JPH08152318A - Inner diameter measuring apparatus - Google Patents

Abstract

PURPOSE: To provide an apparatus for measuring the inner diameter quickly and accurately over the entire circumference. CONSTITUTION: The inner diameter measuring apparatus comprises a rotary shaft supporting member 2 being fixed to a rotary shaft 5 supported by a tubular material 10 while substantially aligning the axis, first and second movable members 3, 4 rotating about the axis along with the rotary shaft 5 while being supported by the supporting member 2 slidingly in the direction perpendicular to the axis, members 6, 7 for urging the first and second movable members 3, 4 forward and rearward resiliently in the diametral direction of the tubular material 10, and a sensor 8 for detecting the relative replacement between the first and second movable members 3, 4. The first and second movable members 3, 4 are brought into resilient contact, at each end, with the inner circumferential face of the tubular material 10 thus measuring the inner diameter of the tubular material 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inner diameter measuring device.

[0002]

2. Description of the Related Art Conventionally, circumferential welding has been performed to connect pipe materials. In this circumferential welding, it is necessary that the inner diameters of the pipe materials to be joined are substantially the same. In order to control the inner diameter of the pipe material to be welded around the circumference, the average diameter and the elliptic amount are measured. An inside micrometer or a caliper is known as a conventional mechanical inner diameter measuring device. In this method, the inner diameter of 8 to 32 equidistant parts of the circumference was manually measured, and the average diameter and the amount of ellipse were calculated from the values.

However, in such a conventional inner diameter measuring apparatus, the number of measuring points must be increased in order to perform an accurate measurement, not only a long time is required for the measurement, but also the maximum diameter is simply set. It just measures. That is, as shown in FIG. 5, the measurement surface 110a at one end of the inside micrometer 110 is fixed at a predetermined position on the inner peripheral surface of the pipe material 100, and the measurement surface 110b at the other end is arranged along the inner peripheral surface of the pipe material 100. The maximum length is measured while moving in the circumferential direction, and this maximum length is used as the diameter, so it cannot be said that the diameter is accurately measured. In addition, there is a technical problem that the measurement of the locally deformed portion is likely to be excluded. For example, as shown in FIG. 5, in the pipe material 100 in which the stainless overlay layer 100b is formed on the inner periphery, the inner peripheral surface 1 around the welded portion 102 welded in the central axis direction.
00a has a recess 100c due to local heat shrinkage associated with welding.
However, it was difficult to accurately measure the recess 100c portion, and it could not be said that the maximum diameter and the minimum diameter were accurately measured.

[0004]

The present invention has been made in view of such conventional technical problems, and has the following structure. According to the structure of the invention of claim 1, the rotating shaft supporting member 2 is attached to the rotating shaft 5 supported by the cylindrical material 10 so that the central axis lines are substantially aligned with each other, and the rotating shaft supporting member 2 is arranged in the direction orthogonal to the central axis line. The first and second movable members 3 and 4, which are slidably supported and rotate around the central axis together with the rotation shaft 5, and the first and second movable members 3 and 4, are made of a cylindrical material 10.
Urging members 6 and 7 for elastically urging forward and backward in the diametrical direction of
And a sensor 8 for detecting the relative displacement amount of the first and second movable members 3 and 4, with each end of the first and second movable members 3 and 4 on the inner peripheral surface of the cylindrical material 10. The inner diameter measuring device is characterized in that the inner diameter of the cylindrical material 10 is measured by elastically contacting it. According to the configuration of the invention of claim 2, the first movable member 3
2. The inner diameter measuring apparatus according to claim 1, wherein the rotary shaft support member 2 is slidably supported, and the second movable member 4 is slidably supported by the first movable member 3.

[0005]

According to the first aspect of the invention, the rotating shaft 5 is supported by the cylindrical material 10 so that the central axes thereof are substantially aligned with each other.
When is driven to rotate, the rotary shaft support member 2 and the first and second movable members 3 and 4 rotate integrally. As a result, the first and second movable members 3 and 4 that are elastically biased in the diametrical direction of the cylindrical material 10 by the biasing members 6 and 7 increase or decrease the diameter of the cylindrical material 10. Therefore, since it expands and contracts, the relative displacement of the first and second movable members 3 and 4 due to the expansion and contraction is detected by the sensor 8. Then, by rotating the rotary shaft 5 and the inner diameter measuring device half a turn (180 ° rotation), the inner diameter of the cylindrical material 10 over the entire circumference can be continuously measured.

