JPH0333539A - Mounting method for differential gear - Google Patents

Abstract

PURPOSE:To suppress increase of knocking noise of teeth and make torque control easy by arranging that rotation starting torque becomes a set value allowing specified load to act from the side of a driving small gear on the side of one end to the side of other end when fastening a fastening device on the side of other end of a driving shaft for final deceleration. CONSTITUTION:After a drive shaft 6 is mounted to the diff-carrier 4 of a differential gear 2, a switching dog 90 is outwardly mounted from the side of the other end of the drive shaft 6, and a clamping nut 10 is fastened to a thread part 12, causing deformation in a spacer 38 interposed between inner rings 20 and 30, and giving pre-load to bearings 14 and 16. At this time, load of specified value is allowed to act of the drive shaft 6 from the side of one end of a drive pinion 8 to the side of the thread part 12 on the side of other end. Allowing the load of specified value to act on the drive shaft 6 like this, assembling is performed by fastening the clamping nut 10 to the thread part 12 so that the rotation drive torque of the pinion 8 becomes the set value, the rotation starting torque is confirmed that it is in the set value, and the clamping nut 10 is fixed with an additional fastener 98.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention relates to a method for assembling a differential device, and in particular to a first tapered roller bearing for a drive shaft and a drive shaft, which is provided with a final reduction drive shaft pivotally supported on a differential carrier. The present invention relates to a method for assembling a differential device that can prevent preload applied to a second tapered roller bearing for a shaft from being released after actual running.

[Conventional technology]

The driving force of an internal combustion engine installed in a vehicle such as a car, for example, a vehicle with a front-mounted internal combustion engine and rear wheel drive system, is converted into the desired torque and rotational speed by a transmission and then sent to a differential device via a propulsion shaft. The power is transmitted to the left and right axles, respectively, and drives the left and right wheels.

The differential device is constructed as shown in FIG. In the figure, 102 is a differential device, 1
04 is a differential carrier, and 106 is a drive shaft which is a drive shaft for final reduction. The drive shaft 106 is provided with a drive pinion 108, which is a drive small gear for final reduction, on one end side, and a threaded portion 112, into which a tightening naso I-110, which is a fastener, is screwed on the other end side. . The drive shaft 106 is provided in the differential carrier 104 so as to be supported by a first tapered roller bearing 114 for the drive shaft and a second tapered roller bearing 116 for the drive shaft.

The first tapered roller bearing 114 has a first inner ring 120 that is externally fitted into a first external fitting part 118 on one end side of the drive shaft 106.
, a first outer ring 124 that is fitted into the first fitting part 122 of the differential carrier 104, and a first tapered roller 126 that is engaged and held between the first inner ring 120 and the first outer ring 124. . The second tapered roller bearing 116 also includes a second inner ring 130 that is externally fitted into a second external fitting part 128 on the other end side of the drive shaft 106, and a second inner ring 130 that is fitted into a second external fitting part 132 of the differential carrier 104. The second outer ring 134 and the second tapered roller 136 are fitted and held between the second inner ring 130 and the second outer ring 134.

A spacer 138 is interposed between the first inner ring 120 of the first tapered roller bearing 114 and the second inner ring 130 of the second tapered roller bearing 116.

Furthermore, between the drive pinion 108 and the first inner ring 120 of the first tapered roller bearing 114, there is provided a shim 1 for tooth contact adjustment.
40 is interposed.

As a method for selecting such a shim,
There is something disclosed in Publication No. 5. What is disclosed in this publication is the appropriate thickness of the left and right shims interposed between the left and right taber roller bearings and the differential carrier, which are disposed at both ends of the ring gear, which is a driven large gear for final reduction that meshes with the drive pinion. A suitable selection method is disclosed.

