JP6636878B2 - Power transmission device - Google Patents

Description

  The present invention relates to a power transmission device.

  BACKGROUND ART Conventionally, a power transmission device including a final driven gear that meshes with a final drive gear, a case that rotatably supports the final driven gear via a bearing, and a transfer device is known (for example, see Patent Document 1). .

  A transfer input gear that meshes with the final driven gear, a transfer input shaft that supports the transfer input gear, a first bevel gear that is supported by the transfer input shaft, a second bevel gear that meshes with the first bevel gear, A transfer output shaft that supports the second bevel gear.

JP-A-2015-168392

  In a final driven gear of a conventional power transmission device, two gears, a final driven gear and a transfer input gear, mesh with each other. Therefore, in order to sufficiently lubricate the two meshing portions with the lubricating fluid by the lubricating fluid that the final driven gear scrapes up, it is necessary to enlarge the case.

  In view of the above, an object of the present invention is to provide a power transmission device that can appropriately lubricate two meshing portions with a lubricating fluid while suppressing an increase in the size of a case.

In order to achieve the above object, the present invention provides
A final driven gear (for example, final driven gear 44 of the embodiment; hereinafter the same) meshing with a final drive gear (for example, final drive gear 30 of the embodiment; the same applies hereinafter);
A case (for example, a transmission case 61 of the embodiment; hereinafter the same) for rotatably supporting the final driven gear via a bearing (for example, the bearings 43a and 43b of the embodiment; the same applies hereinafter);
A transfer device (for example, the transfer device 5 of the embodiment; the same applies hereinafter);
(For example, the power transmission device PT of the embodiment; the same applies hereinafter),
The transfer device is
A transfer input gear that meshes with the final driven gear (for example, the transfer input gear 56 of the embodiment; the same applies hereinafter);
A transfer input shaft that supports the transfer input gear (for example, the transfer input shaft 55 of the embodiment; the same applies hereinafter);
A first bevel gear (for example, the first bevel gear 57 of the embodiment; the same applies hereinafter) supported by the transfer input shaft;
A second bevel gear that meshes with the first bevel gear (for example, the second bevel gear 85 of the embodiment; the same applies hereinafter);
A transfer output shaft that supports the second bevel gear (for example, the transfer output shaft 82 of the embodiment; the same applies hereinafter);
With
The transfer input gear meshes with the final driven gear above a rotation center of the final driven gear,
The case has a recessed portion (for example, the recessed portion 61a of the embodiment; the same applies hereinafter) corresponding to a portion where the final driven gear and the transfer input gear mesh with each other, in the direction of the rotation center axis of the final driven gear toward the transfer device. .) it is provided,
The recessed portion avoids a portion where the final driven gear and the transfer input gear mesh with each other, and a part of the lubricating splash which the final driven gear scrapes up to a meshing portion of the final driven gear which meshes with the final drive gear. It is characterized by leading .

According to the present invention, since the case is provided with the recessed portion corresponding to the portion where the final driven gear and the transfer input gear mesh with each other, at least a part of the lubricating fluid scraped up by the final driven gear is supplied to the final driven gear. In such a manner that it can enter the recessed portion so as to avoid the portion where the gear and the transfer input gear mesh with each other, it can reach the portion where the final drive gear and the final driven gear mesh with each other through the recessed portion. Therefore, it is possible to appropriately lubricate the portions where the final drive gear, the final driven gear, and the transfer input gear mesh with each other while suppressing an increase in the size of the case.
Further, in the present invention, the lower end of the concave portion is located below a portion where the final driven gear and the transfer input gear mesh with each other, and the upper end of the concave portion is the final driven gear and the transfer input gear. Is preferably located above the portion where the gears mesh.

FIG. 1 is a schematic diagram of a power transmission system of a four-wheel drive vehicle. FIG. 2 is a skeleton diagram of the power transmission device. Explanatory drawing which shows the inside of one side of a transmission case. Explanatory drawing which shows the flow of lubricating oil inside one side of the transmission case. Explanatory drawing which shows the other inside of a transmission case. Explanatory drawing which shows the flow of the lubricating oil inside the other inside of a transmission case. Explanatory drawing which shows the flow of the lubricating oil inside a transmission case. Sectional drawing which shows a transfer apparatus. FIG. 4 is an explanatory diagram showing a transfer input shaft of the transfer device. Explanatory drawing which shows a transfer cover from one side. FIG. 4 is an enlarged perspective view showing a part of the transfer cover. Explanatory drawing which shows a transfer cover from the other side. FIG. 3 is an explanatory diagram showing a transfer output shaft of the transfer device. FIG. 4 is an explanatory diagram showing a part of the transfer case where a transfer output shaft is inserted, with a part cut away.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  As shown in FIG. 1, the engine E (internal combustion engine, drive source) is mounted on the vehicle body horizontally so that the crankshaft 1 faces the left and right direction of the vehicle body. A power transmission device PT for transmitting the driving force of the engine E to the left and right front wheels WFL, WFR and the left and right rear wheels WRL, WRR includes a torque converter 2 connected to a crankshaft 1 and a transmission 3 connected to the torque converter 2. , A front differential gear 4 connected to the transmission 3, a transfer device 5 connected to the front differential gear 4, and a rear differential gear 6 connected to the transfer device 5.

