TRANSFER STRUCTURE FOR VEHICLE
20190032769 ยท 2019-01-31
Inventors
- Yuzo OHKAWA (Hiroshima-shi, JP)
- Yoshihito Noguchi (Hiroshima-shi, JP)
- Wataru Harazawa (Hiroshima-shi, JP)
Cpc classification
F16H57/0447
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F16H57/0453
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F16H2057/02043
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
B60K17/3467
PERFORMING OPERATIONS; TRANSPORTING
F16H57/0423
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
B60K23/0808
PERFORMING OPERATIONS; TRANSPORTING
F16H57/0457
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
B60K17/35
PERFORMING OPERATIONS; TRANSPORTING
B60K2023/0825
PERFORMING OPERATIONS; TRANSPORTING
International classification
Abstract
A transfer device includes a drive gear, a driven gear arranged at a lower position than the drive gear, and a housing space storing gears, wherein a lubricating oil is reserved in a lower part of the housing space, wherein first and second lubricating oil reservoir spaces reserving the lubricating oil respectively adjacent to the housing space are partitioned from the housing space by first and second partition walls, wherein communication holes communicating in a state of restricting the flow to the housing space are respectively provided on the first and the second partition walls, wherein the first partition wall is provided at a lower position than a predetermined oil level and the second partition wall is provided at a higher position than the predetermined oil level.
Claims
1. A transfer structure for a vehicle, comprising: a first rotation member arranged at a high position corresponding to a higher one of a drive side power transmission member and a driven side power transmission member; a power transmission mechanism having a second rotation member arranged at a lower position than the first rotation member; a case for supporting the first rotation member and the second rotation member; a housing space for storing the power transmission mechanism in the case, wherein a lubricating oil is reserved in a lower part of the housing space so as to submerge a lower part of the second rotation member, wherein the lubricating oil is lapped up by the second rotation member and supplied to the first rotation member, wherein a first lubricating oil reservoir space and a second lubricating oil reservoir space for reserving the lubricating oil respectively adjacent to the housing space are provided in the case, wherein a first partition wall partitions between the housing space and the first lubricating oil reservoir space, wherein a second partition wall partitions between the housing space and the second lubricating oil reservoir space, wherein a first communication oil passage for communicating in a state of restricting the flow of the lubricating oil between the housing space and the first lubricating oil reservoir space is provided on the first partition wall, wherein a second communication oil passage for communicating in a state of restricting the flow of the lubricating oil between the housing space and the second lubricating oil reservoir space is provided on the second partition wall, and, wherein the first partition wall is provided at a lower position than a predetermined oil level set as an oil level when the vehicle stops, and the second partition wall is provided at a higher position than the predetermined oil level.
2. The transfer structure for a vehicle according to claim 1, wherein the first lubricating oil reservoir space is provided at a position overlapped with the housing space as viewed along a direction orthogonal to an axial direction of the first rotation member.
3. The transfer structure for a vehicle according to claim 1, wherein the second lubricating oil reservoir space is provided at a position overlapped with the housing space as viewed along an axial direction of the first rotation member.
4. The transfer structure for a vehicle according to claim 1, wherein the first and second communication oil passages of the first partition wall and the second partition wall are configured by respective communication holes.
5. The transfer structure for a vehicle according to claim 1, wherein the first rotation member and the second rotation member are helical gears, wherein a first lubricating oil reservoir space is provided on the front side in a rotating direction of the second rotation member, wherein the first partition wall is provided along a tooth surface of the second rotation member, and wherein the first communication oil passage of the first lubricating oil reservoir space is provided on the front side in the rotating direction of the tooth surface of the second rotation member on the first partition wall.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0030]
[0031]
[0032]
[0033]
[0034]
[0035]
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0036] Hereinafter, details of a transfer device of a vehicle according to an embodiment of the present invention will be described.
