WO2004076891A1

WO2004076891A1 - Differential device for vehicle

Info

Publication number: WO2004076891A1
Application number: PCT/JP2003/002279
Authority: WO
Inventors: Mitsuharu Sugeta; Kazuhiro Shigemasa
Original assignee: Ondo Corporation
Priority date: 2003-02-27
Filing date: 2003-02-27
Publication date: 2004-09-10
Also published as: JPWO2004076891A1

Abstract

A differential device (1) for a vehicle transmitting a rotational drive force from the engine of the vehicle to a drive shaft and having an increased supporting rigidity for supporting pinion shafts, comprising a pair of side gears (9), three pinions (10) meshed with the side gears (9), three pinion shafts (11) pivotally supporting the pinions (10), and an annular shaft support member (12) for supporting the inner end parts of the pinion shafts (11), wherein restricting ribs (17) for restricting three pinion shafts (11) so that the inner end parts thereof do not move in a peripheral direction are formed integrally with the inner peripheral side of the shaft support member (12), a pair of oil grooves (18) and an oil hole (19) allowing the oil grooves (18) to communicate with each other are formed in the side surface parts of the pinion shafts (11) on the side gear side, a part of the oil holes (19) is closed by the shaft support member (12), and a part thereof faces between the restriction ribs (17) in exposed state.

Description

Technical field

TECHNICAL FIELD The present invention relates to a vehicle differential device, in particular, to provide three sets of pinions and a pinion shaft in a differential gear mechanism, to increase support rigidity for supporting these pinions, and to improve lubrication performance for lubricating a pinion-pinion shaft. The present invention relates to a vehicle differential.

Akira Background technology

A vehicle differential generally includes a differential gear mechanism including a pair of left and right side gears, a plurality of pinions, and a pinion shaft that pivotally supports the pinions, and a gear case that houses the differential gear mechanism. When the vehicle travels straight, the rotational driving force from the engine is transmitted to the gear case of the vehicle differential, and the gear case and a plurality of pinions rotate about the drive shaft axis. It is transmitted from the gear case and the multiple pinions to a pair of side gears, and transmitted from the pair of side gears to a pair of drive shafts. When the vehicle is turning, the left and right drive shafts can rotate at different rotational speeds through the rotation of multiple pinions.

Conventionally, as the vehicular differential, a two-pinion type differential having two pinions and a four-pinion type differential having four pinions have been put into practical use. For example, Japanese Patent Application Laid-Open No. 2002-122222 discloses a two-pinion type vehicle differential. In the differential gear mechanism of this differential device, two pinions are pivotally supported by one pinion shaft, and both ends of the pinion shaft are supported by the gear case. Although the rigidity can be secured, the load due to the driving force of each pinion is large, so the pinions are easily worn and it is difficult to increase the durability.

On the other hand, Japanese Patent Application Laid-Open No. 2002-3656430 discloses a 4-pinion type vehicle differential. In the differential gear mechanism of this differential, A fixed intermediate ring is provided, and the outer peripheral ends of four pinion shafts are mounted on the intermediate ring. The intermediate ring supports the four pinion shafts in a cantilever manner so that they cannot rotate.

Next, the conventional technology and its problems will be described.

In the vehicle differential disclosed in Japanese Patent Application Laid-Open No. 2002-3656430, since four pinion shaft forces are supported in a cantilever manner by the intermediate ring, the support rigidity for supporting each pinion shaft is provided. Is low. As a result, the pinion shaft tilts or deviates from the expected position together with the pinion. As a result, the engagement between the four pinions and the two side gears deteriorates, and the wear of those pinions and the side gears progresses, so that the life is shortened and vibration noise is easily generated.

In addition, the lubricating oil that lubricates the sliding part where the pinion and the gear case come into contact flows from the center to the outer periphery along the pinion shaft due to centrifugal force, but due to the uneven wear of the pinion shaft, the lubricating oil flows. It is hindered and lubricity is reduced. Also, in this 4-pinion type vehicle differential, the number of parts is large, the structure is complicated, and the manufacturing cost is high.