  The front differential gear 4 is connected to left and right front wheels WFL, WFR via a front left axle 7L and a front right axle 7R. The rear differential gear 6 is connected to a transfer device 5 via a propeller shaft 8, and connected to left and right rear wheels WRL, WRR via a rear left axle 9L and a rear right axle 9R.

  Next, as shown in FIG. 2, the transmission 3 includes a main shaft MS, a secondary shaft SS, and a counter shaft CS which are arranged in parallel with each other and extend in the left-right direction of the vehicle body.

  A main drive gear 21 is fixed to the main shaft MS, and a main third speed gear 22 which can be coupled to the main shaft MS by a third speed clutch C3, and a main shaft formed integrally with a fourth speed / reverse clutch C4R. A main fourth speed gear 23 and a main reverse gear 24 that can be coupled to the MS are rotatably supported.

  A secondary driven gear 25 is fixed to the secondary shaft SS, and a secondary first speed gear 26 that can be connected to the secondary shaft SS by a first speed clutch C1 and a secondary second speed that can be connected to the secondary shaft SS by a second speed clutch C2. The gear 27 is rotatably supported.

  A counter second gear 28, a counter third gear 29, and a final drive gear 30 are fixedly mounted on the counter shaft CS, and a counter idle gear 31, a counter fourth gear 32, and a counter reverse gear 33 are rotatable. Supported. Further, a first-speed counter gear 34 that can be coupled to the counter shaft CS via the first-speed hold clutch CLH is rotatably supported.

  A reverse idle gear 35 meshes with the main reverse gear 24 and the counter reverse gear 33. The first counter gear 34 can be connected to the third counter gear 29 via a one-way clutch COW, and the fourth counter gear 32 and the counter reverse gear 33 are selectively connected to the counter shaft CS via a selector 36. Can be combined.

  The main drive gear 21 meshes with the counter idle gear 31, and the counter idle gear 31 meshes with the secondary driven gear 25. The rotation of the crankshaft 1 of the engine E is transmitted to the secondary shaft SS via the torque converter 2, the main shaft MS, the main drive gear 21, the counter idle gear 31, and the secondary driven gear 25.

  Therefore, when the secondary first-speed gear 26 rotatably supported on the secondary shaft SS is coupled to the secondary shaft SS by the first-speed clutch C1, the rotation of the secondary shaft SS changes to the first-speed clutch C1, the secondary first-speed gear 26, The transmission is transmitted to the counter shaft CS via the one-way clutch COW and the counter third speed gear 29, and the first speed is established. The first-speed clutch C1 is maintained in the engaged state even when the second to fourth speeds are established, but the one-way clutch COW slips when the second to fourth speeds are established.

  When the secondary second-speed gear 27 rotatably supported by the secondary shaft SS is coupled to the secondary shaft SS by a second-speed clutch C2, the rotation of the secondary shaft SS changes to the second-speed clutch C2, the secondary second-speed gear 27, and the counter second-speed gear. The transmission is transmitted to the counter shaft CS via the second gear 28, and the second speed is established.

  When the main third speed gear 22 rotatably supported on the main shaft MS is coupled to the main shaft MS by a third speed clutch C3, the rotation of the main shaft MS is changed to the third speed clutch C3, the main third speed gear 22, and the counter third speed gear. The transmission is transmitted to the counter shaft CS via the transmission 29, and the third speed is established.

  A counter fourth speed gear 32 rotatably supported on the counter shaft CS is coupled to the counter shaft CS by a selector 36, and a main fourth speed gear 23 rotatably supported on the main shaft MS is connected to a fourth speed-reverse clutch. When coupled to the main shaft MS at C4R, the rotation of the main shaft MS is transmitted to the counter shaft CS via the fourth speed-reverse clutch C4R, the main fourth speed gear 23, the counter fourth speed gear 32, and the selector 36, and the fourth speed shift is performed. Steps are established.