Since the rotating shaft 5 is supported by the cylindrical material 10, the rotating shaft 5, which is the center of the inner diameter measuring device, does not move with respect to the cylindrical material 10 during the measurement, and the measurement accompanying this movement does not occur. It is hard to make an error. The average inner diameter and the amount of ellipse can be obtained from the inner diameter of the entire circumference of the cylindrical material 10. In the cylindrical material 10 having a diameter of 300 mm or more,
In the measurement performed to confirm the quality of the inner diameter in the circumferential welding for connecting the pair of cylindrical materials 10, the rotating shaft 5
Also, a deviation of several millimeters between the center axis of the inner diameter measuring device and the center axis of the cylindrical material 10 is allowed. In this way, the measurement by the inner diameter measuring device is performed while each end of the first and second movable members 3 and 4 moves along the inner surface of the cylindrical material 10, so that the first and second movable members 3 are , 4 can be accurately entered, the recesses on the inner surface of the cylindrical material 10 can be accurately measured.

According to the invention of claim 2, the cylindrical material 10
When measuring the inner diameter of the first movable member 3, the first movable member 3 slides with respect to the rotating shaft support member 2, and the second movable member 4 slides with respect to the first movable member 3.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 4 show an embodiment of the present invention. In the figure, reference numeral 1 indicates an inner diameter measuring device. The inner diameter measuring device 1 includes a rotating shaft supporting member 2, first and second movable members 3, 4
With. The rotary shaft support member 2 includes a dovetail 2a and a dovetail groove 3
It is slidable in the longitudinal direction of the first movable member 3 by the concavo-convex engagement with c. The rotary shaft 5 is detachably attached to the rotary shaft support member 2, and is fixed by a set screw 12 as shown in FIG.

The first movable member 3 is moved in one direction with respect to the rotary shaft supporting member 2 by a spring 7 which is a biasing member.
That is, the first movable member 3 is elastically biased toward one side in the longitudinal direction. A roller 3a is rotatably supported at one end of the first movable member 3, and a second movable member 4 is non-rotatably and slidably inserted in a longitudinal direction into a rectangular hole 3b at the other end. . A roller 4a is rotatably supported at the other end of the second movable member 4 and is directed toward the other side in the longitudinal direction of the first movable member 3 by a spring 6 which is a biasing member housed in the hole 3b. Elastically biased. Thus, the first and second movable members 3 and 4 are slidably supported in the direction orthogonal to the central axis of the rotary shaft 5 and are elastically biased forward and backward by the springs 6 and 7. . The center axis of the support shaft of each roller 3a, 4a is parallel to the center axis of the rotary shaft 5.

Then, the first movable member 3 and the second movable member 4
A sensor 8 for detecting a relative displacement amount in the longitudinal direction is interposed between and. The sensor 8 can be either a contact type (potentiometer) or a non-contact type (eddy current type displacement sensor, laser interference type sensor), and is inserted at an appropriate position so that the relative displacement amount can be detected. In particular, according to the eddy current type displacement sensor, an eddy current generated in the conductor member is generated due to a change in the gap between the magnetic flux generating coil attached to the first movable member 3 and the second movable member 4 which is the conductor member. The relative displacement between the first movable member 3 and the second movable member 4 is measured by utilizing the change in the impedance of the coil, which has advantages such as non-contact, high frequency response, high stability, and good resolution. is there.

The inside diameter measuring device 1 as described above is provided as a supporting device 1.
1 is rotatably supported in the pipe material 10 which is a cylindrical material, and the central axis of the rotary shaft 5 is substantially aligned with the central axis of the pipe material 10. The support device 11 for the rotating shaft 5 of the inner diameter measuring device 1 will be described with reference to FIGS.

The rotating shaft 5 has circular first and second fixing plates 2
The bearings 23 are rotatably supported by the bearings 1 and 22, respectively, and the rotary shaft support member 2 is detachably fixed to the tip of the rotary shaft 5 (the left end in FIG. 4) by a set screw 12. . The rotating shaft 5 is rotationally driven by a motor 40 attached to the circular third fixing plate 29 via a speed reducer 41 and a coupling 39. The rotational position of the rotary shaft 5 is detected by the encoder 26 fixed to the second fixed plate 22. Actually, the rotational position of the gear 25 meshing with the gear 24 fixed to the rotary shaft 5 is detected by the encoder 26.
The first to third fixing plates 21, 22 and 29 are fixed together with a circular fourth fixing plate 52, which will be described later, by a plurality of fixing shafts 26 at predetermined intervals on the same axis line. 4 A fixing mechanism 42 is provided outside the fixing plates 21, 22, 29, and 52.
Is provided.

