Inner diameter measurement device and inner diameter measurement system

The inner diameter measuring device with openable arms and a chuck device addresses the need for frequent guide changes by enabling direct contact measurement, reducing labor and preventing surface damage, thus facilitating efficient and versatile inner diameter assessments.

JP2025109024APending Publication Date: 2025-07-24MURATA MASCH LTD
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Patent Information

Application Number
JP2024002671
Authority / Receiving Office
JP · JP
Patent Type
Applications
Current Assignee / Owner
Filing Date
2024-01-11
Publication Date
2025-07-24

AI Technical Summary

Technical Problem

Existing inner diameter measuring devices require the use of an inner diameter guide, which necessitates frequent changes when the size of the measurement hole changes, leading to time-consuming adjustments and potential damage to the inner diameter surface.

Method used

An inner diameter measuring device with openable and closable measurement arms, each comprising a first portion extending in a first direction and a second portion bent in a second direction, allowing direct contact with the inner diameter surface without the need for an inner diameter guide, and a chuck device with claw portions to center the workpiece.

Benefits of technology

Enables measurement of inner diameters without an inner diameter guide, reducing labor and preventing damage to the inner diameter surface, while allowing for continuous use across varying hole sizes and smaller measurements.

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Abstract

To provide an inner diameter measurement device and an inner diameter measurement system capable of measuring a measurement hole without using an inner diameter guide.SOLUTION: An inner diameter measurement device 10 causes a contact piece 40 to contact with an inner diameter surface of a measurement hole 100 of a work piece W to measure an inner diameter of the measurement hole 100. The inner diameter measurement device includes a pair of closable measurement arms 11. Each of the measurement arms 11 includes a first part 30 extending in a first direction, and a second part 35 bending and extending in a second direction intersecting the first direction from an end portion of the first part 30. The second part 35 includes a contact piece 40 at a tip thereof.SELECTED DRAWING: Figure 1
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Description

Technical Field

[0001] The present invention relates to an inner diameter measuring device and an inner diameter measuring system.

Background Art

[0002] An inner diameter measuring device is known that measures the inner diameter of a measurement hole by bringing a contact into contact with the inner diameter surface of the measurement hole of a workpiece (see, for example, Patent Document 1). This inner diameter measuring device includes an inner diameter guide that protects the inner diameter of the measurement hole, and a pair of linear measurement arms housed therein. A contact is attached to the tip of the measurement arm. When measuring the inner diameter of the measurement hole, first, the inner diameter guide is inserted into the measurement hole. Then, with the inner diameter guide inserted into the measurement hole, the pair of measurement arms are opened to bring the contact into contact with the inner diameter surface of the measurement hole.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the above inner diameter measuring device, when measuring the inner diameter of the measurement hole, it is necessary to insert the inner diameter guide into the measurement hole. Therefore, every time the size of the measurement hole changes, it may be necessary to change to an inner diameter guide that fits the measurement hole, which is time-consuming.

[0005] An object of the present invention is to provide an inner diameter measuring device and an inner diameter measuring system that can measure a measurement hole without using an inner diameter guide.

Means for Solving the Problems

[0006] The inner diameter measuring device according to an aspect of the present invention is an inner diameter measuring device that measures the inner diameter of a measurement hole of a workpiece by bringing a contact into contact with the inner diameter surface of the measurement hole, and has a pair of openable and closable measurement arms. Each of the measurement arms includes a first portion extending in a first direction and a second portion bent and extending in a second direction intersecting the first direction from an end of the first portion, and the contact is provided at a tip of the second portion.

