JP2006183717A - Differential device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a differential device capable of improving rigidity of a bearing cap without disturbing lubricating action of a pinion shaft. <P>SOLUTION: In this differential device 10 having a carrier 11 rotatably supporting the pinion shaft 13 connected with a propeller shaft 4 through bearings 14, 15, a gear case 20 comprising a ring gear 18 engaged with a pinion 17 of the pinion shaft 13, right and left bearing caps 27, 27 connected with right and left supporting portions of the carrier 11 to rotatably support the case 20 to the carrier 11 through right and left side bearings 25, 25, and a carrier cover 12 mounted on the carrier 11 in a state of including the gear case 20 and the ring gear 18, a bridging member 40 for bridging the caps 27, 27 over the ring gear 18, is mounted between the right and left caps 27, 27, and an oil guide member 45 surrounding an outer peripheral portion of the ring gear 18, is mounted on the bridging member 40. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention belongs to a technical field of a differential device provided in an automobile.

  Generally, as a differential device provided in an automobile such as an FR (front engine rear drive) vehicle or a four-wheel drive vehicle, a differential gear case that houses a differential mechanism therein and includes a ring gear on an outer peripheral portion is provided with a pair of left and right side bearings and There is known an open type differential apparatus having a structure in which a differential carrier is rotatably supported via a bearing cap.

  That is, this differential device has a pinion shaft coupled to a propeller shaft (propulsion shaft) that transmits power from an engine disposed in front, and the pinion shaft is rotatably supported by a differential carrier via a pinion bearing. Yes. The pinion gear provided on the pinion shaft and the ring gear provided on the outer peripheral portion of the differential gear case are meshed with each other so that the rotational axes are orthogonal to each other, and the differential gear case is provided on the left and right sides provided on the differential carrier. A pair of support parts and a pair of left and right bearing caps coupled to the support parts are rotatably supported by the differential carrier via a pair of left and right side bearings. In addition, a carrier cover is attached to the differential carrier, and the differential gear case, ring gear, bearing cap, or the like is enclosed by the carrier cover.

  In this regard, in Patent Document 1, in an open type differential device having a structure in which a differential gear case is supported using a bearing cap as described above, oil scooped up from the bottom of the carrier cover by rotation of the ring gear is disclosed. A lubrication structure for guiding a pair of front and rear pinion bearings of the pinion shaft is disclosed.

JP 2004-204949 A

  By the way, the driving force from the engine input from the propeller shaft to the pinion shaft is transmitted from the driving-side pinion gear to the driven-side ring gear by meshing between the pinion gear and the ring gear, which is a bevel gear set. As the meshing reaction force of torque transmission, the force that tries to keep the bevel gears away from each other acts on the meshing point, and the meshing reaction force is applied to the ring gear or differential gear case on the driven side and the umbrella of the bevel gear set. It acts to push in the direction of the inclined normal line, that is, the laterally oblique rearward direction. As a result, the bearing cap that supports the differential gear case is subjected to a force that pushes the gap between the caps outward, causing the bearing cap to bend outwards, resulting in the ring gear. As a result, the meshing point is displaced from the original position, and a normal tooth contact cannot be obtained, and a gear sound or vibration noise is generated with an irregular meshing of the gear set as an oscillating force. There is a problem that.

  In order to cope with this problem, it is conceivable that the cap is supported from the outside by the carrier cover including the bearing cap. However, in general, the carrier cover is included in consideration of ease of assembly. Since it is mounted on the differential carrier with some clearance between the members, it is not a sufficient measure.

  Therefore, it is only necessary to increase the rigidity of the bearing cap so as to prevent the phenomenon of falling to the outside of the bearing cap, but in that case, by improving the rigidity of the bearing cap, the lubricating action of the pinion shaft, That is, it is necessary to pay attention so that the action of the rotating ring gear guiding the oil scooped up from the bottom of the carrier cover to the pinion bearing of the front pinion shaft is not hindered.