In view of this, the applicant of the present application has proposed a three-pinion type vehicle differential device having three pinions in an earlier international application (PCT / JPO2Z07935). In this differential device, an annular shaft support member for supporting the 內 end portions of the three pinion shafts is provided at the center of the differential gear mechanism. If the thickness of the shaft support member in the radial direction is increased, the flow of the lubricating oil flowing into the center of the differential gear mechanism tends to decrease. Conversely, if the thickness of the shaft support member in the radial direction is reduced, it is difficult to increase the support rigidity for supporting the inner end of the pion shaft.

An object of the present invention is to provide a three-pinion type vehicle differential. Another object of the present invention is to provide a differential for a vehicle in which support rigidity for supporting a pinion shaft is increased. Another object of the present invention is to provide a differential for a vehicle with improved lubrication performance for lubricating the periphery of a pinion. Other objects of the present invention will be apparent from the description of the effects of the present invention and the description of the embodiments. Disclosure of the invention

The vehicle differential according to the present invention is a vehicle differential that transmits a rotational driving force from a vehicle engine to a driving axle. The vehicle differential includes a pair of side gears, three pinions corresponding to the side gears, and the pinions. A differential gear mechanism comprising three pinion shafts each pivotally supporting the pinion shaft, and an annular shaft support member for supporting an inner end of the pinion shaft, wherein the shaft support member comprises three pinion shafts. Three shaft holes respectively supporting the inner ends of the shafts; and three regulating ribs integrally formed on the inner peripheral side of the shaft supporting member, wherein the inner ends of the three pinion shafts extend in the circumferential direction. It is characterized by having three regulating ribs for regulating movement.

Since three regulating ribs are provided on the shaft support member of the differential gear mechanism, the support rigidity that regulates the inner end of the pinion shaft so that it does not move in the circumferential direction is increased, and the pinion shaft is inclined from the intended position. As a result, the pinion and side gear mesh well, reducing the wear on the differential gear mechanism, increasing durability and improving vibration noise. As described above, the three regulating ribs can increase the support rigidity, so that the radial thickness of the annular shaft support member can be reduced, and the inflow of lubricating oil into the shaft support member can be promoted. However, the flow of the lubricating oil from the inside of the shaft support member to the outer peripheral side along the pinion shaft can be promoted, and the lubrication performance can be improved.

Since this vehicle differential is a three-pinion type vehicle differential, the number of parts is small and the load due to the driving force of each pinion does not become excessive.

Next, preferred configurations and configurations relating to the configuration of the present invention will be described.

a) The regulating rib is formed at a position on the inner peripheral side of the shaft support member corresponding to a position between the shaft holes and at a position retreated toward the center from both axial ends of the shaft support member. .

b) A pair of oil grooves are provided in a portion of the outer peripheral portion of the pinion shaft on a pair of side gears over substantially the entire length in the length direction of the pinion shaft, and the pair of oil grooves are provided at an inner end of the pinion shaft. An oil hole for communicating the groove is provided.

c) The oil hole is formed parallel to the axis of the shaft support member.

d) The oil hole is provided at a position where a part thereof is closed by the shaft support member. e) Part of the oil hole formed at the inner end of the pinion shaft is exposed between a pair of regulating ribs. BRIEF DESCRIPTION OF THE FIGURES

1 is a cross-sectional view of a vehicle differential according to an embodiment of the present invention, FIG. 2 is a cross-sectional view taken along the line Π-ΙΙ of FIG. 1, FIG. 3 is a perspective view of a shaft support member, 4 is a perspective view of the gear case, FIG. 5 is a side view of the gear case as viewed from the direction of arrow V in FIG. 4, and FIG. 6 is a bottom view of the gear case as viewed from the direction of arrow VI of FIG. BEST MODE FOR CARRYING OUT THE INVENTION

Next, the best mode for carrying out the present invention will be described.

