JPH03184714A - Structure of broach and grinding method thereof - Google Patents

Abstract

PURPOSE:To enable the exchange of a ring edge base and to enable a highly accurate grinding with each edge base being fitted reversely, by providing a lot of ring edge bases forming cutting edges at the outer peripheral parts and forming an edge line with each edge base being engaged in series with a core bar. CONSTITUTION:This broach is provided with a core bar 11, provided with a lot of ring edge bases 12 where cutting edges 13 are formed at the outer peripheral parts and each ring edge base 12 is engaged with the core bar 11 in series. Moreover, an edge line 10 is formed, bar like guides 15, 16 are provided at both ends of the core bar 11, one part of the guide 15 is linked detachably from the core bar 11 as well and each ring edge base 12 engaged with the core bar 11 by each guide 15, 16 are fixed with the fastening in the axial direction. Also, when each ring edge base 12 is fixed to the core bar 11 with its turning over, the flank of each cutting edge 13 becomes an escape slope. When a grinding wheel is linearly moved in the arrangement direction of each flank while rotating it in this state, these each flank become to be ground in order.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to the structure of a broach tool for forming various holes, such as spline teeth, key grooves, etc., in the inner circumference of a cylindrical workpiece, and its polishing. It is about the method.

(Conventional technology) As a conventional technique, there is a structure shown in FIG.

In Fig. 6, A is a broach tool for forming spline holes, and has a blade row part 1 in the middle part.

It integrally has guide parts 5 and 6 at both ends.

The blade array section 1 is formed by forming a large number of blade holders 3 projecting radially on the outer periphery of a rod-shaped main body 2 at a predetermined pitch in the left-right direction (axial direction), and forming cutting edges 4 on the outer periphery of each blade holder 3. It will be done.

Each of the cutting edges 4 is formed on the outer periphery of the left surface (advance side) of each blade stand 3, and has an outer periphery shape in the axial direction that approximately corresponds to the inner periphery shape of the spline hole. The cutting edges 4 adjacent to each other in the direction are formed such that the cutting edge on the right side (backwards side) has a larger diameter in sequence.

Further, cylindrical guide portions 5 and 6 are integrally formed at both left and right ends of the main body 2.

(Problems to be Solved by the Invention) In the above-mentioned conventional device, the main body 2 and the blade base 3 are integrally formed, which makes it extremely difficult to form and polish each cutting edge 4. The drawback was that it could not be polished.

That is, the front clearance surface (A) and the side clearance surface (B) of each cutting edge 4 have a clearance slope toward the right side, that is, toward the adjacent large-diameter cutting edge 4. When forming and polishing, prepare each front flank (A) for each blade stand 3.
Also, a side relief surface (a) must be formed, resulting in the above-mentioned drawbacks.

Furthermore, when some of the cutting edges are damaged due to a collision with an object, it is extremely difficult to repair them.

The object of the present invention is to obtain a new broach tool structure and a polishing method thereof that eliminate the above-mentioned drawbacks.

(Means for Solving the Problems) In order to achieve the above object, the present invention is configured as follows.

That is, a large number of similar-shaped blade mounts are provided in the axial direction that protrude in the radial direction from the outer periphery of the rod-shaped main body, and a blade row section is formed by forming a cutting edge at the protruding end of each tooth mount; A broaching tool having rod-shaped guide portions extending outward in the axial direction from both ends, a rod-shaped mandrel is provided, and a number of annular and similar-shaped ring tool bases each having a cutting edge formed on the outer periphery thereof are provided, Each ring blade rest is fitted in series to the mandrel to form a blade row,
Rod-shaped guide parts are provided at both ends of the mandrel, and at least one of the guide parts is removably connected to the mandrel, and each guide part tightens and fixes each ring blade seat fitted to the mandrel in the axial direction. It is structured as follows.

Further, each of the ring blade mounts is reversed so that each cutting edge faces in the axial direction opposite to the cutting direction, and the ring blade mounts with larger diameters are sequentially arranged so as to be adjacent to each other in the axial direction opposite to the cutting direction. After the rings are fitted onto the mandrel and each of the ring blades is tightened and fixed in the axial direction by each guide portion, the flank of each cutting edge is polished.

