JP2883062B2 - Differential gearing - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a torque distributing type differential gear for a motor vehicle having a planetary gear train provided in a housing rotatable around a pair of drive axles and interconnecting the pair of axles. Related to the device.

[0002]

2. Description of the Related Art Generally, a differential gear device has a plurality of sets of planetary gears for connecting a pair of drive axles to a housing so as to be rotatable in opposite directions. The drive axle rotates about a common axis. The so-called side gear is fixed to inner ends of two drive axles so as to rotate integrally therewith, and serves as a sun gear of a planetary gear mechanism including a plurality of gears. The sun gears are interconnected by so-called element gears or coupling gears that make up each set of planetary gear elements. The planetary gears are variously eccentric with respect to a common axis of the sun gear and the drive axle, and are rotatably provided around an inclined axis. Normally, due to the relative relationship between the sun gear axis and the planet gear axis,
The types of gears constituting the planetary gear mechanism are determined. In the case of a parallel shaft, a spur gear or a helical gear is used. For example, U.S. Pat. No. 2,269,734 (Powel)
l); 2972265 (Walter); and 30
See No. 95761 (Hilado). on the other hand,
In the case of orthogonal axes, bevel gears or worm gears are used. That is, when the axis of the sun gear and the axis of the planetary gear intersect, a bevel gear is used, and when the axis of the gear does not intersect (as an example of this latter type,
See U.S. Patent No. 1,373,657 to Finefrock. ), A worm gear is used. The relative rotation (eg, differential) in the opposite direction between the drive axles is enabled by the entire planetary gear train in the planetary gear set, and the relative rotation in the opposite direction causes the two drive axles to rotate at different speeds. It has become possible. The torque transmitted to the drive axle via the inclined teeth of the sun gear is transmitted to a gear support end face in the differential gearing (such a support end face may include a journal formed in the housing, or (Which may be the end of the bore supported, or a special washer located between the end face of the gear or the end face of the gear and the housing). . The thrust, along with other loads transmitted by the meshing of the gears in the planetary gear train, create a frictional resistance that resists relative rotation between the drive axles. This frictional resistance is proportional to the torque acting on the housing. This proportional frictional resistance creates a torque difference between the two drive axles, preventing relative rotation of the drive axles until the bias ratio of the planetary gear train reaches a particular bias ratio.
Once the frictional resistance is defeated and the differential begins, the torque difference between the axles is distributed according to the bias ratio. A differential gearing that distributes torque at a substantially constant rate between relatively rotating drive axles is referred to as a torque distributing differential gearing. The ability to maintain a torque differential between the drive axles is a significant advantage in improving the traction of a vehicle. Normally, in a vehicle having a conventional differential gearing, when one drive wheel loses traction, the amount of torque distributed to the other drive wheel also decreases. However, when one drive wheel loses traction and a differential occurs between the two axles, the torque distribution differential gears distribute the increased torque to the drive wheel with better traction. In this case, the increased torque is determined by the bias characteristics of the differential gear. Various torque distribution differential gearing systems have been developed more than 75 years ago to allow vehicles to easily operate on the unpaved, muddy roads used to supply power during World War I. And these early ones have been improved several times since then. Some well-known planetary gear systems use planetary gear mechanisms with orthogonal axes (eg, the Fineflock patent), and other planetary gear systems use planetary gear mechanisms with parallel axes.
Examples of the latter type are Powell, Wal
In addition to the ter and Hillado patents, U.S. Pat. Nos. 1,195,314 (Williams), 200022
3 (Dupras), 2462000 (Randal)
l), and more recently, 3706239 (Mye
rs). In this latter differential gearing, rather than each gear being supported by a shaft received in a shaft bore,
It is supported by a pocket in the housing. Generally, gears used in a parallel shaft helical gear type planetary gear device are simpler to manufacture than gears used in an orthogonal shaft worm gear type torque distribution planetary gear device. However, when the latter is manufactured with the same number of sun gears and planetary gears as the former, the latter creates greater frictional resistance between the meshing of each gear and the support bearing. This, in turn, results in greater torque bias and / or increased control over the bias ratio. An important part of the torque bias of such orthogonal axis differential gears is the cumulative axial force (see below) produced by the sun gear and planetary gear when torque is acting on the differential gear. (Referred to as "edge thrust"). In contrast, such additive end thrust does not significantly contribute to the torque bias generated by the parallel shaft differential. That is, there are several basic designs of the torque distribution type parallel shaft differential gear device utilizing the frictional resistance generated by the end thrust, but in order to create a substantial part of the torque bias between the axles. In addition, it is not known to utilize the cumulative end thrust generated by both the sun and planet gears. For example, as the above basic design, Dupras, Po
There are U.S. Patents by well, Randall and Myers et al. In these basic prior arts,
Sun gears twisted in opposite directions mesh with one or more pairs of twisted-tooth planetary gears that mesh with each other. This design produces an end thrust on the sun gear, but the end thrust generated by the torsional teeth meshing with the sun gear uses the same direction of thrust used to interconnect the mating planetary gears. No end thrust is generated by a pair of planetary gears based on being resisted by the opposite end thrust generated by the helical teeth. A second basic parallel shaft differential gearing is Williams and Hill.