This embodiment is an example of a case where the present invention is applied to a vehicle differential that transmits rotational driving force from an engine to a drive shaft in a front-wheel drive type vehicle. As shown in FIGS. 1 and 2, the vehicle differential 1 includes a differential gear mechanism 2, an integrated gear case 3 that houses the differential gear mechanism 2, and a plurality of flanges 4 of the gear case 3. A ring gear 6 fixed by bolts 5 of the vehicle, and a mission case 7 that accommodates all components of the vehicle differential 1 together with lubricating oil. The ring gear 6 is formed separately from the flange 4, and the ring gear 6 is fixed to the flange 4 by a plurality of bolts 5, and the rotational driving force of the engine is input to the ring gear 6.

The differential gear mechanism 2 includes a pair of left and right side gears 9 that are respectively non-rotatably connected to ends of a pair of left and right drive shafts 8, and three pinions 10 coupled to the side gears 9. Three pinion shafts 11 that pivotally support these pinions 10, annular shaft support members 12 that support the inner ends of the three pinion shafts 11, respectively, mounted between the gear case 3 and the side gear 9 And a thrust washer 13 b mounted between the pin 10 and the gear case 3.

The three pinions 10 are arranged such that the phase angle between their axes is 120 degrees, and the pinion shaft 11 is formed in a shaft hole 30 formed parallel to the axis of the pinion 10. Letter The pinion 10 is rotatably supported by a pinion shaft 11.

As shown in FIGS. 1 to 3, the shaft support member 12 is formed in an annular shape having a short length in the axial direction. The shaft support member 12 includes an annular annular portion 12a and three pinion shafts. 3 Three shaft holes 16 supporting the inner ends of 1 and three restricting ribs 17 integrally formed on the inner peripheral side of the shaft support member 12. It has three restricting ribs 17 for restricting the inner end of 11 from moving in the circumferential direction. The restricting rib 17 is formed at a position corresponding to between the shaft hole 16 and the shaft hole 16 in the shaft support member 12. The restricting ribs 17 are formed at both ends in the axial direction of the shaft support member 12. It is formed at a position retreated to the center from the part. The thickness of the regulating rib 17 in the axial direction is about 2/3 of the axial length of the shaft supporting member 12, and the regulating rib 17 is formed in the longitudinal direction of the shaft supporting member 12. It is formed symmetrically with respect to the center in FIG.

A pin hole 15a is formed at the outer end of each pinion shaft 11, and the outer end of the pinion shaft 11 is fixed to the gear case 3 through a spring pin 15 through the pin hole 15. ing. The inner end of each pinion shaft 11 is supported by penetrating through a shaft hole 16 of the shaft support member 12. The inner end of each pinion shaft 11 is supported by a pair of regulating ribs 17 on both sides thereof so as not to move in the circumferential direction of the shaft support member 12.

As a result, the rigidity of supporting the pinion shaft 11 on the shaft support member 12 is increased, and the pinion shaft 11 and the pinion 10 maintain their desired positions, and the pinion 10 and the side gear 9 engage with each other. The pinion 10 and the pinion shaft 11 and the side gear 9 are less likely to be unevenly worn, the durability of the differential gear mechanism 2 is improved, and the vibration noise generated from the differential gear mechanism 2 is also reduced.

Since the pinion shaft 10 does not wear unevenly on the pinion shaft 11, the oil groove 18 on the pinion shaft 11 is not blocked and the pinion shaft 1 from the inside of the shaft support member 1 2 by centrifugal force. The flow of the lubricating oil flowing along the 1 to the outer end of the pinion shaft 11 (that is, toward the gear case 3) is promoted.

In the outer peripheral portion of the pinion shaft 11, a pair of oil grooves 18 is formed in a portion on the side of the pair of side gears 9 over substantially the entire length in the length direction of the pinion shaft 11. The inner end is provided with an oil hole 19 for communicating the pair of oil grooves 18. You. The oil groove 18 has a flat portion 18 a formed by chamfering the side surface of the cylindrical pinion shaft 11, and a groove portion 18 b formed on the flat portion 18 a. The lubricating oil flowing from the inner end of the pinion 18 flows to the outer end along the oil groove 18 by centrifugal force, and is supplied to the outer surface of the pinion 10. The oil hole 19 is formed in parallel with the axis of the shaft support member 12, a portion of which is closed by the shaft support member 12, and a portion of which is exposed between the pair of regulating ribs 17. It is provided at a position where it faces. By providing the oil hole 19 in this way, for example, when the lubricating oil flows from left to right in FIG. 1, part of the lubricating oil flowing into the left end of the oil hole 19 is The direction is changed to the right oil groove 18 by the shaft support member 12 that blocks a part of the right end of 19, and flows to the right oil groove 18. Therefore, the outer surface of the pinion 10 (gear case 3 The amount of lubricating oil supplied to the surface increases. The opposite is true if the lubricant flows from left to right in FIG.