  The present invention solves the above-mentioned problems in the differential device, and enhances the rigidity of the bearing cap without inhibiting the lubrication action of the pinion shaft so as to suppress the phenomenon of overturning the bearing cap. It is an object of the present invention to provide a differential device in which countermeasures are taken.

  That is, in order to solve the above-described problem, the invention according to claim 1 of the present application includes a pinion shaft connected to a propulsion shaft, a differential carrier that rotatably supports the pinion shaft via a pinion bearing, and the pinion A differential gear case having a ring gear meshing with a pinion gear provided on the shaft on the outer peripheral portion, and provided on the differential carrier for rotatably supporting the differential gear case on the differential carrier via a pair of left and right side bearings A differential having a pair of left and right support portions, a pair of left and right bearing caps coupled to the support portions, and a carrier cover mounted on the differential carrier so as to enclose the differential gear case and the ring gear. A bridging member for bridging the caps across the ring gear is provided between the pair of left and right bearing caps, and the bridging member is scraped from the bottom of the carrier cover by the rotation of the ring gear. An oil guide member for guiding the generated oil to the pinion bearing is provided so as to surround an outer peripheral portion of the ring gear.

  Next, according to a second aspect of the present invention, in the first aspect of the present invention, the rotational axis of the ring gear is offset upward from the rotational axis of the pinion gear, and the bridging member is The ring gear is provided so as to be offset downward from the rotational axis of the ring gear.

  The invention described in claim 3 is the invention described in claim 1 or 2, wherein the bridging member is integrally formed with the pair of left and right bearing caps.

  First, according to the first aspect of the present invention, in the open type differential device having a structure in which the differential gear case is rotatably supported by the differential carrier by the bearing cap, the ring gear is straddled between the pair of left and right bearing caps. Since the bridging member that bridges the bearing caps is provided, the rigidity of the bearing cap is enhanced, the phenomenon of falling to the outside of the bearing cap is prevented, not only the generation of gear noise or vibration noise due to improper engagement of the gear set, Various problems such as a decrease in the strength of the ring gear and a decrease in the life of the side bearing are suppressed.

  In addition, since the bridge member is provided with an oil guide member that surrounds the outer periphery of the ring gear, the guide member guides the oil scraped up from the bottom of the carrier cover by the rotation of the ring gear to the pinion bearing of the pinion shaft. It is also possible to prevent the lubricating action of the pinion shaft from being hindered. That is, in order to effectively improve the rigidity of the bearing cap, it is important to shorten the cross-linking length of the cross-linking member as much as possible to reduce the deformation amount of the cross-linking member itself. The bridging member straddling is close to the ring gear, so that the oil scraped up by the ring gear hits the bridging member and may not reach the pinion bearing of the pinion shaft. Therefore, by providing an oil guide member so as to surround the outer periphery of the ring gear, it is possible to avoid the oil scraped up by the rotation of the ring gear from hitting the bridging member and to reach the front pinion bearing without any trouble. It was a countermeasure.

  Next, according to the second aspect of the present invention, the gear set of the drive-side pinion gear and the driven-side ring gear offsets the rotation axis of the ring gear orthogonal to each other above the rotation axis of the pinion gear. In the case of a gear set having a structure, since the bridging member is offset below the rotational axis of the ring gear, the bridging member is the same as the meshing point of the gear set with respect to the rotational axis of the ring gear. In this way, the rigidity of the bearing cap can be effectively improved on the lower side where the force that pushes the gap between the left and right bearing caps outward increases. It becomes possible.

  According to the invention described in claim 3, since the bridging member for improving the rigidity of the bearing cap is integrally formed with the bearing cap, for example, the bridging member is formed separately from the bearing cap, and both The rigidity of the bearing cap can be further improved as compared with the case where these are coupled by appropriate means. Hereinafter, the present invention will be described in more detail through the best mode of the present invention.

