JP7130331B2 - differential gear - Google Patents

Description

The present invention relates to differential gears.

In vehicles such as automobiles, the power from the drive source is transmitted through the transmission to the differential gear, which converts the power into rotation of the left and right drive shafts. Rotation of the shaft is transmitted to the drive wheels.

The outer shell of the differential gear is composed of a differential carrier and a differential cover. For example, in a differential gear for transmitting power to left and right rear wheels, a differential carrier is open on both front and rear sides, and the opening on the rear side is closed by a differential cover. A ring gear, a pinion shaft, two pinion gears, two side gears, and the like are housed inside the outer shell of the differential gear, and lubricating oil is stored to lubricate them. Therefore, the gap between the differential carrier and the differential cover is sealed with a gasket.

JP 2018-123911 A

A liquid gasket, for example, can be used for the gasket. The liquid gasket forms a thin tacky layer that adheres the differential carrier and differential cover together. Therefore, when the differential cover is removed from the differential carrier, a thin plate-like tool such as a spatula is inserted between the differential carrier and the differential cover, and the differential cover is pried open with the tool. Since this work requires a large amount of force and labor, workers desire an improvement in workability.

SUMMARY OF THE INVENTION An object of the present invention is to provide a differential gear that can be easily separated into a first split body and a second split body that form an outer shell.

In order to achieve the above object, a differential gear according to the present invention is a differential gear in which an outer shell is formed by joining a first split body and a second split body, wherein the first split body or the second split body One side of the divided body is formed with a protrusion that is not hidden but exposed when viewed from the other side.

According to this configuration, when splitting the first split body and the second split body, the protrusion formed on one of the first split body and the second split body can be removed from the other side with a tool such as a hammer. can hit. A stress wave is generated by striking the projection, and the stress wave propagates to the joint surface between the first split body and the second split body. Therefore, even if the first divided body and the second divided body are joined via a gasket having adhesiveness, the first divided body and the second divided body can be easily separated. As a result, it is possible to improve workability when dividing the first divided body and the second divided body.

The protrusion may be formed around a portion of one of the first split body and the second split body that has a joint surface to be joined to the other. With this configuration, the stress wave generated when the protrusion is struck can be efficiently propagated to the joint surface between the first divided body and the second divided body, and the first divided body and the second divided body can be divided. It is possible to further improve the workability at the time of doing.

According to the present invention, the first divided body and the second divided body can be easily divided.

1 is a side view of a power transmission mechanism including a differential gear according to an embodiment of the invention; FIG. It is a rear view of a power transmission mechanism. It is the figure which looked at the vicinity of the lower side of the insertion part of a differential gear from the front side. FIG. 4 is a view of the connecting portion between the differential gear and the drive shaft as seen from the rear side, and shows the state before the drive shaft is removed. FIG. 4 is a rear view of the connecting portion between the differential gear and the drive shaft, showing a state in the middle of the drive shaft extraction work.

BEST MODE FOR CARRYING OUT THE INVENTION Below, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

<Configuration of Power Transmission Mechanism>
FIG. 1 is a side view of a power transmission mechanism 1 including a differential gear 2 according to one embodiment of the invention. FIG. 2 is a rear view of the power transmission mechanism 1 (viewed from the rear of the vehicle).

The power transmission mechanism 1 is a mechanism that is arranged at the rear part of the vehicle and transmits power from a driving source such as an engine to the left and right rear wheels. Power transmission mechanism 1 includes a differential gear 2 and drive shafts 3L and 3R extending leftward and rightward from differential gear 2, respectively, as shown in FIG.

The differential gear 2 includes a differential carrier 11 and a differential cover 12, as shown in FIGS. The outer shell of the differential gear 2 is configured by the differential carrier 11 and the differential cover 12 .

The differential carrier 11 extends in the front-rear direction and is open on both front-rear sides. A drive pinion shaft is housed in the front portion of the differential carrier 11 . The drive pinion shaft extends in the longitudinal direction and is held by a differential carrier 11 so as to be rotatable about its center line. A propeller shaft extending in the longitudinal direction is connected to the front end of the drive pinion shaft via a constant velocity universal joint 13 . A drive pinion gear, which is a bevel gear, is attached to the rear end of the drive pinion shaft so as not to rotate relative to it. A differential case is housed in the rear portion of the differential carrier 11 . The differential case is held by a differential carrier 11 so as to be rotatable about a rotation axis extending in the left-right direction. An annular ring gear centered on the rotation axis of the differential case is fixed to the differential case. A drive pinion gear meshes with the ring gear. A differential pinion shaft extending in a direction orthogonal to the left-right direction is supported in the differential case. of side gears are housed. Each side gear meshes with both of the two differential pinion gears.