Three or more fixing mechanisms 42 are provided between the first fixing plate 21 and the circular fifth fixing plate 53 (three in this embodiment).
The parallel link mechanism is formed. Fifth fixing plate 5
3 is movably supported by a screw shaft 55, which is rotatably supported by a support portion 63 on the fourth fixing plate 52. That is, the front end portion of the screw shaft 55 is rotatably attached to the fourth fixing plate 52 by aligning the central axis with the rotating shaft 5, and
The fifth fixing plate 53 is fixed to the nut member 54 screwed to the intermediate portion of the above, and the handle 62 is fixed to the rear end of the screw shaft 55. Reference numeral 59 is a set screw that fixes the nut member 54 to the screw shaft 55 and fixes the distance between the fourth fixing plate 52 and the fifth fixing plate 53.

Further, each parallel link mechanism includes a first fixing plate 2
A pair of short links 45 of equal length whose inner ends are swingably pin-coupled to the first and fifth fixing plates 53 via mounting members 46 and outer ends of the pair of short links 45 are connected to each other. As shown in FIG. 4, the short link 45 and the like are provided between the rear end of one long link 47 and the fourth fixing plate 52. Long short link 45
The pin a is swingably connected. A plurality of rollers 70 are rotatably supported by the two long links 47, and the remaining one long link 47 including the short links 45a is provided.
A getter member 72 is attached to the central portion of the via a spring 71. The first fixing plate 21 and the fifth of the mounting member 46
By changing the mounting position on the fixed plate 53, each long link 4
The outer diameter of 7 can be changed.

Then, the screw shaft 5 is provided by the handle 62.
When 5 is rotated to move the nut member 54 and the fifth fixing plate 53 forward, the short links 45, 45a gradually stand up,
Each long link 47 moves in the outer diameter direction. When the nut member 54 and the fifth fixing plate 53 are retracted, the short links 45, 45a gradually tilt and the long links 47 move in the inner diameter direction. Reference numeral 60 is a counter attached to the tip of the screw shaft 55.
The inner diameter value of is displayed roughly.

Next, the operation of the above embodiment will be described. The rotary shaft supporting member 2 of the inner diameter measuring device 1 is fixed to the rotary shaft 5 of the supporting device 11 with a set screw 12. The first and second movable members 3 and 4 of the inner diameter measuring device 1 are inserted into the pipe material 10 together with the supporting device 11 in a state where the spring 6 is compressed and the spring 7 is expanded to reduce the entire length. In the pipe material 10, the supporting device 11 moves while the roller 70 rolls, and the roller 3 of the inner diameter measuring device 1 moves.
a and 4a slide on the inner surface of the pipe material 10.

When the inner diameter measuring device 1 reaches the measurement position, the handle 62 and the screw shaft 55 are rotated to advance the nut member 54 and the fifth fixing plate 53. This allows
Each short link 45, 45a gradually stands up and each long link 4
7 moves in the outer diameter direction, and the getter member 72 causes the spring 71 to move.
Is elastically pressed against the inner surface of the pipe material 10 via
The support device 11 is fixed. Thus, the rotary shaft 5 can be installed at substantially the center of the pipe material 10. The outline of the inner diameter value of the pipe material 10 with the support device 11 fixed is detected by the counter 60 and displayed on the outside.

From this state, the rotary shaft 5 is rotated by the motor 40.
When is driven to rotate, the rotary shaft support member 2 and the first and second movable members 3 and 4 rotate integrally. When the first and second movable members 3 and 4 rotate, the rollers 3a and 4a move the pipe material 10
Rolls on the inside. As a result, the first and second movable members 3 and 4 elastically biased in the diameter direction of the pipe material 10 by the springs 6 and 7 expand and contract along the diameter of the pipe material 10. The relative displacement of the first and second movable members 3 and 4 can be detected by the sensor 8. The value detected by the sensor 8 is taken out to the outside by a lead wire (not shown). Since the rotation drive angle of the rotary shaft 5 and the inner diameter measuring device 1 by the motor 40 is detected by the encoder 26,
The inner diameter of the pipe material 10 at a position corresponding to the rotational drive angle of the inner diameter measuring device 1 can be measured by the sensor 8. Rotating shaft 5
And, if the inner diameter measuring device 1 is rotated by half (180 ° rotation), the diameter over the entire circumference is continuously measured.