[0007] The inner diameter measuring system according to an aspect of the present invention includes a chuck device having a plurality of claw portions arranged side by side around the axis of a first central axis, and an inner diameter measuring device that measures the inner diameter of a measurement hole of a workpiece held by the chuck device by bringing a contact into contact with the inner diameter surface of the measurement hole. The chuck device holds the workpiece in a state where the first central axis coincides with a second central axis that is the central axis of the measurement hole by moving the plurality of claw portions radially inward. The inner diameter measuring device has a pair of openable and closable measurement arms. Each of the measurement arms includes a first portion extending in a first direction and a second portion bent and extending in a second direction intersecting the first direction from an end of the first portion, and the contact is provided at a tip of the second portion.

Advantages of the Invention

[0008] The inner diameter measuring device and the inner diameter measuring system according to an aspect of the present invention have a pair of openable and closable measurement arms. Each measurement arm includes a first portion extending in a first direction and a second portion having a contact and bent and extending in a second direction intersecting the first direction from an end of the first portion. With such a configuration, the inner diameter of the measurement hole 100 can be measured without using an inner diameter guide, and the labor of replacing the inner diameter guide can be reduced. Further, when inserting the measurement arm into the measurement hole of the workpiece with the loader device, it is possible to prevent the inner diameter surface of the workpiece from being damaged by the inner diameter guide.

[0009] In the inner diameter measuring device according to the above aspect, the second direction may be a direction orthogonal to the first direction. Further, in the inner diameter measuring device according to the above aspect, a measuring head that rotatably supports the pair of measuring arms is provided, and in the first part, the first end of the first part is rotatably supported by the measuring head and protrudes and extends in the first direction from the measuring head. The second part may extend in the second direction from the second end of the first part. With such a configuration, the tip of the second part can be inserted into the measurement hole of the work from the lower surface of the work.

[0010] In the inner diameter measuring system according to the above aspect, the second direction is a direction orthogonal to the first direction and may be parallel to the axial direction of the first central axis. The chuck device has a main body portion that holds the plurality of claw portions so as to be movable in the radial direction. The first portion extends along the first direction at a position above the main body portion and lower than the plurality of claw portions. The second portion extends vertically upward from the end of the first portion. When the work is held by the chuck device, the tip of the second portion may be inserted into the measurement hole from below the work. With such a configuration, the tip of the measuring arm can be inserted vertically upward from the lower surface of the work to measure the hole diameter of the measurement hole.

Brief Description of Drawings

[0011]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Mode for Carrying Out the Invention

[0012] Hereinafter, the present invention will be described through embodiments. However, the following embodiments do not limit the invention according to the claims. Also, not all combinations of features described in the embodiments are essential for the solution means of the invention. In the drawings, the same or similar parts may be denoted by the same reference numerals, and redundant descriptions may be omitted. In addition, the shape and size of the elements in the drawings may be exaggerated for clearer explanation, and thus may be different in shape and dimensions from the actual product.

[0013] In FIG. 1, the directions in the figure may be described using the XYZ coordinate system. In the XYZ coordinate system, a plane parallel to the horizontal plane is defined as the XY plane. One direction in this XY plane is denoted as the X direction, and the direction orthogonal to the X direction is denoted as the Y direction. Further, the direction perpendicular to the XY plane is denoted as the Z direction.

[0014] FIG. 1 is a plan view of an inner diameter measurement system IDMS according to the present embodiment. FIG. 2 is a side cross-sectional view of the inner diameter measurement system IDMS according to the present embodiment. The inner diameter measurement system IDMS includes an inner diameter measurement device (bore gauge) 10 and a chuck device 20.

[0015] The inner diameter measurement device 10 measures the inner diameter of a hole formed in the workpiece W. In the example shown in FIGS. 1 and 2, the shape of the workpiece W is shown as cylindrical, but it may have a shape other than cylindrical. The inner diameter measurement device 10 is fixed to, for example, a machine tool. Hereinafter, the hole whose inner diameter is measured by the inner diameter measurement device 10 may be referred to as the "measurement hole 100".

