JP2021133792A - Trans-axle structure - Google Patents

Abstract

To provide a trans-axle structure capable of reducing cost without increasing the number of breathers used even when a speed reduction mechanism chamber and a differential chamber are separated into two chambers.SOLUTION: A trans-axle housing 20 has a speed reduction mechanism chamber 51 accommodating a speed reduction mechanism 50, and a differential chamber 71 accommodating a differential mechanism 70, and the speed reduction mechanism chamber 51 and the differential chamber 71 are partitioned by a partition wall 61. In addition, a ventilation passage 30 is arranged so as to straddle the speed reduction mechanism chamber 51 and the differential chamber 71, and communicates with the speed reduction mechanism chamber 51 and the differential chamber 71. A breather 40 is provided in the ventilation passage 30, and communicates the ventilation passage 40 with the outside of the trans-axle housing 20 as the internal pressure of one or both of the speed reduction mechanism chamber 51 and the differential chamber 71 increases. Thereby, it is possible to provide a trans-axle structure 11 capable of inhibiting the internal pressure of the speed reduction mechanism chamber 51 and the differential chamber 71 from becoming too high with one breather 40.SELECTED DRAWING: Figure 2

Description

The present invention relates to a vehicle transaxle structure. More specifically, it relates to a transaxle structure with a breather.

Conventionally, in a transaxle, oil filled in a housing is scraped up and splashed in order to lubricate a gear or a shaft in the housing (for example, Patent Document 1). The transaxle of Patent Document 1 shares the oil on the differential gear side and the oil on the transmission side.

Japanese Unexamined Patent Publication No. 2016-11734

A transaxle as in Patent Document 1 uses a high-viscosity differential oil to lubricate the differential gear. Therefore, there is a problem that the rotational resistance received by the gear on the transmission side becomes large, and the fuel consumption and the electric cost in the electric vehicle or the like deteriorate. On the other hand, when the viscosity of the oil used for the transaxle is reduced, there is a problem that seizure of the differential gear occurs.

As a result of diligent studies by the present inventors in order to solve the above-mentioned problems of the prior art, the transaxle is divided into a differential chamber in which the differential gear is accommodated and a reduction mechanism chamber in which the gear of the transmission is accommodated. I got the finding that it would be good to do it. In this way, the speed reduction mechanism chamber and the differential chamber are separated, and oil such as low-viscosity automatic transmission fluid (also referred to as ATF) is used for the speed reduction mechanism chamber, and high-viscosity differential oil is used for the differential chamber. Therefore, it is conceivable to improve fuel efficiency and electricity cost while suppressing seizure of the differential gear.

By the way, in the transaxle, since the gear rotates inside, the internal pressure rises or the internal pressure drops and becomes a negative pressure. Therefore, if the difference between the internal pressure and the external pressure in the transaxle is not eliminated, there is a problem that the transaxle is damaged or an oil leak occurs. Therefore, a breather as an air vent is provided in order to eliminate the difference between the external pressure and the internal pressure in the transaxle described above.

Based on this knowledge, when the deceleration mechanism chamber and the diff chamber are separated into two chambers as described above, it may be considered that a breather may be provided in each of the deceleration mechanism chamber and the diff chamber. However, in such a configuration, there is a concern that problems such as an increase in manufacturing cost, an increase in weight, and an increase in size may occur because a plurality of breathers are provided.

Therefore, according to the present invention, even when the speed reduction mechanism chamber and the differential chamber are separated into two chambers, problems such as manufacturing cost, weight increase, and upsizing can be suppressed without increasing the number of breathers used. It is an object of the present invention to provide a transaxle structure.

(1) The transaxle structure of the present invention provided to solve the above-mentioned problems is a transaxle structure in which a reduction mechanism and a differential mechanism are arranged in the transaxle housing, and the transaxle housing is , A deceleration mechanism chamber accommodating the deceleration mechanism, a diff chamber accommodating the differential mechanism, a partition wall separating the deceleration mechanism chamber and the diff chamber, and a ventilation path communicating with the deceleration mechanism chamber and the diff chamber. The breather has a breather provided in the air passage, and the breather connects the air passage and the outside of the transaxle housing as the internal pressure of one or both of the speed reduction mechanism chamber and the differential chamber increases. It is possible to communicate with each other, and the ventilation passage is characterized in that it is arranged so as to straddle the speed reduction mechanism chamber and the differential chamber.

