JP7439624B2 - Lubrication structure of reducer - Google Patents

Description

The present invention relates to a lubrication structure for a reduction gear.

Lubricating structures have been proposed for supplying lubricating oil to parts that require lubrication.
Patent Document 1 discloses a gear lubrication structure in which lubricating oil stored in an oil reservoir is pumped up and supplied by rotation of a large-diameter gear. The oil reservoir of this gear lubrication structure is divided into a small diameter gear side oil reservoir and a large diameter gear side oil reservoir by a partition wall provided with a slit-like gap. Since only a predetermined amount of the oil in the small diameter gear side oil reservoir is supplied to the large diameter gear side oil reservoir through the gap, it is possible to prevent the large diameter gear from scooping up a large amount of oil.

Patent Document 2 discloses a transfer lubrication structure in which a rib is provided on a wall of a transfer case and an oil reservoir is formed on a protruding end surface of the rib. Since the synchronizing parts of the two-wheel/four-wheel switching mechanism are immersed in the oil accumulated in the oil reservoir, the synchronizing parts can be lubricated.

Publication No. 6-12284 Japanese Patent Application Publication No. 11-22812

In recent years, in reduction gears, there has been a trend to reduce the amount of lubricating oil in the reduction gear case and set the oil level low in order to reduce the stirring resistance that occurs when the gears rotate. When the oil level is low, the amount of lubricating oil that the gears scrape up decreases, resulting in insufficient lubrication for the gears located at high locations within the reducer case. In addition, if a long period of time has passed after the vehicle has been stopped, the lubricating oil supplied to the gears located at high places will drip down due to its own weight, so when the vehicle is started again, the gears located at high places The arrival of lubricating oil to the gears is delayed, resulting in a lack of lubrication for gears located at high places.

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to improve the lubrication performance of gears arranged at high locations within a reduction gear case.

The present invention provides a differential gear case having an input shaft having an input gear, an output gear meshing with the input gear, an output shaft having a final drive gear, and a final driven gear meshing with the final drive gear; A lubrication structure for a reducer, comprising: an input shaft, a reducer case supporting the output shaft, and the differential gear case, wherein the reducer case is scratched by the final driven gear on the lower side of the input shaft. a storage rib that stores the raised lubricating oil and immerses the input gear ; and a regulating rib that restricts the lubricating oil at the bottom of the reducer case from flowing into the final driven gear side; The storage rib and the regulation rib are connected to each other .

According to the present invention, it is possible to improve the lubrication performance of gears disposed at high locations within the reduction gear case.

FIG. 1 is a front view showing the configuration of a part of a vehicle. FIG. 2 is a left side view of the reducer. FIG. 3 is a left side view of the reducer with the left case removed. FIG. 4 is a plan view of the structure inside the reducer case viewed from above. FIG. 5 is a sectional view taken along the line II shown in FIG. 2, showing the structure inside the reducer case from the front side. FIG. 6 is an enlarged sectional view of the region R portion shown in FIG. FIG. 7 is a perspective view of the light case viewed from the lower left rear side. FIG. 8 is a perspective view of the reducer case cut diagonally from the rear and left side.

In the embodiment according to the present invention, an input shaft 31 having an input gear 32, an output gear 35 meshing with the input gear 32, an output shaft 34 having a final drive gear 36, and a final drive gear meshing with the final drive gear 36. A lubrication structure for a reducer including a differential gear case 51 having a gear 52, and a reducer case 10 supporting an input shaft 31, an output shaft 34, and the differential gear case 51. A storage rib 24 is provided on the lower side of the input gear 31 to store the lubricating oil scraped up by the final driven gear 52 and immerse the input gear 32 therein. Therefore, since the lubricating oil stored in the storage rib 24 can be supplied to the input gear 32, the input gear 32 and the output gear 35 can be lubricated. Gear lubrication performance can be improved.

Hereinafter, a lubrication structure for a reduction gear according to the present invention will be explained with reference to the drawings.
FIG. 1 is a front view showing a partial configuration of a vehicle 1 including a reduction gear. In the drawings and explanations including FIG. 1, the forward moving side of the vehicle is referred to as the front side, the front side is indicated by an arrow "front", and the opposite is referred to as the rear side, with the speed reducer mounted on the vehicle as a reference. Further, the left side is indicated by an arrow "left", and the opposite is indicated as the right side. Further, the upper side is indicated by an arrow "up", and the opposite is indicated as the lower side.

As shown in FIG. 1, a motor room 2 is formed in the front of the vehicle 1, and a left side member 3L and a right side member 3R are arranged at positions left and right apart from each other with the motor room 2 in between. The left side member 3L and the right side member 3R extend in the front-rear direction, and the subframe 5 extends in the left-right direction between the left side member 3L and the right side member 3R via the left support member 4L and the right support member 4R. bridged. A power train 7 is attached to the subframe 5 in a suspended state via a left side mount member 6L, a right side mount member 6R, and a rear side mount member 6B.

