JPH065080Y2 - Tool mounting jig - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a tool mounting jig for a grinding device, a milling device, or the like, in which a machining tool is mounted and rotationally driven.

[Conventional technology]

For processing such as grinding and cutting, usually, after attaching and fixing a disk-shaped grinding wheel or milling cutter whose outer peripheral surface is formed on the processing blade surface to a tool mounting jig such as a grinding device or a milling device, This is rotatably driven and pressed against the machined surface of the workpiece. Examples of the tool attachment jig include those shown in FIG.
This tool mounting jig has a large diameter portion 1 composed of a rotary drive shaft,
The large diameter portion 1 extends downward from the center of the lower end surface 2,
On the outer periphery thereof, there is a shaft portion 3 to which a mounting tool 5 (dashed line) is mounted. The shaft portion 3 has an axial length longer than the thickness of the tool 5, and the lower portion is formed into a screw shaft 4 having a smaller diameter than the shaft diameter of the upper portion. To attach the processing tool 5 to such a tool attachment jig, the mounting hole 6 of the processing tool 5 is fitted into the shaft portion 3 and the upper surface of the processing tool 5 is attached to the lower end surface 2 of the large diameter portion 1. After abutting, the flange nut 7 is attached to the screw shaft portion 4 of the shaft portion 3 protruding downward from the mounting hole 6 of the processing tool 5.
The upper surface of the flange nut 7 and the large diameter portion 1
It is performed by sandwiching the processing tool 5 with the lower end surface 2 of the. Then, by rotating the large-diameter portion 1 of the tool attachment jig to which the machining tool 5 is attached in this way, the machining tool 5 is rotationally driven together with the tool attachment jig, and the workpiece is machined. Further, as another example of the tool mounting jig, there is a type in which the shaft portion 8 is shorter than the thickness of the working tool 5 as shown in FIG. Lower end surface 8 of the shaft part of this tool mounting jig
A screw hole is formed in the center of the shaft a. By attaching the processing tool 5 to the shaft portion 8 as shown by the alternate long and short dash line, and then screwing the flanged screw 9 into the screw hole of the shaft lower end surface 8a from below. The processing tool 5 is attached and fixed. The other parts are the same as those in FIG. 6 and are given the same numbers.

[Problems to be solved by the invention]

However, in any of these tool mounting jigs, in order to facilitate the mounting of the machining tool 5, the shaft diameters of the shaft portions 3 and 8 are made slightly smaller than the inner diameter of the mounting hole 6 of the machining tool 5. Therefore, the inner peripheral surface of the mounting hole and the outer peripheral surfaces of the shaft portions 3 and 8 do not come into close contact with each other, and some voids are generated. Therefore, when the processing tool 5 is attached, the processing tool 5 is attached to the shaft portions 3, 8
It is extremely difficult to precisely and concentrically attach the same, and since it is usually attached in an eccentric state, it is difficult to form a precise machined surface. Further, the shaft portions 3, 8
In some cases, the machining tool 5 attached to the tool shifts to the left or right due to the rotation of the shaft portions 3 and 8, which becomes an obstacle to precision machining and at the same time shortens the tool life.

Therefore, for example, in Japanese Utility Model Publication No. Sho-12224293,
It has been proposed to center the machining tool 5 using an expansion ring with elastically expandable notches. However, the expansion ring not only requires precision in the outer peripheral dimension and the inner peripheral dimension, but also has to be formed with a threaded hole for attachment, a burrow hole and a notch capable of elastic expansion in its ring surface There is a problem that the manufacturing cost is high. Since the notch is forcedly expanded along the mounting axis, there is a problem that distortion and damage are likely to occur in the peripheral portion of the notch.

It is also conceivable to use a centering fixture that holds rigid spheres in an annular shape at equal intervals as described in Japanese Utility Model Laid-Open No. 53-59786. However, in this centering fixture, the structure for holding the hard sphere is a complicated structure that combines the retainer support portion, the compression coil spring, and the retainer ring, so the number of parts is large and it takes time to install. It has a problem that the price is expensive.
And above all, the centering fixture is intended for centering the workpiece to be placed on the machine tool base,
The above-mentioned components are placed in order from the bottom, and the upper cylinder covers to finally integrate them.
Processing tool 5 to be attached to the downward shaft as shown in the figure
There is a problem that it is difficult to apply it to the alignment of.

The present invention has been made in view of such circumstances, and is capable of concentrically mounting a machining tool without misalignment, forming a precise machining surface, and extending the life of the tool. The purpose is to provide.