[0016] The inner diameter measuring device 10 includes a pair of measuring arms 11 and a measuring head 12. When distinguishing each of the pair of measuring arms 11, one measuring arm 11 is designated as the "measuring arm 11a", and the other measuring arm 11 is designated as the "measuring arm 11b". Also, for the purpose of distinguishing multiple components of the same type from each other, an "a" may be appended to the end of the reference numeral of each component of the measuring arm 11a, and a "b" may be appended to the end of the reference numeral of each component of the measuring arm 11b.

[0017] The measuring arm 11 includes a first portion 30 extending in a first direction, a second portion 35 extending in a second direction different from the first direction, and a contact 40 provided on the second portion 35.

[0018] The first portion 30 extends in the first direction. In the example shown in FIGS. 1 and 2, the first direction is the X direction. The first end of the first portion 30 is pivotally supported by the measuring head 12. In the example shown in FIG. 1, the first end of the first portion 30 is pivotally supported so as to be rotatable about an axis parallel to the Z direction as a pivot axis.

[0019] The second portion 35 extends by bending in the second direction from the second end of the first portion 30. The second direction is a direction intersecting the first direction. In the example shown in FIGS. 1 and 2, the second direction is a direction orthogonal to the first direction. That is, the shape of the measuring arm 11 shown in FIGS. 1 and 2 is bent in an L shape. Note that the second direction shown in the drawing is the Z direction.

[0020] In FIGS. 1 and 2, when the first portion 30 is viewed such that the first direction is parallel to the X direction, the second portion 35 is bent in the +Z direction from the second end of the first portion 30. Note that the second portion 35 may be a member separate from the first portion 30 or may be a member integral with the first portion 30. Note that the shape of the measuring arm 11 does not necessarily have to be in an L shape. That is, the second direction is not limited to a direction orthogonal to the first direction and may be any direction intersecting the first direction.

[0021] The contact 40 is provided at the tip of the second portion 35. The tip means a portion including a certain range in the axial direction (the -Z direction shown in FIG. 1) of the second portion 35 from the tip (the outermost tip) of the second portion 35.

[0022] The contact 40 is attached at the tip of the second portion 35 so as to be perpendicular to the axial direction of the second portion 35. In the example shown in FIG. 1, the contact 40 is attached so as to be perpendicular to the Y-direction side with respect to the axial direction of the second portion 35. Specifically, the contact 40a of the measurement arm 11a is attached to the +Y direction side, and the contact of the measurement arm 11b is attached to the -Y direction side. However, the contact 40 may be attached obliquely with respect to the axial direction of the second portion 35. The shape of the contact 40 is not particularly limited, but in the example shown in FIG. 1, it is formed in a hemispherical shape.

[0023] The measurement head 12 rotatably supports each first end of the pair of measurement arms 11a and 11b. The measurement head 12 measures the inner diameter of the measurement hole 100. For example, the measurement head 12 has sensors that detect the displacements of the two contacts 40a and 40b, and measures the inner diameter of the measurement hole 100 based on the detection results of the sensors.

[0024] When measuring the inner diameter of the measurement hole 100 of the workpiece W held by the chuck device 20, the inner diameter measuring device 10 rotates the closed measurement arm 11a and the measurement arm 11 so that the contacts 40a and 40b contact the inner diameter surface 110 of the measurement hole 100. Hereinafter, the closed measurement arm 11a and the measurement arm 11 may be referred to as the "closed state". Also, the state where the contacts 40a and 40b contact the inner diameter surface 110 of the measurement hole 100 may be referred to as the "open state".

[0025] The displacement of the contacts 40a and 40b from the closed state to the open state corresponds to the inner diameter of the measurement hole 100. Therefore, the inner diameter measuring device 10 measures the inner diameter of the measurement hole 100 by detecting the displacement of the contacts 40a and 40b from the closed state to the open state with one or more sensors. Note that the measuring head 12 only needs to be able to directly or indirectly detect the displacement of the contacts 40a and 40b, and the type of the sensor and the detection method thereof are not particularly limited. For example, when the contacts 40a and 40b contact the inner diameter surface 110 of the measurement hole 100, the measuring head 12 may output a signal corresponding to the displacement of the contacts 40a and 40b to the outside as the inner diameter of the measurement hole 100.