The power train 7 is configured by combining a motor 8 and a reduction gear 100.
The motor 8 is a driving source and is driven by electric power supplied from a battery. The motor 8 is arranged biased to the right side in the motor room 2.
The speed reducer 100 slows down the rotation transmitted from the motor 8 and transmits it to the wheels. The speed reducer 100 is disposed biased to the left side in the motor room 2 and is coupled to the left end of the motor 8 . The reducer 100 includes a reducer case 10. The reducer case 10 is configured as a reducer case that is divided into left and right halves, including a left case 11 as a first case and a right case 12 as a second case. The left case 11 and the right case 12 are joined by overlapping each other at the mating surfaces P of flanges 11f and 12f and fastening with bolts. By joining the left case 11 and the right case 12, a space is formed inside to accommodate a deceleration mechanism 30 and a differential mechanism 50, which will be described later.

FIG. 2 is a left side view of the reducer 100, mainly showing the left case 11.
As shown in FIG. 2, the left case 11 has a front wall 11a, a rear wall 11b, a lower wall 11c, an upper wall 11d, a side wall 11e, and a flange 11f. The rear wall 11b has a curved shape that is curved along the outer diameter shape of a final driven gear 52, which will be described later. The lower wall 11c constitutes the bottom of the reducer case 10, and extends from the lower end of the front wall 11a to the lower end of the rear wall 11b. The upper wall 11d is arranged to connect the upper end of the front wall 11a and the upper end of the rear wall 11b, and is inclined downward from the front side toward the rear side. The inner surface of the upper wall 11d is smoothly continuous with the curved inner surface of the rear wall 11b. The front wall 11a is arranged to connect the front end of the upper wall 11d and the front end of the lower wall 11c. The side wall 11e is a vertical wall that connects the left ends of the front wall 11a, the rear wall 11b, the lower wall 11c, and the upper wall 11d.

FIG. 3 is a left side view of the reducer 100 with the left case 11 removed, mainly showing the insides of the light case 12 and the reducer case 10.
As shown in FIG. 3, the light case 12 has a front wall 12a, a rear wall 12b, a lower wall 12c, an upper wall 12d, a side wall 12e, and a flange 12f. The rear wall 12b has a curved shape that is curved along the outer diameter shape of a final driven gear 52, which will be described later. The lower wall 12c constitutes the bottom of the reducer case 10, and extends from the lower end of the front wall 12a to the lower end of the rear wall 12b. The upper wall 12d is arranged to connect the upper end of the front wall 12a and the upper end of the rear wall 12b, and slopes downward from the front side toward the rear side. The inner surface of the upper wall 12d is smoothly continuous with the curved inner surface of the rear wall 12b. The front wall 12a is arranged to connect the front end of the upper wall 12d and the front end of the lower wall 12c. The side wall 12e is a vertical wall that connects the right ends of the front wall 12a, the rear wall 12b, the lower wall 12c, and the upper wall 12d.

In addition, a breather chamber 80 is provided in the light case 12 by a breather plate attached to the light case 12 with bolts on the front and upper side at a corner formed by the front wall 12a, the upper wall 12d, and the side wall 12e. is formed. The breather chamber 80 is a space that separates air and oil, and communicates with the outside of the reducer case 10. When the pressure within the reducer case 10 increases, the air within the reducer case 10 is introduced into the breather chamber 80, and air and oil are separated within the breather chamber 80. The air separated from the oil is discharged from inside the breather chamber 80 to the outside of the reducer case 10. Lubricating oil is contained in the reducer case 10 up to, for example, an oil level Lv1 (double-dashed line Lv1 shown in FIG. 3) when the vehicle 1 is stopped.

The reduction gear case 10 accommodates the reduction mechanism 30, the differential mechanism 50, and the oil gutter 70.
First, the configuration of the speed reduction mechanism 30 and its surroundings will be described.
The deceleration mechanism 30 decelerates the rotation transmitted from the motor 8 and transmits it to the differential mechanism 50.
As shown in FIG. 3, the reducer 100 includes an input shaft 31 that rotates around a rotation axis S1, an output shaft 34 that rotates around a rotation axis S2, and a differential gear case 51 that rotates around a rotation axis S3. are doing. The input shaft 31, the output shaft 34, and the differential gear case 51 are arranged in parallel so that the rotation axis S1, the rotation axis S2, and the rotation axis S3 are parallel.

FIG. 4 is a plan view of the structure inside the reducer case 10 viewed from above.
As shown in FIG. 4, the speed reduction mechanism 30 includes an input shaft 31, an output shaft 34, and a differential gear case 51. The input shaft 31, the output shaft 34, and the differential gear case 51 are rotatably supported by the reducer case 10. The input shaft 31, the output shaft 34, and the differential gear case 51 have rotation axes S1, S2, and S3 parallel to each other, and extend in the left-right direction. As shown in FIGS. 3 and 4, the input shaft 31 is arranged on the front side, and the output shaft 34 is arranged on the rear side of the input shaft 31. The differential gear case 51 is arranged on the rear side of the output shaft 34. The input shaft 31 and the output shaft 34 are located approximately at the center between the lower wall 12c and the upper wall 12d. The output shaft 34 is arranged slightly above the input shaft 31. Specifically, as seen from the left side as shown in FIG. center) above the line that connects them.

The input shaft 31 is provided with an input gear 32 . The input gear 32 rotates together with the input shaft 31. The input gear 32 is a gear having a smaller diameter than the output gear 35 described later. The input gear 32 is located at a high location upwardly away from the lower wall 12c of the reducer case 10, and is placed in a position where it is difficult to immerse it in the lubricating oil stored at the bottom of the reducer case 10.