[0037]
[0038] A transfer device 10 is provided on a rear side of the transmission 3, and an output shaft for the rear wheels 11, which extends to the vehicle rear side and outputs the driving force output from the transmission to the rear wheels, and a front wheel output shaft 12, which is arranged in parallel to the rear wheel output shaft 11 and outputs the driving force to the front wheels, are provided in the transfer device 10.
[0039] A coupling 13, a drive gear 21 as a first gear, which is arranged on a front side relative to the vehicle body of the coupling 13 and also transmits the driving force drawn from the coupling 13 to the front wheel output shaft 12, and a damper device 14, which is arranged between the coupling 13 and the drive gear 21, are provided on the rear wheel output shaft 11.
[0040] Moreover, a driven gear 22 as a second gear, which is engaged with the drive gear 21 is provided on the front wheel output shaft 12, and the driving force for front wheels drawn by the coupling 13 is transmitted to the front wheel output shaft 12 via the drive gear 21 and the driven gear 22.
[0041] Further, the drive gear 21 and the driven gear 22 are helical gears, and collectively form a power transmission mechanism 20.
[0042] The front wheel output shaft 12 is connected to a front wheel propeller shaft 40 extending to the front side of the vehicle body via a universal joint 30. The front wheel propeller shaft 40 is connected to an input shaft 61 of a front wheel differential gear 60 via the universal joint 50 and the input shaft 61 is connected to the axles 62, 62 that are respectively connected to the right and left front wheels.
[0043] Accordingly, the driving force drawn by the coupling 13 is transmitted to the front wheel output shaft 12 via the drive gear 21 and the driven gear 22 and transmitted from the front wheel output shaft 12 to the front wheels via the front wheel propeller shaft 40 and the differential gear for front wheels 60. For the four-wheel drive vehicle 1, the coupling 13 can change the torque distribution between the front wheels and the rear wheels within a range of front wheels:rear wheels of 0:100 to 50:50. Moreover, the operations of the coupling 13 are controlled by a control unit (not shown) that includes a processor and associated non-volatile memory storing control programs that are executed by the processor to achieve the functions described herein.
[0044] Next, with reference to
[0045] A case 70 of the transfer device 10, as shown in
[0046] The rear wheel output shaft 11, which is connected to an input shaft 3a from the transmission 3, and the front wheel output shaft 12, which is provided in parallel to the rear wheel output shaft 11, are rotatably supported in the transfer case 70. A housing space Z1, which stores the drive gear 21 forming the power transmission mechanism 20 and the driven gear 22, is formed between the main body 71 and the cover 72 of the transfer case 70.
[0047] Moreover, the driven gear 22 of the power transmission mechanism 20 is provided on the rear wheel output shaft 11 in a hollow shaft form, the driven gear 22 is provided on the front wheel output shaft 12 in a hollow shaft form, and the drive gear 21 and the driven gear 22 are arranged to be engaged with each other.
[0048] Teeth 21a are formed with slanted teeth profiles on the outer peripheral surface of the drive gear 21, and a cylindrically shaped front side cylindrical part 21b and a cylindrically shaped rear side cylindrical part 21c, which integrally extend from the inner peripheral side of the teeth 21a to the vehicle body front side and the vehicle body rear side respectively, are arranged on the drive gear 21. The drive gear 21 is rotatably supported in the transfer case 70 via bearings 81 and 82 provided on the outer peripheral side of the front side cylindrical part 21b and the rear side cylindrical part 21c.
[0049] An outer race 81a of the bearing 81 of the vehicle body front side, among the bearings 81 and 82, is press fitted into a press-fit part 73 consisting of a circular concavity provided on the cover 72 of the transfer case 70. On the other hand, an outer race 82a of the bearing 82 of the vehicle body rear side is press fitted into a press-fit part 74 consisting of a circular concavity provided on the main body 71 of the transfer case 70.