In the transaxle structure of the present invention, the reduction mechanism chamber and the differential chamber are separated by a partition wall, and the ventilation path communicating with the reduction mechanism chamber and the differential chamber is arranged so as to straddle the reduction mechanism chamber and the differential chamber. Has been done. Further, the ventilation passage is provided with a breather capable of communicating the ventilation passage with the outside of the transaxle housing when the internal pressure of one or both of the reduction mechanism chamber and the differential chamber rises. Therefore, even when two chambers, a reduction mechanism chamber and a differential chamber, are provided, the pressure difference between the inside and the outside of the transaxle housing can be eliminated with only one breather. As a result, the number of parts can be reduced, so that the transaxle can be reduced in weight, cost, and size, and the man-hours for assembling parts can also be reduced. Further, since the pressure difference between the inside and the outside of the transaxle housing is eliminated, damage to the transaxle and oil leakage can be suppressed.

Further, since the ventilation path is arranged so as to straddle the speed reduction mechanism room and the differential room, the speed reduction mechanism room and the differential room communicate with each other. Therefore, even if either the reduction mechanism chamber or the differential chamber is formed small, the space of the other can be used. As a result, the frequency of opening and closing the breather can be reduced even when either the reduction mechanism chamber or the differential chamber is formed small. Further, since the pressures in the speed reduction mechanism chamber and the differential chamber can be made equal, it is possible to suppress the mixing of oil between the speed reduction mechanism chamber and the differential chamber.

Further, since the speed reduction mechanism chamber and the differential chamber are separated by the partition wall, it is possible to suppress mutual oil mixing between the speed reduction mechanism chamber and the differential chamber. Therefore, different oils can be used in the speed reduction mechanism chamber and the differential chamber. Thereby, for example, by using a low-viscosity ATF in the speed reduction mechanism chamber and using a high-viscosity differential oil in the differential chamber, fuel consumption and electricity cost can be improved.

(2) The transaxle structure of the present invention provided to solve the above-mentioned problems is characterized in that a part of the outer peripheral edge of the partition wall is located inside the ventilation path.

According to this configuration, the inside of the ventilation path can be separated into the reduction mechanism chamber and the differential chamber by a partition wall, so that the oil in the reduction mechanism chamber and the oil in the differential chamber can be prevented from being mixed in the ventilation passage. be able to.

(3) The transaxle structure of the present invention provided to solve the above-mentioned problems is characterized in that ribs are formed on the outer peripheral edge of the partition wall.

According to such a configuration, the ribs on the outer peripheral edge of the partition wall can prevent the oil from splashing into the ventilation path. As a result, it is possible to suppress the oil from being ejected from the breather.
(4) The transaxle structure of the present invention provided to solve the above-mentioned problems is characterized in that the rib has an inclined portion that is tapered toward the outer peripheral edge.

According to such a configuration, since air smoothly flows to the reduction mechanism chamber and the differential chamber along the inclination direction of the inclined portion of the rib, it is possible to effectively suppress the increase in the internal pressure of the reduction mechanism chamber and the differential chamber. can. In addition, the ribs can prevent oil from splashing into the air passage. As a result, it is possible to suppress the oil from being ejected from the breather.

(6) The transaxle structure of the present invention provided to solve the above-mentioned problems is characterized in that a chamfered portion having a shape along the inclined portion is formed in the air passage.

According to such a configuration, since the air flows smoothly along the inclined direction of the inclined portion and the chamfered portion, it is possible to effectively suppress the increase in the internal pressure of the reduction mechanism chamber and the differential chamber.

According to the present invention, even when the speed reduction mechanism chamber and the differential chamber are separated into two chambers, problems such as manufacturing cost, weight increase, and upsizing can be suppressed without increasing the number of breathers used. Transaxle structure can be provided.