The output shaft 34 is provided with an output gear 35 and a final drive gear 36. The output gear 35 and the final drive gear 36 rotate together with the output shaft 34. The output gear 35 is a gear having a larger diameter than the input gear 32, and is always meshed with the input gear 32. The final drive gear 36 is a gear having a smaller diameter than the output gear 35, and always meshes with a final driven gear 52, which will be described later.
The speed reduction mechanism 30 includes an input gear 32 on an input shaft 31, an output gear 35 on an output shaft 34, a final drive gear 36, and a final driven gear 52 attached to a differential gear case 51. The speed reduction mechanism 30 controls the rotation transmitted from the motor 8 through the gear pair of the input gear 32 and the output gear 35, the relationship between the output gear 35 and the final drive gear 36, and the gear pair of the final drive gear 36 and the final driven gear 52. The deceleration is transmitted to the differential mechanism 50.

FIG. 5 is a sectional view taken along the line II shown in FIG. 2 and viewed from the direction of the arrow.
As shown in FIG. 5, the input shaft 31 is inserted into a hole 12g formed by penetrating the side wall 12e of the light case 12 in the left-right direction, passes through the side wall 12e, and projects to the right from the side wall 12e. A portion of the input shaft 31 that protrudes to the right from the side wall 12e of the light case 12 is connected to the motor shaft of the motor 8. Therefore, the input shaft 31 rotates together with the motor shaft of the motor 8.

The input shaft 31 is supported on the left side by a bearing 33L and on the right side by a bearing 33R. The bearing 33L is held by a bearing holding portion 15L formed on the inner surface of the side wall 11e of the left case 11. Further, the bearing 33R is held by a bearing holding portion 15R formed on the inner surface of the side wall 12e of the light case 12. Further, on the right side of the bearing holding portion 15R of the side wall 12e of the light case 12, an oil seal 40 is arranged with an annular gap G1 interposed therebetween. The oil seal 40 is press-fitted into the inner peripheral surface of the hole 12g and seals the space between the side wall 12e and the input shaft 31 to prevent lubricating oil from leaking. The oil seal 40 and the bearing 33R face each other with a gap G1 in between.

FIG. 6 is an enlarged cross-sectional view of the lowermost portion of the oil seal 40 (region R shown in FIG. 5). As shown in FIG. 6, in the oil seal 40, a seal main body 42 made of an elastic body is integrally formed with an annular reinforcing member 41 having a substantially L-shaped cross section. The seal body 42 is fixed to the inner peripheral surface of the hole 12g. The seal body 42 also includes a main lip 43 that extends to reduce its diameter toward the inside of the reducer case 10 (extends to be inclined in cross section), and a main lip 43 that reduces its diameter toward the outside of the reducer case 10. A dust lip 44 (extending obliquely in cross section) is connected thereto. Main lip 43 and dust lip 44 are examples of lips. A garter spring 45 is disposed on the outer diameter side of the main lip 43 to adjust the tightening force of the main lip 43 to the input shaft 31. The main lip 43 and the dust lip 44 are always in contact with the outer peripheral surface of the input shaft 31. The main lip 43 seals so that the lubricating oil in the reducer case 10 does not leak to the outside of the reducer case 10 through the hole 12g. The dust lip 44 seals to prevent dust from entering the reducer case 10 from outside the reducer case 10 through the hole 12g.

The output shaft 34 is supported on the left side by a bearing 37L and on the right side by a bearing 37R (see FIG. 4). The bearing 37L is held by a bearing holding portion (not shown) formed on the inner surface of the side wall 11e of the left case 11. Further, the bearing 37R is held by a bearing holding portion 18R (see FIG. 7) formed on the inner surface of the side wall 12e of the light case 12.

FIG. 7 is a perspective view of the light case 12 viewed from the lower left rear side. FIG. 7 shows the input shaft 31, output shaft 34, bearing 33R, bearing 37R, and oil seal 40 removed.
As shown in FIG. 7, a bearing holding portion 15R and a bearing holding portion 18R are formed on the inner surface of the side wall 12e. Specifically, the bearing holding portion 15R is formed inside a rib 16 that projects toward the left side in a cylindrical shape from the inner surface of the side wall 12e. Similarly, the bearing holding portion 18R is formed inside a rib 19 that projects leftward in a cylindrical shape from the inner surface of the side wall 12e. The above-mentioned hole 12g passing through the side wall 12e is located on the right side of the bearing holding portion 15R. On the other hand, the right side of the bearing holding portion 18R is not penetrated, but is closed by the side wall 12e.

The side wall 12e has a concave oil groove 17 formed by omitting the upper part of the rib 16 of the bearing holding part 15R and recessing the inner surface of the side wall 12e to the right. The oil groove 17 extends in the vertical direction, reaching the recess 21 formed in the side wall 12e at the upper part, and reaching the hole 12g at the lower part. Since the oil groove 17 reaches the hole 12g, the oil groove 17 communicates with the above-mentioned gap G1 formed between the bearing 33R and the oil seal 40. The lubricating oil is dripped from an oil delivery hole 74a (described later) of the oil gutter 70 and flows down along the oil groove 17, thereby supplying the lubricating oil to the gap G1. The lubricating oil supplied to the gap G1 lubricates the bearing 33R and also lubricates the space between the main lip 43 of the oil seal 40 and the outer peripheral surface of the input shaft 31. Moreover, the upper part of the rib 19 of the bearing holding part 18R has an oil groove 20 that penetrates in the vertical direction. Lubricating oil is dripped from an oil delivery hole 74b (described later) of the oil gutter 70 and flows down along the oil groove 20, thereby lubricating the bearing 37R held in the bearing holding part 18R.