[0050] Moreover, a plate member 85, which is in contact with the outer race 81a of the bearing 81 and also extends from the inner peripheral surface of the press-fit part 73 of the cover 72 to the outer peripheral surface of the rear wheel output shaft 11 of the transfer device 10, is provided on an end part of the vehicle body front side of the bearing 81, and the axial direction of the bearing 81 is positionally fixed in this manner.
[0051] Teeth 22a are formed with slanted teeth profiles on the outer peripheral surface, and a longitudinal surface part 22b extending to inner peripheral side of the teeth 22a and extending from the end part of the vehicle body rear side to the inner peripheral side, and a cylindrically shaped front side cylindrical part 22c and a cylindrically shaped rear side cylindrical part 22d extending from the end part of the inner peripheral side of the longitudinal surface part 22b to the vehicle body front side and the vehicle body rear side respectively, are arranged on the driven gear 22. The driven gear 22 is rotatably supported in the transfer case 70 via bearings 83 and 84 provided on the inner peripheral side of teeth 22a and the outer peripheral side of the rear side cylindrical part 22d.
[0052] The bearing 83 of the vehicle body front side, among the bearings 83 and 84 of the driven gear 22, is arranged below an engaging part X between the drive gear 21 and the driven gear 22 viewing the radial direction of the driven gear 22, and also an inner race 83a of the bearings 83 of the vehicle body front side is press fitted into a press-fit part 75 consisting of a circular concavity provided on the cover 72 of the transfer case 70. On the other hand, an outer race 84a of the bearing 84 of the vehicle body rear side is press fitted into the press-fit part 76 consisting of a circular concavity provided on the main body 71 of the transfer case 70.
[0053] Moreover, lubricating oil for lubricating the power transmission mechanism 20 is reserved in a lower part of the housing space Z1 so as to submerge a lower part of the driven gear 22, the lower part of the housing space Z1 thus functioning as an oil storage part.
[0054] The front wheel output shaft 12 is spline-fitted and connected to the inner peripheral surface of the front side and the rear side cylindrical parts 22c and 22d of the driven gear 22. The front wheel output shaft 12 is connected to a front wheel propeller shaft 40 via the universal joint 30 and an outside joint member 31 of the universal joint 30 is integrally formed with the vehicle body front side of the front wheel output shaft 12.
[0055] The universal joint 30 includes the outside joint member 31 that is integrally formed to the front wheel output shaft 12, an inside joint member 32 that is coupled to the front wheel propeller shaft 40, one or more balls 33 that are interposed between the outside joint member 31 and the inside joint member 32 and transmit power between the outside joint member 31 and the inside joint member 32, and a cage 34 that is arranged between the inner peripheral surface of the outside joint member 31 and the outer peripheral surface of the inside joint member 32 and retains the balls 33, and can transmit power between the front wheel output shaft 12 and the front wheel propeller shaft 40.
[0056] Moreover, for the transfer device 10, a plurality of seal members 71a, 72a, and 72b are arranged in the transfer case 70, and the lubricating oil in the transfer case 70 is prevented from leaking outside. Specifically, the seal member 72a is arranged between the cover 72 of the transfer case 70 and the rear wheel output shaft 11, the seal member 72b is arranged between the cover 72 of the transfer case 70 and the front side cylindrical part 22c of the driven gear 22, and the seal member 71a is arranged between the main body 71 of the transfer case 70 and the power transmission member 14a extending from the damper device 14 provided on the rear wheel output shaft 11.
[0057] Moreover, the lubricating oil to lubricate the power transmission mechanism 20 and the bearings 81, 82, 83, and 84 and the like is reserved in the transfer device 10.
[0058] Hereinafter, details about a lubricating oil reservoir space, in which the lubricating oil is reserved, will be described with reference to
[0059]
[0060] The first lubricating oil reservoir space Z2 is formed by partitioning between the lower part of the transfer case 70 and the housing space Z1 by the first partition wall W1.