The torque distributing differential gearing disclosed in the ado patent is exemplified. In the second basic differential gear device, a pair of planetary gears mesh with each other by a torsion gear mechanism, and mesh with a sun gear by a spur gear mechanism. According to the gear train according to the prior art, end thrust is generated in the planetary coupling gear, but end thrust is not generated in the sun gear. There are other well-known parallel shaft torque distribution differential gearing.
In this known differential gearing, instead of assembling a pair of planetary gears, for example, U.S. Pat.
2 (Belansky), a gear that continuously meshes with each side gear over the entire circumference is assembled. In addition, Japanese Patent Application No.
No. 7346 discloses a parallel-shaft differential gear device of a spur gear in which each planetary gear has two gear portions, wherein a first gear portion of each planetary gear meshes with a planetary gear paired with it, and The second gear portion meshes with one sun gear and a pair of planetary gears. However, none of these suggests utilizing the additive end thrust generated by both the sun and planet gears to create a substantial portion of the torque bias. The present invention provides a simple improvement to such a parallel shaft torque distribution differential gearing that creates a greater torque bias between the interconnected axles, thereby substantially increasing the control over the bias ratio. To provide.

[0003]

SUMMARY OF THE INVENTION The present invention comprises an improved parallel shaft planetary gear train for use in a torque distribution type vehicle differential gearing. The sun gears of the differential gearing are each fixed to each end of a drive axle having a common shaft and are interconnected by at least one pair of planetary gears. Each of the paired coupling gears has two meshing portions. A first portion having torsional teeth meshing with the sun gear; and a second meshing portion meshing with the mating coupling gear. This second meshing part is designed as a spur gear or a helical gear twisted in opposite directions. The present invention provides a simple improvement in these meshes of each gear to provide a torque bias between the interconnected axles that is greater than that previously achieved in similar parallel shaft differentials. To provide. This additional torque bias is created by increasing the cumulative frictional resistance,
The cumulative frictional resistance is generated as a result of the end thrust generated by the various gear elements of the differential gearing. Each planetary gear is rotatably mounted in the housing about an axis parallel to the common axis of the axle, and further (a) is axially movable and contactable with at least one supporting end face; b) It is provided so as to be movable in the axial direction with respect to a paired planetary gear. That is, each planetary gear is axially movable in response to an end thrust generated by a gear mechanism that increases frictional resistance to relative rotation of the axle. The first meshing portion of each coupling gear has torsional teeth designed to generate an axial end thrust toward the support end surface when a torque is acting on the coupling gear. Furthermore, the second of each coupling gear
Are designed such that they do not generate any end thrust in the opposite direction to the end thrust generated by the first mesh. Therefore, each of the spiral tooth sun gears and the spiral gear planetary coupling gears generate end thrust whenever torque is being transmitted between the axles. And, this cumulative end thrust is not reduced by the reaction force acting on the meshing portion that interconnects each pair of coupling gears. That is, a simple improvement of the present invention to the planetary gear of the parallel shaft torque distribution differential gearing is that the combined end thrust generated by the planetary gear is at least equal to the end thrust generated by the sun gear. Thus, an improvement on the differential gearing, in some embodiments of the present invention, the end thrust generated by the planetary gears is greater than the end thrust generated by the sun gears. In the simplest embodiment of the present invention, the meshing region connecting the respective coupling gears, for example, the second meshing portion, is in the opposite direction to the spur gear or the torsion tooth forming the first meshing portion meshing with the sun gear. It is designed as a helical gear with a twist angle. With such a configuration, the torque distributed to the spiral tooth sun gear generates (a) an end thrust on each sun gear, and (b) an end thrust of the sun gear on the planetary coupling gear meshing with the sun gear. A reverse end thrust is generated. The differential gear device according to the present invention