Since the inner diameter measuring device 1 is supported by the supporting device 11 installed in the pipe material 10, the rotating shaft 5 which is the center of the inner diameter measuring device 1 moves with respect to the pipe material 10 during the measurement. Therefore, the measurement error due to this movement is unlikely to occur. The average inner diameter and the elliptic amount can be obtained from the inner diameter of the entire circumference of the pipe material 10. The diameter is 300m
In the pipe material 10 of m or more, in the measurement performed to confirm the quality of the inner diameter in the circumferential welding for connecting the pair of pipe materials 10, the center axis of the rotating shaft 5 and the inner diameter measuring device 1 and the pipe material 10 are measured. A deviation of a few millimeters from the center axis of the is not a practical problem. When the inner diameter measuring device 1 is used for the pipe materials 10 having greatly different inner diameters, the mounting positions of the mounting members 46 on the first fixing plate 21, the fourth fixing plate 52, and the fifth fixing plate 53 are changed, The outer diameter of each long link 47 is appropriately maintained. As described above, in the measurement by the inner diameter measuring device 1, the rollers 3a and 4a are connected to the pipe material 1
Since it is continuously performed while rolling on the inner surface of the pipe member 0, if the size of the rollers 3a and 4a is such that it can enter, the pipe member 10
It is possible to accurately measure the recess on the inner surface of the.

By the way, in the above embodiment, the roller 3
By omitting a and 4a, the bearing material used for the sliding friction surface of the slide bearing is fixed to each end of the first and second movable members 3 and 4, and each of the first and second movable members 3 and 4 is fixed. Pipe material 1 at the end
It is also possible to measure the inner diameter of the pipe material 10 while sliding the inner surface of 0. In addition, the first and second movable members 3,
4 may be elastically biased in the diametrical direction of the pipe material 10 in the forward and reverse directions, and the rotary shaft support member 2 may have the first and second movable members 3, 4.
4 are slidably provided, and the first and second movable members 3,
It is also possible to elastically bias in the opposite direction by a biasing member such as a spring or rubber interposed between the four.

[0021]

As can be understood from the above description,
According to the present invention, the inner diameter of a cylindrical material can be measured quickly and accurately over the entire circumference by an inner diameter measuring device having a simple structure, and a local recess can also be measured.

[Brief description of drawings]

FIG. 1 is a side view showing a partially cut-away view of an inner diameter measuring device according to an embodiment of the present invention.

FIG. 2 is a rear view showing the inner diameter measuring device.

FIG. 3 is a front view showing the arrangement of the inner diameter measuring device and the supporting device.

FIG. 4 is a sectional view taken along line III-III of FIG.

FIG. 5 is a diagram showing a conventional example.

[Explanation of symbols]

1: Inner diameter measuring device, 2: Rotating shaft supporting member, 3: First movable member, 4: Second moving member, 5: Rotating shaft, 6, 7: Spring (biasing member), 8: Sensor, 10: Pipe Material (cylindrical material), 11: support device.

Claims (2)

[Claims] 1. A rotary shaft support member (2) attached to a rotary shaft (5) supported by a cylindrical material (10), and a central shaft line of the rotary shaft support member (2), which are substantially aligned with each other. Is slidably supported in a direction orthogonal to the first and second movable members (3, 3) that rotate around the central axis together with the rotating shaft (5).
4), an urging member (6, 7) for elastically urging the first and second movable members (3, 4) in the diametrical direction of the cylindrical material (10) in the forward and reverse directions; And a sensor (8) for detecting the relative displacement amount of the two movable members (3, 4), and each end of the first and second movable members (3, 4) has an inner circumference of the cylindrical material (10). An inner diameter measuring device, characterized by elastically contacting a surface to measure the inner diameter of a cylindrical material (10). 2. A first movable member (3) is slidably supported by a rotary shaft support member (2), and a second movable member (4) is slidably supported by a first movable member (3). The inner diameter measuring device according to claim 1, wherein