  While the counter reverse gear 33 rotatably supported on the counter shaft CS is coupled to the counter shaft CS by the selector 36, the main reverse gear 24 rotatably supported on the main shaft MS is connected to the fourth reverse clutch C4R. When coupled to the main shaft MS, the rotation of the main shaft MS is transmitted to the counter shaft CS via the fourth speed-reverse clutch C4R, the main reverse gear 24, the reverse idle gear 35, the counter reverse gear 33, and the selector 36, and the reverse shift is performed. Steps are established.

  When the first-speed hold clutch CLH is engaged with the first-speed clutch C1 engaged, the first-speed hold shift speed is established. If the first-speed hold shift stage is established when strong engine braking is required, even if the one-way clutch COW slips, the torque of the rear wheels WRL, WRR is transmitted back to the engine E via the first-speed hold clutch CLH. can do.

  Next, the structure of the front differential gear 4 will be described.

  As shown in FIG. 2, the front differential gear 4 includes a differential case 43 rotatably supported by a transmission case 61. A final driven gear 44 that meshes with the final drive gear 30 provided on the counter shaft CS is fixed to the outer periphery of the differential case 43.

  The rotation of the counter shaft CS of the transmission 3 is transmitted to the differential case 43 via the final drive gear 30 and the final driven gear 44, and the rotation of the differential case 43 is changed according to the load on the left and right front wheels WFL, WFR. 7L and the front right axle 7R.

  A front left output shaft 47L connected to the front left axle 7L and a front right output shaft 47R connected to the front right axle 7R are relatively rotatably fitted to the differential case 43, and the two output shafts 47L, 47R are connected to each other. Differential side gears 48, 48 are spline-coupled to the opposing ends, respectively. A pair of pinion gears 51, 51 meshing with the two differential side gears 48, 48 are rotatably supported by a pinion shaft 50 fixed inside the differential case 43 so as to be orthogonal to the two output shafts 47L, 47R.

  Referring to FIG. 3, the transmission case 61 accommodating the front differential gear 4 of the present embodiment has a rotation of the final driven gear 44 corresponding to a portion where the final driven gear 44 and the transfer input gear 56 formed of a helical gear mesh with each other. A concave portion 61a that is concave in a semicircular cross section is provided on the transfer device 5 side in the center axis direction.

  The recess 61a lifts up the lubricating oil by the final driven gear 44 whose lower end is immersed in a lubricating oil reservoir that collects at the bottom of the transmission case 61. The lubricating oil that has passed through the recessed portion 61a without being hindered by the portion where the transfer input gear 56 formed of the helical gear meshes with the final driven gear 44 and the portion where the final drive gear 30 meshes without being disturbed. I can guide you.

  Further, the transmission case 61 includes one of the two bearings 43a and 43b (right side in FIGS. 1 and 2) that supports the differential case 43 from the bottom of the semi-circular recess. A bearing lubrication groove 61b is provided as a guide groove for splash lubrication oil extending upward. Due to the bearing lubrication groove 61b, a part of the splash lubricating oil that has entered the recess 61a passes through the bearing lubrication groove 61b and above the bearing 43a on the transfer device 5 side (one side, the right side in FIGS. 1 and 2). And falls on the side wall 61c provided so as to be guided to the bearing 43a.

  In the transmission case 61, a delivery rib 61 d is provided on an inner wall surface of the transmission case 61 located above the front differential gear 4 and extends downward and extends in the rotation axis direction of the final driven gear 44. Part of the splash lubricating oil passing through the bearing lubrication groove 61b hits the delivery rib 61d. The transfer rib 61d extends above the bearing 43b on the opposite side (the other side, the left side in FIGS. 1 and 2). A lower end of the transfer rib 61d is provided with a claw 61e bent so as to bend toward the recess 61a. The lubricating oil attached to the transfer rib 61d is prevented from being easily dropped by the claw 61e, and the lubricating oil is easily guided to the bearing 43b on the opposite side (the other side) as shown in FIG. Then, the bearing 43b on the opposite side (the other side) is lubricated by the lubricating oil dropped along the transfer rib 61d.