Reducing the end thrust generated by the torsional teeth of the first meshing portion of each of the coupling gears, since the spur gears do not generate end thrusts if they include spur gears connecting the paired coupling gears. There is no. On the other hand, if the second meshing part of each coupling gear is designed with a twisting tooth opposite to that of the first meshing part, these teeth also generate end thrust. This additional end thrust is in the same direction as the end thrust generated by the torsional teeth of the first meshing portion. Therefore,
In this second design, each combined gear produces even greater end thrust, increasing the cumulative frictional resistance to create the desired torque bias between the axles. The present invention also provides a special gear in which the second meshing portion of each coupling gear, for example the portion meshing with a mating coupling gear, is divided into two separate and distinct meshing regions straddling the first meshing portion meshing with the sun gear. The special form of coupling gear (this particular form of planetary coupling gear is disclosed in co-filed US Pat. No. 5,122,101, rights holder; GordonBae
-Ji Tseng, title of invention; disclosed in Parallel Gear Coupled Gear Differential Gearing. ) Is also applicable to a parallel shaft differential gear mechanism. As described in the detailed description below, two embodiments of the present invention include such a straddle-type coupling gear. In each embodiment, the second meshing portion of each coupling gear has (a) teeth that do not generate any end thrust, and (b) the end thrust generated by the first meshing portion of the coupling gear. And a tooth that generates an end thrust in the same direction. Therefore, in both of these alternative embodiments, a significant part of the torque bias between the axles is that the frictional resistance generated as a result of the additive end thrust generated by the sun gear and each planetary gear set. Is based on Yet another embodiment is a multi-stage parallel shaft differential gearing (Sa
Ndro Guidoni et al. filed an application on June 10, 1991, entitled "Multi-Step Torque-Distributing Differential Gearing" and on March 24, 1992, Sandro Gui.
US Patent No. 5,098,356 to doni et al.
). In that,
When the torque conditions are different, a spring bias is used to selectively contact the sun gear and the coupling gear between the gears or between the gear and the supporting end face. For example, when the torque transmitted between the axle and the sun gear of this multi-stage differential gear device increases, the end thrust generated in the gear element overcomes the urging force of the spring, and the gears or the gear and the supporting end face are separated from each other. Contact. Thereby, the frictional resistance of the differential gear device against the relative rotation is increased. Thus, this type of differential gearing has a first torque bias characteristic for low torque conditions and a second stage bias for high torque conditions. In yet another embodiment disclosed herein, Guidoni and other types of differential gearing have been modified to increase the end thrust generated by the coupling gear. Such an increase in end thrust is achieved by a proper choice of the tooth design of the first and second meshes.

[0004]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIGS.
Two basic types of parallel axis differential referenced in the prior art
3 shows a planetary gear mechanism of the gear device. As shown in FIG.
Referring to the planetary gear mechanism, a pair of axles 10 and 12
The sun gears 14 and 16 are spline-connected
ing. The sun gear 14 has teeth 18 twisted to the right.
doing. On the other hand, the sun gear 16 is a tooth twisted to the left.
20. The sun gears 14 and 16 are a pair of planets
The first meshing portions 26, 28 of the coupling gears 22, 24 and the
Each is engaged. The coupling gear has a second meshing portion
30 and 32 respectively, and these second bites
The mating parts mesh with each other. In this prior art
Therefore, the first and second meshing portions of each coupling gear
Has a twist angle of That is, the first
The first meshing portion 26 is a rightward twist of the sun gear 14.
It has left-handed teeth that mesh with teeth 18 and
The second meshing portion of the gear 22 also has a left-hand twisting tooth.
doing. In contrast, the first meshing portion of the coupling gear 24
28 meshes with the left-handed helical tooth 20 of the sun gear 16
It has right-hand twisting teeth. Second of the coupling gear 24
Of the meshing portion 30 of the coupling gear 22
Right-handed teeth that mesh properly with left-handed teeth
Have. In the prior art shown in FIG.