It is the schematic which looked at the transaxle structure of this invention from the plane direction. It is a conceptual diagram which side-viewed the transaxle structure of this invention. FIG. 1 is a cross-sectional view taken along the line AA in FIG. FIG. 1 is a cross-sectional view taken along the line BB in FIG. FIG. 2 is an enlarged cross-sectional view of a main part of the transaxle structure of the present invention in FIG. (A) and (b) are explanatory views which show the installation example of the ventilation path and the partition wall in the transaxle structure of this invention. It is a conceptual diagram which shows another embodiment in the transaxle structure of this invention.

Hereinafter, an embodiment of the transaxle structure 11 of the present invention will be described in detail with reference to FIGS. 1 to 5. It should be noted that the shape is simplified for ease of explanation.

As shown in FIG. 1, the transaxle 10 is mounted on the vehicle 1. A motor 2 (also referred to as a power source) or the like is connected to the rear side of the transaxle 10. The transaxle 10 and the motor 2 constitute a drive device 3 of the vehicle 1.

The drive device 3 is arranged on the front side of the vehicle 1, for example, and can transmit the rotational power output from the motor 2 to the pair of drive shafts 82 via the reduction mechanism 50. Each drive shaft 82 is connected to a pair of drive wheels 80, and the vehicle 1 travels by driving the drive wheels 80 via the drive shafts 82. As the motor 2, a motor generator having a power generation function in addition to a motor function that outputs power for traveling the vehicle toward the drive wheels 80 is used.

As shown in FIG. 1, the transaxle 10 is said to have the transaxle structure 11 of the present invention. The transaxle structure 11 includes a transaxle housing 20, a ventilation path 30, a breather 40, a reduction mechanism 50, a drive shaft 60, a differential mechanism 70, and the like. The reduction mechanism 50, the drive shaft 60, and the differential mechanism 70 are housed in the transaxle housing 20. Further, the transaxle housing 20 includes a speed reduction mechanism chamber 51 that houses the speed reduction mechanism 50 and a differential chamber 71 that houses the differential mechanism 70. In this embodiment, a vertical installation type in which the motor 2 and the transaxle structure 11 are arranged in series will be described as an example.

The speed reduction mechanism 50 is housed inside a speed reduction mechanism chamber 51 formed on the rear side of the transaxle housing 20. Further, the reduction gear 50 includes an input gear 52, a drive gear 53 as an output side gear, a defling gear 73, and the like.

As shown in FIG. 1, the input gear 52 is formed around the axis L1 in the intermediate portion of the input gear shaft 52a. The input gear shaft 52a is provided along the front-rear direction (horizontal direction in the drawing) in the reduction mechanism chamber 51. Both ends of the input gear shaft 52a are rotatably supported by a support wall in the reduction mechanism chamber 51. A motor shaft (not shown) of the motor 2 is connected to the rear end side of the input gear shaft 52a. Therefore, the power of the motor 2 is input to the input gear shaft 52a.

The drive gear 53 is formed around the axis L2 in the intermediate portion of the drive gear shaft 53a. The drive gear shaft 53a is arranged so as to be parallel to the input gear shaft 52a. The rear end side of the drive gear shaft 53a is rotatably supported on the support wall of the reduction mechanism chamber 51 via a bearing 57. A spline fitting portion 56, which will be described later, is formed on the front end side of the drive gear shaft 53a, and the spline fitting portion 56 is rotatably supported by the inner wall of the transaxle housing 20. The drive shaft 60 is formed by connecting a drive gear shaft 53a and a differential shaft 74a, which will be described later. Further, the input gear 52 and the drive gear 53 are engaged with each other, and the rotational power of the motor 2 is transmitted from the input gear 52 to the drive gear 53.

FIG. 2 is a conceptual diagram of the transaxle structure 11 of the present invention as viewed from the side. As shown in FIG. 2, the speed reduction mechanism chamber 51 is injected with oil 62a such as low-viscosity ATF so as to lubricate the housed drive gear 53 and the like. Although details will be described later, in the present embodiment, the speed reduction mechanism chamber 51 and the differential chamber 71 are separated by a partition wall 61 (also referred to as an oil seal 61), and the oil 62a flows into the differential chamber 71 side. Is suppressed.

