JPH07280501A - Limit gage for orthogonal hole pitch - Google Patents

Abstract

PURPOSE:To exactly perform inspection of an orthogonal two-hole pitch by a limit gage even in the case where the tolerance of either hole is large. CONSTITUTION:A positioning pin 2 having a taper guide part 2a projected from a bottom face is slidably provided in a cylindrical gage body 1 whose bottom face is made a measurement guide face 1a, a slit is formed paralel to the center axis of its positioning pin 2, and a bar gage 3 is slidably set thereon. A cover 5 is mounted over the upper face of the positioning pin 2 holding a spring 4, thereon, and the upper part of the bar gage is projected from the cover. A test bar is inserted in either hole of an object to be measured, and the gage body is pressed on the end part of the other hole from upward. The taper guide part 2a is pushed through the spring 4, and the measurement guide face of the gage body comes into contact with the upper end face of the hole paralel to the center axis of the hole. If a passage face is passed and the bar gage stops on a stop face, the pitch of the object to be measured is judged within a tolerance, if the bar gage stops on the passage face, the pitch thereof is discriminated smaller than the minimum allowable size, and if it does not stop thereon, the pitch thereof is judged over the maximum allowable size.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a limit gauge for inspecting whether or not the center distance (pitch) of two orthogonal holes provided in a metal working part or the like is within a predetermined tolerance.

[0002]

2. Description of the Related Art Plug gauges are conventionally used to efficiently inspect whether the diameter of a machined hole is within a predetermined tolerance range. In Japanese Utility Model Publication No. 57-63202,
A plug gauge for hole inspection is described in which an end face on one side of the grip is provided with a stop having a maximum allowable diameter and a through hole having a minimum allowable diameter by forming a step.

FIG. 3 shows a front axle of an automobile having two orthogonal holes at both ends thereof. FIG. 3C shows the entire front axle, FIG. 3A shows an enlarged plan view of one end portion having two orthogonal holes, and FIG. 3B shows a side surface thereof. In order to inspect whether or not the center distance (hereinafter referred to as the pitch) X between the king pin hole 7 and the key bolt hole 8 of the front axle is within the allowable error range, as shown in FIG.
The test bar 6 is inserted into one hole 8 and the plug gauge 9 is inserted into the other hole 7, so that the distance A between the inner surface of the test bar 6 and the wall surface of the hole 7 facing the test bar 6 is inspected by the plug gauge 9. I have to.

[0004]

In the inspection using the above-mentioned plug gauge, in order to manage the actual pitch X of the two holes 7 and 8 which are orthogonal to each other, the dimensional tolerance of the respective hole diameters of the two holes 7 and 8,
It is necessary to determine the control dimension A of the plug gauge 9 in consideration of the outer diameter dimension tolerance of the test bar 6. Therefore, the dimensional tolerance of the diameter of each of the two holes must be controlled more strictly than the dimensional tolerance of the pitch X. If the dimensional tolerances of the hole diameters of the two holes are large, the actual pitch X cannot be controlled by the above inspection method. An object of the present invention is to provide a limit gauge capable of performing an accurate inspection even when the dimensional tolerance of one hole is large in the inspection of the pitch of two holes that intersect at right angles.

[0005]

According to the present invention, a positioning pin having a tapered guide portion projecting from the bottom surface is slidably provided in a cylindrical gauge main body having a bottom surface as a measurement guide surface. A slit is formed in the radial direction along the axial direction of the rod, a rod-shaped gauge is slidably installed in the slit, and a passage surface and a stop surface are formed as flat surfaces on the outer surface of the gauge end side, respectively, This is a limit gauge for orthogonal hole pitch in which a lid provided with a through hole for a rod-shaped gauge is attached to the upper surface of the positioning pin with a spring interposed therebetween, and the upper portion of the rod-shaped gauge is projected from the lid.

[0006]

In the measurement, the test bar is inserted into one hole of the part to be measured, the taper guide portion holding the rod-shaped gauge is inserted into the end of the other hole, and the gauge body is pressed from above. The taper guide portion is pushed through the spring, and the measurement guide surface at the bottom of the gauge body contacts the upper end surface of the hole while picking up the axial center of the hole. When the rod-shaped gauge is pushed down, the passing surface formed at the tip end of the rod-shaped gauge comes into contact with the inner ridge of the test bar, and the test bar is pressed to the outside of the inserted hole. Since the passing surface is formed as a flat surface, the flat surface of the passing surface and the ridge line of the test bar should be parallel even if the position around the axis of the rod-shaped gauge supported by the positioning pin is slightly displaced from the ridge line of the test bar. It is rotated to, which prevents the occurrence of measurement errors. If the bar gauge stops at the stop surface as it passes through the passing surface as the bar gauge is pushed down, the pitch dimension of this DUT is within the tolerance. If it does not stop, it is judged to be the maximum allowable size or more.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is an explanatory view of an embodiment of the present invention.
Is a top view, FIG. 1B is a front view, FIG. 1C is a bottom view, and FIG. 1D is a cross-sectional view taken along line XX of FIG. 1A. A positioning pin 2 is provided slidably in a cylindrical gauge body 1, and a conical taper guide portion 2a to be inserted into one of the holes to be measured is provided on the tip end side of the positioning pin 2 so as to protrude from the gauge body 1. A slit is formed in the positioning pin 2 along the axial direction and in the radial direction, and a rod-shaped gauge 3 having a rectangular cross section is slidably installed in this slit.