The gear mechanism is a planetary gear of the prior art shown in FIG.
Similar to the mechanism, the sun gear and planetary gear
Reference numerals have been added. These two prior art planets
An important difference between the gear mechanisms is the setting of the teeth on each of those gears.
In total. That is, both sun gears 14 'and 16'
Have straight teeth 18 ', 20', respectively,
Are straight teeth 26 ', 28' of the coupling gears 22 ', 24'.
And each are engaged. Connecting the coupling gears to each other
Meshing portions 30 ', 32' used for
Is the left-handed and right-handed intermeshing teeth
And teeth. 2 (A) and 2 (B)
For reference, these are shown in FIGS. 1 (A) and (B).
Edges generated by prior art planetary gear mechanisms
4 schematically illustrates partial thrust. These schematics
, The sun gear has two common axes for simplicity.
Are separated. The sun gear 14, 14 '
The sun gears 16, 16 'are shown at the bottom of each figure.
Section. 2 (A) and 2 (B)
Is similar to the other schematic thrust diagrams shown in FIGS. 2, 4 and 5.
In addition, (a) the differential gear device is driven
Separated. ), The car depends on its engine
(B) the torque is between two axles
Sun gear distributed with small reference numbers
To the clockwise direction from the left side of the figure.
It is assumed that the clock is working. As well
The term "end thrust" is used in the following description and claims.
When used, the axial direction resulting from the torsion angle of the gear
It only means force in the direction. That is, the term
Based on meshing friction, slight assembly error in the axial direction, etc.
Neglecting the smaller axial thrust generated.
You. Furthermore, it is easy to understand the definition of the end thrust in the thrust diagram.
Drive helical gear so that it can be solved
Table showing the direction of the end thrust acting on the helical gear
1 (1962, published by McGraw-Hill Book Company
Edition, Gear Handbook for Darle WDudley Editing
(Quoted from). Table 1Direction of end thrust acting on drive gear and driven gear Torsion direction Rotation direction Drive gear Driven gear Left Clockwise Direction toward the viewer Direction away from the viewer Counterclockwise direction Direction away from the viewer Direction toward the viewer Right clockwise Direction away from the viewer Direction toward the viewer Counterclockwise direction Direction toward the viewer From the viewer The direction of separation, therefore, of the prior art play schematically illustrated in FIG.
In the schematic diagram of the star gear mechanism, the gear 14 has a gear 16
More torque is acting, gear 14 is driving
A gear, and the gear 16 is a driven gear
Is assumed. Similarly, the gear 14 has a clockwise
It is assumed that Luke is working. Twisted tooth 1
Considering the rightward twist of 8, the gear 14 is outlined
An end thrust in the direction indicated by arrow 34 is generated. Gear 14
With the left-hand twisting tooth of the first meshing portion 26 of the gear 22
Since the gears are meshed and driven to rotate counterclockwise, the gear 2
2 has an end thrust acting in the direction indicated by the black arrow 36.
You. Also for the left helix teeth of the second meshing part 30 of the gear 22
A counterclockwise torque acts, but the meshing part 30 is not
There is a relationship in which the teeth of the gear 24 are driven. As a result,
The end thrust in the direction shown by the black arrow 38 is applied to the
And the second meshing of the coupling gear 24
The right twisted tooth of the cut portion 32 is driven to rotate clockwise.
As a result, the hatching hatched on the connecting gear 24
An end-direction thrust indicated by the arrow 40 is generated. Coupling gear 24
Of the first engagement portion 28 of the right direction is a sun tooth
The leftward twisting teeth 20 of the wheel 16 are rotationally driven. This bite
The coupling gear 24 and the sun gear 16
End thrust in the direction indicated by the chining arrow 42 and the outlined arrow 44
Respectively occur. Therefore, FIG. 1 (A) and FIG.
The prior art planetary gear mechanism shown in FIG.
4 and 16 to generate end thrust, but with two combined gears
The end thrusts generated are in opposite directions
Are black arrows 36, 38 and hatched arrows 40, 4
You can see from 2. Therefore, by these planetary gears
The end thrust generated has no effect.
Absent. FIG. 2B shows the prior art planet shown in FIG.
