JPH024806B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] This invention particularly relates to a method of manufacturing a pawl clutch with a slip-out prevention mechanism, in which the clutch mechanism is constituted by an internal gear and an external gear.

[Conventional technology]

As shown in FIG. 5, a conventional pawl clutch has an external gear 2 that is slidable in the axial direction of a spline shaft 1, a circumferential groove 3 is formed in the external gear 2, and a clutch fork 4 is formed in the circumferential groove 3. is engaged, and the sliding operation of the external gear 2 is performed by the rocking movement of the clutch fork 4 in the direction of arrow A. Further, an internal gear 5 is rotatably disposed at the end of the spline shaft 1.
A spur gear 6 to transmit rotational force is fixed to the internal gear 5.

[The problem that the idea aims to solve]

The internal gear 5 of the conventional pawl clutch as described above is
Since the tooth thickness of the internal teeth 5' is formed almost parallel to the spline shaft 1, when the internal and external gears 5 and 2 are meshed by operating the clutch fork 4, the meshing state is maintained. No such axial force occurs. Therefore, due to rattling due to the tolerance between the internal and external gears 5 and 2 or the external gear 2 and the spline shaft 1, and vibrations and shocks during the transmission of rotational force,
The clutch sometimes slips out, and if the clutch slips out on a mountain trail, it is extremely dangerous.

[Means to solve the problem]

This invention has been made in view of the above-mentioned circumstances, and the internal teeth of the internal gear of a pawl clutch, which is formed by disposing an internal gear and an external gear so that they can mesh with each other, are drilled using a drilling machine. After drilling several small holes having a diameter equal to the valley width of the internal teeth at intervals of the pitches of the internal teeth on the circumference of the pitch circle, use a lathe to drill holes with the diameter of the pitch circle. In the method for manufacturing a pawl clutch, the small hole is drilled at a constant angle with the shaft of the drill of the drill processing machine as the central axis of the internal gear. This invention proposes a method of manufacturing a pawl clutch with a pull-out prevention mechanism, characterized in that the thickness of the internal teeth of the internal gear is tapered toward the direction in which the external gear is engaged.

[Effect]

In other words, this invention aims to orient the thickness of the internal teeth of the internal gear in the direction in which the external gear meshes with the internal gear so that when the internal and external gears mesh, an axial force is generated to maintain the meshed state. This is a method of manufacturing a pawl clutch with a pull-out prevention mechanism, which is formed into a tapered shape.

〔Example〕

The present invention will be described in detail below based on the accompanying drawings.

FIG. 1 is a cross-sectional view showing the upper half of the pawl clutch with a pull-out prevention mechanism according to the method of the present invention, with 7 indicating a spline shaft supported by the transmission case 7'. An external gear 8 is slidably disposed. A circumferential groove 9 is formed in the external gear 8, and a clutch fork 10 that is swingable in the direction of arrow B is engaged with the circumferential groove 9. Further, at the end of the spline shaft 7, an internal gear 11 that can mesh with the external gear 8 is rotatably disposed. A spur gear 12 to transmit the rotational force of the spline shaft 7 is fixed to the side of the internal gear 11.

FIG. 2 is a front view of the internal gear 11. The internal gear 11 has internal teeth 13 formed therein, and the troughs 14 of the internal teeth 13 are formed in an arc shape. FIG. 3 is a partially enlarged perspective view of the internal gear 11, and reference numeral 15 in the figure indicates the machined surface of the internal gear of the internal gear 11 facing the external gear 8. As shown in FIG. As mentioned above, the trough 14 of the internal tooth 13 has an arc length, and the arc center 16 is
It forms an angle α with respect to the tooth ridge line 17 of the internal tooth 13, and the tooth thickness T of the internal tooth 13 extends from the internal tooth machined surface 15 toward the internal tooth back 18, that is, in the direction in which the external gear 8 is meshed. It is formed into a tapered shape that tapers toward the end. Therefore, the tooth thickness at the internal tooth machined surface 15
The relationship between t′ and the tooth thickness t at the back of the internal tooth 18 is as follows:
The relationship is t'> t.