Next, the configuration of the differential mechanism 50 and its surroundings will be explained.
The differential mechanism 50 absorbs the difference in rotation speed between the left and right wheels that occurs when the vehicle turns a curve, for example, and distributes and transmits the rotation from the speed reduction mechanism 30 to the left and right wheels. The differential mechanism 50 is arranged on the rotation axis S3 of the reduction mechanism 30 within the reduction gear case 10.
As shown in FIG. 4, the differential mechanism 50 has a differential gear case 51. That is, the differential gear case 51 is a part of the speed reduction mechanism 30 as well as a part of the differential mechanism 50. The differential gear case 51 accommodates each component of the differential mechanism 50. A final driven gear 52 is coupled to the differential gear case 51 along the outer periphery with bolts or the like. The final driven gear 52 always meshes with the final drive gear 36 of the output shaft 34.

A drive shaft 53L is inserted into the left end of the differential gear case 51, and a drive shaft 53R is inserted into the right end. The differential gear case 51 is rotatably supported by the reducer case 10 about the rotation axis S3. The rotational axis S3 of the differential gear case 51 is parallel to the rotational axis S1 of the input shaft 31 and the rotational axis S2 of the output shaft 34. Moreover, as shown in FIG. 3, the rotation axis S3 is located on the rear side of the rotation axes S1 and S2, and is located on the lower side of the rotation axes S1 and S2. The differential gear case 51 has a left end supported by a bearing 54L, and a right end supported by a bearing 54R. Note that the bearing 54L is held by the side wall 11e of the left case 11. The bearing 54R is held by the side wall 12e of the light case 12. The rotation reduced by the speed reduction mechanism 30 is transmitted from the final drive gear 36 of the output shaft 34 via the final driven gear 52, thereby rotating the differential gear case 51. When the vehicle travels straight, the differential mechanism 50 equally transmits rotation to the left and right wheels 55L, 55R via the drive shafts 53L, 53R. On the other hand, when the vehicle turns around a curve, the differential mechanism 50 transmits rotation distributed to the left and right according to the turn to the left and right wheels 55L, 55R via the drive shafts 53L, 53R.

Further, the final driven gear 52 of the reduction gear mechanism 30 is immersed in lubricating oil stored at the bottom of the reduction gear case 10. In FIG. 3, when the vehicle 1 is moving forward, the final driven gear 52 rotates counterclockwise, the output shaft 34 rotates clockwise, and the input shaft 31 rotates counterclockwise. Therefore, the lubricating oil stored at the bottom of the reducer case 10 is scraped up by the final driven gear 52 that rotates as the vehicle 1 travels, and when the vehicle 1 is moving forward, the inside of the reducer case 10 is shown in FIG. It scatters in the direction of arrow A1. That is, as the final driven gear 52 rotates, the lubricating oil flows along the curved shape of the inner surface of the rear wall 12b and the inner surface of the upper wall 12d that is continuous with the inner surface of the rear wall 12b. carried in front of.

Further, the reducer case 10 is provided with a regulating rib 13 that divides the bottom space into front and rear sections. The regulating rib 13 regulates so that a large amount of the lubricating oil stored at the front of the lubricating oil stored at the bottom does not flow into the final driven gear 52 side. In other words, the regulating rib 13 stores the lubricating oil carried forward as the final driven gear 52 rotates in the front side, and adjusts the amount of lubricating oil flowing out to the rear side (toward the final driven gear 52 side). provided. As shown in FIGS. 5 and 8, the regulating rib 13 includes a left regulating rib 14L that integrally projects from the side wall 11e of the left case 11 toward the right case 12, and a left regulating rib 14L that integrally projects from the side wall 12e of the right case 12. The right side regulating rib 14R protrudes toward the case 11.
As shown in FIG. 3, the right-side regulating rib 14R is curved along the outer diameter of the final driven gear 52 from the bottom of the reducer case 10 toward the output shaft 34 at a position on the front side of the final driven gear 52. and extend it. Note that the left side regulating rib 14L is formed at a position corresponding to the right side regulating rib 14R, and faces the right side regulating rib 14R in substantially the same shape and overlaps with the right side regulating rib 14R when the reducer case 10 is seen through from the left and right directions. It is formed like this.