(Function) Since the present invention has the above-mentioned configuration, each ring tool stand is arranged so that each cutting edge faces in the cutting direction, and ring tool stands with larger diameters are successively adjacent to each other in the opposite direction to the cutting direction. By arranging the ring blades as shown in FIG.

In addition, each ring tool holder is reversed so that each cutting edge faces in the axial direction opposite to the cutting direction, and ring tool mounts with larger diameters are sequentially arranged adjacent to each other in the axial direction opposite to the cutting direction. When these rings are fitted onto the mandrel and fixed by tightening in the axial direction at each guide part, the flank of each cutting edge becomes a clearance slope toward the adjacent small-diameter cutting edge, and each flank are arranged approximately on a straight line.

In this state, if the polishing wheel is rotated and moved linearly in the direction in which the flanks are arranged, the flanks will be polished in sequence.

(Example) Embodiments of the present invention will be described below based on the drawings.

In the drawings, FIG. 1 is a sectional view of a main part showing an embodiment of the present invention, FIG. 2 is an enlarged sectional view taken along the line 1--2, and FIG. 3 is a sectional view of a rearranged main part.

In the drawing, B is a broaching tool for forming a spline hole, and has a blade array part 10 in the middle part and a front guide part 15 and a rear guide part 16 at both left and right ends.

The blade row section 10 has a cylindrical mandrel 11 of equal diameter, and a large number of annular ring blade mounts 12 are stacked and fitted in the left and right direction (axial direction) on the outer periphery of this mandrel 1. Ring blade stand 12
A cutting crab 3 is formed on the outer periphery.

- The blade stand (2) is formed to have an inner diameter that closely and slidably fits into the mandrel 11, and its outer periphery is formed in an uneven shape.

In addition, each of the cutting edges ↓ 3 is formed on the outer periphery of the left surface (advance side) of each ring blade stand 12, and its outer periphery shape when viewed from inside in the axial direction is shaped like a spline as shown in FIG. The cutting edges 13 are formed into a tooth shape that approximately corresponds to the inner circumferential shape of the hole, and the cutting edges 13 adjacent to each other in the axial direction are formed such that the cutting edge 13 on the right side (backwards side) has a larger diameter in sequence. .

Further, a small-diameter screw shaft 4 is integrally formed on the left end of the mandrel 11, and this screw shaft 14 is removably screwed into a large-diameter, cylindrical front guide portion 15. A cylindrical rear guide portion 16 with a stepped larger diameter is integrally formed at the right end portion of 11.

Note that if an axial key groove is formed in the fitting portion between the mandrel 11 and each ring blade part 2, and a key is fitted into this key groove, each ring blade part 12 can be aligned in the circumferential direction. It is preferable because it is easy to attach it to the mandrel 11 in synchronization with the process.

Next, the manner of use of the above embodiment will be explained.

First, when processing a workpiece, assemble it as follows.

That is, with the mandrel 11 and the front guide part 15 separated, each ring blade stand 12 is moved so that each cutting edge 13 is on the left side (
The rings are arranged so as to face the cutting direction (cutting direction), and the ring cutting tools 2 of successively larger diameters are arranged so as to be adjacent to each other toward the right and are fitted into the mandrel 11.

Next, the front guide portion 15 is screwed into the threaded shaft 14 of the mandrel 11, and each ring blade stand 12 is tightened and fixed in the axial direction.

As a result, a broach tool B capable of machining a workpiece is formed as shown in the drawing.

Next, when polishing each cutting edge 13, first assemble it as shown in FIG.

That is, with the mandrel 11 and the front guide part 15 separated, each ring blade stand 12 is moved so that each cutting edge 13 is on the right side (
At the same time, the ring blade bases 12 having larger diameters are arranged so as to be adjacent to each other toward the right, and fitted onto the mandrel 11.

