provide a stable supporting surface, ensuring that the axial position of the first fulcrum 1 and the measuring table 2 on the workpiece 8 to be measured will not be disturbed, thereby ensuring the accuracy of the measurement; the second fulcrum 6 arranged vertically can help maintain the stability of the entire measuring device, and its supporting effect in the vertical direction can reduce the measurement error caused by the movement or vibration of the first fulcrum 1 and the measuring table 2.

The avoidance setting of the first fulcrum 1 and the second fulcrum 6 means that the first fulcrum 1 and the second fulcrum 6 will not affect their respective functions and movements.

As shown in Fig. 1 to Fig. 4, in the present invention, a second fulcrum 6 is respectively provided on the three measuring rods 3, and the second fulcrum 6 can move along the axial direction of the corresponding measuring rod 3, and a second fastener 7 for fixing the second fulcrum 6 is provided on the measuring rod 3. Loosening the second fastener 7 can adjust the position of the second fulcrum 6 on the measuring rod 3, and tightening the second fastener 7 can fix the position of the second fulcrum 6 on the measuring rod 3. The first fulcrum 1 and the second fulcrum 6 can be structures that can play a supporting role, such as a supporting protrusion, a supporting ball or a supporting plate, but it is necessary to ensure that the first fulcrum 1 and the workpiece 8 to be measured are in point contact, and the first fulcrum 1 and the workpiece 8 to be measured are arranged vertically.

Furthermore, in the present invention, the first fulcrum 1 and the measuring table 2 can not only be set on the measuring rod 3, but also can be set on other structures that can meet the function of "between the measuring table 2 and the two first fulcrums 1, the line between the two first fulcrums 1 can form an equilateral triangle, the moving direction of the measuring table 2 and the first fulcrum 1 is parallel to the radial direction of the circumscribed circle of the equilateral triangle, with the center of the equilateral triangle as the rotation axis, and the distance between the measuring table 2 and the center of the equilateral triangle as the radius to rotate synchronously". For example, the auxiliary measuring part includes a first turntable, the two first fulcrums 1 and the measuring table 2 are evenly distributed along the circumference of the first turntable, and the first fulcrum 1 and the measuring table 2 can move along the radial direction of the first turntable. The diameter of the first turntable is large enough so that the first turntable can be used for roundness measurement of workpieces of various sizes. The first fulcrum 1 and the measuring table 2 can be moved radially along the first turntable by setting a corresponding slide rail in the radial direction of the first turntable, and the first fulcrum 1, the measuring table 2 and the sliding cooperation with the slide rail, and a plurality of limit holes can be set in the slide rail. When the first fulcrum 1 and the measuring table 2 need to move along the slide rail, the limit rod inserted in the limit hole is taken out, and after the first fulcrum 1 and the measuring table 2 are moved to the required positions, the limit rod is inserted into the limit hole at the corresponding position, thereby fixing the positions of the first fulcrum 1 and the measuring table 2, avoiding the problem of inaccurate roundness measurement of the workpiece caused by the offset of the first fulcrum 1 and the measuring table 2 during the process of measuring the roundness of the workpiece.

In the present invention, the rotation of the first fulcrum 1 and the measuring table 2 around the inner or outer ring of the workpiece 8 to be measured can be achieved by the operator manually turning the measuring rod 3. It can also be achieved with the assistance of other tools. For example, the roundness measuring device also includes a second turntable, and a rotating handle is provided at the first end of the second turntable. The two first fulcrums 1 and the measuring table 2 are evenly distributed along the circumference of the second turntable, and the first fulcrum 1 and the measuring table 2 are both connected to the second turntable. After the positions of the first fulcrum 1 and the measuring table 2 are adjusted and the workpiece roundness measurement is ready to start, the operator can drive the first fulcrum 1 and the measuring table 2 to rotate along the inner or outer ring of the workpiece 8 to be measured by operating the rotating handle, thereby completing the measurement of the roundness of the workpiece. Among them, the first fulcrum 1 and the measuring table 2 are both connected to the second turntable, which does not necessarily mean that the first fulcrum 1 and the measuring table 2 are directly connected to the second turntable, and they can also be indirectly connected through other structures. For example, the two first fulcrums 1 and the measuring scale 2 can be directly set on the second turntable along the circumference of the second turntable. At this time, the second turntable is directly connected to the first fulcrum 1 and the measuring scale 2; the second end of the second turntable can also be connected to the first turntable or the three measuring rods 3. In this way, when the second turntable is rotated by turning the handle, the first fulcrum 1 and the measuring scale 2 can also be driven to rotate along the inner ring or outer ring of the workpiece 8 to be measured, thereby completing the roundness measurement of the workpiece 8 to be measured.

In addition, the present invention also provides a roundness measuring method using a roundness measuring device, comprising the following contents: if the workpiece to be measured has an odd number of edges, the roundness measuring method comprises the following steps: step S1, according to the size of the workpiece to be measured, adjusting the position of the first fulcrum and the measuring table along the radial direction of the circumscribed circle of the equilateral triangle, so that the first fulcrum and the measuring part of the measuring table are in contact with the inner ring or outer ring of the workpiece to be measured; step S2, rotating the first fulcrum and the measuring table, so that the measuring table measures one circle of the inner ring or outer ring of the workpiece to be measured; step S3, measuring the difference between the maximum indication and the minimum indication of one circle of the inner ring or outer ring of the workpiece to be measured according to the measuring table, and obtaining the roundness of the workpiece to be measured;

If the workpiece to be measured has an even number of edges, the roundness measurement method includes the following steps: step A, setting the first fulcrum and the measuring table at intervals along the circumference of the inner ring or outer ring of the workpiece to be measured, the angle between the two first fulcrums is 90°, the angle between the measuring table and one of the first fulcrums is 90°, and the angle between the measuring table and the other first fulcrum is 180°; step B, rotating the first fulcrum and the measuring table so that the measuring table measures one circle of the inner ring or outer ring of the workpiece to be measured; step C, measuring the difference between the maximum indication and the minimum indication of one circle of the inner ring or outer ring of the workpiece to be measured according to the measuring table, and obtaining the roundness of the workpiece to be measured.