FIG. 8 is a perspective view of the reducer case 10 cut obliquely with respect to the mating surface P1 of the reducer case 10, as seen from the rear and left side. As shown in FIG. 8, the end surfaces of the left side regulating rib 14L and the right side regulating rib 14R touch each other when the left case 11 and the right case 12 are combined (see also FIG. 5). Further, as shown in FIG. 3, a gap G2 is formed between the left side regulating rib 14L and the right side regulating rib 14R so that they do not touch each other even when the left case 11 and the right case 12 are combined. In other words, in the lower part of the regulating rib 13, there is a gap G2 between the end surface of the left regulating rib 14L on the light case 12 side (right end surface) and the end surface of the right regulating rib 14R on the left case 11 side (left end surface). It is formed. Therefore, since the lubricating oil on the front side of the regulating rib 13 flows into the final driven gear 52 side (rear side) only through the gap G2, the oil level of the lubricating oil on the rear side of the regulating rib 13 is low. The position can be lower than the oil level Lv1 when the vehicle is stopped. Therefore, the amount of lubricating oil that circulates around the final driven gear 52 can be reduced, and the stirring resistance when the final driven gear 52 rotates can be reduced.

Next, the configuration of the oil gutter 70 and its surroundings will be described.
The oil gutter 70 captures and stores the lubricating oil scraped up by the final driven gear 52, and supplies the stored lubricating oil to areas that require lubrication. The oil gutter 70 is located above the speed reduction mechanism 30, and is arranged at a position overlapping the speed reduction mechanism 30 when viewed from above. The oil gutter 70 is supported by the side wall 12e of the light case 12 within the reducer case 10. Specifically, as shown in FIG. 7, the oil gutter 70 is attached to the side wall 12e of the light case 12 by being coupled to the side wall 12e with a bolt 79 with the right end portion inserted into the recess 21 formed in the side wall 12e. It is attached. The oil gutter 70 is made of synthetic resin, for example.

The oil gutter 70 has a storage section 71 and a guide section 75.
As shown in FIG. 4, the storage section 71 has a bottom wall 72 and side walls 73, and is formed in a substantially box shape with an open top. The storage portion 71 captures and stores the lubricating oil scattered by being scraped up by the final driven gear 52. Oil delivery holes 74a, 74b, and 74c are formed in the bottom wall 72. The oil delivery hole 74 a is located on the right side and front side of the bottom wall 72 and above the oil groove 17 . The lubricating oil stored in the storage portion 71 is dripped from the oil delivery hole 74a toward the oil groove 17 as shown by arrow A2 in FIG. The oil delivery hole 74b is located on the right and rear side of the bottom wall 72 and above the oil groove 20. The lubricating oil stored in the storage portion 71 is dripped from the oil delivery hole 74b toward the oil groove 20 as shown by arrow A3 in FIG. 7. The oil delivery hole 74c is located on the front side of the bottom wall 72 and above the meshing portion where the input gear 32 and the output gear 35 mesh. The lubricating oil stored in the storage portion 71 is dripped into the meshing portion between the input gear 32 and the output gear 35 from the oil delivery hole 74c.

The guide portion 75 is integrally formed at the left rear end of the storage portion 71 and is formed to extend in the front-rear direction. The guide portion 75 has a bottom wall 76 and a side wall 77, and is formed with an open upper and rear end. Further, the guide section 75 causes a portion of the lubricating oil stored in the storage section 71 to drip onto the speed reduction mechanism 30 and the differential mechanism 50 from the rear end. As shown in FIG. 3, the bottom wall 76 slopes diagonally downward as the top surface goes toward the rear side. As shown in FIG. 4, the rear end of the bottom wall 76 is located above the differential gear case 51 and the final driven gear 52. That is, the rear end of the guide part 75 is arranged so as to be close to the outer periphery of the final driven gear 52, scrapes off the lubricating oil that is carried along with the final driven gear 52, receives the lubricating oil from its opening, and stores the lubricating oil. This will lead you to section 71. Therefore, a large amount of lubricating oil can be introduced into the reservoir 71 to supply the lubricating oil to parts that require lubrication, and the lubricating performance of the speed reducer 100 can be improved even with a small amount of lubricating oil. Note that the lubricating oil dripped from the rear end of the guide portion 75 is dripped onto the differential gear case 51 and the final driven gear 52. Further, an oil delivery hole 78a is formed in the bottom wall 76. The oil delivery hole 78a is located approximately at the center of the bottom wall 76 in the front-rear direction, and is located above the meshing portion between the final drive gear 36 and the final driven gear 52. A portion of the lubricating oil flowing along the guide portion 75 is dripped from the oil delivery hole 78a to the meshing portion between the final drive gear 36 and the final driven gear 52.

Next, a lubrication structure for improving the lubrication performance of the input gear 32 disposed at a high place in the speed reduction mechanism 30 configured as described above will be described.
As shown in FIG. 3, the reducer case 10 of this embodiment is provided with a storage rib 24 that stores lubricating oil below the input shaft 31 and forms an oil reservoir for immersing the input gear 32. . The storage rib 24 is formed at a height capable of storing lubricating oil at a higher liquid level than the lower part of the input gear 32. The input gear 32 is arranged such that its lower portion enters (immerses in) the lubricating oil stored in the storage rib 24. As shown in FIG. 5, the storage rib 24 includes a left storage rib 25L as a first rib that integrally projects from the side wall 11e of the left case 11 toward the light case 12, and a left storage rib 25L that is integrally protruded from the side wall 11e of the left case 11 toward the light case 12. It is composed of a right storage rib 25R as a second rib that integrally projects toward the left case 11. The end surfaces of the left side storage rib 25L and the right side storage rib 25R touch each other at the mating surface P when the left case 11 and the right case 12 are combined.

