JP2553150Y2 - Turn brooch - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION This invention relates to a turn broach suitable for machining a journal of a crankshaft, etc.
It relates to improvement of a segment mounting structure.

[0002]

2. Description of the Related Art In recent years, as a method for cutting a crankshaft of a reciprocating internal combustion engine, for example, a continuous cutting method using a turn broach as shown in FIGS. 4 and 5 has been widely adopted. In the turn broach shown in these figures, a plurality of arc-shaped segments 4 are mounted on the outer peripheral portion of the rotating shaft S of the processing machine 2 along the circumferential direction of the rotating shaft S. A plurality of cutting blade tips 6 are fixedly seated. In the turn broach illustrated in FIG. 4, the cutting portions 8 including a plurality of segments 4 arranged in the circumferential direction are provided in five rows along the axial direction of the rotation shaft S. It is sufficient if there is at least one, and it is variously changed according to the workpiece.

The turn broach is provided in such a manner that the axis of the work W attached to the chuck 10 and the axis of the rotary shaft S are parallel to each other. 5 arrow A direction)
While rotating the rotating shaft S at a very low speed in a specific direction (the direction of arrow B in FIG. 5), and the plurality of cutting blades 6 fixedly held on the outer periphery of the turn broach work W
The side cutting of the counter weight C, the width cutting of the journal J, and the diameter machining of the journal J are continuously performed.

[0004] In the above-described turn broach, the mounting structure of each segment with respect to the rotation axis S is conventionally known as shown in FIG.
8 to FIG. That is, each segment 4 having a substantially sector shape in a side view has an inner diameter portion 12 formed in an arc shape, and has a shape in which the segment 4 abuts on the outer peripheral portion of the rotating shaft S without a gap. S
Key grooves 14, 15 extending in an arc shape in side view
Are formed and the key grooves 17, 1 extending linearly are formed.
8 are formed.

A vertical key 16 extending in an arc shape in a side view mounted on the key groove 15 and a horizontal key 20 extending in a straight line mounted on the key groove 18 correspond to the key groove 14 and the key groove of the segment 4. 17, the segment 4 is positioned with respect to the rotation axis S. Thereafter, in this state, the positional relationship between the two is fixed by a plurality of (in this case, four) bolts 22.

[0006]

In the conventional turn broach as described above, the weight of each segment 4 is heavy, the attachment and detachment of the segment 4 is heavy, and the vertical key 16 is curved. However, there is a problem that attaching and detaching the vertical key 16 is troublesome and time-consuming, and the work efficiency is poor. An object of the present invention is to solve the above problems.

[0007]

According to the present invention, a plurality of segments extending in an arc shape are mounted on an outer peripheral portion of a rotating shaft driven to rotate around an axis along a circumferential direction of the rotating shaft. In a turn broach in which a plurality of cutting blade tips are fixedly held along the circumferential direction of the segment on the outer peripheral portion of each segment, the respective inner segments are mounted on the outer peripheral portion of the rotary shaft, An inner segment member that extends linearly, and an outer segment member in which an inner peripheral portion extends linearly and a plurality of cutting blade tips are fixedly held on an outer peripheral portion, and the outer peripheral portion of the inner segment member and the outer segment member A keyway extending linearly is formed in the inner peripheral portion of the outer segment member.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. The turn broach shown in this embodiment has a segment mounting structure (including a segment structure).
The other features are the same as those shown in FIGS. 4 and 5 described above.

In these figures, reference numeral 26 denotes a segment, and the inner segment member 28 and the outer segment member 3
0, and has a sector shape similar to the segment 4 shown in FIG.

The inner segment member 28 includes an inner peripheral portion 32.
Are formed in an arc shape that is attached to the outer peripheral portion of the rotating shaft S without any gap, and extend along the circumferential direction of the rotating shaft S. The inner peripheral part 3
2, a key groove 34 is formed in the circumferential direction along the circumferential direction, and a key groove 36 is also formed in the outer circumferential portion of the rotating shaft S facing the key groove 34 along the circumferential direction.
A vertical key 38 extending in an arc shape is interposed between the vertical keys 36 and 36 (FIG. 3).

The inner peripheral portion 32 of the inner segment member 28
A key groove 40 extending linearly along the axial direction of the rotation axis S is formed in the side central portion of the key groove 40.
A key groove 42 is also formed on the outer peripheral portion of the rotating shaft S facing this. A horizontal key 44 extending linearly is interposed between the key grooves 40 and 42.

Further, four bolt holes 46 are formed in the vicinity of the square of the inner segment member 28, and the tip screw portion of the bolt 48 inserted into each of the bolt holes 46 is connected to the rotation shaft S.
, The inner segment member 28 and the rotation shaft S are fixed to each other.

Further, the outer peripheral portion 50 of the inner segment member 28 is formed in a flat surface extending linearly in a side view, and has a linear shape in the center in the width direction (axial direction of the rotation axis S). An extended keyway 52 is formed.