As shown in FIG. 1, the differential mechanism 70 is housed inside a differential chamber 71 formed on the front side of the speed reduction mechanism chamber 51. Further, the differential mechanism 70 includes a differential shaft 74a, a differential gear mechanism 72, a differential ring gear 73, and the like.

The differential shaft 74a is provided with an intermediate gear 74 on the front end side. Further, the differential shaft 74a is provided on the coaxial line with the axis L2 of the drive gear shaft 53a.

FIG. 3 is a cross-sectional arrow view seen from the direction AA of FIG. As shown in FIG. 3, the differential shaft 74a is connected to the front end side of the drive gear shaft 53a by spline fitting. As a result, the spline fitting portion 56 is formed on the rear end side of the differential shaft 74a. Further, the differential shaft 74a has a constricted portion 74b formed with a small diameter between the intermediate gear 74 and the spline fitting portion 56.

As shown in FIG. 1, the spline fitting portion 56 is located at the boundary portion between the reduction mechanism chamber 51 and the differential chamber 71, and the outer peripheral portion is rotatable on the inner wall of the transaxle housing 20 via the bearing 57. It is supported. Further, the partition wall 61 is fitted on the outer circumference of the differential shaft 74a so as to be located on the constricted portion 74b formed on the differential shaft 74a. By forming the constricted portion 74b, the position of partitioning by the partition wall 61 on the constricted portion 74b can be easily changed. As a result, the versatility of the transaxle structure 11 can be increased, and the degree of freedom in design can be increased.

Further, the spline fitting portion 56 integrates the differential shaft 74a and the drive gear shaft 53a to form the drive shaft 60. The drive shaft 60 can transmit the rotation of the input gear shaft 52a to the drive wheels 80 via the reduction mechanism 50, the differential gear mechanism 72, and the drive shaft 82.

As shown in FIG. 1, the front end side and the intermediate portion of the differential shaft 74a are rotatably supported by taper roller bearings 55 (also referred to as tapered roller bearings 55), respectively. In this way, by rotatably supporting one or both of the differential shaft 74a and the drive gear shaft 53a connected by the spline fitting with the taper roller bearing 55, the twisting force generated in the spline fitting portion 56 is generated. Can be resolved. As a result, the strength of the spline fitting portion 56 can be maintained, and damage to the differential shaft 74a and the drive gear shaft 53a can be suppressed.

As described above, by supporting the drive shaft 60 by the plurality of tapered roller bearings 55 and the plurality of bearings 57, the load supporting the drive shaft 60 can be dispersed. Therefore, the taper roller bearing 55 and the bearing 57 can be miniaturized, and the loss torque of these bearings 55 and 57 when no load can be reduced can be reduced. Thereby, the fuel consumption and the electricity cost of the vehicle 1 can be improved.

The intermediate gear 74 meshes with the differential gear 73 of the differential gear mechanism 72. As a result, the reduction mechanism 50 can reduce the output of the motor 2 and transmit it to the differential gear mechanism 72.

The differential gear mechanism 72 includes a differential gear 73. Further, in the differential gear mechanism 72, a pair of drive shafts 82 are supported so as to be rotatable around an axis orthogonal to the drive shaft 60. A drive wheel 80 is connected to the drive shaft 82. The differential gear mechanism 72 distributes and transmits the power of the motor 2 transmitted to the differential gear 73 to each of the pair of drive wheels 80. Further, when a rotation difference occurs between the pair of drive wheels 80, the differential gear mechanism 72 transmits power while absorbing the rotation difference.

FIG. 4 is a cross-sectional arrow view seen from the direction BB of FIG. As shown in FIG. 4, the partition wall 61 is formed in a circular donut shape, and the outer peripheral edge is in contact with the inner wall of the transaxle housing 20. As a result, the differential chamber 71 and the speed reduction mechanism chamber 51 are separated from each other via the partition wall 61. When the partition wall 61 is provided on the drive shaft 60, the partition wall 61 may be formed in a circular donut shape as described above and fixed around the axis of the drive shaft 60 by press fitting or the like. When the partition wall 61 has another shape, the drive shaft 60 may be inserted through the partition wall 61 so that the drive shaft 60 can rotate with respect to the partition wall 61.

