Inner diameter measurement system and inner diameter measurement method

Abstract

To provide an inner diameter measurement system and an inner diameter measurement method capable of measuring a measurement hole without using an inner diameter guide.SOLUTION: An inner diameter measurement system IDMS includes: a chuck device 20 having a plurality of pawl parts 21 aligned and arranged around an axial circumference of a first central axis (central axis Ck); and an inner diameter measurement device 10 configured to cause a contact piece to contact with an inner diameter surface 110 of a measurement hole 100 of a work piece W held by the chuck device 20 to measure an inner diameter of the measurement hole 100. The chuck device 20 holds the work piece W in a state where the first central axis and a second central axis being a central axis Cw of the measurement hole 100 are aligned, through moving the plurality of pawl parts 21 inward in a radial direction.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to an inner diameter measurement system and an inner diameter measurement method.

Background Art

[0002] An inner diameter measuring device 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 is known (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 in the inner diameter guide. 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 measurement system and an inner diameter measurement method that can measure a measurement hole without using an inner diameter guide.

Means for Solving the Problems

[0006] The inner diameter measurement 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 measurement 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 and a second central axis, which is the central axis of the measurement hole, are aligned by moving the plurality of claw portions radially inward.

[0007] The inner diameter measurement method according to an aspect of the present invention is an inner diameter measurement method for measuring the inner diameter of a measurement hole of a workpiece, including holding the workpiece in a state where a first central axis, which is the central axis of a chuck device, and a second central axis, which is the central axis of the measurement hole, are aligned by moving a plurality of claw portions of the chuck device radially inward, and measuring the inner diameter of the measurement hole by bringing a contact into contact with the inner diameter surface of the measurement hole of the workpiece held by the chuck device.

Effect of the Invention

[0008] The inner diameter measurement 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 measurement 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 and a second central axis, which is the central axis of the measurement hole, are aligned by moving the plurality of claw portions radially inward. Further, the inner diameter measurement method according to an aspect of the present invention includes holding the workpiece in a state where a first central axis, which is the central axis of a chuck device, and a second central axis, which is the central axis of the measurement hole, are aligned by moving a plurality of claw portions of the chuck device radially inward, and measuring the inner diameter of the measurement hole by bringing a contact into contact with the inner diameter surface of the measurement hole of the workpiece held by the chuck device. With such a configuration, the inner diameter of the measurement hole can be measured without using an inner diameter guide, and the labor of replacing the inner diameter guide can be reduced.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Mode for Carrying Out the Invention

[0010] 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 explanations may be omitted. Also, the shape and size of elements in the drawings may be exaggerated for clearer explanation, and thus may be different in shape and dimensions from the actual product.

[0011] 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. Also, the direction perpendicular to the XY plane is denoted as the Z direction.

[0012] FIG. 1 is a plan view of the inner diameter measurement system IDMS according to this embodiment. FIG. 2 is a side sectional view of the inner diameter measurement system IDMS according to this embodiment. The inner diameter measurement system IDMS includes an inner diameter measuring device (bore gauge) 10 and a chuck device 20.

[0013] The inner diameter measuring device 10 measures the inner diameter of a hole formed in a workpiece W. In the example shown in FIGS. 1 and 2, the shape of the workpiece W is cylindrical, but it may be a shape other than cylindrical. The inner diameter measuring device 10 is fixed to, for example, a machine tool or the like. Hereinafter, the hole whose inner diameter is measured by the inner diameter measuring device 10 may be referred to as a "measurement hole 100".

[0014] The inner diameter measuring device 10 includes a pair of measurement arms 11 and a measurement head 12. When distinguishing each of the pair of measurement arms 11, one measurement arm 11 is referred to as a "measurement arm 11a", and the other measurement arm 11 is referred to as a "measurement arm 11b". Also, for the purpose of distinguishing a plurality of the same type of components from each other, an "a" may be added to the end of the symbol of each component of the measurement arm 11a, and a "b" may be added to the end of the symbol of each component of the measurement arm 11b.

[0015] The measurement 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.

[0016] 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 portion of the first portion 30 is pivotally supported by the measurement head 12. In the example shown in FIG. 1, the first end portion of the first portion 30 is pivotally supported so as to be rotatable about an axis parallel to the Z direction as a support axis.

[0017] The second portion 35 extends by bending in the second direction from the second end portion 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 measurement 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.

[0018] 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 different from the first portion 30 or may be a member integral with the first portion 30. Note that the shape of the measurement arm 11 does not necessarily have to be L-shaped. That is, the second direction is not limited to a direction orthogonal to the first direction and may be any direction that intersects the first direction.

[0019] 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 foremost end) of the second portion 35.

[0020] 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. Note that 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.

[0021] The measurement head 12 rotatably supports the first ends 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.

[0022] 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 measuring arm 11a and the measuring arm 11 so that the contacts 40a and 40b contact the inner diameter surface 110 of the measurement hole 100. Hereinafter, the closed measuring arm 11a and the measuring arm 11 may be referred to as the "closed state". Further, the state in which the contact 40a and the contact 40b are in contact with the inner diameter surface 110 of the measurement hole 100 may be referred to as the "open state".

