JPH0642162Y2 - Roundness measuring instrument - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a roundness measuring instrument for measuring the roundness of the inner diameter of a measured object having an inner peripheral surface such as a pipe.

[Prior Art] Conventionally, as a roundness measuring device for measuring the roundness of the inner diameter of a tube, there is one described in, for example, JP-A-57-119208.

In this device, a turning roller for supporting the lower part of the outer peripheral surface of the object to be measured and rotating the same is provided on the platform, and the turning roller is driven by a motor.
Inside the inner peripheral surface of the object to be measured, there is inserted a main body having a distance detector and a displacement amount detector on the legs or the like with wheels abutting against the inner peripheral surface. It is supported by a horizontal pin located on the axis. Further, both ends of this pin are supported by a pair of stands located outside both open ends of the object to be measured, and the stands are fixed on the base.

Then, by rotating the turning roller that supports the lower portion of the outer peripheral surface of the measured object with a motor, the measured object is rotated, and the wheel connected to the distance detector and the displacement amount detector rotates. The inner diameter of the object to be measured is measured by following the runout of the inner peripheral surface.

[Problems to be solved by the invention] However, in such a device, each member is dispersed inside and outside the object to be measured, the structure is complicated and large, and the object to be measured is rotated to reduce the inner diameter. When the object to be measured is a long object for measurement, there is a drawback that the measuring device becomes large and it is difficult to measure the entire length of the object to be measured or at an arbitrary position, resulting in an increase in manufacturing cost. Moreover, if the object to be measured is a long one and the straightness is poor, it is difficult to measure the roundness accurately. In addition, if the object to be measured is a heavy object, the size of the drive motor for rotating the object increases.

In view of these problems, the present invention has an object to provide a roundness measuring instrument having a relatively simple structure and capable of easily measuring the roundness of the diameter of the inner peripheral surface of the measured object. And

[Construction of the Invention] The roundness measuring instrument according to the present invention can be inserted into the inner peripheral surface of the object to be measured. A cylindrical member having a relatively small diameter that is rotatable with respect to the object to be measured, and is arranged on the outer peripheral surface of this cylindrical member so as to be spaced apart in the circumferential direction so that the respective axial directions are parallel to the axial line of this cylindrical member And the two rollers that are supported by the cylindrical member and project from the outer peripheral surface, and are urged outward in the radial direction of the cylindrical member by a spring so that the tip roller can be pressed against the inner peripheral surface of the measured object. Is provided at the other end of the pressing member and the other end of the pressing member protruding into the inner peripheral surface of the cylindrical member, and the tip roller of this pressing member is measured against the biasing force of the spring. It consists of an operating part that is separated from the inner peripheral surface of the body, and a dial gauge that is attached to the cylindrical member and that has a probe protruding from the outer peripheral surface of the cylindrical member and capable of advancing and retracting in the radial direction of the cylindrical member. Is characterized by.

[Embodiment] An embodiment of the present invention will be described below with reference to FIGS. 1 to 3. FIG. 1 is a front view of a measuring state showing a part of the present invention as a fracture surface, and FIG. 2 is a partial arrow view of the roundness measuring instrument of FIG. FIG. 3 is a partially cutaway side view showing a roundness measuring state of the object to be measured by the roundness measuring instrument.

FIG. 1 shows a state in which a roundness measuring device is arranged on, for example, a cylindrical object 3 to be measured. A stepped hole 12 is provided at a predetermined position of a cylinder 11 forming the main body of this roundness measuring instrument.
Are formed in the radial direction of the cylinder 11. A dial gauge 14 having a lever (measuring element moving device) 13 is partially inserted and attached to the hole 12. The probe 15 of the dial gauge 14 projects from the outer peripheral surface 11a of the cylinder 11, and can be moved in the radial direction of the cylinder 11 via the spindle 17 by operating the lever 13 located in the inner peripheral surface 11b. Has been done.

In addition, as shown in FIG.
Two rollers 18 are attached at positions symmetrical to each other with respect to the central axis of 17 and spaced apart from each other. These rollers 18 have their axial direction aligned with the axial direction of the cylinder 11, are separated from each other in the circumferential direction of the cylinder 11, and have a part of their outer peripheral surfaces projecting from the outer peripheral surface 11a of the cylinder 11 to form the cylinder 11. It is rotatably and fixedly mounted on the cylinder 11 via a fixed shaft 19. The shaft 19 is a cylinder 11 as shown in FIG.
The roller 18 is fixed by being tightened by a nut 20 and is fitted in a recess 21 formed in the cylinder 11.

In addition, two sets of pressing members 22 are attached to both sides of the dial gauge 14 in the circumferential direction of the cylinder 11 so as to be displaced from the rollers 18 in the circumferential direction. That is, in the cylinder 11, two stepped holes 23 are formed at positions symmetrical to each other with respect to the central axis of the spindle 17 of the dial gauge 14. A rod 24 is inserted into the hole 23 so as to be movable in the radial direction of the cylinder 11, and a roller 25 is rotatably attached to one end of the rod 24. The roller 24 has a collar 26 at its intermediate portion, and a spring 28 is provided between the collar 26 and a lid 27 which is inserted through the rod 24 and screwed into the hole 23.
Is provided. This spring 28 keeps the roller 25 always in the cylinder 11
In the radial direction and is urged to the outer side (the inner peripheral surface side of the measured object). These rollers 25, rod 24, lid 27, spring 28
The pressing member 22 is constituted by.