In addition, in the differential device 1O2 shown in FIG. 6, the other end side of the drive shaft 106 and the propulsion shaft (not shown)
A viscous coupling 142, which is a fluid coupling that functions as a differential limiting mechanism that allows differential movement and limits differential movement above a certain level, is interposed between the two. This viscous coupling 142 has a spline 144 on the joint side.
A sleeve spline 148 of a switching sleeve 146 is engaged with the switching sleeve 146 so as to be movable in the axial direction. This axial movement of the switching sleeve 146 engages or disengages the sleeve spline 148 with the drive shaft side spline 152 of the switching dock 150, so that the driving force from the propulsion shaft is transferred via the viscous coupling 142. The signal is transmitted to the drive shaft 106 or cut off.

[Problem that the invention seeks to solve]

By the way, when assembling the drive shaft 106 to the differential carrier 104 of the differential device 102, conventionally, first, the first outer ring 124 of the first tapered roller bearing 114 is assembled.
is fitted into the first fitting part 122 of the differential carrier 104, and the second outer ring 134 of the second tapered roller bearing 116 is fitted into the second fitting part 132 of the differential carrier 104. Also, a shim 140 for tooth contact adjustment is fitted onto the other end of the drive shaft 106, and then the first inner ring 120 of the first tapered roller bearing 114 is inserted into one end of the drive shaft 106. It is externally fitted into the first external fitting part 118 on the side.

Next, the first outer ring 124 fitted to the differential carrier 104
Insert the other end side of the drive shaft 106 from the side, and insert the first inner ring 1
The first tapered roller 126 held by the first outer ring 12
4. A spacer 138 is fitted onto the other end of the drive shaft 106 inserted into the differential carrier 104, and then the second inner ring 130 of the second tapered roller bearing 116 is fitted onto the second outer fitting portion on the other end of the drive shaft 106. 128, the spacer 138 is interposed between the second inner ring 120, and the second tapered roller 136 is held by the second inner ring 130.
is engaged with the second outer ring 134. Note that the spacer 138
can also be fitted onto the first inner ring 120 from the other end of the drive shaft 106 before inserting the drive shaft 106 into the differential carrier 104.

Thereafter, in the differential device 1O2 shown in FIG.
50, and then the tightening nut 110 is screwed onto the threaded portion 112 on the other end side of the drive shaft 106. This tightening nut 110 is assembled by tightening it so that the rotation starting torque of the drive pinion 108 reaches a set value. As a result, the spacer 138 interposed between the first inner ring 120 and the second inner ring 130 is deformed, and a preload is applied to the first tapered roller bearing 114 and the second tapered roller bearing 116.

However, when assembled in this manner, the spacer 138 may further deform after actual running, and the preload applied to the first tapered roller bearing 114 and the second tapered roller bearing 116 may be released. As a result, drive pinion 1
There was a disadvantage that the rotation starting torque of 08 was lost and the tooth contact noise, so-called clatter noise, increased.

In this case, although it is possible to provide a high rotational starting torque in anticipation of the preload being released after actual driving, there is a problem in that torque management is difficult.

[Purpose of the invention]

Therefore, an object of the present invention is to prevent the preload applied to the first tapered roller bearing for the drive shaft and the second tapered roller bearing for the drive shaft from being released after actual driving. An object of the present invention is to realize a method for assembling a differential device that can suppress an increase in tooth contact noise.

[Means for solving problems]

In order to achieve this object, the present invention provides a drive shaft for final reduction, which is provided with a drive small gear for final reduction on one end side and a threaded portion into which a fastener is screwed on the other end. A first tapered roller bearing and a second tapered roller bearing for the drive shaft are provided to be pivotally supported on the differential carrier, and a spacer is interposed between the first inner ring and the second inner ring of the first tapered roller bearing and the second tapered roller bearing, respectively. In the method for assembling a differential device, the differential device is assembled by screwing a fastener onto the threaded portion and tightening the screw so that the rotation starting torque of the driving small gear reaches a set value. When screwing together and tightening, a predetermined load is applied to the drive shaft from the final reduction drive pinion at one end toward the threaded portion at the other end, and the rotation starting torque of the drive pinion is set. The present invention is characterized in that the assembly is performed by screwing a fastener onto the threaded portion and tightening the screw portion so that the screw portion reaches the desired value.