  In the transmission case 61, the lubricating oil moved to the opposite side (the other side) by the delivery rib 61d is appropriately guided to the bearing 43b on the opposite side (the other side) so as to be opposite to the delivery rib 61d (the other side). A guide protrusion 61f is provided below the end of the bearing 43b to receive the lubricating oil dropped and guide it to the bearing 43b on the opposite side (the other side). By the guide projection 61f, the lubricating oil guided via the transfer rib 61d can be appropriately guided to the bearing 43b on the opposite side (the other side) by the guide projection 61f.

  A part of the splash lubricating oil that has entered the recess 61a is stored in an oil reservoir 61g provided above the transfer input gear 56 formed of a helical gear of the transfer input shaft 55, and penetrates as a guide. Lubricating oil is guided from the hole 61h to the transfer device 5.

  Next, the structure of the transfer device 5 of the present embodiment will be described.

  As shown in FIG. 8, the rotation of the final driven gear 44 is transmitted to the second bevel gear 85 of the transfer output shaft 82 via the transfer input gear 56 composed of the helical gear of the transfer input shaft 55 and the first bevel gear 57. The transfer input gear 56 meshes with the final driven gear above the rotation center of the final driven gear 44. As a result, a space can be provided below the transfer device 5, and the layout flexibility of vehicle components can be improved. A transfer output shaft 82 transmits rotation to the propeller shaft 8 (see FIG. 1).

  A transfer case 62 is fixed to a right side surface of a transmission case 61 (specifically, a torque converter case forming a part of the transmission case). The transfer case 62 includes a transfer case main body 63 and a transfer cover 64.

  The transfer case main body 63 and the transfer cover 64 are configured by being integrally fastened with a plurality of bolts 66 while being positioned by the knock pins 65. The sub-assembled transfer case 62 is fastened to the transmission case 61 by a plurality of bolts 67 penetrating the transfer case main body 63 and the transfer cover 64.

  The transfer cover 64 fits into a support hole 61i (recess) of the transmission case 61. With the transfer cover 64 fitted in the support hole 61i, the transfer case 62 is fixed to the transmission case 61 with bolts 67.

  The transfer input gear 56 is spline-fitted to the left end of the transfer input shaft 55 extending in the left-right direction of the vehicle body, and is fixed between the washer 59 and the inner race of the tapered roller bearing 71 by a nut 58. The transfer input shaft 55 integrally has a first bevel gear 57 at the right end.

  The transfer input shaft 55 is supported by a pair of tapered roller bearings 70, 71 provided on the inner peripheral surface of the transfer cover 64. The inner race of the tapered roller bearing 70 on the right side is locked to a step 55a (the back surface of the first bevel gear 57) at the boundary between the transfer input shaft 55 and the first bevel gear 57.

  The outer race of the right tapered roller bearing 70 is locked to the step 64 a of the transfer cover 64. The inner race of the left tapered roller bearing 71 is locked between the transfer input gear 56 (helical gear) and the step 55b of the transfer input shaft 55. The outer race of the left tapered roller bearing 71 is locked by the step 64b of the transfer cover 64.

  The leftward thrust force of the transfer input shaft 55 is received by the step 64a of the transfer cover 64 from the first bevel gear 57 via the tapered roller bearing 70. The rightward thrust force of the transfer input shaft 55 is received by the step 64b of the transfer cover 64 via the transfer input gear 56 and the tapered roller bearing 71. The preload of the pair of tapered roller bearings 70, 71 can be adjusted by tightening the nut 58 and attaching a shim to the step 55b of the transfer input shaft 55.

  A transfer output shaft 82 extending in the front-rear direction is supported by the transfer case main body 63 via a pair of tapered roller bearings 83 and 84, and a second bevel gear 85 provided at a front end thereof meshes with the first bevel gear 57. A coupling 86 to which the front end of the propeller shaft 8 is coupled is spline-coupled to the rear end of the transfer output shaft 82, and is fixed with a nut 87.

  As shown in FIG. 9, the lubricating oil flowing from the transmission case 61 through the through hole 61 h as a guide portion is the inner peripheral surface of the support hole 61 i of the transmission case 61 and the outer peripheral surface of the transfer cover 64. Is temporarily stored in an annular groove 68 provided in the rim. As shown in FIG. 10 from the direction of the rotation center axis of the transfer input shaft 55, an annular groove 68 provided on the outer peripheral surface of the transfer cover 64 and the inner peripheral surface of the transfer cover 64 are provided on the right side of FIG. A communication hole 64c is formed to communicate with. A notch 64d is provided on the inner peripheral surface of the transfer cover 64 so as to guide the lubricating oil between the tapered roller bearings 70 and 71 so that the lubricating oil can bypass the outer surface of the tapered roller bearing 70.