As shown in FIGS. 4 to 6, the gear case 3 includes a case body 14, a flange portion 4, and three openings 20, 21, 22 for incorporating the side gear 9 and the pinion 10. Have. Of the peripheral wall 14 a of the case body 14, the strength peripheral wall 14 b located between the three openings 20, 21, 22 supports the outer ends of the three pinion shafts 11, respectively. The three shaft holes 23 are formed at intervals of 120 degrees in the circumferential direction.

The three openings 20, 21, and 22 are substantially D-shaped openings with the flange 4 side straight when viewed from the side, and the first openings 20, 21 for incorporating the pinion 10. A second opening 22 having a special shape different from the first openings 20 and 21 and capable of being incorporated with the side gear 9 in an inclined posture. In order to facilitate the incorporation of the side gear 9, a recess 22 a is formed in the flange 4 so as to be continuous with the second opening 22.

Next, a method of incorporating the differential gear mechanism 2 into the gear case 3 will be briefly described. First, the left and right side gears 9 are tilted about 30 degrees together with the respective thrust washers 13a, introduced into the gear case 3 from the second opening 22, and inserted into the position shown in FIG. Next, the two pinions 10 from the two first openings 20 and 21 are assembled together with the respective thrust washers 13b, and the two side gears 9 and two After rotating the pinion 10 by 120 degrees, the shaft support member 12 is assembled from one of the first openings 20 and then the two pinions 10 into which the remaining pinions 10 have been previously assembled. From one of the first openings 20 so as to have a phase angle of 120 degrees. Next, the side gear 9, the pinion 10 and the shaft support member 12 are rotated 60 degrees in the gear case 3, and the shaft hole 30 of each pinion 10, the shaft hole 23 of the gear case 3, and the shaft support Align the shaft hole 16 of the member 12 with the pinhole shaft 11 from the outside of the gear case 3 through the matched shaft hole 30, 23, 16, and connect the pinion shaft 11 with a spring pin. Fix to gear case 3 with 1 5.

As shown in FIG. 1, the transmission case 7 can be divided into a transmission case body on the left side and a housing on the right side near the ring gear 6, and has a structure fixed with a plurality of bolts. The transmission case 7 surrounds the outer peripheral sides of the gear case 3 that houses the differential gear mechanism 2 and the ring gear 6 and stores lubricating oil. A bearing 26a is installed between the ring part 25a at the left end of the transmission case 7 and the case body 14, and an oil seal 27a is installed between the ring part 25a and the drive shaft 8. Have been. A bearing 26 b is mounted between the ring 25 b at the right end of the case 7 and the case body 14, and an oil seal 27 is provided between the ring 25 b and the drive shaft 8. b is attached.

Next, the operation of the vehicle differential device 1 described above will be described.

When the rotational driving force from the vehicle engine is input to the ring gear 6, the rotational driving causes the gear case 3 to rotate around the axis of the drive shaft 8. When the vehicle travels straight, the pinion 10 pivotally supported by the gear case 3 via the pinion shaft 11 by the rotation of the gear case 3 publicly moves about the axis of the drive shaft 8, The left and right side gears 9 and the drive shaft 8, which are combined with the pinion 10, are driven to rotate. When the vehicle turns, the pinion 10 revolves around the pinion shaft 11 while revolving, allowing differential rotation of the left and right wheels. According to the vehicle differential device 1 described above, the following effects can be obtained.