[Means for solving problems]

In order to achieve the above object, a tool mounting jig of the present invention coaxially projects from a large-diameter portion composed of a rotary drive shaft and an end surface of a lower end of the large-diameter portion which is smaller in diameter than the large-diameter portion. A tool mounting jig having a shaft portion which is provided with a machining tool fitted therein by means of its mounting hole, and a fixing means for fixing the machining tool fitted onto the shaft portion. The diameter side portion is formed into a truncated cone taper portion having a smaller diameter on the lower side, and the other portion is formed into a screw shaft, and a plurality of spherical bodies having a uniform diameter are arranged at predetermined intervals, respectively. An expandable positioning ring formed by connecting with a rubber thread is fitted onto the outer peripheral surface of the truncated cone tapered portion in a stretched state, and the spherical body of the positioning ring is attached to the outer circumference of the truncated cone tapered portion and this. Insert the nut to push it into the space between the mounting hole of the processing tool and the screw A configuration that engaged leek.

Next, this invention will be described in detail based on embodiments.

〔Example〕

FIG. 1 shows an embodiment in which the present invention is applied to a grinding machine. The tool mounting jig in this grinding apparatus includes a large diameter portion 10 composed of a rotary drive shaft and a lower end surface 11 of the large diameter portion 10.
Is provided with a shaft portion 13 extending downward from the center of the center and having an attachment processing tool (grinding stone) 12 (one-dot chain line) attached thereto. The shaft portion 13 has an axial length longer than the thickness of the tool 12, and the portion on the large diameter portion 10 side is formed as a truncated cone taper portion 14 having a smaller diameter on the lower side and below the tapered portion. Is formed on the screw shaft 15. By forming a through hole in the center of a plurality of hard spheres 16 of the same size on the outer periphery of the taper portion 14 and sequentially passing through the rubber thread 16a, the hard spheres 16 are arranged at predetermined intervals and positioned and fixed by an adhesive or the like. A positioning ring 17 (see FIG. 2) formed as a telescopic ring is externally fitted in a state in which it is stretched to some extent. The lower end surface of the positioning ring 17 is horizontally lifted and supported by the upper surface of the nut 18 engaged with the screw shaft 15. That is, the positioning ring 17 tightens the nut 18 and the screw shaft 15
As it rises along the above, it is pushed by the upper surface of the nut 18 and rises along the outer peripheral surface of the tapered portion 14, and is sandwiched between the outer peripheral surface of the tapered portion 14 and the upper surface of the nut 18. Reference numeral 19 is a flange nut for pressing and fixing the processing tool 12 when the processing tool 12 is attached as shown by the chain line.

To mount the processing tool 12 in this tool mounting jig, first, the mounting hole 20 of the processing tool 12 is fitted into the shaft portion 13 of the tool mounting jig, and then the outer periphery of the shaft portion 13 and the mounting hole of the tool 12 are mounted. The positioning ring 17 is fitted in the gap between the two. At this time, since the positioning ring 17 is fitted to the outer peripheral surface of the shaft portion 13 in the extended state, even if the gap between the shaft portion 13 and the hole 20 is larger than the positioning ring 17 in the lower portion, Even if the nut 18 is not engaged, it can be temporarily fixed as it is. Then, next, the nut 18 is engaged with the screw shaft 15 and brought into contact with the lower surface of the positioning ring 17 from below, and the nut 18 is screwed up from this state. As a result, the positioning ring 17 moves the nut 18
It is pushed by the upper surface of and rises along the outer peripheral surface of the tapered portion 14 while maintaining a horizontal posture. As a result, in the space between the outer periphery of the shaft portion 13 and the inner periphery of the mounting hole 20 of the machining tool 12, the hard spheres 16 of the same size are located at predetermined intervals in the circumferential direction, and the outer periphery of the shaft portion 13 is mounted. The size of the void with the inner circumference of the hole 20 is made uniform in the circumferential direction. Therefore, the machining tool 12 is automatically attached to the shaft portion 13 in a precise concentric state, and the relationship is maintained even when the shaft portion 13 rotates. The processing tool 12 is pressed and fixed by the flange nut 19 while maintaining the above relationship.

As described above, in the above-described embodiment, the machining tool 12 is attached to the shaft portion 13 in a precise concentric state, and the state is maintained during machining. Therefore, it is possible to always form a processed surface with excellent accuracy. And the life of the tool used is extended.

In the tool mounting jig of the above embodiment, the shaft length of the shaft portion 13 is longer than the thickness of the mounting processing tool 12, and the flange nut 19 is attached to the screw shaft 15 protruding from the mounting hole 20 of the mounting processing tool 12. By screwing in, the upper surface of the flange nut 19 and the lower end surface 11 of the large-diameter portion 10 form the processing tool 1
Although the work tool 12 is clamped by pressing the work piece 2, the shaft portion 13 does not necessarily have to be longer than the thickness of the work tool. That is, as shown in FIG. 3, the shaft length of the shaft portion 13 'is made shorter than the thickness of the machining tool 12, and a screw hole is bored in the center of the lower end surface thereof. The working tool 12 can be fixed by fitting the threaded portion 22 into the screw hole and screwing it in. The positioning ring is omitted in the figure.

