JPH045246Y2 - - Google Patents

Description

[Detailed explanation of the idea] (Industrial application field) The present invention relates to improvements in honing tools.

(Prior art and its problems) Conventionally, as a honing tool, a grindstone fitted into a radial grindstone fitting hole formed on the outer periphery of a cylindrical tool body is inserted into a center hole in the tool body in the front-rear direction. A device in which the diameter is expanded or contracted using a slidable cone member has been proposed (see Japanese Utility Model Publication No. 178564/1983).

By the way, in the above-mentioned honing tool, if there is more clearance in the front and back direction between the grinding wheel fitting hole and the grinding wheel, when the tool retreats, the grinding wheel contacts the workpiece and retreats, causing the brake to be applied. As a result, the cone member is moved toward the front end by the amount of play, creating a gap with the cone member and reducing the diameter, resulting in a problem in that the machining accuracy of the workpiece is reduced.

(Purpose of the invention) The present invention was made in order to solve the above-mentioned conventional problems, and its purpose is to prevent the grindstone from contracting in diameter when the tool is retracted.

(Structure of the invention) Therefore, in the present invention, in the honing tool as described above, an axial sliding groove that is continuous with the grinding wheel fitting hole is formed on the front end side of the grinding wheel fitting hole of the tool body. A gap adjusting member is fitted into the sliding groove so as to be slidable back and forth, and the gap adjusting member is attached to the tool body using a fixing member with a minimum gap between the rear end of the gap adjusting member and the front end of the grindstone. It is characterized by being fixed.

(Effect of the invention) According to the invention, by sliding the gap adjustment member back and forth, there is a gap between the rear end and the front end of the grindstone fitted in the grindstone fitting hole, which prevents the diameter of the grindstone from expanding or contracting. Since the gap adjustment member is fixed to the tool body using a fixing member with a minimum gap between the two, it is the gap adjustment member that tries to move the grindstone toward the front end when the tool retreats. Because it is blocked by
This eliminates the possibility of a gap forming between the cone member and the cone member resulting in a diameter reduction, and the machining accuracy of the workpiece is improved.

(Embodiments) Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

As shown in FIGS. 1 to 3, the honing tool includes a cylindrical tool body 1, and the tool body 1 has a hole extending into the center hole 1a in the radial direction and extending in the axial direction. Grinding wheel fitting holes 1b, . . . , 1b are formed in a semicircular shape at front and rear ends.

A square bar-shaped grindstone 2 is fixed to the upper surface of each grindstone fitting hole 1b, and a grindstone expansion plate 3 having semicircular front and rear ends 3e and 3f is fitted so as to be movable in the radial direction. The lower surface of the grinding wheel expansion plate 3 has cam grooves 3a, 3.
b is formed.

Narrow grooves 3c, 3d are formed in the front end 3e and rear end 3f of the upper surface of each grindstone expansion plate 3, and O-rings 4, 4 are fitted across the narrow grooves 3c, 3d on the same side. , each grindstone expansion plate 3 is biased in the diameter-reducing (inward) direction.

A cone member 5 having cone portions 5a and 5b that abuts the cam grooves 3a and 3b of each of the grindstone expansion plates 3 is fitted into the center hole 1a of the tool body 1 so as to be slidable back and forth. During the forward sliding, the cone portions 5a and 5b move each grindstone expansion plate 3 in the diameter-expanding (outside) direction through the cam grooves 3a and 3b against the biasing force of the O-rings 4 and 4. When the cone member 5 is sliding backward, each grindstone expansion plate 3 is moved in the diameter reduction (inward) direction by the biasing force of the O-rings 4, 4 via the cam grooves 3a, 3b in the cone parts 5a, 5b. It becomes like this.

On the other hand, an axial sliding groove 1c that is continuous with each grinding wheel fitting hole 1b is formed on the front end side of each grinding wheel fitting hole 1b of the tool body 1, and each sliding groove 1c has the following features:
A gap adjustment member 6 is fitted so as to be slidable back and forth.

The rear end 6a of the gap adjustment member 6 is formed into a semicircular concave shape that fits into the semicircular front end 3e of the grindstone expansion plate 3.

The gap adjustment member 6 is fixed to the tool main body 1 with a bolt 7 inserted through a bolt hole 6b in which an adjustment allowance in the longitudinal direction is formed.

The lower surface side of the front end 6c of the gap adjustment member 6 is also formed in a semicircular concave shape, and an eccentric pin 8 rotatably press-fitted into the sliding groove 1c of the tool body 1 is abutted on the front end 6c. come into contact with

If the configuration is as above, now grindstone fitting hole 1
If there is more play (clearance) t in the front and back direction between b and the grinding wheel expansion plate 3,
When the bolt 7 is loosened and the eccentric pin 8 is rotated, the gap adjustment member 6 is slid backward while being guided by the sliding groove 1c, and the rear end 6a abuts the front end 3e of the grindstone expansion plate 3.

Then, a bolt is placed between the rear end 6a of the gap adjustment member 6 and the front end 3e of the grindstone expansion plate 3 with a minimum gap t' that does not hinder the movement of the grindstone expansion plate 3 in the radial direction. 7 to fix the gap adjustment member 6 to the tool body 1.

This allows the rear end 6a of the gap adjustment member 6 to prevent the grindstone 2 from coming into contact with the workpiece and applying a brake when the tool retreats, and from moving toward the front end together with the grindstone expansion plate 3. Become.

Therefore, as in the conventional case, the cam grooves 3a and 3b of the grindstone expansion plate 3 and the cone portion 5a of the cone member 5,
5b, which prevents the grindstone 2 from contracting in diameter together with the grindstone expansion plate 3 due to the biasing force of the O-rings 4, 4.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of the honing tool according to the present invention, Fig. 2 is a plan view of the main part of Fig. 1, and Fig. 3 is a sectional view of the honing tool according to the present invention.
It is a sectional view taken along the line - in the figure. 1... Tool body, 1a... Center hole, 1b... Grindstone fitting hole, 1c... Sliding groove, 2... Grindstone, 3...
Grinding wheel extension plate, 3e...front end, 4...O ring,
5... Cone member, 6... Gap adjustment member, 6a...
...Rear end, 7... Bolt, 8... Eccentric pin, t'...
…Minimum gap.

Claims (1)

[Scope of Claim for Utility Model Registration] A grindstone fitted into a radial grindstone fitting hole formed on the outer periphery of a cylindrical tool body with a cone member that is slidable in the front and back directions through the center hole in the tool body. In a honing tool that expands and contracts in diameter, an axial sliding groove that is continuous with the grinding wheel fitting hole is formed on the front end side of the grinding wheel fitting hole of the tool body, and a gap adjustment member slides back and forth in the sliding groove. The gap adjusting member is fixed to the tool body by a fixing member, with a minimum gap being provided between the rear end of the gap adjusting member and the front end of the grindstone, which are freely fitted together. honing tool.