JPH0659635U - 2-way differential clutch - Google Patents

Abstract

(57) [Summary] [Purpose] A two-way differential clutch that can reliably clamp the sprag and obtain a reliable clutch operating condition even under conditions where the oil viscosity is high and the relative speed between the sprag and the rotating shaft is large. For the purpose of providing. [Structure] Cylindrical surface 17 of rotating shaft 1 and input gear 2
Side cylindrical surface 18 with a gap therebetween so as to be rotatable relative to each other, a plurality of sprags 6 are interposed in the gaps, and each sprag 6 is connected to the cylindrical surface 17 on the rotary shaft 1 side and the input side. In a two-way differential clutch configured to be tiltable from a neutral position that does not engage with the cylindrical surface 18 on the gear 2 side to a clutch operating position that engages with the cylindrical surfaces 17 and 18,
Circular surface 6a of the sprag 6 and cylindrical surface 1 of the rotating shaft 1
The surface roughness of at least one of No. 7 is formed in the range of 3S to 12S.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an improvement of a two-way differential clutch.

[0002]

[Prior art and its problems]

 A conventional two-way differential clutch is shown in FIG. 1, which is a longitudinal sectional view, FIG. 2 is a sectional view taken along line AA of FIG. 1, FIGS. The structure is as shown in the figure. In FIG. 1, reference numeral 1 denotes a rotary shaft, which has various step portions on its outer peripheral surface. An output gear 4 is connected to one step of the rotary shaft 1 by a spline 4b. Reference numeral 4a is a tooth provided on the outer periphery of the output gear 4 and meshes with a gear (not shown) on the output side. Reference numeral 17 denotes an outer peripheral cylindrical surface, which is formed in parallel with the input gear 2 at another step portion on the outer periphery of the rotary shaft 1. The input gear 2 has an inner peripheral cylindrical surface 18 and is externally inserted with a gap on the outer peripheral cylindrical surface 17. Reference numeral 2b is a tooth formed on the outer circumference of the input gear 2 and meshes with a gear (not shown) on the engine side.

As seen in the enlarged view of the main part of FIG. 5, a plurality of sprags 6 are arranged at predetermined intervals in the circumferential direction between the inner peripheral cylindrical surface 18 of the input gear 2 and the outer peripheral cylindrical surface 17 of the rotating shaft 1. It is installed in. In the neutral state in which the sprag 6 stands between the opposing cylindrical surfaces 17 and 18, a radial skimmer is formed between the outer diameter side arc surface and the inner diameter side arc surface of the sprag 6 and the cylindrical surfaces 17 and 18. When the cylindrical surfaces 17 and 18 fall from the neutral state in the circumferential direction, the outer diameter side arc surface and the inner diameter side arc surface engage with the opposing cylindrical surfaces 17 and 18. The outer diameter side end portion of the sprag 6 is fitted into the pocket 9a of the outer holding member 9 fixed to the inner peripheral cylindrical surface 18 of the input gear 2 by a method such as press fitting, and the inner diameter side end portion is fitted into the outer holding member 9 It is fitted in a pocket 10a of an inner holding member 10 which is slidably inserted between the rotary shaft 1 and the input gear 2. The dimension between the side surfaces of the outer holding member 9 that face each other in the circumferential direction of the pocket 9a is smaller than the dimension between the side surfaces of the inner holding member 10 that face each other in the circumferential direction. Further, a recess 10b is formed in the center of the side surface of the inner holding member 10 that faces the pocket 10a in the circumferential direction, and the pair of elastic bodies 7 incorporated in the recess 10b form the ends on the inner diameter side of the sprag 6 from both sides. By pressing, the sprag 6 is held in a neutral state as shown in FIG. Here, a leaf spring, a Koly spring, or the like can be used as the elastic body 7. In the figure, H is a hole for discharging iron powder or the like.