The differential cover 12 is fixed to the rear end of the differential carrier 11 with a plurality of bolts 14 and closes the rear end opening of the differential carrier 11 from behind. A gasket 15 seals between the rear end face of the differential carrier 11 and the differential cover 12 . The gasket 15 may be, for example, a hardened liquid gasket applied to the rear end surface of the differential carrier 11 .

As shown in FIG. 2, the right end of the differential carrier 11 is formed with a semi-cylindrical wall 16 that opens rearward. A semi-cylindrical wall portion 17 that opens forward is formed at the right end portion of the differential cover 12 . The walls 16 and 17 have the same curvature, and their ends are butted together to form a flat cylindrical insertion portion 18R. Similarly, at the left ends of the differential carrier 11 and the differential cover 12, a flat cylindrical insertion portion 18L is formed as shown in FIG.

FIG. 3 is a front view of the vicinity of the lower side of the insertion portion 18R.

Projections 21 and 22 are arranged in the front-rear direction on the lower sides of the walls 16 and 17 that constitute the insertion portion 18R. The projection 21 on the front side is formed in a plate shape having a side 23 extending downward from the lower end of the wall portion 16 and a side 24 extending leftward from the lower end of the side 23 . The projection 22 on the rear side is formed in a plate shape having a side 25 extending downward from the lower end of the wall portion 17, a side 26 extending rearward and downward from the lower end of the side 25, and a side 27 extending forward from the lower end of the side 26. . The projection 22 is larger in size than the projection 21 , and the sides 25 , 26 and 27 are not hidden behind the projection 21 and are exposed when viewed from the front side as shown in FIG. 3 .

The left drive shaft 3L includes a shaft portion 31 and a constant velocity universal joint 32, as shown in FIG. The shaft portion 31 extends rightward from the constant velocity universal joint 32, is inserted through the insertion portion 18L, and is connected to the side gear within the differential case so as not to rotate relative to it. The constant velocity universal joint 32 has an outer shape that is 360° rotationally symmetrical and protrudes around the outer peripheral surface of the shaft portion 31 . A space is provided in the left-right direction between the insertion portion 18L and the constant velocity universal joint 32 .

The right drive shaft 3</b>R has a shaft portion 33 and a constant velocity universal joint 34 . The shaft portion 33 extends leftward from the constant velocity universal joint 34, is inserted through the insertion portion 18R, and is connected to the side gear within the differential case so as not to rotate relative to it. The constant velocity universal joint 34 has a 360° rotationally symmetric outer shape and protrudes around the outer peripheral surface of the shaft portion 33 . A space is provided in the left-right direction between the insertion portion 18R and the constant velocity universal joint 34 .

Power from a driving source such as an engine is transmitted to the drive pinion shaft housed in the differential carrier 11 via a propeller shaft. Power transmitted to the drive pinion shaft is transmitted from the drive pinion gear to the ring gear to rotate the differential case. Rotation of the differential case is transmitted to the drive shafts 3L, 3R via the differential pinion shaft, differential pinion gear and side gear. As a result, the drive shafts 3L and 3R are rotated, and the left and right rear wheels are rotated to move the vehicle forward or backward.

<Use of projections>
4A and 4B are views of the vicinity of the projection 22 as seen from the rear side.

The protrusion 22 is used as a fulcrum of the bar 41 when the drive shaft 3R is extracted from the differential gear 2. As shown in FIG. Specifically, the tip of the burl 41 is inserted between the insertion portion 18R of the differential gear 2 and the constant velocity universal joint 34 of the drive shaft 3R, and the tip of the burl 41 is inserted into the insertion portion 18R of the constant velocity universal joint 34. It abuts against surfaces 42 facing in the left-right direction. Then, the intermediate portion of the burl 41 is brought into contact with the tip of the protrusion 22, that is, the angle formed by the side 26 and the side 27, and the burl 41 is rotated starting from the contact point. A force is applied to the constant velocity universal joint 34 .