  The one-dot chain line in FIG. 10 shows a cut section in FIG. FIG. 11 shows the communication hole 64c in an enlarged manner. FIG. 12 is a perspective view showing the transfer cover 64 from the opposite side of FIG. The lubricating oil accumulated in the annular groove 68 is supplied into the transfer device 5 through the communication hole 64c.

  As shown in FIG. 9, an annular weir 69 extending radially inward is provided on the inner peripheral surface of the transfer cover 64 to suppress the flow of lubricating oil returning to the front differential gear 4. I have. With this weir portion 69, it is possible to suppress the outflow of the lubricating oil (fluid) from the inside of the transfer device 5 to the transmission case 61, and to appropriately maintain the amount of the lubricating oil in the transfer device 5.

  FIG. 13 is an explanatory diagram showing the transfer output shaft 82 in a partial cross section. FIG. 14 is an explanatory view showing a portion of the transfer case main body 63 accommodating the transfer output shaft 82 in a rotation center axis direction of the transfer output shaft 82 from the front side of the vehicle. The dashed line in FIG. 14 shows the cut section of FIG.

  As shown in FIGS. 13 and 14, the transfer case main body 63 is scraped up by the first and second bevel gears 57 and 85 between two tapered roller bearings 83 and 84 supporting the transfer output shaft 82. A notch 63a for guiding a part of the lubricating oil is provided.

  Of the two tapered roller bearings 83 and 84 supporting the transfer output shaft 82, the lubricating oil discharged rearward from the tapered roller bearing 84 on the rear side of the vehicle in the direction of the rotation center axis of the transfer output shaft 82 is a tapered roller. A return groove 63b is provided in the transfer case main body 63 so as to return between the bearings 83 and 84.

  Further, among the two tapered roller bearings 83 and 84 that support the transfer output shaft 82, the tapered roller bearings 83 and 84 in the rotation center axis direction of the transfer output shaft 82 and on the front side of the vehicle are provided. In order to appropriately maintain the amount of lubricating oil during the period, a suppression plate 88 for suppressing discharge from the tapered roller bearing 84 is provided. Thereby, the amount of lubricating oil between the tapered roller bearings 83, 84 can be maintained at an appropriate amount, and the tapered roller bearings 83, 84 can be sufficiently lubricated.

  Although the illustrated embodiment has been described above, the present invention is not limited to this, and appropriate design changes can be made.

3 Transmission 4 Front differential gear 43 Differential case 43a, 43b Bearing 5 Transfer device 55 Transfer input shaft 56 Transfer input gear (helical gear)
57 First bevel gear 61 Transmission case 61a Recess 61b Bearing lubrication groove 61c Side wall 61d Transfer rib 61e Claw 61f Guide protrusion 61g Oil reservoir 61h Through hole (guide)
61i Support hole 62 Transfer case 63 Transfer case body 63a Notch 63b Return groove 64 Transfer cover 64a, 64b Step 64c Communication hole 64d Notch 68 Annular groove 69 Weir 70, 71 Taper roller bearing 82 Transfer output shaft 83, 84 Taper Roller bearing 85 Second bevel gear 88 Suppression plate E Engine PT Power transmission device WFL, WFR Left and right front wheels WFL, WFR Left and right rear wheels

Claims (2)

A final driven gear that meshes with the final drive gear,
A case that rotatably supports the final driven gear via a bearing,
A transfer device,
A power transmission device comprising:
The transfer device,
A transfer input gear meshing with the final driven gear,
A transfer input shaft that supports the transfer input gear,
A first bevel gear that is supported by the transfer input shaft;
A second bevel gear meshing with the first bevel gear;
A transfer output shaft that supports the second bevel gear;
With
The transfer input gear meshes with the final driven gear above a rotation center of the final driven gear,
The case is provided with a recessed portion that is recessed toward the transfer device in the rotation center axis direction of the final driven gear, corresponding to a portion where the final driven gear and the transfer input gear mesh with each other,
The recessed portion avoids a portion where the final driven gear and the transfer input gear mesh with each other, and a part of the lubricating splash which the final driven gear scrapes up to a meshing portion of the final driven gear which meshes with the final drive gear. A power transmission device characterized by guiding .   The power transmission device according to claim 1,
  The lower end of the recess is located below a portion where the final driven gear and the transfer input gear mesh with each other,
  A power transmission device, wherein an upper end of the concave portion is located above a portion where the final driven gear and the transfer input gear mesh with each other.