Returning to FIG. 1, reference numeral 8 is a sub gear, which is arranged in parallel with the input gear 2. Reference numeral 8a is a tooth provided on the outer circumference of the sub gear 8 and meshes with a gear on the engine side like the input gear 2. The inner holding member 10 is slidably inserted into the inner circumference of the input gear 2 on the inner circumference side of the sub gear 8. The sub gear 8 is pressed by a disc spring 19 between the retaining ring 20 attached to the inner holding member 10 and the side surface of the step portion of the inner holding member 10. The inner peripheral side of the outer holding member 9 is partially notched to provide a notch 11, while the inner holding member 10 is provided with a stopper 1 a projecting at a position facing the notch 11. Reference numerals 12 and 14 are bearings for supporting the rotary shaft 1, 13 is a bearing for supporting the input gear 2, and 15 is a bearing for supporting the inner holding member 10.

The operation of the two-way differential clutch configured as described above will be described. The rotation of the engine side gear is transmitted to the input gear 2 and the sub gear 8 meshing with the rotation of the engine side gear. However, the number of teeth 2b of the input gear 2 is, for example, 53, whereas the number of teeth 8a of the sub gear 8 is set to, for example, 54, and the rotation of the same drive shaft causes the rotation of the sub gear 8 to be the input. It will be later than the rotation of gear 2. Therefore, as shown in FIG. 4, the inner holding member 10 pressed against the sub gear 8 has a differential speed with respect to the rotation of the input gear 2 and the stopper 1 a is provided with the cutout 11 of the outer holding member 9. It rotates relative to the end face. Then, the sprags 6 housed in the pockets 10a of the inner holding member 10 fall down in the rotation direction of the inner holding member 10. Therefore, as shown in FIG. 4, the inner diameter side arcuate surface 6a and the outer diameter side arcuate surface 6b of the sprag 6 engage with the opposing cylindrical surfaces 17 and 18, and the clutch is operable.

Here, when the vehicle is running at a high speed, the output gear 4, that is, the rotation shaft 1 is set to rotate faster than the input gear 2, so that the sprag 6 stands up. It does not slip into the cylindrical surfaces 17 and 18 due to frictional force in the direction. On the other hand, if there is a slip on the drive wheels, the rotation speed on the drive side increases, so the rotation of the input gear 2 becomes faster than the rotation of the output gear 4, that is, the rotary shaft 1, and the clutch operates and the input The rotating force of the gear 2 is transmitted to the rotating shaft 1. After the stopper 1a comes into contact with the wall surface of the notch 11, the inner holding member 10 runs idle with respect to the sub gear 8, so that the sub gear 8 is not damaged. As described above, the clutch operating principle of the sprag 6 due to the differential speed of the sub gear 8 is not related to the direction of rotation of the input gear 2, so that the two-way differential clutch functions effectively even when the vehicle is moving in reverse. It is configured.

In such a two-way differential clutch, the oil temperature is low and the oil viscosity is high when the sprag 6 is tilted and in the clutch operating position, and the rotary shaft 1 and the sprag 6 are engaged relative to each other. When the speed is high, the lubrication state on the meshing surface between the rotary shaft 1 and the sprag 6 is fluid lubrication having an extremely small friction coefficient. Therefore, there is a problem that the rotating shaft 1 and the sprag 6 are hard to be bitten and the clutch is hard to operate. Since the sprag 6 is fitted in the pocket 9a of the outer holding member 9 fixed to the input gear 2, the slip between the input gear 2 and the sprag 6 is not a problem.

[0008]

[Means for Solving the Problems]

 The present invention has been devised in view of the above problems of the prior art, and provides a two-way differential clutch that can operate well even under conditions where the oil viscosity is high and the relative speed between the rotating shaft and the sprag is large. The purpose of this is to dispose a cylindrical surface on the rotating shaft side and a cylindrical surface on the input gear side so that they can rotate relative to each other with a gap, and a plurality of sprags are inserted in the gap. Each sprag can be tilted from a neutral position in which it does not engage with the cylindrical surface on the rotating shaft side and the cylindrical surface on the input gear side to a clutch operating position with which both cylindrical surfaces engage. In the directional differential clutch, the surface roughness of at least one of the arcuate surface of the sprag and the cylindrical surface of the rotating shaft is formed in the range of 3S to 12S.