Here, as the partition wall 61, for example, one formed of nitrile rubber, fluorine rubber, silicone rubber, resin or the like can be used. It is desirable to use a partition wall 61 having oil resistance to the oil 62 to be used.

As shown in FIG. 2, the differential chamber 71 is injected with oil 62b such as a relatively high-viscosity differential oil in order to lubricate the differential gear mechanism 72, the differential shaft 74a, and the like. The oil 62b is suppressed from flowing into the speed reduction mechanism chamber 51 by the partition wall 61. The partition wall 61 is allowed to rotate integrally with the differential shaft 74a while being in contact with the inner wall of the transaxle housing 20.

As described above, in the present embodiment, the speed reduction mechanism chamber 51 and the differential chamber 71 are separated by the partition wall 61, and different oils 62a and 62b are stored in the speed reduction mechanism chamber 51 and the differential chamber 71. be able to. Therefore, low-viscosity oil 62a may be used in the region where rotational resistance is desired to be reduced, such as the reduction mechanism chamber 51, and high-viscosity oil 62b may be used in the region where a large load is applied to the gear, such as the differential chamber 71. can. As a result, the rotational resistance of the transaxle 10 can be reduced, so that the fuel consumption and electricity cost of the vehicle 1 can be improved. Further, since the high-viscosity oil 62b can be used on the differential chamber 71 side, seizure of the differential mechanism 70 can be suppressed.

FIG. 5 is an enlarged cross-sectional view of the periphery of the ventilation passage 30 and the breather 40 in FIG. As shown in FIG. 5, a ventilation path 30 is formed on the upper side of the partition wall 61 so as to straddle the reduction mechanism chamber 51 and the differential chamber 71, and the reduction mechanism chamber 51 and the differential chamber 71 are connected to each other. Communicating. The air passage 30 can be formed by making a hole in the inner wall of the transaxle housing 20, processing a part of the inner wall, or molding. Further, the ventilation passage 30 is provided with a breather 40 on the upper side of the partition wall 61, and the ventilation passage 30 communicates with the outside of the transaxle housing 20 via the breather 40.

In the present embodiment, the ventilation passage 30 and the breather 40 are located on the extension line of the partition wall 61. The positions of the ventilation passage 30 and the breather 40 do not have to be located on the extension line of the partition wall 61. In such a case, the ventilation path 30 may be formed or the breather 40 may be provided so that the space on the side where the internal pressure of the reduction mechanism chamber 51 and the differential chamber 71 is likely to increase is widened.

The breather 40 has a tubular portion 42 and a cap 41. In the breather 40, a cap 41 is formed at the upper end of the tubular portion 42, and the claw 41a is engaged with the tubular portion 42. Further, the cap 41 has a gap formed between the cap 41 and the tubular portion 42, and the tubular portion 42 and the outside communicate with each other. Further, an elevating plate 43 is provided at the upper end of the tubular portion 42 to close the opening of the upper end portion of the tubular portion 42. The elevating plate 43 is urged downward by a spring 44 provided in the cap 41 in the vertical direction, and can be raised against the spring 44.

That is, the breather 40 has a structure in which the elevating plate 43 rises as shown by the alternate long and short dash line 43 when the internal pressure of the portion communicating with the tubular portion 42 increases, and the air inside is discharged to the outside. Therefore, the internal pressure between the speed reduction mechanism chamber 51 and the differential chamber 71 is kept constant via the breather 40. As a result, it is possible to prevent the oils 62a and 62b from leaking from the transaxle 10. Further, even if the ventilation passage 30 is formed straddling between the speed reduction mechanism chamber 51 and the differential chamber 71, the internal pressure is kept constant, so that the oil 62a and the oil 62b are mixed with each other. It can be suppressed. As a result, even if one of the reduction mechanism chamber 51 and the differential chamber 71 is formed small, the space can be widely used. Therefore, it is possible to suppress the unilateral increase in the internal pressure of the smaller space.