[0023] The displacements of the contacts 40a and 40b from the closed state to the open state correspond 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 displacements of the contacts 40a and 40b from the closed state to the open state with one or more sensors. The measuring head 12 only needs to be able to directly or indirectly detect the displacements 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 displacements of the contacts 40a and 40b to the outside as the inner diameter of the measurement hole 100.

[0024] 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.

[0025] 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, when 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.

[0026] 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 (centrifugal) 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".

[0027] Hereinafter, the inner diameter measurement method according to the present embodiment will be described with reference to FIGS. 3 to 7.

[0028] FIG. 3 is a diagram showing the inner diameter measuring device 10 in an 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).

[0029] 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. Note that 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.

[0030] Also, in the initial state, each second portion 35 extends along the +Z direction in 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.

[0031] When the internal diameter measuring device 10 is in the initial state, the operator or the 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 inward in the radial direction (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.

[0032] In a state where the workpiece W is held by the chuck device 20, a pair of contacts 40a, 40b are arranged inside the workpiece W. That is, the contacts 40a, 40b are inserted into the measurement holes 100 of the workpiece W. In this state, since the contacts 40a, 40b are located above the lower end of the inner diameter surface 110, when the measurement arms 11a, 11b rotate on the horizontal plane, the contacts 40a, 40b come into contact with the inner diameter surface 110 of the measurement holes 100.

[0033] As shown in Fig. 6, in this way, 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 holes 100, and holds the workpiece W so that a pair of contacts 40a, 40b are arranged inside the workpiece W.

[0034] When the workpiece W is held by the chuck device 20 (Fig. 6), the internal diameter measuring device 10 shifts a pair of closed measurement arms 11a, 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, 11b until the contacts 40a, 40b come into contact with the inner peripheral surface. Opening the pair of measurement arms 11a, 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 amount of the displaced contacts 40a and 40b from the closed state to the open state as the inner diameter of the measurement holes 100.

[0035] Thus, the inner diameter measuring device 10 according to this embodiment can measure the hole diameter of the measurement hole 100 without using an inner diameter guide. With such a configuration, since it is not necessary to insert the inner diameter guide into the measurement hole 100, even if the size of the measurement hole 100 changes, there is no need to spend the effort to replace the inner diameter guide. Further, in the inner diameter measuring device 10 according to this embodiment, since no inner 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 inner diameter measuring device 10 can continue to be used, and the effort of replacing it with an inner diameter measuring device suitable for the size of the measurement hole 100 can be reduced.

[0036] 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 measurement hole 100 and the inner diameter guide becomes very narrow. As a result, when the inner diameter guide is inserted into the measurement hole 100, the inner diameter guide may damage the inner diameter surface 110 of the measurement hole 100. Since the inner diameter measuring device 10 according to this embodiment can measure the hole diameter of the measurement 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 measurement hole 100, it is possible to prevent the inner diameter surface 110 of the measurement hole 100 from being damaged by the inner diameter guide.

[0037] The above embodiment discloses the following configuration. (Configuration 1) An inner diameter measuring device 10 that measures the inner diameter of the measurement hole 100 by bringing the contact 40 into contact with the inner diameter surface 110 of the measurement 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 from the end of the first portion 30 in a second direction intersecting the first direction, and the 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 internal 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 a first end of the first portion 30 rotatably supported by the measuring head, and extends protruding 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 according to 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 of the workpiece W held by the chuck device 20 by bringing a contact into contact with the inner diameter surface 110 of the measurement hole 100, 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 radially inward. 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, 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. 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 orthogonal 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 a plurality of claw portions 21 movably in the radial direction. The first portion 30 is above the main body portion 22 and extends along the first direction at a position lower than the plurality of claw portions 21. The second part 35 extends vertically upward from the end of the first part 30, When the workpiece W is held by the chuck device 20, the tip of the second part 35 is inserted into the measurement hole 100 from below the workpiece W, and the internal diameter measuring device 10 or the internal diameter measuring system IDMS according to any one of Configurations 1 to 5.

[0038] 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 the present embodiment can be realized in any order as long as the result of the previous procedure is not used in the subsequent procedure. Also, 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 perform them in this order.

Explanation of Reference Numerals

[0039] 10... internal diameter measuring device, 11... measuring arm, 20... chuck device, 30... first part, 35... second part, 40... contact, IDMS... internal diameter measuring system

Claims

1. 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 configured to measure 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, and having the chuck device holds the workpiece in a state where the first central axis, which is the central axis of the chuck device, and the second central axis, which is the central axis of the measurement hole, are aligned by moving the plurality of claw portions radially inward; an inner diameter measurement system.

2. An inner diameter measurement method for measuring the inner diameter of a measurement hole of a workpiece, comprising: holding the workpiece in a state where a first central axis, which is the central axis of the chuck device, and a second central axis, which is the central axis of the measurement hole, are aligned by moving a plurality of claw portions of the chuck device radially inward; and measuring the inner diameter of the measurement hole by bringing a contact into contact with the inner diameter surface of the measurement hole of the workpiece held by the chuck device. An inner diameter measurement method including the above.

Images