[Effect]

According to the configuration of the present invention, when the fastener is screwed onto the screw portion on the other end side of the final reduction drive shaft and tightened, the screw portion is attached to the drive shaft from the final reduction drive small gear side on one end side to the other end side. While applying a predetermined load to the threaded part of the screw part, the screw is screwed into the threaded part and tightened so that the rotation starting torque of the small drive gear reaches the set value. Therefore, at the time of assembly, a preload can be applied to the first tapered roller bearing and the second tapered roller bearing with the load that acts on the drive small gear during actual running being incorporated in advance.

〔Example〕

Next, embodiments of the present invention will be described in detail based on the drawings.

1 to 5 show embodiments of this invention. In FIG. 5, 2 is a differential device, 4 is a differential carrier, and 6 is a drive shaft which is a drive shaft for final reduction. The drive shaft 6 is provided with a drive pinion 8, which is a drive small gear for final reduction, on one end side, and a threaded portion 12, into which a tightening tool IO, which is a fastener, is screwed, on the other end side.

This drive shaft 6 has a first tapered roller bearing 14 for the drive shaft and a second tapered roller bearing 16 for the drive shaft in the differential carrier 4.
It is supported by a shaft.

The first tapered roller bearing 14 includes a first inner ring 20 that is externally fitted into a first external fitting part 18 on one end side of the drive shaft 6, and a first outer ring that is fitted into a first fitting part 22 of the differential carrier 4. 24, and a first tapered roller 26 that is engaged and held between the first inner ring 20 and the first outer ring 24. Also,
The second tapered roller bearing 16 includes a second inner ring 30 that is externally fitted into a second external fitting part 28 on the other end side of the drive shaft 6, and a second outer ring that is fitted into a second fitting part 32 of the differential carrier 4. 34, and a second tapered roller 36 that is held and held between the second inner ring 30 and the second outer ring 34.

A spacer 38 is provided between the first inner ring 20 of the first tapered roller bearing 14 and the second inner ring 30 of the second tapered roller bearing 16.
It is provided by intervening. Furthermore, a shim 4o for tooth contact adjustment is interposed between the drive pinion 8 and the first inner ring 20 of the first tapered roller bearing 14.

A drive pinion 8 provided at one end of the drive shaft 6 meshes with a ring gear P, which is a large driven gear for deceleration. The ring gear 42 is fixed to the differential housing 44. The differential housing 44 is pivotally supported by the differential carrier 4 by a first cylindrical roller bearing 46A for the differential housing and a second cylindrical roller bearing 46B for the differential housing, and also includes first and second differential pinions 48A and 4.
8B and first and second differential side gears 50A and 50B that mesh with the first and second differential pinions 48A and 48B. This first and second differential side gear 50A.5
0B is connected to one end side of the left and right axles 52A and 52B, respectively. Note that 54A and 54B are left and right axle housings, respectively, and 56 is a differential cover.

In the differential device 2 shown in FIG. 5, a fluid is provided between the other end of the drive shaft 6 and the propulsion shaft 58, which functions as a differential limiting mechanism that allows differential movement and limits differential movement above a certain level. A viscous coupling 60 serving as a joint is interposed therebetween.

This viscous coupling 60 produces a differential function by interfering with the fluid 68 sealed in the sealed space 66 between the inner shaft 62, the outer case 64, and the inner shaft 62 and the outer case 6/1. and an actuating member 70 that causes
A fluid coupling housing 7 connected to the differential carrier 4
It is located within 2. This viscous coupling 60
Lj is rotatably supported by a first bearing 74 on the inner periphery of one end of the inner shaft 62 to a protrusion 76 on the other end of the drive shaft 6, and the outer periphery of the other end of the inner shaft 62 and the other end of the outer case 64 are connected to each other. It is pivotally supported in the fluid coupling housing 72 by a second bearing 78 on the inner periphery of the side and a third bearing 80 on the outer periphery of the other end of the outer case 64 .