The shape of the right storage rib 25R will be described with reference to FIGS. 3 and 7.
The right storage rib 25R is formed in an arc shape below the input shaft 31 and surrounding the input shaft 31 and the input gear 32. In the right side storage rib 25R, the surface facing the input shaft 31 is recessed downward to form a recess 26 along the input shaft 31 in which lubricating oil can be stored. As shown in FIG. 7, the right storage rib 25R is integrally formed with a lower portion of the rib 16 forming the bearing holding portion 15R, and protrudes toward the left case 11.

Here, as shown in FIG. 3, the rear end portion 27a of the right storage rib 25R is located below the rotation axis S1 of the input shaft 31 and is the tip of the gear located at the lowest end of the input gear 32. (Blade tip) Located above 32t. On the other hand, the front end 27b of the right storage rib 25R is located above the rear end 27a and at approximately the same height as the rotation axis S1 of the input shaft 31. By arranging the front end 27b above the rear end 27a, the lubricating oil stored in the recess 26 is prevented from overcoming the front end 27b due to inertia and dripping from the recess 26 when the vehicle is stopped. . Note that the left side storage rib 25L is formed to overlap and face the right side storage rib 25R in substantially the same shape when the reducer case 10 is seen from the left and right directions.

The storage rib 24 configured in this manner can store lubricating oil up to the oil level Lv2 (the two-dot chain line Lv2 shown in FIG. 3) passing through the rear end portion 27a. Here, the oil level Lv2 is located above the tip 32t of the gear located at the lowest end of the input gear 32. Therefore, when lubricating oil is stored in the recess 26 of the storage rib 24, at least the tip 32t of the lowermost gear of the input gear 32 can be immersed. Then, when the input shaft 31 rotates and the input gear 32 rotates as the vehicle 1 starts running, the tip 32t of the gear to which the lubricating oil is attached reaches the meshing part between the input gear 32 and the output gear 35, and the meshing occurs. lubrication of the parts can be started early. Therefore, wear of the input gear 32 and the output gear 35 can be suppressed, and the durability of the speed reducer 100 can be improved. Further, as shown in FIG. 6, the oil level Lv2 is located above the main lip 43 located at the lowest end of the oil seal 40 that contacts the input shaft 31. That is, the oil level Lv2 of the storage rib 24 is set at a position that reaches the main lip 43 of the oil seal 40, so that a part of the main lip 43 is immersed in the lubricating oil. Therefore, when lubricating oil is stored in the recess 26, it passes through the bearing 33R and is also stored in the gap G1, making it possible to supply the lubricating oil to at least the main lip 43 located at the lowermost end of the oil seal 40. can. Therefore, lubricating oil can be supplied to the main lip 43 from the initial stage of rotation to suppress wear of the main lip 43, and the durability of the oil seal 40 can be improved.

Further, the storage rib 24 and the regulating rib 13 are connected by a connecting rib 28. As shown in FIG. 5, the connecting rib 28 includes a left connecting rib 29L that integrally projects from the side wall 11e of the left case 11 toward the right case 12, and a left side connecting rib 29L that integrally projects from the side wall 12e of the right case 12 toward the left case 11. It is composed of a protruding right side connecting rib 29R. The end surfaces of the left connecting rib 29L and the right connecting rib 29R touch each other at the mating surface P when the left case 11 and the right case 12 are combined.

The shape of the right connecting rib 29R will be described with reference to FIG. 3. The right side connecting rib 29R connects the rear end 27a of the right side storage rib 25R and the upper part of the right side regulating rib 14R in a diagonal straight line. In this way, by connecting with the right side connecting rib 29R, the strength of the right side storage rib 25R and the right side regulating rib 14R itself can be improved, and the rigidity of the speed reducer case 10 can be improved. Note that the left side connecting rib 29L has approximately the same shape as the right side connecting rib 29R when viewed through the reducer case 10 from the left and right directions, and the rear end of the left side storage rib 25L and the left side regulating rib 29R. The upper part of the rib 14L is diagonally connected in a straight line.

Next, the flow path until the lubricating oil is stored in the recess 26 of the storage rib 24 will be explained.
As described above, the lubricating oil stored at the bottom of the reducer case 10 is scraped up by the final driven gear 52, and is scattered inside the reducer case 10 along the arrow A1 direction shown in FIG. 3 when the vehicle 1 moves forward. do. The scattered lubricating oil is captured in the storage section 71 of the oil gutter 70. The lubricating oil captured by the oil gutter 70 is stored in the storage portion 71 and dripped downward from the oil delivery holes 74a, 74b, and 74c.