As shown in Fig. 3, the pitch circle at the inner tooth rear part 18 of the internal gear 11 is Sp, the pitch circle diameter is Dp, the valley width is d, and the pitch is p, and the pitch circle at the internal tooth machined surface 15 is S'p pitch circle diameter is D'p pitch is p', number of teeth of internal gear 11 is N, tooth thickness difference (t'-t)
Let Δt be Δt, and the depth from the internal tooth machined surface be b, and the pitch circle at the back 18 of the internal teeth of the circular gear 11.
Assuming that Sp and the pitch circle S′p of the external gear 8 match, A relationship holds true.

FIG. 4 is a schematic diagram showing a method for manufacturing a pawl clutch according to the present invention. In the figure, reference numeral 19 indicates a loading platform of a drilling machine, and an internal gear 11 as a workpiece is placed on this loading platform 19. will be established. and internal gear 1
A drill 20 with a diameter d of a drill machine is disposed facing the internal tooth machining surface 15 of the drill bit 1. Next, the loading platform 19 is tilted by an angle α with respect to the horizontal plane so that the drill shaft 21 of the drill 20 forms an angle α with respect to the central axis 22 of the internal gear 11. At this time, the drill 20 is inserted into the drill shaft 21 at the depth b from the internal tooth machining surface.
is set so that it intersects with the pitch circle Sp. Then, small holes with a diameter equal to the valley width d and a depth b' are bored on the pitch circle Sp at intervals of the pitch p corresponding to the number of teeth N. Note that the depth b' has the relationship b'=b/cosα. Next, align the central axis 22 of the internal gear 11 with the central axis of the lathe, and use a boring tool or the like to drill a hole with a pitch circle S'p.
is manufactured. The manufacturing method is the same as the conventional method except that the shaft of the drill is tilted by an angle α with respect to the central axis of the gear.

〔Effect of the invention〕

As described above, according to the method for manufacturing a pawl clutch according to the present invention, when the internal and external gears 11 and 8 are engaged, the tooth thickness T of the internal tooth 13 is
Since it is tapered towards the end, an axial force is generated to maintain the meshing state, and therefore,
Internal gear 11 and external gear 8 or spline shaft 7
This prevents the clutch from disengaging due to rattling due to tolerances or vibrations and shocks during rotation transmission, and can be expected to maintain the set clutch firmly even on mountain roads, greatly contributing to ensuring safety while driving. It is possible.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a pawl clutch according to the present invention, FIG. 2 is a front view of the internal gear shown in FIG. 1, and FIG.
The figure is a partially enlarged perspective view of the internal gear shown in Figure 1, and Figure 4 is an enlarged perspective view of the internal gear shown in Figure 1.
The figure is a schematic diagram showing a method of manufacturing a pawl clutch according to the present invention, and FIG. 5 is a sectional view showing a conventional pawl clutch. In the figure, 8... external gear, 11... internal gear, 13... internal tooth, T... tooth thickness, Sp, S'p... pitch circle, d... valley width, p, p'... Pituchi, N...
Number of teeth, Dp, D'p... is pitch circle diameter.

Claims (1)

[Claims] 1. In a pawl clutch consisting of an internal gear and an external gear disposed so as to be freely meshed, the internal teeth of the internal gear are drilled using a drilling machine, and the valleys of the internal teeth are formed on the circumference of the pitch circle of the internal gear. A method for producing a pawl clutch, which is formed by drilling several small holes with a diameter equal to the width of the internal teeth at intervals of the pitches of the internal teeth, and then using a lathe to drill holes with the diameter of the pitch circle. In this step, the tooth thickness of the internal teeth of the internal gear is increased by drilling the small hole with the axis of the drill of the drilling machine at a constant angle as the central axis of the internal gear. A method for manufacturing a pawl clutch with a pull-out prevention mechanism, characterized in that the pawl clutch is formed into a tapered shape toward the direction in which external gears are engaged.