Further, the outer case 64 of the viscous coupling 60
, a joint side spline 82 is formed on the outer periphery of one end, and a switching sleeve 8 is attached to this joint side spline 82.
4 sleeve splines 86 are engaged so as to be movable in the axial direction. On the other hand, a switching dog 90 having a drive shaft-side spline 88 formed on its outer periphery is engaged with the other end of the drive shaft 6 by a spline. This switching dog 9
0 is fixed to the drive shaft 6 by the tightening nut 10. Further, a threaded portion 9 is provided on the other end side of the inner shaft 62.
2 is provided. This threaded portion 92 projects outward from the fluid coupling housing 72 , and a connecting flange portion 94 of the propulsion shaft 58 is fixedly provided with a fixing nut 96 .

Thereby, by moving the switching sleeve 84 in the axial direction and engaging or disengaging the sleeve spline 86 with the drive shaft side spline 88, the driving force from the propulsion shaft 58 is transferred via the viscous coupling 60. It is transmitted to the drive shaft 6 or cut off.

When the drive shaft 6 is assembled to the differential carrier 4 of such a differential device 2, the drive shaft 6 is assembled as shown in FIGS. 1 to 4.

First, as shown in FIG. 1, the first outer ring 24 of the first tapered roller bearing 14 is fitted into the first fitting part 22 of the differential carrier 4, and the second outer ring 34 of the second tapered roller bearing 16 is fitted into the differential carrier 4. It fits into the second fitting part 32 of. Further, as shown in FIG. 2, a shim 40 for tooth contact adjustment is externally fitted from the other end of the drive shaft 6, and then the first inner ring of the first tapered roller bearing 14 is fitted from the other end of the drive shaft 6. 20 is externally fitted into the first external fitting part 18 on one end side of the drive shaft 6.

Next, as shown in FIG. 3, the other end of the drive shaft 6 is inserted from the first outer ring 22 side fitted to the differential carrier 4, and the first tapered rollers 26 held by the first inner ring 20 are inserted into the first outer ring 22. to engage. A spacer 38 is fitted onto the other end of the drive shaft 6 inserted into the differential carrier 4, and the second inner ring 30 of the second tapered roller bearing 16 is fitted onto the second outer fitting portion 28 on the other end of the drive shaft 6. A spacer 38 is interposed between the first inner ring 20 and the second inner ring 20, and the second tapered rollers 36 held by the second inner ring 30 are engaged with the second outer ring 34.

Note that the spacer 38 connects the drive shaft 6 to the differential carrier 4.
before inserting the first inner ring 2 from the other end side of the drive shaft 6.
0 can also be fitted externally.

After that, as shown in FIG.
2, after fitting the switching dog 90 from the other end of the drive shaft 6, the threaded portion 1 on the other end of the drive shaft 6 is fitted.
Screw 10 into 2 and tighten. As a result, the spacer 38 interposed between the first inner ring 20 and the second inner ring 30 is deformed, and a preload is applied to the first tapered roller bearing 14 and the second tapered roller bearing 16.

At this time, when tightening this tightening nut 10, a predetermined value is applied to the drive shaft 6 from the drive pinion 8 side on one end side toward the threaded part 12 side on the other end side, as shown in the direction of arrow F in FIG. (for example, approximately 100,100 O). In this way, while applying a predetermined load to the drive shaft 6 from the drive pinion 8 side at one end toward the threaded portion 12 side at the other end, the drive pinion 8 Tighten the threaded part 12 so that the rotation starting torque reaches the set value.
Assemble the nuts by screwing them together and tightening them (=J, confirm that the rotation starting torque is at the set value, and then tighten.) Nut 10
are fixed by crimping 98.

Thereby, during assembly, a preload can be applied to the first tapered roller bearing 14 and the second tapered roller bearing 16 with the load that acts on the drive pinion 8 during actual running being incorporated in advance.

That is, since a load acts on the drive pinion 8 from the meshing part with the ring gear 42 during actual running, the gear specifications of the drive pinion 8 are adjusted so that this load acts in a direction away from the meshing part with the ring gear 42. It is set. This is because if the gear specifications of the drive pinion 8 are set so that this load acts in the opposite direction, the drive pinion 8 may be damaged. Therefore, the threaded part 12 can be tightened without applying a predetermined load to the drive shaft 6 from the drive pinion 8 side at one end toward the threaded part 12 side at the other end, as in the conventional case. When 10 is screwed together and tightened to assemble 1, there is a problem that the preload is released due to the above-mentioned load. In other words, during actual driving, a load as shown in the direction of arrow F is applied to the drive pinion 8 by the ring gear 42, causing distortion and deflection in the differential carrier 4, drive pinion 8, etc. For example, the preload is released and the state of engagement between the drive pinion 8 and the ring gear 42 changes, resulting in an increase in tooth contact noise.