[0026] The chuck device 20 holds the workpiece W. The chuck device 20 has, for example, three claw portions 21 for gripping the workpiece W and a main body portion 22 that is held so as to be movable in the radial direction with respect to the central axis Ck of the chuck device 20. The illustrated central axis Ck is an axis parallel to the Z direction. The three claw portions 21 are provided at equal intervals along a predetermined circumferential direction around the central axis Ck.

[0027] Each claw portion 21 is arranged side by side around the axis of the central axis Ck. Each claw portion 21 moves forward and backward between an open position and a closed position along the radial direction. When each claw portion 21 is in the open position, a space K (FIG. 3) into which the workpiece W can be inserted is formed inside the three claw portions 21. After the workpiece W is inserted into the space K and each claw portion 21 is moved radially inward (in the direction of the closed position), the workpiece W is held immovably by the three claw portions 21.

[0028] Here, in a state where the workpiece W is held by the chuck device 20, the central axis Cw of the workpiece W coincides with the central axis Ck of the chuck device 20. That is, the chuck device 20 is a so-called centering (centering) type chuck that holds the workpiece W in a state where the central axis Cw of the workpiece W (measurement hole 100) coincides with the central axis Ck of the chuck device 20. Note that making the central axis Cw of the workpiece W (measurement hole 100) coincide with the central axis Ck of the chuck device 20 may be referred to as "centering".

[0029] Hereinafter, the inner diameter measurement method according to the present embodiment will be described with reference to FIGS. 3 to 7.

[0030] FIG. 3 is a diagram showing the inner diameter measuring device 10 in the initial state. As shown in FIG. 3, in the initial state, the inner diameter measuring device 10 is arranged with a pair of measuring arms 11a and 11b in a closed state (closed state).

[0031] Specifically, each first portion 30 is disposed above the main body portion 22 of the chuck device 20 and at a position lower than each claw portion 21 so as to extend along the Z direction which is the first direction. Since each first portion 30 is inserted between the two claw portions 21, it does not interfere with the claw portions 21. When viewed from the Y direction, the first portion 30 extends in the +X direction until the second end portion of each first portion 30 is located on the central axis Ck.

[0032] Also, in the initial state, each second portion 35 extends along the +Z direction within the space K. Further, in the initial state, the central position CP (FIG. 6) between the axes of each second portion 35 in the closed state is located on the central axis Cw.

[0033] When the inner diameter measuring device 10 is in the initial state, an operator or a loader device inserts the workpiece W into the space K of the chuck device 20 (FIG. 4). When the workpiece W is inserted into the space K, the chuck device 20 centers and holds the workpiece W by moving each claw portion 21 radially inward (FIG. 5). That is, when the chuck device 20 holds the workpiece W, the workpiece W is fixed in a state where the central axis Cw of the workpiece W coincides with the central axis Ck of the chuck device 20.

[0034] When the workpiece W is held by the chuck device 20, a pair of contacts 40a and 40b are arranged inside the workpiece W. That is, the contacts 40a and 40b are inserted into the measurement holes 100 of the workpiece W. In this state, since the contacts 40a and 40b are located above the lower end of the inner diameter surface 110, when the measurement arms 11a and 11b rotate on the horizontal plane, the contacts 40a and 40b come into contact with the inner diameter surface 110 of the measurement hole 100.

[0035] As described above, as shown in FIG. 6, the chuck device 20 aligns the central axis Ck passing through the central position CP between the axes of the pair of second portions 35 and parallel to the second direction with the central axis Cw of the measurement hole 100, and holds the workpiece W so that the pair of contacts 40a and 40b are arranged inside the workpiece W.

