JPH09304049A - Apparatus for measuring roundness - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simply, accurately measure the roundness by sliding a cam mechanism to fix a plurality of overhanging parts to the inner surface of a material to be measured, and rotating the measuring units at the axial center of the fixed part as a center to measure the displacement of the inner surface of the material. SOLUTION: Positioning pins 8 are pressed in contact with the four positions of the end of a material 1 to be measured, and the cylindrical axial direction is perpendicularly decided. Then, a knob 15A is rotated to slide the tapered part 10A toward a bearing 6, an overhanging part 3A is vertically extended via a contactor 9, and fixed to the inner surface of the material 1. At this time, the tapered part 10B is interlocked by a knob 15 belonging to the knob 15A, and the overhanging part perpendicular to the part 3A is fixed to the inner surface of the material 1. A displacement measuring gage 5 is rotated in the inner surface of the material 1 by a support arm 4 mounted at a bearing 6, and the displacement is continuously measured by a roller measuring element 19 pressed in contact with the inner surface. The maximum and minimum values of the measured values are averaged to obtain a roundness.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a measuring technique for evaluating the shape of a large-diameter component, and more particularly to a technique for measuring the roundness thereof.

[0002]

2. Description of the Related Art Roundness of a large tank such as a metal tank used in GIS or the like is measured according to the procedure shown in FIG. Inner micrometer 21 configured in a rod shape
Is arranged inside the DUT 1 such as a metal tank so as to penetrate the center point of the inner diameter of the cross section and be perpendicular to the tank axis direction, and the inner diameter is measured (a in the figure). In the same procedure, each position of the inner diameter is measured while sequentially changing the measurement position of the inner diameter (b, c, d in the figure). And based on this measurement result,
The roundness was calculated by calculating ((maximum inner diameter-minimum inner diameter) / 2).

[0003]

However, in such a method, since the inner micrometer 21 is rod-shaped,
It is difficult to arrange so that "it penetrates the center point of the inner diameter of the cross section and is perpendicular to the axial direction of the tank", and a measurement error occurs unless the skill of the individual is involved. Further, since this method is a point measurement method as described above, it is difficult to identify the maximum and minimum points of the deflection, and it is not possible to provide sufficient information when the deflection is corrected later. Therefore, an object of the present invention is to provide a roundness measuring device capable of highly accurate and precise measurement by a simpler method.

[0004]

In order to achieve the above object, the present invention provides a first cam mechanism portion which slides with respect to a fixed portion in accordance with a predetermined guide, as an invention according to claim 1. A first projecting portion that slides along with the sliding of the first cam mechanism portion according to a guide that is arranged in a direction perpendicular to the sliding direction in the cam mechanism portion; and the cam mechanism portion that is arranged in parallel with the first cam mechanism portion. According to the slide of the second cam mechanism part, the second cam mechanism part slides in the same direction, and the guides arranged at right angles to both the respective slide directions of the first cam mechanism part and the first overhang part. And a second overhanging part that slides,
A first screw mechanism unit that controls sliding between the fixed unit and the first cam mechanism unit, and a second screw mechanism that controls sliding between the first cam mechanism unit and the second cam mechanism unit. Section, a positioning pin for positioning the object to be measured from the outside of the end, a measuring section that rotates about the shaft center of the fixed section to measure the displacement of the inner surface of the object to be measured, and the data read by the measuring section is calculated. A roundness measuring instrument characterized by having a display device.

In the above circularity measuring device, the center point of the inner diameter can be more easily determined and arranged so as to be perpendicular to the axial direction of the tank, and the inner diameter can be continuously measured. .

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the roundness measuring instrument according to the present invention will be described below with reference to FIGS. 1 and 2 are overall structural views showing an installation state of a roundness measuring device on a DUT 1 which is a cylindrical body, and in particular, FIG. 1 shows an installation state viewed from the axial direction of the cylinder.
[Fig. 6] is a view showing an installed state as viewed from the side of the cylinder.

Four projecting rods formed in the same plane at right angles to each other and of the same length (in particular, two projecting rods on the same axis are designated as the first projecting portion 3A, and two projecting rods perpendicular to these are second A roundness measuring instrument having an overhang portion 3B) is GI
It is installed near the end of the cylinder such as the S metal tank. afterwards,
The projecting rods 3A and 3B are projected from the inside centering on the measuring device main body 2 and fixed to the DUT 1.

However, at this stage, the center point of the cylinder is determined,
The roundness measuring device itself is fixed to the DUT 1, but it is necessary to align the measuring device vertically with respect to the cylinder axial direction (axial center 20). Therefore, this series of work is performed by the overhanging rod 3.
It is necessary to determine the cylinder axis direction vertically with a positioning pin 8 provided at the tips of A and 3B and for positioning the cylinder end face portion from the outside.

In this way, after positioning and fixing the shaft center 20 which is the center point of the cylinder so as to "pass through the center point of the inner diameter of the cross section and be perpendicular to the axial direction of the tank", the bearing 6 provided on the shaft center 20 is mounted. By rotating the support arm 4 as the center, the displacement measuring gauge 5 provided at the tip of the support arm 4 and in contact with the inner diameter of the DUT 1 measures the displacement of the inner diameter.

The detailed structure of the roundness measuring instrument will be described below with reference to FIGS. 3 and 4. Here, FIG. 3 is an enlarged view of a sectional structure as seen from the side of the cylinder, and FIG. 4 is a diagram showing a taper portion as seen from the direction of the axis 20.