  As shown in FIG. 1, in the present embodiment, a differential device 10 according to the present invention is provided in an FR (front engine rear drive) vehicle 1. That is, the driving force from the engine 2 placed vertically in front of the vehicle body is input to the differential device 10 via the transmission 3 and the propeller shaft 4, and the differential device 10 drives the left and right rear drive shafts 5, 5. Torque is distributed to 6.

  Hereinafter, the configuration of the differential device 10 will be described in detail with reference to FIGS. First, as shown in FIG. 2, the differential apparatus 10 has an overall shape composed of a front differential carrier 11 and a rear carrier cover 12. A pinion shaft 13 extending in the front-rear direction is rotatably supported by the carrier 11 by a pair of front and rear pinion bearings (a front bearing 14 and a rear bearing 15). A companion flange 16 is coupled to the front end portion of the pinion shaft 13, and the rear end portion of the propeller shaft 4 is coupled to the flange 16. A drive pinion 17 is integrally formed at the rear end portion of the pinion shaft 13, and the drive pinion 17 meshes with a ring gear 18.

  The ring gear 18 is fastened to the outer periphery of the differential gear case 20 with bolts 21. The gear case 20 accommodates a pinion shaft 22, pinion gears 23 and 23, and side gears 24 and 24 inside. Although not shown, one end of the left and right drive shafts 5 and 6 is spline fitted to the side gears 24 and 24.

  The gear case 20 is rotatably supported by the carrier 11 via a pair of left and right side bearings 25, 25 that are tapered roller bearings. That is, as clearly shown in FIG. 3, a pair of left and right support portions 26 and 26 (only the right support portion is shown in FIG. 3) protruding rearward are provided on the rear end surface of the carrier 11. 26 and 26, a pair of left and right bearing caps 27 and 27 are coupled with bolts 28. In this case, the support portions 26 and 26 and the caps 27 and 27 cooperate with each other to form the semicircular recesses 26a and 26a for sandwiching the side bearings 25 and 25 and the left and right boss portions 20a and 20a of the gear case 20: A halved structure is formed with 27a and 27a.

  2 and 4, a pair of left and right adjuster rings 29 and 29 are screwed to the support portions 26 and 26 and the caps 27 and 27 on the outer side of the side bearings 25 and 25. The rings 29 and 29 are for adjusting the meshing point between the ring gear 18 and the drive pinion 17 by changing the position of the gear case 20 and hence the ring gear 18 in the left-right direction. The adjuster ring 29 is provided with a number of notches 29a... 29a, and the claw of the lock plate 30 engages with one of the notches 29a to prevent the ring 29 from rotating. The lock plate 30 is fixed to the cap 27 with bolts 31 via a bridging member 40 described later.

  As shown in FIG. 2, the carrier cover 12 is mounted on the rear end surface of the carrier 11 so as to enclose all of the gear case 20, the ring gear 18, the caps 27, 27, the bridging member 40, and the like. The left and right side walls of the carrier cover 12 are provided with openings 12a and 12a through which the left and right drive shafts 5 and 6 are inserted.

  In addition to the above configuration, a bridging member 40 for bridging the caps 27, 27 is assembled between the bearing caps 27, 27. In this embodiment, the bridging member 40 is formed separately from the caps 27 and 27. The bridging member 40 includes a bridging portion 41 that straddles the ring gear 18 and a pair of left and right base portions 42 and 42 that are continuous with both ends of the bridging portion 41 and overlapped with the upper surfaces of the caps 27 and 27. 42 and 42 are fastened together with the bearing caps 27 and 27 and the support portions 26 and 26 by the bolts 28 to 28 (see FIGS. 3 and 4).

  Here, as clearly shown in FIGS. 3 and 5, the gear set of the drive pinion 17 and the ring gear 18 has a high meshing rate, and the rotational axis of the ring gear 18 is realized so that smooth meshing is realized. The drive pinion 17 is disposed so as to be offset above the rotational axis (hypoid gear set). Correspondingly, the bridging member 40, particularly the bridging portion 41, is arranged offset below the rotational axis of the ring gear 18.