The bottom surface 1a of the gauge body 1 is used as a measurement guide surface, and the inside thereof is projected to serve as a support surface for the positioning pin 2, and a spring 4 is provided on the upper surface of the positioning pin 2 so that the bar gauge 3 A lid 5 having a through hole is attached.
On the outer surface of the rod-shaped gauge 3 on the tip side, a passage surface 3a and a stop surface 3b are formed by providing a step with the passage surface 3a, and the gauge body 1
1 is provided with a step portion 3c that is locked by an inner protrusion of the bottom portion of the above, and the state shown in FIG. 1 is obtained when these are assembled. Further, the passage surface 3a and the stop surface 3b of the bar-shaped gauge 3 are formed to be flat surfaces.

In the measurement, as shown in FIG. 2, the test bar 6 is inserted into one hole 8 of the component to be measured, and the conical shape of the positioning pin 2 holding the bar gauge 3 at the end of the other hole 7. Insert the taper guide part 2a of
Is pressed from above. The conical taper guide portion 2a is pushed through the spring 4, and the bottom surface 1a of the gauge body 1 contacts the upper end surface of the hole 7 while picking up the axial center of the hole 7. Therefore, the bottom surface 1a of the gauge main body 1 is in close contact with the upper end surface of the hole 7, and in this state, the gauge main body 1 does not tilt with respect to the measurement hole 7, and its axis matches the axis of the hole 7.

When the bar gauge 3 is pushed down, the passing surface 3a first comes into contact with the inner ridge of the test bar 6, and the test bar 6
To the outside of the hole 8 in which it is inserted. Since the passing surface 3a is formed as a flat surface, the position around the axis of the rod-shaped gauge 3 supported by the positioning pin 2 is set at the test bar 6a.
Even if it is slightly deviated from the ridge line direction, the plane of the passing surface 3a and the ridge line of the test bar 6 are rotated so as to be parallel to each other, thereby preventing a measurement error from occurring. If the rod-shaped gauge 3 passes through the passing surface 3a and stops at the stop surface 3b as the rod-shaped gauge 3 is pushed down, the pitch dimension of the measured object is within the tolerance. If the pushing down of the rod-shaped gauge 3 stops on the passing surface 3a, it is below the minimum allowable dimension, and if it does not stop on the stop surface 3b, it is determined to be above the maximum allowable dimension.

In the above embodiment, the taper guide portion 2a formed on the positioning pin 2 has a conical shape, but the shape is not limited to the conical shape, and when it is inserted into the end face of the hole to be measured, the center of the hole is picked up for positioning. Any shape may be used as long as it has a tapered guide portion. Further, although the rod-shaped gauge 3 is shown as having a rectangular cross section, it may be any one that can slide in the slit of the positioning pin and does not rotate.

[0012]

According to the present invention, in the measurement of the pitch of two orthogonal holes, even if the tolerance of one hole is large, it is possible to use a limit gauge for inspection, and this limit gauge is used for the inspection. Since the inclination of the gauge and the position around the axis are regulated, it is possible to perform an accurate inspection without causing a measurement error due to an inadequate inspection.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of an embodiment of the present invention.

FIG. 2 is an explanatory diagram of a two-hole pitch inspection according to an embodiment.

FIG. 3 is an explanatory view of a part to be measured.

FIG. 4 is an explanatory view of a conventional two-hole pitch inspection.

[Explanation of symbols]

1 Gauge body 2 Positioning pin 3 Bar gauge 4 Spring 5 Lid 6 Test bar

Claims (1)

[Claims] 1. A positioning pin having a tapered guide portion projecting from the bottom surface is slidably provided in a cylindrical gauge main body having a bottom surface as a measurement guide surface, and the positioning pin is provided along the axial direction of the positioning pin. Forming a slit in the radial direction,
A rod-shaped gauge is slidably installed in the slit, a passing surface and a stop surface are formed as flat surfaces on the outer surface of the tip end side of the gauge, and a spring is interposed on the upper surface of the positioning pin to insert the rod-shaped gauge. A limit gauge for orthogonal hole pitch, wherein a lid provided with holes is attached, and an upper portion of the rod-shaped gauge is projected from the lid.