Further, the fixing method of the working tool as described above is a method of fixing the working tool having a diameter of up to about 200 mm, and the working tool having a diameter of more than that, particularly about 500 to 600 mm is large. If you use one,
As shown in FIG. 4, the machining tool 12 positioned by the positioning ring 17 (see FIG. 1) is directly attached to the large diameter portion 1
It is preferable to screw it to the lower end surface 11 of 0. Of course, the screw fixing and the fixing using the flange nut 19 or the flanged screw 22 may be combined.

Furthermore, the embodiments described so far (Fig. 1, Fig. 3,
4) is a type in which the tool 12 is directly attached by contacting the tool 12 with the lower end surface 11 of the large diameter portion 10 of the rotary drive shaft, but as shown in FIG. It can also be applied to a type in which the tool 12 is attached through the tool attachment flange 25. That is, in this type, the center of the lower end surface 11 of the rotary drive shaft is normally the flange 25.
It is formed in the mounting truncated cone taper portion 26, the taper hole portion 27 of the flange 25 is fitted into the taper portion 26,
The flange 25 is attached concentrically with the rotary drive shaft by inserting a bolt from the lower end surface of the flange 25 and engaging with a female screw 28 formed in the lower end surface of the taper portion 26. Since the flange 25 thus mounted rotates integrally with the rotary drive shaft, it can be considered that the rotary drive shaft is extended. The other parts are similar to those of the embodiment shown in FIG. 1, and the same parts are designated by the same reference numerals. The taper portion 29 in FIG. 5 corresponds to the taper portion 14 in FIG.

Further, the machining tool attached to the tool attachment jig of the present invention is not limited to the above-mentioned one, and any disc-shaped machining tool whose outer peripheral surface is a machining blade surface can be used. But it's okay.

[Effect of device]

As described above, in the tool mounting jig of the present invention, a part of the tool mounting shaft is formed in a tapered shape, and the portion between the outer periphery of the tapered portion and the inner periphery of the mounting hole of the mounting processing tool is formed. An expandable positioning ring consisting of a plurality of spherical bodies of the same size is fitted in the void in an extended state, so when mounting the machining tool, the shaft outer circumference and the machining tool mounting hole inner circumference The machining tool is positioned so that the size of the void is always uniform in the circumferential direction. Moreover, since the positioning ring is expandable and contractible, it can be easily temporarily fixed to the shaft portion that extends downward, and after that, simply by lifting it horizontally with a nut, it is easy to properly position it between the shaft portion and the processing tool. Can be clamped. Therefore, unlike the conventional case, a centering jig having a complicated structure is not required, and the machining tool can be attached to the shaft portion in a precise concentric state with a simple operation.
Moreover, since this precise concentric state is maintained even during processing in which the machining tool is rotationally driven, it is possible to form a machined surface with excellent precision on the workpiece and extend the life of the machining tool. It is what is done. In addition, this tool mounting jig can be obtained by a simple method in which a part of the conventional tool mounting jig is additionally processed and a spherical body is connected with a rubber thread to form a positioning ring. It is cheap and very practical.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an embodiment of the present invention, FIG. 2 is a perspective view of a tool positioning ring used in the above embodiment, and FIG.
FIG. 4, FIG. 4 and FIG. 5 are vertical sectional views showing still another embodiment respectively, FIG. 6 is a vertical sectional view showing a conventional tool mounting jig, and FIG. 7 is another conventional tool mounting jig. FIG. 10 ... Large diameter part, 11 ... Lower end surface, 12 ... Processing tool,
13 ... Shaft part, 14 ... Tapered part, 15 ... Screw shaft part,
16 ... Hard ball, 16a ... Rubber thread, 17 ... Positioning ring, 18 ... Nut, 19 ... Flange nut, 20
...... Mounting holes

Claims (1)

[Scope of utility model registration request] Claim: What is claimed is: 1. A large-diameter portion comprising a rotary drive shaft and a smaller diameter than the large-diameter portion. And a fixing means for fixing a machining tool externally fitted to the shaft portion, wherein the large-diameter-side portion of the shaft portion has a downward cone-shaped truncated cone. Positioning ring which is formed on the tapered part and the other part is formed on the screw shaft, and a plurality of spherical bodies of uniform diameter are arranged at predetermined intervals and connected to each other by rubber threads. Is externally fitted to the outer peripheral surface of the truncated cone tapered portion in a stretched state, and the spherical body of the positioning ring is pushed into the space between the outer circumference of the truncated cone tapered portion and the mounting hole of the processing tool to be mounted on the spherical body. Tool mounting jig characterized in that a nut for fitting is screwed onto the screw shaft