The knob 15A is connected to the measuring device main body 2,
The knob 15A is brought into contact with the screw 14A, and the knob 15A is rotated to slide along the shaft center 20 in the bearing 6 direction (right direction in the drawing). That is, it has a role as a first screw mechanism portion with respect to the measuring device main body 2 which is a fixing portion. As the knob 15A slides, the slide guide 12B
Accordingly, the taper 10A is pushed out in the same direction. The taper 10A, which is the first cam mechanism portion, slides in the bearing 6 direction (right direction in the drawing), so that the first projecting portion 3A moves in the direction of the measured object (vertical direction in the drawing) via the contactor 9. When driven, the DUT 1 is projected and fixed. The taper 10
A rotation stop pin 13 is provided to prevent the rotation of A, and a sliding guide 12A is also provided in the direction of the object to be measured (vertical direction in the drawing) to control the direction of the first protruding portion 3A.

Next, with respect to the knob 15B, the screw 1 which is interposed between the knob 15A and the knob 15A is rotated by rotating the knob 15B.
Slide through 4B. That is, it has a role as a second screw mechanism portion with respect to the knob 15A which is a movable portion. With the sliding of the knob 15B, the taper 10B, which is the second cam mechanism portion, is pushed out in the same direction, so that the second overhang portion 3B (not shown) through the contactor 9 (not shown) causes the object to be measured. Driven in the direction (front and back direction in the figure),
Overhang and fix to DUT 1.

Next, the measuring procedure by the roundness measuring device will be described together with its operation. First, as shown in FIG. 5, the positioning pin 8 is pressed against each of four end portions of the DUT 1 to vertically determine the cylindrical axis direction. In this state, the center point has not been determined yet and is in a wobbled state. Next, by rotating the knob 15A and sliding the taper 10A in the direction of the bearing 6 (rightward in FIG. 3), the first projecting portion 3A is projected in the vertical direction in FIG. After fixing to the inner surface, the overhang by the knob 15A is completed. At this time, since the knob 15B is dependent on the knob 15A via the screw 14B, the taper 10B also interlocks with the driving of the taper 10A. Therefore, there is concern that the center point of the cylinder cannot be properly positioned. However, if the second projecting portion 3B still has play after the protrusion by the knob 15A is finished, the protrusions in the four directions can be made uniform by driving the knob 15B again. On the contrary, when the protrusion of the knob 15B is completed before the protrusion of the knob 15A is completed, the protrusions in the four directions can be made uniform by rotating the knob 15B in the reverse direction, and the cylinder center point can be positioned. You can easily.

Next, by rotating the support arm 4 attached to the bearing 6 on the shaft center 20, the displacement measuring gauge 5 provided on the support arm 4 also rotates the inner surface of the cylinder and pushes it against the inner surface of the cylinder with a spring force. The displacement read by the roller probe 19 in contact is continuously measured. This data is transmitted to a calculation device (not shown), and the roundness is obtained by performing the calculation of ((maximum value-minimum value) / 2) and then displayed. Further, in the display, not only the roundness can be displayed but also the maximum and minimum portions of the deflection can be displayed, which can provide information useful in the later deflection correction. .

Further, according to the present invention, by making the projecting rod 3 detachable, it is possible to measure objects to be measured having different diameters. Needless to say, the present invention is applicable not only to roundness measurement of large-diameter parts, but also to roundness measurement of small-diameter parts.

[0016]

As described above, the roundness measuring instrument of the present invention enables highly accurate and precise measurement with a simpler method, so that stable measurement can be performed regardless of the skill level of an individual. In addition to being possible, it is possible to specify the maximum and minimum positions of the deflection, so that it is possible to provide information necessary for correcting the shape of the measured object.

[Brief description of drawings]

FIG. 1 is an overall structural view of an installation state of a roundness measuring device on a cylindrical body as seen from a cylinder axial direction.

FIG. 2 is an overall structural view of a circularity measuring device installed on a cylindrical body as viewed from the side of the cylinder.

FIG. 3 is an enlarged view of a cross-sectional structure of the roundness measuring device as viewed from the side of the cylinder.

FIG. 4 is a structural view of the taper portion of the roundness measuring device as viewed from the axial direction.

FIG. 5 is a view showing a state in which a positioning pin is pressed against the end of the object to be measured in order to determine the cylinder axis direction vertically.

FIG. 6 is a view showing a measurement state using an inside micrometer, which is a conventional method.

[Explanation of symbols]

2 ... Measuring device main body, 3A ... First overhanging portion, 3B ... Second overhanging portion, 5 ... Displacement measuring gauge, 8 ... Positioning pin, 1
0A, 10B ... Taper, 12A, 12B ... Sliding guide, 14A, 14B ... Screw, 15A, 15B ... Knob.

Claims (1)

[Claims] 1. A first cam mechanism part that slides with respect to a fixed part in accordance with a predetermined guide, and a guide arranged in a direction perpendicular to the sliding direction of the cam mechanism part according to the sliding of the first cam mechanism part. A first protruding portion that slides, a second cam mechanism portion that is arranged in parallel with the first cam mechanism portion and that slides in the same direction as the cam mechanism portion, and each of the first cam mechanism portion and the first protrusion portion. Control the slide between the fixed portion and the first cam mechanism section, and the second overhanging section that slides with the slide of the second cam mechanism section according to the guides that are arranged at right angles to both the sliding directions of And a second screw mechanism that controls sliding between the first cam mechanism and the second cam mechanism, and a positioning pin that positions the object to be measured from the outside of the end. , A circularity characterized by having a measuring unit that rotates about the axis of the fixed unit to measure the displacement of the inner surface of the object to be measured, and a device that calculates and displays the data read by the measuring unit. Measuring instrument.