Further, a bell crank 29a or a bell crank 29b is rotatably attached to the other end of the rod 24 by fitting a long hole 30 thereof into a pin 31. This bell crank 29a, 29b
Is rotatably attached to a bracket 32 fixed to the inner peripheral surface 11b of the cylinder 11. Bell crank 29a or bell crank 29b, bracket 32, pin 31, etc.
3 are configured.

Next, the operation of the roundness measuring instrument configured as described above will be described.

(1) The cylindrical object 3 to be measured is held substantially horizontally on a table or the like as shown in FIG.

(2) Both bell cranks 29a, 29b are respectively rotated in the directions of arrow A and arrow B in FIG. 1, and the roller 25 is moved to the cylinder 11 side against the force of the spring 28 via the pin 31 and the rod 24. Then, the lever 13 is rotated in the direction of arrow C in FIG. 1 to move the probe 15 to the cylinder 11 side via the spindle 17.

(3) In this state, the cylinder 11 is fitted to the object 3 to be measured (the cylinder 11 is positioned inside the object 3 to be measured) and a predetermined position in the axial direction of the object 3 to be measured (roundness should be measured). Location).

(4) The bell cranks 29a, 29b and the lever 13 are free. Then, the roller 25 presses the inner peripheral surface 3a of the measured body 3 by the force of the spring 28, and the roller 18 of the cylinder 11 is pressed against the inner peripheral surface 3a of the measured body 3 by its reaction, so that the two rollers 18 and Two
The cylinder 11 is held by the inner surface 3a of the body 3 to be measured by the two rollers 25, and in this state, the probe 15 contacts the inner surface 3a of the body 3 to be measured.

(5) After confirming that the tracing stylus 15 is in contact with the inner peripheral surface 3a of the object 3 to be measured, align the 0 mark on the dial plate of the dial gauge 14 with the pointer.

(6) With the two rollers 18 and the two rollers 25 in contact with the object 3 to be measured, the cylinder 11 is rotated with respect to the object 3 to be measured, and the graduation display of the dial gauge 14 is sequentially read.

(7) Repeating the above (2) to (6), the roundness of a predetermined portion of the DUT 3 is measured.

(8) After the measurement, bell cranks 29a, 29b, lever 13
Respectively in the direction of arrow A, B, C in FIG. 1,
The cylinder 11 is moved in the axial direction thereof and removed from the device under test 3.

[Effects of the Invention] As described above, according to the present invention, the cylindrical member inserted into the inner peripheral surface of the object to be measured, the two rollers arranged on the outer peripheral surface of the cylindrical member, and the cylindrical member are provided. A pressing member that is supported and protrudes from the outer peripheral surface and is urged radially outward of the cylindrical member by a spring so that the tip roller can be pressed against the inner peripheral surface of the object to be measured, and a probe attached to the cylindrical member. Is equipped with a dial gauge capable of advancing and retracting in the radial direction of the cylindrical member, so that the inner diameter of the measured object can be measured with the entire measuring instrument positioned on the inner peripheral surface of the measured object. .

Therefore, the circularity of the inner diameter of the measured object can be easily and surely measured at any place by rotating the cylindrical member without rotating the measured object. Therefore, it can be applied to the roundness measurement of a heavy object or a long object, and even if the straightness is poor, it can be measured at any position over the entire length. Moreover,
It has the advantages that its configuration is relatively simple, the device is small, and its manufacturing cost is low.

[Brief description of drawings]

FIG. 1 shows a roundness measuring instrument according to an embodiment of the present invention.
A front view showing a part as a broken surface, FIG. 2 is a partial arrow view of the roundness measuring instrument of FIG. 1 seen from the direction III, and FIG. 3 is a perfect circle of the object to be measured by the roundness measuring instrument. It is a partially broken side view showing a degree measurement state. 3 ... Object to be measured, 11 ... Cylindrical, 13 ... Lever (moving device of measuring element), 14 ... Dial gauge, 15 ... Measuring element, 18,2
5 …… Roller, 22 …… Pressing member, 24 …… Rod, 26 ……
Tsuba, 28 …… Spring, 29a, 29b …… Bell crank, 33 …… Operating section

Claims (1)

[Scope of utility model registration request] 1. A cylindrical member having a relatively small diameter, which can be inserted into an inner peripheral surface of a measured object and is rotatable with respect to the measured object, and a cylinder having an axial direction on the outer peripheral surface of the cylindrical member. Two rollers that are arranged so as to be spaced apart in the circumferential direction so as to be parallel to the axis of the member, and are supported by the cylindrical member and project from the outer peripheral surface, and are urged by a spring to the outside in the radial direction of the cylindrical member. The distal end roller can be pressed against the inner peripheral surface of the object to be measured, and the pressing member is arranged at a distance in the circumferential direction, and the other end of the pressing member protruding into the inner peripheral surface of the cylindrical member. An operating section which is provided to separate the tip roller of the pressing member from the inner peripheral surface of the object to be measured against the biasing force of a spring; A diamond that protrudes from the outer peripheral surface of the member and can move back and forth in the radial direction of the cylindrical member Roundness measuring instrument consisting of a gauge and.