In the present embodiment, the breather 40 is located on the upper side on the extension line of the partition wall 61, but it may be provided at any position of the ventilation path 30. In order to keep the internal pressures of the reduction mechanism chamber 51 and the differential chamber 71 even, it is desirable to arrange them on the extension line of the partition wall 61.

The above is one embodiment of the transaxle structure 11 of the present invention. Next, another embodiment of the transaxle structure 11 of the present invention will be described in detail below based on FIGS. 6 (a) and 6 (b).

FIG. 6A shows a transaxle structure 11 when a part of the partition wall 61 is located inside the ventilation passage 30. With such a configuration, the inside of the ventilation passage 30 can be separated into the speed reduction mechanism chamber 51 side and the differential chamber 71 side by the partition wall 61. Therefore, the oil 62a and the differential chamber of the speed reduction mechanism chamber 51 can be separated in the ventilation passage 30. It is possible to prevent the oil 62b of 71 from being mixed with each other.

In the present embodiment, if a groove is formed on the inner wall of the transaxle housing 20 along the outer peripheral edge of the partition wall 61 so that the groove and the partition wall 61 are in contact with the inner wall of the transaxle housing 20. good. Further, the ventilation path 30 may be formed in a part of the groove. With the above configuration, a part of the partition wall 61 can be positioned inside the ventilation passage 30, and the partition wall 61 can be allowed to rotate while being in contact with the inner wall of the transaxle housing 20. As a result, mutual oil inflow between the speed reduction mechanism chamber 51 and the differential chamber 71 is suppressed.

FIG. 6B shows a transaxle structure 11 in the case where a rib 61a projecting in the width direction of the partition wall 61 is formed on the outer peripheral edge of the partition wall 61. The rib 61a suppresses the oil 62a and the oil 62b from entering the ventilation passage 30.

In the present embodiment, the rib 61a is formed so as to be tapered toward the outer peripheral edge, and has an inclined portion 61b having a trapezoidal cross section. A chamfered portion 20a is formed at a portion of the ventilation path 30 facing the inclined portion 61b. As a result, the air flow in the ventilation passage 30 can be rectified while suppressing the oils 62a and 62b from entering the ventilation passage 30 on the lower surface side of the rib 61a. Therefore, the internal pressure of the reduction mechanism chamber 51 and the differential chamber 71 can be adjusted more smoothly.

Next, another embodiment of the transaxle structure 11 in which the partition walls 61 are arranged at different positions will be described in detail below with reference to FIG. The same reference numerals are used for the same members as those in the above-described embodiment. Moreover, the description of the same part as the above-described embodiment will be omitted.

As shown in FIG. 7, in the present embodiment, the partition wall 61 is fitted in the outer peripheral portion of the spline fitting portion 56. Further, on the upper side of the partition wall 61, the ventilation passage 30 is formed so as to straddle the speed reduction mechanism chamber 51 and the differential chamber 71. Further, a breather 40 is provided on the ventilation path 30. Therefore, similarly to the above-described embodiment, it is possible to eliminate the excessive increase in the internal pressure between the speed reduction mechanism chamber 51 and the differential chamber 71 via the breather 40. Further, the internal pressure between the speed reduction mechanism chamber 51 and the differential chamber 71 is kept constant. Therefore, even if the ventilation path 30 is formed straddling between the speed reduction mechanism chamber 51 and the differential chamber 71, the oil 62a in the speed reduction mechanism chamber 51 and the oil 62b in the differential chamber 71 may be mixed with each other. No. The position where the partition wall 61 is provided can be changed to an appropriate position in consideration of lubrication of the tapered roller bearing 55, the bearing 57, and the like.

A breather 40 is connected to the air passage 30 so as to be located above the partition wall 61. By providing the partition wall 61 on the outer peripheral portion of the spline fitting portion 56 in this way, it is possible to prevent the force applied to the drive shaft 60 in the twisting direction from reaching the partition wall 61. As a result, the life of the partition wall 61 can be extended.

Further, the partition wall 61 partitions between the spline fitting portion 56 and the inner wall of the transaxle housing 20. As a result, the speed reduction mechanism chamber 51 and the differential chamber 71 are separated from each other, so that mutual oil inflow between the speed reduction mechanism chamber 51 and the differential chamber 71 is suppressed.

