JP2569890Y2 - Straightness measuring tool - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a straightness measuring tool suitable for measuring straightness of a quill hole or the like of a headstock of a machine tool with high accuracy.

[0002]

2. Description of the Related Art A precision machined hole such as a quill hole in a headstock that requires a high degree of straightness requires a high degree of straightness measurement. Therefore, various types of straightness measuring means are employed. Conventionally, generally used one is to put a mirror body in a measurement hole such as a quill hole, move the mirror body along the inner wall of the measurement hole, and measure the deflection or the like of the mirror body with an autocollimator. .

[0003]

The main structure of the straightness measuring means is that the mirror must be closely engaged with the measuring hole and move straight along the axial direction of the measuring hole. In addition, it is necessary that the mirror surface surely fluctuates in proportion to the undulation of the inner wall. However, there are few conventional ones generally satisfying the above-mentioned main structure, requiring a high-level measurement technique. There is also a problem that the structure of the measuring means is complicated and difficult to handle.

The present invention solves the above-mentioned problems, and provides a straightness measuring instrument which can measure straightness of a measurement hole easily and with high accuracy and is formed in a simple structure which is easy to handle. The purpose is to:

[0005]

In order to achieve the above object, the present invention provides a guide bar which is removably inserted into a measurement hole of an object to be measured and has a groove formed along the insertion direction. A measuring piece with a mirror, which is slidably inserted into a space between the concave groove of the guide bar inserted into the measuring hole and the inner wall of the measuring hole and has a mirror formed on a side end face, and the measuring piece. The straightness measuring tool comprises a pressing means for pressing against the inner wall of the measurement hole and an autocollimator disposed at a position facing the mirror.

[0006]

[Action] A guide bar is inserted into the measurement hole. Since a groove is formed in the guide bar along the axial direction, the measurement piece with the mirror is slidably inserted into the space between the groove and the inner wall of the measurement hole, so that the measurement piece with the mirror is measured. Move correctly along the axis of the hole. In addition, the measuring piece with the mirror is pressed against the inner wall of the measuring hole by the pressing means, and the mirror is formed directly on the side end surface, so that the undulation of the measuring hole is directly reflected on the movement of the mirror. By measuring the movement of the mirror with an autocollimator, highly accurate straightness can be measured.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a measuring piece 1 with a mirror used in this embodiment.
It is a perspective view which shows the whole structure of. The bridge body 6 is formed of an elongated saddle-shaped member forming an arc-shaped contact portion 5 on the top side. Both ends are formed flat, and a mirror 7 is formed at one end. At the other end where the mirror 7 is not formed, a lock 8
The wire 9 is connected via. A groove 10 is formed on the opposite side of the piece main body 6 from the contact portion 5. FIG. 2 is a sectional view of the measuring piece 1 with a mirror shown in FIG. 1 and shows a state where a leaf spring 3 as a pressing means is attached. The leaf spring 3 is formed in a wave shape, is housed in the groove 10 of the bridge body 6, and is fixed by screws 11. In addition, the leaf spring 3 is attached in a state where the wave-shaped peak portion 12 slightly protrudes from the inside of the groove 10.

FIG. 3 is a perspective view showing the entire structure of the guide bar 3. The guide bar 2 is formed of a slender cylindrical body, and its outer diameter is formed so as to be slidable in a measurement hole of an object to be measured (not shown). As shown in FIG. 4, a concave groove 13 is formed on the outer peripheral side so as to penetrate in the axial direction. Further, a plurality of (seven in the figure) through holes 14 for weight reduction are formed. In addition,
The concave groove 13 has an area capable of accommodating the measuring piece 1 with a mirror. More specifically, the concave groove 13 has a width dimension for slidably supporting the side surface of the measuring piece 1 with a mirror, and has a measurement with a mirror. The contact portion 5 of the piece 1 is formed of a groove having a depth of the groove slightly protruding from the inside of the groove 13. Also,
The ridge 12 of the leaf spring 3 fixed to the mirrored measuring piece 1 is in contact with the bottom surface 15 of the concave groove 13.