[0036] In the state where the workpiece W is held by the chuck device 20 (FIG. 6), the internal diameter measuring device 10 shifts the pair of closed measurement arms 11a and 11b to the open state (FIG. 7). Specifically, as shown in FIG. 7, the internal diameter measuring device 10 opens the pair of measurement arms 11a and 11b until the contacts 40a and 40b come into contact with the inner peripheral surface. Opening the pair of measurement arms 11a and 11b means, for example, rotating them in the first rotation direction and rotating the measurement arm 11b in the second rotation direction opposite to the first rotation direction. The internal diameter measuring device 10 measures the displacement amounts of the contacts 40a and 40b displaced from the closed state to the open state as the inner diameter of the measurement hole 100.

[0037] As described above, the internal diameter measuring device 10 according to the present embodiment can measure the hole diameter of the measurement hole 100 without using an internal diameter guide. With such a configuration, since it is not necessary to insert an internal diameter guide into the measurement hole 100, even if the size of the measurement hole 100 changes, it does not take time to replace the internal diameter guide. Further, in the internal diameter measuring device 10 according to the present embodiment, since no internal diameter guide is used, it is possible to measure even a smaller measurement hole 100. Therefore, even if the size of the measurement hole 100 changes, the internal diameter measuring device 10 can continue to be used, and the time and effort required to replace it with an internal diameter measuring device suitable for the size of the measurement hole 100 can be reduced.

[0038] Here, in an inner diameter measuring device using an inner diameter guide as in the prior art, in order to ensure a sufficient space for the measuring arm to open and close, the size of the inner diameter guide is made as large as possible. However, when the size of the inner diameter guide is increased, the clearance between the inner diameter surface 110 of the measuring hole 100 and the inner diameter guide becomes very narrow. As a result, when the inner diameter guide is inserted into the measuring hole 100, the inner diameter guide may damage the inner diameter surface 110 of the measuring hole 100. Since the inner diameter measuring device 10 according to the present embodiment can measure the hole diameter of the measuring hole 100 without using an inner diameter guide, when the work W is placed on the chuck device 20 by the loader device and the measuring arm 11 is inserted into the measuring hole 100, it is possible to prevent the inner diameter surface 110 of the measuring hole 100 from being damaged by the inner diameter guide.

[0039] The above embodiment discloses the following configuration. (Configuration 1) An inner diameter measuring device 10 that measures the inner diameter of the measuring hole 100 by bringing the contact 40 into contact with the inner diameter surface 110 of the measuring hole 100 of the work W, having a pair of openable and closable measuring arms 11, each measuring arm 11 has a first portion 30 extending in a first direction, and a second portion 35 that bends and extends in a second direction intersecting the first direction from the end of the first portion 30, and a contact 40 is provided at the tip of the second portion 35. The inner diameter measuring device 10. (Configuration 2) The second direction is a direction orthogonal to the first direction, The inner diameter measuring device 10 according to Configuration 1. (Configuration 3) comprising a measuring head 12 that rotatably supports a pair of measuring arms 11, the first portion 30 has the first end of the first portion 30 rotatably supported by the measuring head and protruding and extending in the first direction from the measuring head 12, the second portion 35 extends in the second direction from the second end of the first portion 30, The internal diameter measuring device 10 described in Configuration 1 or Configuration 2. (Configuration 4) A chuck device 20 having a plurality of claw portions 21 arranged side by side around the axis of the first central axis (central axis Ck), An internal diameter measuring device 10 that measures the internal diameter of the measurement hole 100 by bringing a contact into contact with the inner diameter surface 110 of the measurement hole 100 of the workpiece W held by the chuck device 20, The chuck device 20 holds the workpiece W in a state where the first central axis coincides with the second central axis, which is the central axis Cw of the measurement hole 100, by moving the plurality of claw portions 21 inward in the radial direction. The internal diameter measuring device 10 has a pair of openable and closable measuring arms 11. Each measuring arm 11 A first portion 30 extending in the first direction, A second portion 35 that bends and extends in a second direction intersecting the first direction from the end of the first portion 30, An internal diameter measuring system IDMS in which a contact 40 is provided at the tip of the second portion 35. (Configuration 5) The second direction is a direction perpendicular to the first direction and parallel to the axial direction of the first central axis. The internal diameter measuring device 10 or the internal diameter measuring system IDMS according to any one of Configurations 1 to 4. (Configuration 6) The chuck device 20 has a main body portion 22 that holds the plurality of claw portions 21 movably in the radial direction. The first portion 30 extends along the first direction at a position above the main body portion 22 and lower than the plurality of claw portions 21. The second portion 35 extends vertically upward from the end of the first portion 30. When the workpiece W is held by the chuck device 20, the tip of the second portion 35 is inserted into the measurement hole 100 from below the workpiece W. The internal diameter measuring device 10 or the internal diameter measuring system IDMS according to any one of Configurations 1 to 5.