[0061] Specifically, as shown in
[0062] Further, as shown in
[0063] Furthermore, a notch 71e is arranged in the lower part of the end face 71d of the partition wall 71c of the main body 71, and a communication hole 71e of the first partition wall W1 (71c and 72c) partitioning between the housing space Z1 and the first lubricating oil reservoir space Z2 is formed by contacting the notch 71e with the end face 72 d of the partition wall 72c of the cover 72. Moreover, the fluidic communication state for flow of lubricating oil between the housing space Z1 and the first lubricating oil reservoir space Z2 is restricted by the communication hole 71e.
[0064] The second lubricating oil reservoir space Z3 is formed by partitioning the lower part of the main body 71 of the transfer case 70 and the housing space Z1 with an oil path 91 as the second partition wall W2.
[0065] Specifically, as shown in
[0066] The basic surface 92 of the oil path 91 is fixed to a mounting part provided on the inner peripheral part of the main body 71 of the transfer case 70 with a plurality of bolts 92a.
[0067] Moreover, as shown in
[0068] Further, a seal member 92b is arranged on the outer peripheral part of the basic surface 92 of the oil path 91, and the oil path 91 and the inner peripheral surface of the main body 71 of the transfer case 70 are sealed by the seal member 92b. Thus, the basic surface 92 of the oil path 91 functions to partition between the housing space Z1 provided on the vehicle body front side across the basic surface 92 and the second lubricating oil reservoir space Z3 surrounded by the basic surface 72 and the inner peripheral part of the main body 71 of the transfer case 70 of the vehicle body rear side. Moreover, the housing space Z1 and the second lubricating oil reservoir space Z3 are partitioned to be in a fluidic communication state in which the communication hole 96 in the oil path 91 restricts flow therebetween.
[0069] As shown in
[0070] The housing space Z1 fluidically communicates with the second lubricating oil reservoir space Z3 at the notch 95 of the oil path 91. Therefore, the lubricating oil can be reserved up to the level of the end part 95a of the lower part of the notch 95. Moreover, the second lubricating oil reservoir space Z3 and the housing space Z1 are partitioned to be in a fluidic communication state such that the communication hole 96 of the oil path 91 restricts the flow therebetween.
[0071] As shown in
[0072] Then an upper end W11 of the first partition wall W1 is set to the lower position than the oil level L when the vehicle stops and is submerged in the lubricating oil. On the other hand, the end part 95a of the lower side of the notch 95 forming the second partition wall W2 is set to a higher position than the oil level L when the vehicle stops and the end part 95a of the lower side of the notch 95 protrudes above the liquid level of the lubricating oil.
[0073] Incidentally, for the lubrication of the transfer device 10 according to the present embodiment, the lubricating oil reserved in the housing space Z1 is lapped up and scattered by the toothed surface of the driven gear 22 and supplied to the drive gear 21 side. Moreover, as shown in
[0074] The lubricating oil of the tooth surface 22a of the driven gear 22 flows along a direction indicated by arrow R2 along the inclination of the toothed surface 22a of the driven gear 22 in a static condition, however, since the driven gear 22 is rotating in the direction of arrow R1, the lubricating oil is easily scattered to the vehicle body rear side but is hardly scattered to the vehicle body front side.
[0075] In order to eliminate undesirable deviations in the supply of the lubricating oil as described above, for the power transmission mechanism 20, a guide part 94 for guiding the lubricating oil to the vehicle body front side is provided on the oil path 91 to supply the lubricating oil to the vehicle body front side.
[0076] As shown in
[0077] Moreover, as shown in
[0078] With reference to
[0079] In the transfer device 10 configured like this, the driven gear 22, which is enmeshed with the drive gear 21, is rotated at the time of driving, and the lubricating oil reserved in the housing space Z1 is lapped up by the driven gear 22, so that the drive gear 21 side is lubricated.