The lubricating oil dripped downward from the oil delivery hole 74a flows down along the oil groove 17 and is supplied to the gap G1 between the bearing 33R and the oil seal 40. The lubricating oil supplied to the gap G1 lubricates the bearing 33R and the main lip 43 of the oil seal 40, and the lubricating oil that has finished lubricating may remain in the gap G1 or pass through the bearing 33R from the gap G1 to the input gear 32 side. As the lubricating oil flows, the lubricating oil is supplied and stored in the recess 26 of the storage rib 24.
In addition, the lubricating oil dripped downward from the oil delivery hole 74c lubricates the meshing portion between the input gear 32 and the output gear 35, and the lubricating oil that has finished lubricating drips from the input gear 32, causing the lower side Lubricating oil is supplied to and stored in the recess 26 of the storage rib 24 located at . That is, the lubricating oil flowing down from the oil gutter 70 is supplied to the recess 26 of the storage rib 24. Therefore, when the vehicle stops after running, the lubricating oil that has been stored in the oil gutter 70 flows into the recess 26 of the storage rib 24, and the lubricating oil can be stored in the recess 26.
Note that among the lubricating oil scraped up and scattered by the final driven gear 52, the lubricating oil that is not captured by the oil gutter 70 and is directly sprayed onto the input shaft 31 and the input gear 32 lubricates the input shaft 31 and the input gear 32. do. The lubricating oil that has been lubricated drips down from the input shaft 31 and is supplied to and stored in the recess 26 of the storage rib 24 located on the lower side.

Here, the lubricating oil stored in the recess 26 of the storage rib 24 is taken out by the rotation of the input gear 32, but when the input gear 32 rotates, the lubricating oil continues to be scooped up by the final driven gear 52. Since the lubricating oil is supplied to the oil gutter 70, the lubricating oil can always be stored up to the oil level Lv2 when the vehicle 1 is stopped. Note that the lubricating oil that exceeds the oil level Lv2 overflows backward from the recess 26 of the storage rib 24, but the overflowing lubricating oil flows over the upper surface of the connecting rib 28 and flows to the rear of the regulating rib 13. By flowing down into the space, it is collected at the bottom of the reducer case 10.

By providing the storage rib 24 in this manner, it is possible to supply lubricating oil to the input gear 32 located at a high location to lubricate the input gear 32 located at a high location. Further, even if the vehicle is stopped for a long time, a part of the input gear 32 and a part of the main lip 43 of the oil seal 40 are inserted into the recess 26 of the storage rib 24 to maintain the oil level Lv2. It can be immersed by lubricating oil stored up to the point. Therefore, even when the vehicle is started running again after being stopped for a long time, the input gear 32 and the output gear 35 can be immediately lubricated by the part of the input gear 32 immersed in the lubricating oil scraping up the lubricating oil. I can do it. Further, the lubricating oil adhering between the input shaft 31 and a part of the main lip 43 is instantly spread between the input shaft 31 and the main lip 43 as the input shaft 31 rotates, and completely covers the main lip 43. Can be lubricated all around. Therefore, wear of the input gear 32 and oil seal 40 can be suppressed, and durability can be improved.

Furthermore, when the vehicle is stopped, some of the lubricating oil falls from the recess 26 of the storage rib 24 due to vibrations immediately after the vehicle stops, causing the lubricating oil stored in the recess 26 to fall below the oil level Lv2. In some cases, the lubricating oil stored in the storage part 71 of the oil gutter 70 continues to be dripped from the oil delivery holes 74a, 74b, and 74c even after the vehicle has stopped, until the storage part 71 is empty. Therefore, even if the lubricating oil falls from the recess 26 of the storage rib 24 immediately after the vehicle stops, the lubricant dripped from the oil delivery holes 74a and 74b will flow into the recess 26 of the storage rib 24 through the above-mentioned flow path. Since the lubricating oil is supplied, the lubricating oil can always be stored up to the oil level Lv2. In order to ensure this effect, the bottom wall 72 of the storage section 71 of the oil gutter 70 is set at a lower height than the bottom wall 76 at the front end of the guide section 75 (Fig. 3 ). This reduces the amount of lubricating oil flowing out from the guide portion 75.

As described above, according to the present embodiment, the reducer case 10 is provided with the storage rib 24 on the lower side of the input shaft 31 that stores the lubricating oil scraped up by the final driven gear 52 and immerses the input gear 32 therein. It is being Therefore, since the input gear 32 scoops up the lubricating oil stored in the storage rib 24, the input gear 32 and the output gear 35 can be lubricated, thereby improving the lubrication performance of gears arranged at high places. I can do it. Furthermore, even if the oil level of the lubricating oil stored at the bottom of the reducer case 10 is set low, the input gear 32 can be lubricated by the lubricating oil stored in the storage rib 24, so that the agitation It is possible to improve the lubrication performance of gears located at high places while reducing resistance.

In addition, in this embodiment, the storage rib 24 includes a left storage rib 25L provided on the left case 11 and a right storage rib 25R provided on the light case 12R, and the left case 11 and the right case 12R are combined. They are in contact with each other. Therefore, the rigidity of the reducer case 10, especially the rigidity in the vehicle width direction, can be improved. Further, it is possible to suppress noise caused by resonance of the reducer case 10, particularly resonance caused by deformation in the vehicle width direction.

Further, in this embodiment, the reducer case 10 is provided with a regulating rib 13 that regulates the lubricating oil at the bottom from flowing into the final driven gear 52 side, and the storage rib 24 and the regulating rib 13 are connected. ing. Specifically, the storage rib 24 and the regulating rib 13 are connected by a connecting rib 28. Therefore, the rigidity of the storage rib 24 and the regulation rib 13 can be improved more than when the storage rib 24 and the regulation rib 13 are independent. Furthermore, since the connecting ribs 28 are not limited in shape, they can be formed into an optimal shape that can suppress the resonance vibration mode of the reducer case 10. Specifically, resonance of the reducer case 10 can be suppressed by making the connecting rib 28 lie along the antinode of the vibration mode.