FIG. 4 is a schematic thrust diagram relating to a gear mechanism, and its planetary gear;
In the mechanism, sun gears 14 ', 16' and connecting teeth
The first engagement portions 26 ', 28' of the wheels 22 ', 24'
Has teeth. Therefore, transmitted by sun gear 14 '
The driving torque is applied to the gear 14 ′ and the coupling gear 22.
No end thrust is generated in any of the driven parts. But
However, the counterclockwise torque acting on the coupling gear 22 'is reduced.
Of the engagement portion 30 'of the gear 22' in the leftward direction.
The teeth rotate the meshing portion 32 'of the gear 24' clockwise.
As a result, the black arrow 38 'and the hatched arrow 4
An end thrust indicated by 0 'is generated. In addition, sun gear 1
The meshing of the straight tooth 6 'with the meshing portion 28' of the coupling gear 24 '.
The engagement does not create any end thrust. That
As a result, in this prior art planetary gear mechanism, the sun gear is at the end.
Instead of producing thrust, each planetary gear is identified above
End thrust. From FIGS. 2A and 2B
As can be seen, two basic prior art planetary gear mechanisms
Is the critical end to either the sun gear or the planetary gear
Generates thrust, but ends at both sun and planet gears
Partial thrust is not generated cumulatively. But
It is precisely this invention that gives rise to
End thrust. FIGS. 1 (C) and (D) show this
A simplified embodiment of the invention has been disclosed. Its implementation
The example is similar to the prior art planetary gear mechanism described above, but with multiple
Has a number of improvements. Provided by its improvement
The planetary gear mechanism of the present invention increases the frictional resistance and
More to increase the characteristic bias of gearing
End thrust. Embodiment of the present invention shown in FIG.
In the example, a pair of sun gears 15, 17 are opposite to each other
It has twisted teeth twisted in the direction. These gears
Is a first meshing portion of the pair of planetary coupling gears 23, 25.
27 and 29, respectively, and a pair of planetary gears
Is determined by the engagement of the straight teeth of the second engagement portions 31 and 33.
Are interconnected. The end thrust resulting from this gear train
The force is shown in FIG. Prior art planetary gearing
Apply the same assumptions used above for the analysis of
If the sun gear 15 twisted clockwise,
Torque acts on the driven gear of the coupling gear 23.
While applying a counterclockwise torque to the portion 27,
Ends indicated by pullout arrow 35 and black arrow 37
Thrust is applied to each gear. Coupling gear 25
The engagement portion 33 is formed from the engagement portion 31 of the coupling gear 23.
Rotated clockwise by counterclockwise torque
However, these straight gears produce any end thrust.
Absent. However, the right direction of the driving gear 25
Meshing part 29 which is twisted to the outside and sun gear 17 which is the driven side
Meshing with the left helical tooth of each gear
The arrow indicated by the chining arrow 43 and the white arrow 45
Generate force. As shown by each arrow in FIG.
In the embodiment shown in FIG. 1C, both sun gears and both
End thrust is generated between the planetary gears. in this way,
The combination of gear teeth is shown in FIG.
It can be changed relatively easily compared to the star gear mechanism.
However, the frictional resistance in the planetary gear mechanism has been considerably increased.
Can be The embodiment shown in FIG.
15 'and 17' are right-hand twist teeth and left-hand twist teeth, respectively.
Helical teeth, each of which has a coupling gear 23 ',
25 'twisted to the left and 27' to the right
1 at the point of engagement with the twisted engagement 29 '.
This is the same as that shown in FIG. However, straight teeth
Therefore, instead of being connected to each other, the second
Meshing portion 31 'has right-hand twisted teeth.
Meshing of the coupling gear 25 'with a left-hand twisting tooth
And is engaged with the notch 33 '. Schematic shown in FIG. 2 (D)
As can be seen from the thrust diagram, the sun gear 15 'as the driving side
And the meshing portion 27 'of the driven gear 23'.
The connection is similar to that of the first embodiment of the present invention shown in FIG.
End thrust (arrow 35 ')
And an arrow 37 '. ). Also,
The meshing part 29 'of the gear 25' and the sun gear 17 '
Between the gears are indicated by arrows 43 'and 4
A similar end thrust is produced as indicated at 5 '. However
However, in this embodiment, the right and
Second meshing portions 3 each having leftward twist teeth
1 ', 33' additional arrows indicated by arrows 39 ', 41'
Generates end thrust. Both meshing portions of the coupling gear 23 '
27 ′, 31 ′ (arrows)
(Indicated by marks 37 'and 39') are in the same direction.