FIG. 5 shows that the measuring piece 1 with a mirror and the guide bar 2 of this embodiment are inserted into the quill hole 17 in order to measure the straightness of the quill hole 17 of the headstock 16 which is one of the objects to be measured. It is a front view showing the state where it did. The guide bar 2 is inserted into the quill hole 17 and the groove 13 of the guide bar 2 is inserted.
A measuring piece 1 with a mirror is slidably inserted therein. As described above, the ridge 12 of the leaf spring 3 comes into contact with the bottom surface 15 of the concave groove 13, so that the contact portion 5 of the mirrored measuring piece 1 is pressed against the inner wall 18 of the quill hole 17. As shown in FIG. 5, the measuring piece with mirror 1 is arranged with the mirror 7 facing the front.

FIG. 6 is a side view for explaining the straightness measuring method. An autocollimator 4 which is one of the straightness measuring tools is mounted at a predetermined position. The headstock 16 is the base 1
9 mounted. The mirror 7 of the measuring piece 1 with a mirror is arranged at a position facing the autocollimator 4. The wire 9 connected to the mirror-equipped measurement piece 1 extends in the horizontal direction, and is wound or unwound by the winding device 20. As a result, the measuring piece with mirror 1 reciprocates in the quill hole 17. By driving the winding device 20 with the above structure, the measuring piece with mirror 1 is guided by the concave groove 13 of the guide bar 2 and moves along the axial direction of the quill hole 17. The contact portion 5 of the measuring piece 1 with the mirror is the inner wall 18 of the quill hole 17.
The quill hole 1 is always pressed by the leaf spring 3.
7, the contact portion 5 moves. Thereby, the mirror 7 moves and changes the inclination angle. The change in the inclination angle of the mirror 7 is incident on the autocollimator 4 side, and the undulation of the quill hole 17, that is, the straightness is measured.

In the above embodiment, the measuring piece with mirror 1 and the guide bar 2 have the shapes as shown in the figure, but the detailed structure is not limited to that shown. In addition, the mirror 7 may be attached separately.
The leaf spring 3 is not limited to the illustrated shape. Further, fixing means for fixing the guide bar 2 inserted into the quill hole 17 to the headstock 16 may be provided, and the guide bar 2 may be fixed at a predetermined position.

[0012]

According to the present invention, the following effects can be obtained. (1) Since the measuring piece with the mirror moves accurately along the axial direction of the measuring hole along the groove of the guide bar, and the contact portion is constantly pressed against the inner wall of the measuring hole by the pressing means, high accuracy is achieved. Can be measured. (2) By moving the mirror-equipped measurement piece along the concave groove, the mirror integrally disposed on the mirror-equipped measurement piece moves, and the movement is incident on the autocollimator. Easy and quick. Therefore, high-precision straightness measurement can be performed without requiring special skill. (3) The guide bar is inserted into the measurement hole, and handling is easy.

[Brief description of the drawings]

FIG. 1 is a perspective view showing the entire structure of a measuring piece with a mirror according to one embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a state in which pressing means is attached to the cross-sectional view taken along line AA of FIG.

FIG. 3 is a perspective view showing the entire structure of the guide bar of the present embodiment.

FIG. 4 is an enlarged sectional view taken along line BB of FIG. 3;

FIG. 5 is a front view showing a state in which a measurement piece with a mirror, a guide bar, and the like according to the present embodiment are inserted into an object to be measured.

FIG. 6 is a side view showing a measuring method according to the present embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Measuring piece with mirror 2 Guide bar 3 Leaf spring 4 Autocollimator 5 Contact part 6 Piece body 7 Mirror 8 Locking tool 9 Wire 10 Groove 11 Screw 12 Mountain part 13 Concave groove 14 Through hole 15 Bottom surface 16 Headstock 17 Quill hole 18 Inner wall 19 Base stand 20 Winding device

Claims (1)

(57) [Scope of request for utility model registration] 1. A guide bar removably inserted into a measurement hole of an object to be measured and having a concave groove formed along the insertion direction, and a groove formed between the guide bar and the measurement hole inserted into the measurement hole. A measuring piece with a mirror, which is slidably inserted into the space between the inner walls and has a mirror formed on a side end face, pressing means for pressing the measuring piece against the inner wall of the measuring hole, A straightness measuring instrument comprising an autocollimator arranged at a position facing the straightness.