Further, in this embodiment, the storage rib 24 is formed integrally with the side walls 11e and 12e of the reducer case 10. Therefore, the storage rib 24 can be provided without increasing the number of parts or increasing the number of assembly steps.

In this embodiment, the reducer case 10 also has an oil gutter located above the input shaft 31 that captures the lubricating oil scraped up by the final driven gear 52 and drips it onto the input gear 32, output gear 35, etc. It has 70. Therefore, even if the lubricating oil falls from the storage rib 24 immediately after the vehicle stops, the lubricating oil dripped from the oil gutter 70 will drip down while lubricating the input gear 32. Lubricating oil can be supplied to the ribs 24.

In addition, this embodiment includes an oil seal 40 disposed between the hole 12g formed in the reducer case 10 and the input shaft 31, and the storage rib 24 stores lubricating oil and seals the oil seal. 40 main lips 43 are immersed. Therefore, even when the vehicle is started to run again after being stopped for a long time, the lubricating oil that adheres between the input shaft 31 and a part of the main lip 43 is immediately removed from the input shaft 31 by the rotation of the input shaft 31. Since it is possible to lubricate the entire circumference between the main lip 43 and the main lip 43, deterioration of the oil seal 40 can be suppressed.

Although the embodiments according to the present invention have been described above, the present invention is not limited to the above-described embodiments, and modifications can be made within the scope of the present invention.
In the embodiment described above, a case has been described in which the lubricating oil can pass through the bearing 33R from the gap G1. That is, although the case has been described in which the bearing 33R is a so-called open type, the bearing 33R is not limited to this case, and the bearing 33R may be a so-called shield type. By making the bearing 33R a shield type, the lubricating oil dripped downward from the oil delivery hole 74a of the oil gutter 70 flows down along the oil groove 17, thereby filling the gap between the bearing 33R and the oil seal 40. Remains in the entire G1. Therefore, the entire main lip 43 of the oil seal can be immersed in lubricating oil.

Further, in the above-described embodiment, the case where the drive source is the motor 8 has been described, but the drive source is not limited to this case, and the drive source may be an engine as an internal combustion engine.

10: Reduction gear case 11: Left case 12: Right case 13: Regulatory rib 24: Storage rib 28: Connection rib 30: Reduction mechanism 31: Input shaft 32: Input gear 34: Output shaft 35: Output gear 36: Final Drive gear 50: Differential mechanism 51: Differential gear case 52: Final driven gear 70: Oil gutter

Claims (6)

an input shaft having an input gear;
an output gear meshing with the input gear, and an output shaft having a final drive gear;
a differential gear case having a final driven gear that meshes with the final drive gear;
A lubrication structure for a speed reducer, comprising: a speed reducer case that supports the input shaft, the output shaft, and the differential gear case,
The reduction gear case is
a storage rib on the lower side of the input shaft that stores lubricating oil scraped up by the final driven gear and immerses the input gear;
A regulating rib is provided for regulating lubricating oil at the bottom of the reducer case from flowing into the final driven gear side,
A lubrication structure for a speed reducer , wherein the storage rib and the regulation rib are connected . an input shaft having an input gear;
an output gear meshing with the input gear, and an output shaft having a final drive gear;
a differential gear case having a final driven gear that meshes with the final drive gear;
a reduction gear case that supports the input shaft, the output shaft, and the differential gear case;
A lubrication structure for a reducer, comprising: an oil seal disposed between a hole formed in the reducer case and the input shaft,
The reduction gear case is
A storage rib is provided on the lower side of the input shaft to store lubricating oil scraped up by the final driven gear and immerse the input gear,
A lubrication structure for a speed reducer, wherein the storage rib stores lubricating oil and immerses the lip of the oil seal. an input shaft having an input gear;
an output gear meshing with the input gear, and an output shaft having a final drive gear;
a differential gear case having a final driven gear that meshes with the final drive gear;
a reduction gear case that supports the input shaft, the output shaft, and the differential gear case;
A lubrication structure for a reducer, comprising: an oil seal disposed between a hole formed in the reducer case and the input shaft,
The reduction gear case is
a storage rib on the lower side of the input shaft that stores lubricating oil scraped up by the final driven gear and immerses the input gear;
A regulating rib is provided for regulating lubricating oil at the bottom of the reducer case from flowing into the final driven gear side,
A lubrication structure for a speed reducer, wherein the storage rib is connected to the regulation rib, and stores lubricating oil to immerse the lip of the oil seal. The reduction gear case is
The first case and the second case are combined,
The storage rib is
comprising a first rib provided on the first case and a second rib provided on the second case,
According to any one of claims 1 to 3, wherein the first rib and the second rib are in contact with the first case and the second case in a coupled state. Lubrication structure of the described reducer. The storage rib is
The lubrication structure for a speed reducer according to any one of claims 2 to 4 , characterized in that the structure is formed integrally with a side wall of the speed reducer case. The reduction gear case is
According to any one of claims 2 to 5 , there is provided an oil gutter located above the input shaft that captures lubricating oil scraped up by the final driven gear and drips it onto the input gear. Lubrication structure of the described reducer.

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