[0009]

[Action]

 Since the surface roughness between the cylindrical surface of the rotating shaft and the arc surface of the sprag is in the range of 3S to 12S, the lubrication state between the two tends to be boundary lubrication even when the oil viscosity is high. Can be moved to.

[0010]

【Example】

 Hereinafter, an embodiment of the present invention will be described with reference to FIGS. As described in the above-mentioned conventional example, when the inner holding member 10 relatively rotates due to the differential speed, each sprag 6 housed in the pocket 10a of the inner holding member 10 falls in the rotation direction of the inner holding member 10. As shown in FIG. 4, the arcuate surfaces 6a and 6b of each sprag 6 engage with the opposing cylindrical surfaces 17 and 18, and the clutch is operable, but the sprag 6 clamps between the cylindrical surfaces 17 and 18. Must be changed from fluid lubrication to boundary lubrication between the arcuate surface 6a of the sprag 6 and the cylindrical surface 17 of the rotary shaft 1, and the oil temperature is low and the viscosity of the lubricating oil is high. When the relative speed between the rotary shaft 1 and the sprag 6 is high, fluid lubrication is likely to occur, the friction coefficient of the meshing surface between the rotary shaft 1 and the sprag 6 becomes extremely small, and the clutch is ready to operate. Mospula In this example, the surface roughness of the arc surface 6a of the sprag 6 and the cylindrical surface 17 of the rotary shaft 1 is in the range of 3S to 12S so that the boundary lubrication is performed under such conditions. If it is finished within such a range of surface roughness, the lubricating state tends to become boundary lubrication even under conditions of high oil viscosity and high relative speed, and good Each sprag 6 is in a clamped state, and the rotational force of the input gear 2 can be favorably transmitted to the rotary shaft 1 via each sprag 6. Even when the surface roughness of at least one of the arcuate surface 6a and the cylindrical surface 17 is in the range of 3S to 12S, the lubricating state is likely to be boundary lubrication, and a good clamped state can be obtained.

[0011]

[Effect of device]

 The present invention forms the surface roughness of at least one of the arc surface of the sprag and the cylindrical surface of the rotary shaft in the range of 3S to 12S, so that the oil viscosity is high and the relative speed between the sprag and the rotary shaft is large. Even under the conditions, the lubrication state is likely to be boundary lubrication, the slug exhibits a good clamped state, and the two-way differential clutch is reliably operated.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a two-way differential clutch.

FIG. 2 is a sectional view taken along the line AA of FIG.

FIG. 3 is an explanatory view of the action of a two-way differential clutch.

FIG. 4 is an explanatory view of the action of the two-way differential clutch.

5 is an enlarged view of a main part of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 rotating shaft 2 input gear 4 output gear 6 sprags 6a, 6b circular arc surface 8 sub gear 9 outer holding member 10 inner holding member 17 outer cylindrical surface 18 inner cylindrical surface

Claims (1)

[Scope of utility model registration request] 1. A cylindrical surface 17 on the rotary shaft 1 side and a cylindrical surface 18 on the input gear 2 side are disposed so as to be relatively rotatable with a gap, and a plurality of sprags 6 are interposed in the gap, The sprags 6 are tilted from a neutral position where they do not engage with the cylindrical surface 17 on the rotary shaft 1 side and the cylindrical surface 18 on the input gear 2 side to a clutch operating position where they engage with the cylindrical surfaces 17 and 18. In the two-way differential clutch configured to obtain, at least one of the arc surface 6a of the sprag 6 and the cylindrical surface 17 of the rotating shaft 1 has a surface roughness in the range of 3S to 12S. Directional differential clutch.