The above is the embodiment of the transaxle structure 11 of the present invention, but the present invention is not limited to the above-described embodiment, and appropriate modifications can be made within the scope of the invention.

In the present embodiment, the speed reduction mechanism chamber 51 and the differential chamber 71 are separated by a partition wall 61, but the partition wall 61 is removed so that the speed reduction mechanism chamber 51 and the differential chamber 71 communicate with each other. You can also. The transaxle structure 11 of the present invention can be operated without changing other structures even when the partition wall 61 is removed. When the partition wall 61 is removed and used, it is desirable to use low-cost oil 62 such as differential oil in the reduction mechanism chamber 51 and the differential chamber 71. By injecting the low-cost oil 62 in this way, the cost of the vehicle 1 can be reduced.

Further, by adopting a structure in which the speed reduction mechanism chamber 51 and the differential chamber 71 are separated by a partition wall 61, the structure of the transaxle structure 11 can be easily changed by removing the partition wall 61 according to the purpose of use of the vehicle 1. be able to. As a result, the transaxle structure 11 can be generalized, so that the design of the vehicle 1 can be shared. Therefore, the design cost and the manufacturing cost can be reduced.

Further, the shape and material of the partition wall 61 are not limited to the above-described embodiment. The shape of the partition wall 61 can be appropriately changed according to the shape of the inner wall of the transaxle housing 20 and the shape of the drive shaft 60. Further, in the present embodiment, the partition wall 61 is assumed to rotate integrally with the drive shaft 60. For example, the partition wall 61 is fixed to the inner wall of the transaxle housing 20, and the drive shaft 60 is in contact with the partition wall 61. However, it may rotate.

Further, the shape of the ventilation passage 30 is not limited to the above-described embodiment, and is formed into various shapes as long as it is arranged so as to straddle the speed reduction mechanism chamber 51 and the differential chamber 71. Is possible. The shape of the ventilation passage 30 may be an appropriate shape such as a hole or a groove according to the position where the partition wall 61 is formed, the shape of the inner wall of the transaxle housing 20, and the like. Further, the position where the ventilation path 30 is formed does not have to be on the extension line where the partition wall 61 is arranged. In such a case, the ventilation path 30 may be formed so that the space on the side where the internal pressure tends to increase becomes large.

Further, the structure and shape of the breather 40 are not limited to the above-described embodiment, and various structures and shapes can be used as long as the pressure can be adjusted by communicating the inside and outside of the transaxle housing 20. It is possible to adopt it. Further, the position where the breather 40 is provided does not have to be located on the extension line of the partition wall 61, and can be provided at an appropriate position in the ventilation path 30. That is, the ventilation passage 30 can be provided at various positions as long as it can communicate with the outside of the transaxle housing 20. In such a case, it is desirable that the breather 40 is provided at a position on the side where the internal pressure is likely to increase.

In the present embodiment, a part of the outer peripheral edge of the partition wall 61 is located inside the ventilation passage 30, but the partition wall 61 may be located outside the ventilation passage 30. In this case, it is desirable that the ventilation passage 30 and the partition wall 61 are brought close to each other so that the air from the reduction mechanism chamber 51 and the differential chamber 71 can easily flow into the ventilation passage 30.

In the present embodiment, the rib 61a is formed on the outer peripheral edge of the partition wall 61, but the partition wall 61 may not be provided with the rib 61a. Further, when the rib 61a is provided on the partition wall 61, the size and shape of the rib 61a can be various. For example, the rib 61a can have various shapes such as a rectangular shape, a triangular shape, a circular shape, and an elliptical shape. Further, the position where the rib 61a is provided is not limited to the outer peripheral edge as long as the oil 62a and 62b can be prevented from entering the ventilation passage 30. Further, the inclination angle and shape of the inclined portion 61b can be changed as appropriate. Further, when the chamfered portion 20a is formed in the ventilation passage 30, the shape and the inclination angle of the chamfered portion 20a can be appropriately changed according to the shape of the inclined portion 61b.