Therefore, as described above, while applying a predetermined load to the drive shaft 6 from the drive pinion 8 side at one end toward the threaded portion 12 side at the other end, the rotation starting torque of the drive pinion 8 reaches the set value. When assembled by screwing and tightening the tightening nut 10 onto the threaded portion 12, the first tapered roller bearing 14 and the second tapered roller bearing 14 are assembled with the load acting on the drive pinion 8 during actual driving incorporated in advance. A preload can be applied to the roller bearing 16. In other words, by reproducing the state in which a load is applied and assembling the vehicle before actual driving, the assembly is assembled in a state in which the change in preload has already been absorbed prior to the change in preload after actual driving. Since the preload can be attached, it is possible to prevent the inconvenience of the applied preload being released.

Therefore, it is possible to prevent the inconvenience that the preload applied to the first tapered roller bearing 14 and the second tapered roller bearing 16 is released after actual running, and it is possible to suppress an increase in tooth contact noise.

Furthermore, since there is no need to apply a high rotation starting torque in anticipation of the preload being released after actual driving, torque management can be facilitated. It should be noted that if a predetermined load is applied to the drive shaft 6 while rotating the drive shaft 6, the reproducibility can be further improved and loss of preload after actual driving can be more reliably prevented, which is advantageous in practice. .

〔Effect of the invention〕

As described above, according to the present invention, when the fastener is screwed onto the threaded portion on the other end side of the final reduction drive shaft and tightened, the screw is attached to the drive shaft from the final reduction drive small gear side on one end side to the other end. Assembling is done by applying a predetermined load toward the side threaded part and screwing the fastener onto the threaded part so that the rotational starting torque of the driving pinion reaches the set value. At the time of installation, a preload can be applied to the first tapered roller bearing and the second tapered roller bearing with the load that acts on the driving small gear during actual running being incorporated in advance.

Therefore, it is possible to prevent the preload from being released after actual driving, and it is possible to suppress an increase in tooth contact noise.

Furthermore, there is no need to apply a high starting torque in anticipation of the preload being released after actual driving, and torque management can be facilitated.

[Brief explanation of drawings]

1 to 5 show embodiments of the present invention, FIGS. 1 to 4 are explanatory diagrams showing the order of the assembly method, and FIG. 5 is a sectional view of the differential device. FIG. 8 is a sectional view of a main part of a conventional differential device. In the figure, 2 is a differential device, 4 is a differential carrier, 6 is a drive shaft, 8 is a drive pinion, 10 is a tightening nut, 12 is a threaded portion, 14 is a first tapered roller bearing, 16 is a second tapered roller bearing, 20 is the first inner ring, 24 is the first outer ring, 26 is the first tapered roller, 30 is the second inner ring, 3
4 is a second outer ring, 936 is a second tapered roller, 38 is a spazer, and 42 is a ring gear.

Claims (1)

[Claims] 1. A final reduction drive shaft is provided with a final reduction drive pinion on one end and a threaded portion into which a fastener is screwed on the other end. This first
A spacer is interposed between the first inner ring and the second inner ring of the tapered roller bearing and the second tapered roller bearing, respectively, and a fastener is attached to the threaded portion so that the rotation starting torque of the drive pinion becomes a set value. In the method of assembling a differential device by screwing together and tightening, when a fastener is screwed into the threaded portion and tightened, the drive pin is attached to the drive shaft from the final reduction drive small gear side on one end side to the other end side. The assembly is carried out by screwing a fastener onto the threaded part and tightening it so that the rotation starting torque of the driving small gear reaches a set value while applying a predetermined load toward the threaded part of the gear. How to assemble a differential device.