JPH02311216A - Expanding tool - Google Patents

Abstract

PURPOSE:To process a work gear uniformly by filling urethane rubber for filling each tooth in such a way that it fills only around a work part of each tooth, and that it penetrates into an engagement part bored in the work part. CONSTITUTION:Many tooth members 3 each having a tooth-shaped work part 1 on one side and an inclined surface 2 on the other side are disposed circularly with the inclined surface 2 in for forming a conical hole, and they are planted into urethane rubber 5 filled inside a frame 4. The urethane rubber 5 fills only around the work part 1 of each tooth member 1 without reaching the inclined surface 2. In a side end surface of the work part 1 of the tooth member 3 are bored a throughhole 12 and a concave groove 13, where the urethane rubber 5 penetrates, so the tooth member 3 is installed in the urethane rubber 5 strongly. An arc-like groove 20 is provided at a lower end surface 8 of each tooth member 3 for forming a circular groove, where a plate spring 11 is installed. In this constitution, the tooth members 3 are prevented from being separated, and a work gear is processed uniformly.

Description

Detailed Description of the Invention (Industrial Field of Application) This invention involves machining a stepped portion in an internal gear or spline hole used for torque transmission so that the external gear that meshes with the spline hole does not come out. This article relates to an expanding tool.

(Prior art) Expanding tools that have been used in the past consist of a large number of tooth pieces, each with a processing part formed on one side and an inclined surface formed on the other side, arranged in a ring shape with a slight gap between them. is implanted in the urethane rubber filled in the frame, and a conical punch is moved in and out of the conical hole formed by connecting the sloped surfaces of the tooth pieces, and each tooth piece moves forward and backward in the radial direction as the punch moves. (Utility Model Publication No. 49-37932).

(Problem to be Solved by the Invention) However, with such an expanding tool, the tool is advanced between the adjacent internal teeth (T) of the gear to be machined, and as shown in FIG. Form part (f).

The taper angle (θ) of the stepped portion is the same as the processed portion (11) of each tooth piece (3).
It is difficult to form a stepped portion (f) with good precision because the tooth profile is not uniform and there are large variations from tooth to tooth.

For this reason, internal gears generate noise during rotation, or gear removal may cause an accident.

This problem is caused by the fact that the urethane rubber on which each tooth piece is implanted does not deform uniformly, and there is a difference in thickness between the cutting edge and the base side of each tooth piece, and each tooth piece does not move radially correctly. I think that the.

(Means for solving the problem) Therefore, the present invention takes a machined part as an example, and provides a plurality of tooth pieces each having an inclined surface formed on the other side, arranged in a ring shape with a slight gap between them, and A conical punch is inserted into and out of a conical hole formed by connecting the inclined surfaces of each tooth piece, and is implanted in the urethane rubber filled in the main body, and as the punch moves, each In an expanding tool that allows the teeth to advance and retreat in the radial direction, the urethane rubber fills only the vicinity of the machined part of the tooth and passes through the engagement recess drilled on the machined part side, so that the teeth move in the radial direction. This allows the taper angle (θ) formed on the stepped portion (f) of each gear to be machined (W) to be uniformly machined.

(Function) As shown in Fig. 6, the gear to be machined (W) is installed in a predetermined position, and the conical punch θ4) that is in contact with the conical hole (I5) where the inclined surface (2) of the tool is connected is aligned with the arrow (P a ) direction, each tooth piece (3) spreads out in the radial direction by 1° (not shown by the arrow), forming a step (f) on the internal tooth (T) of the workpiece (W). (See FIGS. 1O and 11). At this time, the urethane rubber, which is thought to be preventing the correct movement of the tooth piece in the radial direction, fills only the processed parts of the tooth piece, so the urethane rubber (5) contracts uniformly and each tooth (T ) The taper angle (θ) of the stepped portion (f) is formed uniformly.

After processing is completed, when the punch is raised by 1 in the direction of the arrow (Pb), the shrinkage force of the urethane rubber (5)
b) Make sure to move back in direction and wait for the next gear to be machined to be inserted into the machining position.