Support formed on gear 23 'and housing (not shown)
There is considerable additional friction between the end faces. same
Similarly, the two meshing portions 29 ', 33' of the coupling gear 25 '
Therefore, the end thrust generated (hatched arrow 4)
1 ′ and 43 ′) are in the same direction,
There is a considerable amount of frictional resistance between the wheel 25 'and its supporting end face.
Anti is added. (Note: Each planetary gear and each support
Such a relationship with the end surface is shown in FIG.
This can be best understood in the examples. This second embodiment according to the present invention will be described with reference to FIG.
Compared to a similar prior art planetary gear mechanism analyzed,
Embodiments of the present invention provide only relatively simple modifications.
While increasing the effective end thrust for differential gearing.
It is very clear that it will increase. As shown in FIG.
Reference is made to the planetary gear mechanism of the differential gearing. This figure is
The above-referenced co-filed U.S. patent application "Parallel Axis Coupling"
Planetary gear mechanism disclosed in "gear differential gearing"
FIG. 3 is a schematic diagram of a simple perspective view of FIG. This torque distribution difference
In a dynamic gear device, a sun gear 50 having a twisted tooth,
52 is mutually connected by a pair of planetary coupling gears 54 and 56.
Are combined. Each coupling gear is one of the sun gears and it
And each other in two separate meshing areas
Are engaged. This relationship is represented by the symbolic diagram shown in FIG.
Can best be understood. FIG. 4 (A)
It has been created for simplicity and
Means that the two sun gears 50 and 52 are at the top and bottom of the figure.
And the basic planetary gear train as shown in
It is shown spread out on a plane. Their common axis is shown in FIG.
Are separated as in the schematic diagram of FIG. FIG. 3 (A)
Referring to FIG. 4A and FIG.
Each has shaft ends 58 and 60, and each shaft end is paired.
Mesh with the opposite shaft end of the combined gear
I have. The opposite shaft end of each coupling gear has a long continuous mesh
Areas 62 and 64, and this continuous meshing area
Meshes with sun gears 50 and 52 and forms a pair
It is in mesh with the shaft ends 58 and 60 of the coupling gear. This tooth
Planetary gear train shown in FIGS. 1 (A) to 2 (D)
Shall be described in terms similar to those used in the description of the structure.
Then, the second meshing portions of the coupling gears 54 and 56 (the
The part meshing with each other) is the first gear meshing with the sun gear.
Separated into two separate areas that straddle the
You. Each long continuous meshing region 62, 64 is
The role of the first and second gears 54 and 56 as a first meshing portion;
Both roles as half of the second meshing part
Fulfill. This new gear train is described in the joint application above.
Is described in more detail, see the disclosure content of that application
Has been adopted as. The planetary gear shown in FIG.
In the mechanism, the long meshing portion 6 of each coupling gear
2, 64 and shaft ends 58, 60 are twisted in the same direction.
Has teeth. Both meshing portions of the coupling gear 54 are to the left
And the two meshing portions of the coupling gear 56
Have right-hand twisting teeth. FIG. 4A shows the sun
The torque by the gear 50 is transmitted to this planetary gear set.
It shows the edge thrust generated at times. Again, Table 1
And when viewing the planetary gear set from the left
It is assumed that a clockwise torque is acting on the gear 50.
Set. When the gear 50 is driven to rotate clockwise, white
An end thrust, indicated by arrow 66, results. Meanwhile, length
Of the long meshing portion 62 is driven to the left.
Then, an end thrust indicated by a black arrow 68 is generated.
At the same time, meshing engagement with the coupling gear 56 of the coupling gear 54
The end portion generates an end thrust indicated by black arrows 70 and 72.
Let Two separate sets of right-hand twisting teeth of the coupling gear 56
Is a shaded arrow 7 with a downward slant line when driven.
An end thrust indicated by 4,76 is generated. On the other hand, meshing
The rightward twisting tooth of the portion 64 is a shaded arrow 7 when driven.
An end thrust shown at 8 is generated. Sun gear 52 left direction
The twisted tooth of the end thrust shown by the white arrow 80 when driven
Cause. The total of these end thrusts is the sun gear 5
The frictional resistance between 0,52 is consequently increased. Only
And the end point indicated by the pair of black arrow and shade arrow
Because the forces are in opposite directions,
Even if the end thrust occurs even if it fits
Few. Next, FIG. 3B and FIG. 4B will be referred to.