[0080] As described above, when the driven gear 22 stops, the lubricating oil of the housing space Z1, the first lubricating oil reservoir space Z2, and the second lubricating oil reservoir space Z3 becomes the same oil level L via the communication holes 71e and 96 provided in the first and the second partition walls W1 and W2, by flowing under the effect of gravity to an equilibrium state from positions higher than the upper end W11 of the first partition wall W1 (with reference to
[0081] Moreover, at the time of low speed rotation of the driven gear 22, as shown in
[0082] On the other hand, at the time of high speed rotation of the second rotation member, as shown in
[0083] As a result, since the lubricating oil flowing to the housing space Z1 is supplied only by the communication holes 71e and 96 of the first and the second partition wall W1 and W2, the oil level L12 in the housing space Z1 can be reduced and the stirring resistance during high speed rotation of the driven gear 22 can be reduced.
[0084] Moreover, when shifting from high speed rotation to low speed rotation of the second rotation member, as shown in
[0085] With such a configuration, an oil level suitable for both times of low speed rotation and of high speed rotation can be obtained, and improvements can be achieved that address lubrication shortages at times of low speed rotation and reductions of the stirring resistance at times of high speed rotation.
[0086] Moreover, in the present embodiment, since the first lubricating oil reservoir space Z2 is provided at a position overlapped with the housing space Z1 as viewed along a direction orthogonal to an axial direction of the drive gear 21 and also the second lubricating oil reservoir space Z3 is provided at a position overlapped with the housing space Z1 as viewed along an axial direction of the drive gear 21, the first lubricating oil reservoir space Z2 and the second lubricating oil reservoir space Z3 are distributed in a manner that effectively utilizes space.
[0087] Moreover, a communicating state that restricts the flow of lubricating oil among the housing space, the first lubricating oil reservoir space, and the second lubricating oil reservoir space can be realized with a simple configuration in which the communication holes 71e and 96 are provided on the first partition wall W1 and the second partition wall W2.
[0088] The driven gear 22 is formed by the helical gear and since the communication hole of the first lubricating oil reservoir space is provided on the front side in the rotation direction of the tooth surface of the driven gear 22, the lubricating oil that is supplied from the first lubricating oil reservoir space via the communication hole is easily taken into the housing space by the pumping action of the second gear. As a result, the communication hole can be set to be small in size, so that deterioration of the rigidity of the partition wall can be suppressed while providing the communication hole.
[0089] Moreover, the power transmission mechanism in the present invention is not limited to the one using gears; rather, a wrapping power transmission mechanism may also be used such as a chain or belt drive. In such a case, a sprocket or a pulley as a power transmission member is included instead of the drive gear and the driven gear.
[0090] The present invention is not limited to the exemplified embodiment, without limiting the scope of the present invention, various improvements and design modifications are possible. Thus, it should be understood that the embodiments herein are illustrative and not restrictive, since the scope of the invention is defined by the appended claims rather than by the description preceding them, and all changes that fall within metes and bounds of the claims, or equivalence of such metes and bounds thereof, are therefore intended to be embraced by the claims.
INDUSTRIAL APPLICABILITY
[0091] As discussed above, according to the present invention, since the transfer device mounted on a four-wheel drive vehicle can appropriately control the amount of the lubricating oil of the transfer device according to the traveling conditions of the vehicle, it is possible to be used appropriately in the industrial field of manufacturing such kinds of vehicles.
EXPLANATION OF REFERENCE CHARACTERS
[0092] 10 Transfer device
[0093] 11 Output shaft for rear wheels
[0094] 12 Output shaft for front wheels
[0095] 20 Power transmission mechanism
[0096] 21 Drive gear (first rotation member)
[0097] 22 Driven gear (second rotation member)
[0098] 70 Transfer case (case)
[0099] 71e, 96 Communication hole
[0100] L Oil level when a vehicle stops (Predetermined oil level)
[0101] W1 First partition wall
[0102] W2 Second partition wall
[0103] Z1 Housing space
[0104] Z2 First lubricating oil reservoir space
[0105] Z3 Second lubricating oil reservoir space