The outer segment member 30 has an inner peripheral portion 54 having a flat surface which abuts on the outer peripheral portion 50 of the inner segment member 28 without any gap. Similarly to the key groove 52, a key groove 56 extending linearly is formed, and a vertical key 58 extending linearly is interposed between the key grooves 52 and 56. An engaging portion 60 is formed at one end on the inner peripheral side of the outer segment member 30. The engaging portion 60 is formed linearly on the inner segment member 28 along the axial direction of the rotation shaft S. Groove 2
The key 62 inserted into the connector 9 is engaged.

On the inner peripheral side portion of the outer segment member 30,
Four Dharma holes 64 are formed, and each of these Dharma holes 64 is formed.
Is screwed into the inner segment member 28 so that the outer segment member 30 is fixed to the inner segment member 28.

The outer peripheral portion of the outer segment member 30 is formed to have a width smaller than that of the inner peripheral portion, and a plurality of cutting tips 68 are fastened and fixed to both side surfaces by bolts 70. Each of these cutting blade tips 68 is formed by forming a hard material such as a cemented carbide into a substantially rectangular flat plate in appearance.

Note that three holes 72 are formed in the width direction on the side of the center of the outer segment member 30.

In the turn broach according to the above configuration, the inner segment member 28 mounted on the rotation shaft S is common to all the segments 26, and the outer segment member 3
By setting only 0 to various shapes (outer shape, shape, arrangement, etc. of the cutting blade tips 70 to be mounted), the following excellent effects can be obtained.

First, when changing or replacing the segment 26, it is not necessary to remove all the inner segment members 28 once they are mounted on the rotating shaft S.
Only exchange and change can be done. The outer segment member 30 is smaller than the inner segment member 28,
Since the weight is small, the working weight can be remarkably reduced as compared with the case where the conventional segment shown in FIGS. 6 to 8 is used.

Next, when the outer segment member 30 is mounted on the inner segment member 28, the vertical key 58 is not formed to be curved, and is placed on the inner segment member 28 to which the vertical key 58 and the horizontal key 62 are attached. The outer segment member 30 can be easily attached with the key groove 56 fitted into the vertical key 58. Then, the outer segment member 30 is slid along the vertical key 58 and the engaging portion 60 is brought into contact with the horizontal key 62,
The outer segment member 30 can be easily positioned with respect to the inner segment member 28. After this, each bolt 6
By fixing the outer segment member 30 and the inner segment member 28 at 6, the mounting of the outer segment member 30 is completed. Further, the outer segment member 30 can be easily removed by the reverse operation procedure. Therefore, as compared with the conventional case where the vertical keys curved in an arc shape are used, the labor and labor required for the operation of directly detaching the segment 26 can be greatly reduced, and the operation efficiency can be improved.

Further, since the outer segment member 30 is formed with the hole 72, the operator can easily carry the hole using the hole 72.

[0022]

As described above, in the turn broach according to the present invention, each segment has an inner segment mounted on the outer periphery of the rotating shaft and an outer segment extending linearly. Since the inner peripheral portion extends linearly and the outer peripheral portion has an outer segment member in which a plurality of cutting tips are fixedly held, the outer segment member is replaced when the segment is changed or exchanged. And the working weight can be reduced as compared with the conventional case.

Further, since the linearly extending key grooves are formed on the outer peripheral portion of the inner segment member and the inner peripheral portion of the outer segment member, respectively, the outer segment member is easily positioned with respect to the inner segment member. Therefore, the labor and labor required for the work of directly detaching the segment can be greatly reduced, and the working efficiency can be improved.

[Brief description of the drawings]

FIG. 1 is a side view of a turn broach according to an embodiment of the present invention.

FIG. 2 is a view as seen from an arrow II in FIG. 1;

FIG. 3 is a view as seen from the direction of arrow III in FIG. 1;

FIG. 4 is a perspective view showing a general processing method using a turn broach.

FIG. 5 is a schematic side view of the turn broach of FIG. 4;

FIG. 6 is a side view of a conventional turn broach.

FIG. 7 is a view as seen from the direction of arrows VII in FIG. 6;

FIG. 8 is a view as seen from the direction of the arrow VIII in FIG. 6;

[Explanation of symbols]

 26 Segment 28 Inner Segment Member 30 Outer Segment Member 52 Keyway (Inner Segment Member) 56 Keyway (Outer Segment Member) 58 Vertical Key 68 Cutting Edge Tip S Rotating Axis

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor: Satoshi Shirai, 1511 Furamagi, Ishishita-cho, Yuki-gun, Ibaraki Pref.

Claims (1)

(57) [Scope of request for utility model registration] 1. A plurality of segments extending in an arc shape are mounted on an outer peripheral portion of a rotating shaft driven to rotate around an axis along a circumferential direction of the rotating shaft. In the turn broach in which the cutting edge tip is fixedly held along the circumferential direction of the segment, the inner segment member is attached to the outer peripheral portion of the rotating shaft, and the outer peripheral portion extends linearly. And an outer segment member in which an inner peripheral portion extends linearly and a plurality of cutting blade tips are fixedly held on an outer peripheral portion. The outer peripheral portion of the inner segment member and the inner peripheral portion of the outer segment member And a key groove extending linearly.