This vehicle differential 1 is a three-pillion type differential having three pinions 10. Therefore, the number of parts is smaller than that of the 4-pinion type differential device, and the structure is simplified. Further, in the vehicle differential 1, the load on each pinion 10 is smaller than that of the 2-pinion type differential, and the durability of the pinion 10 is higher.

Three regulating ribs 17 are integrally formed on the inner peripheral side of the shaft support member 12 of the differential gear mechanism 2 to prevent the inner end of the pinion shaft 11 from moving in the circumferential direction. The support rigidity for supporting the shaft 11 is remarkably improved, the three pinions 10 and a pair of side gears 9 are well engaged, and the side gears 9 and the pinions 10 and the pinion shafts 11 are biased. Wear is less likely to occur, their durability is improved, and vibration noise in the differential gear mechanism 2 is also reduced.

Since the three supporting ribs 17 can increase the circumferential rigidity for supporting the three pinion shafts 11, the thickness of the annular portion 12 a of the shaft supporting member 12 is reduced, and the shaft supporting member 1 is reduced. The inflow of lubricating oil into the inside of the shaft 2 is promoted, and the weight of the shaft support member 12 can be reduced. A pair of oil grooves 18 and an oil hole 19 communicating the oil grooves 18 are formed in the pinion shaft 11, and a part of the oil hole 19 is closed by a shaft support member 12. Since the remaining part of 19 is exposed, the inflow of lubricating oil is promoted and lubrication performance can be improved.

In other words, the lubricating oil flows outward from the center side along the pinion shaft 11 due to the centrifugal force. However, when the lubricating oil flows from left to right in FIG. A part of the lubricating oil that has flowed into the left end is turned by the shaft support member 12 toward the right oil groove 18 at the right end of the oil hole 19 and flows into the right oil groove 18, so that the pinion The amount of lubricating oil supplied to the outer surface of the cylinder increases. When the lubricating oil flows from the right to the left in FIG. 1, the flow is opposite to the above. Moreover, the regulating rib 17 also has a function of guiding the lubricating oil toward the oil hole 19.

The present invention is not limited to the embodiments described above, and those skilled in the art can implement various modifications to the above embodiments without departing from the spirit of the present invention. The present invention also includes those modifications.

The shape of the regulating rib 17 and the shapes of the oil groove 18 and the oil hole 19 formed in the pinion shaft 11 are merely examples, and are not limited to the shapes shown in the drawings. The vehicle differential 1 is an example of a three-pin type differential for a front wheel drive vehicle, but the present invention is similarly applicable to a differential for a rear wheel drive vehicle. Note that the ring gear of the differential unit of the rear wheel drive vehicle is not a spur gear but a helical gear.

Claims

The scope of the claims

1. In a vehicle differential that transmits the rotational driving force from the vehicle engine to the drive axle,

A differential comprising a pair of side gears, three pinions engaged with the side gears, three pinion shafts each pivotally supporting the pinions, and an annular shaft support member supporting the inner ends of the pinion shafts. A dynamic gear mechanism is provided,

The shaft support member includes three shaft holes that respectively support inner end portions of three pinion shafts, and three regulating ribs integrally formed on an inner peripheral side of the shaft support member, and three pinions. It has three regulating ribs that regulate the inner end of the shaft from moving in the circumferential direction.

A differential device for a vehicle, comprising:

2. The regulating rib is formed at a position corresponding to between the shaft holes on the inner peripheral side of the shaft support member and at a position retreated toward the center from both axial ends of the shaft support member. 2. The vehicle differential according to claim 1, wherein

3. A pair of oil grooves are provided in a portion of the outer peripheral portion of the pinion shaft on a pair of side gears over substantially the entire length in the length direction of the pinion shaft. 2. The vehicle differential according to claim 1, further comprising an oil hole communicating the oil groove.

4. The vehicle differential according to claim 3, wherein the oil hole is formed in parallel with an axis of the shaft support member.

5. The vehicle differential according to claim 3, wherein the oil hole is provided at a position where a part of the oil hole is closed by a shaft support member.

6. The vehicle differential according to claim 4, wherein a part of an oil hole formed at an inner end of the pinion shaft is exposed between a pair of regulating ribs. Dress