Further, various shapes can be adopted depending on the shape and structure of the input gear 52, the drive gear 53, and the differential gear mechanism 72 that also accommodate the shapes of the transaxle housing 20, the reduction mechanism chamber 51, and the differential chamber 71. Further, the arrangement of the reduction mechanism chamber 51 and the differential chamber 71 and the arrangement of the input gear 52, the drive gear 53 and the differential gear mechanism 72 can be appropriately changed within the scope of the invention.

Further, in the present embodiment, the drive shaft 60 connects the drive gear shaft 53a and the differential shaft 74a by spline fitting, but the transaxle structure 11 of the present invention is not limited to this, and the drive shaft 60 is not limited to this. May be integrally formed. Further, the drive shaft 60 may be formed by connecting a plurality of shafts of two or more. Further, the connection between the drive gear shaft 53a and the differential shaft 74a is not limited to the spline fitting method, and various connection methods can be adopted.

In the present embodiment, the partition wall 61 provided on the constricted portion 74b and the partition wall 61 provided on the spline fitting portion 56 are illustrated, but the present invention is not limited thereto. The partition wall 61 can be arranged at various positions as long as it can separate the speed reduction mechanism chamber 51 and the differential chamber 71.

In the present embodiment, the differential shaft 74a and the drive gear shaft 53a are rotatably supported by a plurality of bearings 55 and 57, respectively, but the number of bearings 55 and 57 may be one. It is desirable to use two or more bearings 55, 57 in order to disperse the load applied to the bearings 55, 57 to make the bearings 55, 57 smaller, thereby reducing the torque loss when there is no load. Further, when the spline fitting portion 56 is provided, it is desirable to use the taper roller bearing 55. By using the taper roller bearing 55, it is possible to eliminate the twisting force at the connecting portion of the spline fitting portion 56.

In the present embodiment, as the oil 62 to be injected into the differential chamber 71 and the speed reduction mechanism chamber 51, oil 62 having an appropriate viscosity can be used depending on the purpose of use of the vehicle 1. Examples of the purpose of use of the vehicle 1 include emphasis on cost, emphasis on fuel consumption and electricity cost, and the like. Further, the injection amount of the oil 62 can be changed as appropriate.

It should be noted that the present invention is not limited to those illustrated in the above-described embodiments and modifications, and it is possible to those skilled in the art that there may be other embodiments from the teaching and spirit within the scope of the claims. It will be easy to understand.

INDUSTRIAL APPLICABILITY The present invention can be suitably used in various vehicles such as gasoline-powered vehicles, diesel-powered vehicles, hybrid vehicles, and electric vehicles equipped with a trans-axle. The present invention can be suitably used in a vehicle that employs a longitudinal transaxle.

1: Vehicle 2: Motor (power source)
10: Transaxle 11: Transaxle structure 20: Transaxle housing 20a: Chamfered part 30: Ventilation path 40: Breather 50: Reduction mechanism 51: Reduction mechanism room 53: Drive gear 53a: Drive gear shaft 55: Tapered roller bearing (tapered roller bearing) Roller bearing)
56: Spline fitting part 60: Drive shaft 61: Partition wall (oil seal)
61a: Rib 61b: Inclined part 62: Oil 62a: Oil 62b: Oil 70: Differential mechanism 71: Diff chamber 72: Differential gear mechanism 73: Diff ring gear 74a: Diff shaft 74b: Constriction

Claims (2)

It is a transaxle structure in which a deceleration mechanism and a differential mechanism are arranged in the transaxle housing.
The transaxle housing is
A deceleration mechanism room accommodating the deceleration mechanism and
A differential chamber accommodating the differential mechanism and
A partition wall that separates the speed reduction mechanism chamber and the differential chamber,
A ventilation path communicating with the speed reduction mechanism chamber and the differential chamber,
With a breather provided in the air passage,
The breather
As the internal pressure of one or both of the speed reduction mechanism chamber and the differential chamber increases, the ventilation path and the outside of the transaxle housing can be communicated with each other.
The ventilation path
A transaxle structure characterized in that it is arranged so as to straddle the speed reduction mechanism chamber and the differential chamber. The transaxle structure according to claim 1, wherein a part of the outer peripheral edge of the partition wall is located inside the air passage.

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