(Example) Next, an example of the present invention will be explained with reference to the drawings. Figs. 1 and 2 show an example of the tool according to the present invention,
- For example, a tooth-shaped processed part (1) and a large number of tooth pieces (3) each having an inclined surface (2) on the other side are arranged in an annular shape with the inclined surface inward to form a conical hole Q51. At the same time, it is implanted in urethane rubber (5) filled in the frame (4).

The urethane rubber (5) fills only the vicinity of the processed portion (11) of each tooth piece (3) and does not reach the inclined surface (2).

This is shown in detail in Figure 3. Urethane rubber (5
) reaches points A and B on the side surfaces of the adjacent tooth pieces, but does not reach the lowest points C and D of the slope (2) of the tooth pieces. Also, when viewed in cross section, as shown in Figure 2, the end surface (7) of the urethane rubber (5) filling the machining part of the tooth piece (3) is the bottom surface (6) of the tool.
) constitutes a perpendicular (A-A'') plane.

In addition, an inclined surface (2
) are drilled through holes 02) and grooves 03), urethane rubber (5) penetrates into the through holes (2) and grooves 03), and the teeth (3) are firmly erected in the urethane rubber. do. Note that the small diameter portion of the through hole α is an air vent.

Further, the lower end surface (8) of each tooth piece (3) is longer than the upper end surface (9) and is provided with an arcuate groove (10), and the groove is formed by arranging the tooth pieces in an annular shape. , a plate spring 0υ is installed in the groove. Plate spring 0υ
is 1 in the direction of advancing each tooth piece (3) radially outward.
to strengthen

By the way, module: 2.6, pressure angle: 20°, number of teeth:
45, Material: 5Cr420, Hardness: Hb159-20
When a step was machined on the internal gear No. 1, the error in the taper angle (θ) of the right tooth flank was 0° to +24°, and the error in the taper angle of the left tooth flank was 0° to +24°.

(Effect) This invention, as described above, arranges a large number of tooth pieces (3) in an annular shape and fills only the vicinity of the processed portion (1) with urethane rubber (5), so the shrinkage difference of the urethane rubber The tooth pieces move correctly in the radial direction without being hindered by the above, and uniform steps are formed on the teeth of each gear to be machined (W). Moreover, the through hole 02) and concave a provided on the processed part side of the tooth piece
Since the urethane rubber (5) is connected to the engaging portion (03), each tooth piece is made of urethane rubber, regardless of whether the urethane rubber fills the tooth-shaped processed portion (1) of the tooth piece. It is securely attached to the rubber and will not separate. Therefore, even if each tooth piece is repeatedly moved in the radial direction, tooth piece (3)
There is no risk of separation.

Since the teeth of the gear are formed with highly accurate stepped portions (f) with little error, the gears that mesh with the stepped portions (f) do not slip out of gear (and the torque is transmitted very smoothly).

[Brief explanation of the drawing]

FIG. 1 is a front view of an embodiment of the present invention, and FIG. 2 is a front view of an embodiment of the present invention.
1-II line, FIG. 3 is a front view of essential parts of the present invention, FIG. 4 is a sectional view of the tooth piece taken along FIG. 3 If-TV line, and FIG. 5 is V-V in FIG. 1. 6 is a half-sectional view showing the situation during machining of the expanding tool of the present invention; FIG. 7 is a partial front view seen from the direction ■ in FIG. 6; The figure is an explanatory diagram showing a stepped portion formed on the tooth (T) of the gear to be machined, and FIG. 9 is a partial perspective view of the gear to be machined with the stepped portion machined. 1... Processing part, 2... Inclined surface, 3... Tooth piece, 4...
...Frame body, 5...Urethane rubber, 12...Through hole (
(engaging part), I3... recess a (engaging part), 14... punch, 15... conical hole. Agent Patent Attorney Jun Kawachi Figure 6 Figure 7 Figure 8

Claims (1)

[Claims] A large number of tooth pieces, each with a tooth-shaped processed part formed on one side and an inclined surface formed on the other side, are arranged in an annular shape with a slight gap between each other, and are placed inside the urethane rubber filled in the frame. Once planted, a conical punch was inserted into and out of the conical hole formed by connecting the inclined surfaces of each tooth piece, allowing each tooth piece to move forward and backward in the radial direction as the punch moved. An expanding tool characterized in that the urethane rubber fills only the vicinity of the machined part of the tooth piece and penetrates into an engaging part drilled on the machined part side.