Meanwhile, the planetary gear device shown in FIG.
This is an improvement. In this embodiment, both
The sun gears 50 'and 52' have right-hand twist teeth.
I have. On the other hand, the shaft end 5 of each of the planetary coupling gears 54 'and 56'
8 ', 60' are long engaging portions 62 ', 64'.
Have twisted teeth twisted in the opposite direction to the twisted teeth of
You. FIG. 3 (A) and FIG.
And the same torque as assumed in the description of FIG.
Assuming that the transmission conditions are applied, the sun gear 50 ',
52 'is the end in the direction shown by white arrows 66' and 80 '
Thrust is generated, and increased end thrust is generated on each connected gear
I do. That is, it is generated by the shaft ends 58 'and 60'.
End thrust to be tightened (black arrow 72 'and shaded arrow
74 ') responds to meshing with the sun gear
Of the main end thrust (black arrow 68 '
Rather than resisting the arrow 78 ').
It is rather a supplement. 3C and 4C are modified according to the present invention.
9 shows another improved planetary gear mechanism. Thick
The positive gears 51 and 53 are the first meshes of the coupling gears 55 and 57.
Rightward twisted teeth meshing with mating parts 63, 65 and leftward
, Respectively. Separation of each coupling gear
The second meshing portion, that is, the shaft end 5 of the gear 55
9, 59 'and the shaft ends 61, 61' of the gear 57 are
Each has a twisted tooth twisted in the same direction. this
In such a gear train, sun gears are indicated by white arrows 67, 8
As shown at 1, they are pushed closer together. one
On the other hand, the friction between each planetary coupling gear and each supporting end face
Resistance is indicated by a set of black and shaded arrows
Maximal due to cumulative end thrust. That is, the gear 5
The left twisting tooth of the first meshing portion 63 of No. 5 is a black arrow
The end thrust indicated by the mark 69 is generated, and the shaft end 5 serving as the driving side is generated.
9, 59 'rightward twist teeth are indicated by black arrows 71, 7
As shown at 3, an end thrust in the same direction is generated. same
Similarly, the leftward twisting of the shaft ends 61 and 61 'of the gear 57
The teeth are driven clockwise and shaded arrows 7
5 and 77 to produce end thrust. This end
Thrust is applied to the meshing part 65 twisted rightward as the drive side.
Therefore, the generated end thrust (shade arrow 79 indicates
Therefore, it is the same direction. To explain again,
Although the original planetary gear mechanism shown in FIG.
(Fig. 3 (B) and Fig. 3 (C))
Then, the end thrust related to the frictional resistance greatly increases
You can see that. Another embodiment of the present invention is schematically shown in FIG.
It is shown schematically. Each of this planetary gear mechanism shown
Such gears are mounted in a suitable housing. C
The aging is omitted in the previous figures for simplicity.
Each planetary gear mechanism supports various gears.
And provide similar supporting end faces
It has a housing. Proper supporting end faces should be
To create a torque bias for the torque distribution operation.
To generate the necessary frictional resistance. In FIG. 5, planetary teeth
The train is positioned 180 ° around the two sun gears
It has two pairs of coupled gears. This embodiment is based on Sa
filed by Ndro Guidoni et al.
Improvement of the basic structure disclosed in the co-pending U.S. patent application
It is. A housing is provided at each end of the axles 110, 112.
A pair of sun gears with the axes aligned within 115
114 and 116 are supported. With the other embodiments above
Similarly, each pair of planetary coupling gears
And mesh with one of the sun gears. Coupling gear 122
Is the leftward gear that meshes with the rightward twisted tooth of the sun gear
A first meshing portion 126 having teeth, and
Meshes with the second meshing portion 132 of the coupling gear 124
Having a second meshing portion 130 (note; one of each pair
Are only shown in this schematic diagram. ). Join
The first meshing portion 128 of the gear 124 is connected to the sun gear 11
Has right-handed teeth that mesh with left-handed teeth of No.6
doing. In this planetary gear mechanism, the sun gear 11
The bush 141 and the bush 141
143 are provided, and the sun gears 114 and 1 are provided.
16 was supported by the bushes 141 and 143, respectively.