The constant velocity universal joint 34 has a surface 42 that faces the insertion portion 18R in the left-right direction. Compared to the first line segment 45, the shortest length of the second line segment 46 connecting the point 43 and the tip of the projection 22 is longer, and the inclination of the second line segment 46 in the horizontal direction is greater. Therefore, when the protrusion 22 is used as the fulcrum of the burl 41, the inclination angle of the burl 41 with respect to the horizontal direction is large and , the distance between the tip of the burl 41 and the fulcrum becomes longer, so the tip of the burr 41 is less likely to come off from the constant velocity universal joint 34 .

Further, the protrusion 22 is used as a striking surface when removing the differential cover 12 from the differential carrier 11 . Specifically, the protrusion 22 is larger in size than the protrusion 21, and the sides 25 to 27 are exposed without being hidden behind the protrusion 21 when viewed from the front side. is hit with a hammer, etc. When projection 22 is hit, a stress wave is generated and propagates to the joint surface between differential carrier 11 and differential cover 12 .

<Effect>
As described above, the differential cover 12 is provided with the protrusions 22 . Therefore, when removing the differential cover 12 from the differential carrier 11, the operator can hit the projection 22 from the front side with a hammer. Striking the projection 22 generates a stress wave, which propagates to the joint surface between the differential carrier 11 and the differential cover 12 . Therefore, even if differential carrier 11 and differential cover 12 are joined via gasket 15 made of a liquid gasket, differential cover 12 can be easily removed from differential carrier 11 .

Further, in the operation of extracting the drive shaft 3R from the differential gear 2, the operator inserts the tip of the burl 41 between the insertion portion 18R of the differential gear 2 and the constant velocity universal joint 34 of the drive shaft 3R, and pulls the burl 41. A force can be applied to the constant velocity universal joint 34 by the tip of the burl 41 by the principle of leverage, with the point of contact being the fulcrum, when it is brought into contact with the projection 22 . At this time, the inclination angle of the burl 41 with respect to the direction of the center line of the insertion portion 18R is greater than in the case where the burl 41 is brought into contact with the peripheral edge portion of the distal end surface 44 of the insertion portion 18R and the contact point is used as the fulcrum. Since it is large and the distance between the tip of the burl 41 and the fulcrum is long, the tip of the burl 41 is less likely to come off the drive shaft 3R, and the drive shaft 3R can be easily removed from the differential gear 2.例文帳に追加

<Modification>
Although one embodiment of the present invention has been described above, the present invention can also be implemented in other forms.

For example, in the above-described embodiment, the differential cover 12 is formed with the protrusion 22, and the protrusion 22 is used for pulling out the drive shaft 3R and removing the differential cover 12 as an example. However, not limited to this, the protrusion 21 of the differential carrier 11 may be formed larger than the protrusion 22 of the differential cover 12, and the protrusion 21 may be used for extracting the drive shaft 3R and removing the differential cover 12.

In addition, various design changes can be made to the above configuration within the scope of the matters described in the claims.

2: Differential gear 11: Differential carrier (first divided body/second divided body)
12: Differential cover (second divided body/first divided body)
22: Protrusion

Claims (2)

A differential gear having an outer shell formed by joining a first split body and a second split body,
A plate-shaped first projection is formed on the first divided body along a joint surface with the second divided body,
A plate-like second projection is formed on the second divided body along a joint surface with the first divided body ,
The second projection faces the first projection in the direction in which the first divided body and the second divided body are arranged, is larger in size than the first projection, and is viewed from the first divided body side. The differential gear has a portion exposed without being hidden by the first projection when the differential gear is closed. The first divided body is formed with a semi-cylindrical first wall that opens toward the second divided body,
The second divided body is formed with a semi-cylindrical second wall portion that opens toward the first divided body,
The first wall portion and the second wall portion form a cylindrical insertion portion through which the drive shaft is inserted by abutting the end portion of the first wall portion and the end portion of the second wall portion. compose and
The first projection is provided on the first wall,
2. The differential gear according to claim 1, wherein said second projection is provided on said second wall portion.

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