Furthermore, after the roundness measuring device of the present invention completes the measurement of the inner diameter roundness of the workpiece 8 to be measured, the positions of the first fulcrum 1 and the second fulcrum 6 can be swapped so that the roundness measuring device can measure the outer diameter roundness of the workpiece.

It should be noted that, as shown in Figures 1 to 4, the workpiece 8 to be measured is a bearing, but the roundness measuring device in the present invention is not limited to the measurement of bearings. Other workpieces with inner cylindrical surfaces, outer cylindrical surfaces, etc. that need to be measured for roundness can also be measured by the roundness measuring device in the present invention.

The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims (10)

1. The roundness measuring device is characterized by comprising an auxiliary measuring piece, wherein two first supporting points and a measuring meter are arranged on the auxiliary measuring piece, and the first supporting points and the measuring meter are movably arranged on the auxiliary measuring piece;

The measuring meter and the first supporting point are distributed along the circumferential direction of the inner ring or the outer ring of the workpiece to be measured;

the measuring part of the measuring meter and the two first supporting points are both used for contacting with the inner ring or the outer ring of the workpiece to be measured;

the measuring part of the measuring meter and the two first supporting points can form an equilateral triangle by connecting the two first supporting points, the center of the equilateral triangle can be used as a rotating shaft, and the distance between the measuring meter and the center of the equilateral triangle can be used as a radius for synchronous rotation;

the moving direction of the measuring meter and the first supporting point is parallel to the radial direction of the circumcircle of the equilateral triangle.

2. The roundness measuring apparatus of claim 1, wherein the auxiliary measurement member includes three measurement bars;

The first ends of the three measuring rods are respectively provided with two first supporting points and measuring meters, the second ends of the three measuring rods are integrated at one point, and the measuring meters and the first supporting points can move along the axial direction of the corresponding measuring rods.

3. The roundness measuring apparatus according to claim 2, wherein second ends of the three measuring bars are respectively connected to three interfaces of a three-way connecting piece;

or the second ends of the three measuring rods are connected to the same point.

4. The roundness measuring apparatus of claim 2, wherein each of the measuring bars is provided with a first fastener for fixing the position of the first fulcrum or the gauge.

5. The roundness measuring apparatus of claim 2, further comprising a stopper for preventing the first fulcrum and the gauge from bouncing along an axial direction of the workpiece to be measured.

6. The roundness measuring apparatus of claim 5, wherein the stopper includes three second fulcrums, the three second fulcrums are respectively provided on the three measuring bars, the second fulcrums are for contacting with an end surface of the workpiece to be measured, and the second fulcrums are provided so as to avoid the first fulcrums.

7. The roundness measuring apparatus of claim 6, wherein each of the three measuring bars is provided with one of the second fulcra, the second fulcra being movable in the axial direction of the corresponding measuring bar, and the measuring bar is provided with a second fastener for fixing the second fulcra.

8. The roundness measuring apparatus of claim 1, wherein the auxiliary measurement member includes a first turntable, two of the first fulcrums and the gauge are distributed along a circumferential direction of the first turntable, and the first fulcrums and the gauge are movable in a radial direction of the first turntable.

9. The roundness measuring apparatus of any of claims 1,2, 8, further comprising a second turntable, a first end of the second turntable being provided with a turning handle, the first fulcrum and the gauge both being connected to the second turntable.

10. A roundness measurement method using the roundness measurement apparatus of any one of claims 1 to 9, comprising:

if the workpiece to be measured has odd edges, the roundness measuring method comprises the following steps: step S1, according to the size of a workpiece to be detected, the positions of a first supporting point and a measuring meter are adjusted along the radial direction of an circumscribed circle of the equilateral triangle, so that the first supporting point and a measuring part of the measuring meter are in contact with an inner ring or an outer ring of the workpiece to be detected;

s2, rotating the first supporting point and the measuring meter to enable the measuring meter to measure one circle of the inner ring or the outer ring of the workpiece to be measured;

Step S3, measuring the difference value between the maximum indication value and the minimum indication value of the circumference of the inner ring or the outer ring of the workpiece to be measured according to the measuring meter to obtain the roundness of the workpiece to be measured;

If the workpiece to be measured has even edges, the roundness measuring method comprises the following steps: step A, arranging the first supporting points and the measuring meter at intervals along the circumferential direction of the inner ring or the outer ring of the workpiece to be measured, wherein an included angle between the two first supporting points is 90 degrees, an included angle between the measuring meter and one of the first supporting points is 90 degrees, and an included angle between the measuring meter and the other first supporting point is 180 degrees;

step B, rotating the first supporting point and the measuring meter to enable the measuring meter to measure one circle of the inner ring or the outer ring of the workpiece to be measured;

And C, measuring the difference value between the maximum indication value and the minimum indication value of the circumference of the inner ring or the outer ring of the workpiece to be measured according to the measuring meter to obtain the roundness of the workpiece to be measured.