Next, the front guide portion 15 is screwed onto the screw shaft 4 of the mandrel 11, and each ring blade stand 12 is tightened and fixed in the axial direction, thereby forming a reverse arrangement broach C.

Then, the front flank (A) and side flank (B) of each cutting crab 3 form a clearance slope toward the adjacent small diameter cutting force direction, that is, toward the front guide portion 15, and each flank in the axial direction (A) and (B) are arranged approximately on a straight line.

Next, as shown in FIG. 3, the reversely arranged brooch C is
The polishing machine (
(not shown), and in this state, the grinding wheel 18 of the grinding machine is mounted on the front flank (A) or the side flank (A).
The polishing wheel 18 is moved linearly in the left-right direction while rotating.

By doing so, each front flank (A) or each side flank (B) adjacent to each other in the axial direction will be polished one after another.

As shown in FIG. 4, in the present invention, a large number of cylindrical ring bodies 20 are formed, and these ring bodies 20 are fitted onto the mandrel 11 in an overlapping manner in the axial direction. The outer peripheral surface 20a of each ring body 20 is tightened and fixed in the axial direction, and in this state, the outer peripheral surface 20a of each ring body 20,
The axial sides 20b and 20c, the outer periphery, etc. are cut and polished, and as shown in Fig. 5, the front flank (A), side flank (B), and rake face ( ), etc. to form a ring blade stand 12' having a cutting edge 13' on the outer peripheral edge of the right side, and then each ring blade stand 12'
The broach tool A as shown in FIG. 1 may be formed by inverting the broach tool A in the axial direction.

(Effects of the Invention) As is clear from the above description, the present invention provides a large number of annular and similar-shaped ring holders having cutting edges formed on the outer periphery, and fits each ring holder in series to the mandrel. Since the blade row part is formed by rotating the ring blades, it is possible to easily obtain various types of broach tools by replacing different types of ring blade holders, and when some of the cutting edges are damaged, Repairs are easy as all you have to do is replace the ring blade stand.

Further, since each blade stand is attached to the mandrel in the opposite direction for polishing, the polishing can be performed with high precision and quickly.

[Brief explanation of drawings]

Fig. 1 is a cross section of the main part showing an embodiment of the present invention, Fig. 2 is an enlarged sectional view taken along the line nn, Fig. 3 is a cross section of the main part in a rearranged state, and Figs. 4 and 5 are the blades. FIG. 6 is a cross-sectional view of the main part showing the forming process of the row part, and FIG. 6 is a cross-sectional view of the main part showing the conventional example. B nib broach tool, 10: Blade row part, 11: Core metal, 12:
Ring blade stand, 13: cutting edge, 14: screw shaft, 15: front guide section, 16: rear guide section, C: reverse arrangement broach tool,
17: Support jig, 18: Polishing whetstone, (A): Front flank,
(A): Side relief surface. Application agent Hisashi Matsumoto

Claims (1)

[Scope of Claims] 1. A blade row section formed by providing a large number of similar-shaped blade mounts in the axial direction that protrude in the radial direction from the outer periphery of a rod-shaped main body, and forming a cutting edge at the protruding end of each tooth mount. and a rod-shaped guide section extending axially outward from both ends of the blade row section, the broach tool has a rod-shaped mandrel and an annular and similar-shaped ring with a cutting edge formed on the outer periphery. A number of blade holders are provided, and each ring blade holder is fitted in series to the mandrel to form a blade row part, and bar-shaped guide parts are provided at both ends of the mandrel, and at least one guide part is attached to the mandrel. The structure of a broach tool is characterized in that each ring blade holder is detachably connected and fitted to a mandrel at each guide portion and is fixed by tightening in the axial direction. 2. Invert each of the ring blade holders so that each cutting edge faces in the axial direction opposite to the cutting direction, and arrange ring blade holders with larger diameters adjacent to each other in the axial direction opposite to the cutting direction. A method for polishing a broach tool, which comprises: fitting the rings into a mandrel, tightening and fixing each of these ring blades in the axial direction with each guide part, and then polishing the flank of each cutting edge.