[0040] One or more of the requirements described in the above-described embodiments and the like may be omitted. Further, the requirements described in the above-described embodiments and the like can be combined as appropriate. Also, the execution order of each procedure shown in this embodiment can be realized in any order as long as the results of the previous procedure are not used in the subsequent procedure. Further, regarding the operations in the above-described embodiments, even if they are described for convenience using "first", "next", "subsequently", etc., it is not essential to carry them out in this order.

Description of Reference Numerals

[0041] 10... Inner diameter measuring device, 11... Measuring arm, 20... Chuck device, 30... First part, 35... Second part, 40... Contact, IDMS... Inner diameter measurement system

Claims

1. An internal diameter measuring device for measuring the internal diameter of a measurement hole by bringing a contact into contact with the inner diameter surface of the measurement hole of a workpiece, comprising: a pair of openable and closable measurement arms; each of the measurement arms includes: a first portion extending in a first direction; and a second portion bent and extending in a second direction intersecting the first direction from an end of the first portion, wherein the contact is provided at a tip of the second portion. An internal diameter measuring device.

2. The internal diameter measuring device according to claim 1, wherein the second direction is a direction orthogonal to the first direction.

3. The internal diameter measuring device according to claim 1, further comprising a measurement head that rotatably supports the pair of measurement arms, wherein the first portion has a first end of the first portion rotatably supported by the measurement head and protruding and extending in the first direction from the measurement head, and the second portion extends in the second direction from a second end of the first portion.

4. An internal diameter measuring system having a chuck device having a plurality of claw portions arranged side by side around the axis of a first central axis, and an internal diameter measuring device for measuring the internal diameter of a measurement hole of a workpiece held by the chuck device by bringing a contact into contact with the inner diameter surface of the measurement hole, wherein the chuck device holds the workpiece in a state where the first central axis coincides with a second central axis that is the central axis of the measurement hole by moving the plurality of claw portions radially inward, and the internal diameter measuring device has a pair of openable and closable measurement arms, each of the measurement arms includes: a first portion extending in a first direction; and a second portion bent and extending in a second direction intersecting the first direction from an end of the first portion, wherein the contact is provided at a tip of the second portion. An internal diameter measuring system.

5. The internal diameter measuring system according to claim 4, wherein the second direction is a direction orthogonal to the first direction and parallel to the axial direction of the first central axis.

6. The internal diameter measuring system according to claim 5, wherein the chuck device has a main body portion that movably holds the plurality of claw portions in the radial direction, the first portion extends along the first direction at a position higher than the main body portion and lower than the plurality of claw portions, the second portion extends vertically upward from an end of the first portion, and when the workpiece is held by the chuck device, the tip of the second portion is inserted into the measurement hole from below the workpiece. ​ ​ ​

Citation Information

Patent Citations

  • Measuring method using size measuring instrument with guide

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