  Further, an oil guide member 45 is provided on the bridging member 40. 3 and 4, the guide member 45 extends in an arc shape by a predetermined length in the circumferential direction of the ring gear 18 so as to surround the outer peripheral portion of the ring gear 18. As a result, the guide member 45 guides the oil scooped up from the bottom of the carrier cover 12 by the rotation of the ring gear 18 to the pinion bearings 14 and 15.

  As described above, in the present embodiment, in the open type differential device 10 having a structure in which the gear case 20 is rotatably supported by the carrier 11 by the bearing caps 27, 27, the ring gear 18 is disposed between the pair of left and right caps 27, 27. Since the bridging member 40 for bridging the caps 27 and 27 is provided so as to straddle, the rigidity of the caps 27 and 27 is increased. Therefore, even if the meshing reaction force of the bevel gear sets 17 and 18 acts to push the ring gear 18 or the gear case 20 on the driven side in the obliquely rearward direction as shown by the arrow A in FIG. (In the case of this example, the left cap in particular) The phenomenon of falling outward of the 27 is prevented, and not only the generation of gear noise or vibration noise due to improper meshing of the gear sets 17 and 18, but also the strength of the ring gear 18 is reduced. Various troubles such as a decrease in the life of the side bearings 25, 25 are suppressed.

  In addition, since the oil guide member 45 surrounding the outer periphery of the ring gear 18 is provided on the bridging member 40, the oil scraped up from the bottom of the carrier cover 12 by the rotation of the ring gear 18 (FIG. 3). In addition, the oil surface is indicated by the symbol X and the oil scooping direction is indicated by the arrow B) can be guided to the front bearing 14 and the rear bearing 15 of the pinion shaft 13 (FIG. 3 shows a guide member 45). The direction in which the oil that has spilled out is indicated by arrow C) prevents the lubricating action of the pinion shaft 13 from being hindered.

  That is, in order to effectively improve the rigidity of the caps 27 and 27, it is important to reduce the amount of deformation of the bridging member 40 itself by reducing the bridging length of the bridging member 40 as much as possible. Then, the bridging portion 41 straddling the ring gear 18 comes close to the ring gear 18, and the oil scraped up by the ring gear 18 may hit the bridging portion 41 and not reach the pinion bearings 14 and 15 of the pinion shaft 13. There is. Therefore, an oil guide member 45 is provided so as to surround the outer peripheral portion of the ring gear 18, thereby preventing the oil scraped up by the rotation of the ring gear 18 from hitting the bridging portion 41, so that the oil is moved to the front pinion. Measures were taken to reach the bearings 14 and 15 without hindrance.

  Further, since the bridging portion 41 is provided by being offset downward from the rotational axis of the ring gear 18, the bridging portion 41 is engaged with the gear set 17, 18 with respect to the rotational axis of the ring gear 18. Thus, the cap 27, on the lower side where the force (see arrow A in FIG. 2) that pushes the gap between the left and right caps 27, 27 outwards works more greatly. 27 can be effectively improved in rigidity.

  The above embodiment is the best embodiment of the present invention, but it goes without saying that various modifications and changes can be made without departing from the scope of the claims. For example, a bridging member 40 for improving the rigidity of the bearing caps 27, 27 may be formed integrally with the caps 27, 27. Thereby, the rigidity of the bearing caps 27 and 27 is further improved.

  A plurality of bridging portions 41 straddling the ring gear 18 may be provided. FIG. 6 is an example in which two bridging portions, an upper bridging portion 41a straddling the ring gear 18 at the upper side and a lower bridging portion 41b straddling the lower side, are provided. Since the meshing point between the drive pinion 17 and the ring gear 18 is on the lower side, the size (width, thickness, etc.) of the lower bridging portion 41b is set to make the lower bridging portion 41b more rigid than the upper bridging portion 41a. Is relatively large. Further, in order to avoid interference between the bridging portions 41a and 41b and the ring gear 18, cuts 41c and 41d are made in the inner edge portions of the bridging portions 41a and 41b.

  Further, as shown in FIG. 7, when the cross-sectional shape of the oil guide member 45 is approximated to the cross-sectional shape of the ring gear 18 and both the members 45 and 18 are brought close to each other, the oil scraped up by the ring gear 18 is removed from the back surface of the guide member 45. As a result, the amount of oil used for lubrication can be secured.

  As described above in detail with reference to specific examples, according to the present invention, the rigidity of the bearing cap is increased without hindering the lubricating action of the pinion shaft, and the phenomenon of falling outside the bearing cap is suppressed. Thus, a differential apparatus in which countermeasures are taken is provided. INDUSTRIAL APPLICABILITY The present invention has wide industrial applicability in the technical field of differential devices provided in automobiles such as FR vehicles and four-wheel drive vehicles, in particular, open type differential devices having a structure in which a differential gear case is supported using a bearing cap. Have

It is a top view of the vehicle 1 provided with the differential apparatus 10 which concerns on embodiment of this invention. 2 is an enlarged plan sectional view of the differential device 10. FIG. However, the periphery of the pinion shaft 13 has a plane including the rotation axis of the shaft 13 as a cut surface, and the periphery of the gear case 20 has a plane including the rotation axis of the case 20 as a cut surface. 2 is an enlarged longitudinal sectional view of the differential device 10. FIG. However, it is along arrow III-III in FIG. It is the expansion perspective view which looked at the said differential apparatus 10 from the lower right back (in the arrow IV direction of FIG.2 and FIG.3). However, the carrier cover 12 is in a removed state. (A) is the rear view which looked at the bridging member 40 from back, (b) is the schematic rear view which looked at the differential apparatus 10 from the back which showed the mounting state of this bridging member 40 with the dashed line. . However, the carrier cover 12 is in a removed state. (A) is the rear view which looked at the bridge | crosslinking member 40 which concerns on another embodiment from back, (b) is the said differential apparatus 10 which showed the mounting state of this bridge | crosslinking member 40 with the chain line from back. FIG. However, the carrier cover 12 is in a removed state. FIG. 5 is a partial plan sectional view similar to FIG. 2, showing a modification of the oil guide member 45.

Explanation of symbols

4 Propeller shaft (propulsion shaft)
DESCRIPTION OF SYMBOLS 10 Differential apparatus 11 Differential carrier 12 Carrier cover 13 Pinion shaft 14,15 Pinion bearing 17 Drive pinion (pinion gear)
18 ring gear 20 differential gear case 25 side bearing 26 support part 27 bearing cap 40 bridging member 41 bridging part 42 base 45 oil guide member

Claims (3)

  A pinion shaft connected to the propulsion shaft, a differential carrier that rotatably supports the pinion shaft via a pinion bearing, a differential gear case having a ring gear that meshes with a pinion gear provided on the pinion shaft, A pair of left and right support portions provided on the differential carrier to rotatably support the differential gear case on the differential carrier via a pair of left and right side bearings; and a pair of left and right bearing caps coupled to the support portion; A differential device having a carrier cover mounted on the differential carrier so as to enclose the differential gear case and the ring gear, the pair of bearing caps, A bridging member for bridging the caps across the ring gear is provided, and an oil guide member for guiding oil scraped up from the bottom of the carrier cover by rotation of the ring gear to the pinion bearing is provided on the bridging member. A differential device characterized in that it is provided so as to surround an outer peripheral portion thereof.   The rotation axis of the ring gear is provided offset above the rotation axis of the pinion gear, and the bridging member is provided offset below the rotation axis of the ring gear. The differential device according to claim 1. The differential device according to claim 1, wherein the bridging member is integrally formed with the pair of left and right bearing caps.

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