A support plate 140 and a flat spring (Belleville spring) 142
Springs are biased away from each other.
You. The planetary coupling gears 122 and 124 each have a shaft 14
4, 146, each shaft 144, 146,
Flat spring ball support elements 156a, 156b, 156
c, 156d, the bearing holes 148, 150, 152,
154 are urged away from the respective bottom surfaces. Spring
The biasing force generated by element 156 is such that the differential gear mechanism is low.
When in the torque state, each end of the coupling gears 122, 124
Surface away from the supporting end faces 158, 160, 162, 164
Is enough to keep. Assuming the same as above,
That is, the torque is transmitted from the left sun gear 114 to the differential gear device.
To the right sun gear 116 through the
The torque acts clockwise when viewed from the perspective of the sun gear 114
The right-hand twisting edge of the edge indicated by the outlined arrow 166
It is assumed that a partial thrust is generated. Of the coupling gear 122
The left twisting teeth of the first meshing portion 126 are blackened.
End acting in the opposite direction as indicated by arrow 168
Generate thrust. Second meshing portion 13 of gear 122
0 rotationally drives the left-hand twisting tooth of the coupling gear 124
It has right-hand twisting teeth and is marked with a black arrow 170.
End acting in the direction indicated by the arrow 172, respectively.
A thrust is generated on the gears 122 and 124. Coupling gear 12
The first meshing portion 128 of FIG.
Has and drives the leftward twisting tooth of the sun gear 116
In a relationship. So that the shade arrow 174 and white
The end thrust acting in the direction indicated by the extraction arrow 176 is applied to each tooth.
Each in the car. Raw on sun gear 114, 116
End thrusts facing each other, high torque condition
Below, these thrusts are relatively small
Sun gear bush 141,1
43 to make the end faces 145, 147
And thereby increase the frictional resistance between them
I understand. Similarly, the two meshing portions of the coupling gear 122
The end thrusts generated by the
These forces are applied to a spring element provided at the end of the bearing bore 148.
Overcoming the biasing force of 156a, the left end face of the gear 122 is
It is sufficient to make contact with the supporting end surface 158. Coupling gear
Both end thrusts generated by 124
The same direction, but occurs in the paired coupling gear 122
In the opposite direction to thrust. Coupling acting on gear 124
The end thrust is applied to a spring provided at the end of the bearing hole 154.
Overcome the bias of element 156d, thereby
24 is brought into contact with the supporting end surface 164. Gear 12
2, 124 and respective supporting end surfaces 158, 16
4 and the torque is transmitted between the axles
Whenever, the frictional resistance of this differential gearing embodiment,
In other words, the torque bias is increased considerably. As mentioned above, the car is driven forward by its engine
When viewed from the left side of the figure,
A larger clockwise torque acts on the sun gear
Tentatively, the torque is distributed between the two axles.
Is defined. If instead, the other sun gear
Even if large torque is applied, the car
If it is driven forward by the gin,
End thrusts indicated by various arrows of 5 and 5 remain the same
It should be noted that For example, FIG.
, The torque is transmitted from the sun gear 116
If so, the left-handed tooth is also clockwise (left or right
When viewed from above), which is white
End thrust in the direction indicated by pullout arrow 176 will occur
U. Similarly, to the right of the first meshing portion of the coupling gear 124
Torsional teeth will be driven to rotate counterclockwise
So that the shaded arrow 174 and other directions indicate
End thrust will occur. On the other hand, cars go down the slope
Coast mode (as different from drive mode)
Mode), the drive torque acting on the sun gear
Is oriented in a counterclockwise direction, and each of FIGS.
The end thrusts indicated by the seed arrows are all reversed. It
Therefore, referring again to the embodiment shown in FIG.
And the engine is exerting the braking effect
Occasionally, differential gears are acted upon by torque in the opposite direction
And thus the end generated by all gears
Thrust is reversed. This embodiment of the present invention also
Provides a multi-stage bias characteristic in coastal conditions such as
You. The sun gears 114 and 116 are connected to the outer end faces 18 of the gears.
2,184 and washer 186,188
White arrows 166, 17
6 is slightly biased. Low torque coating
In the strike state, the force of the springs 178, 180
Enough to hold the gears 114, 116 in the position shown in FIG.
It is. However, in coast mode,
When high torque is acting, the torsion teeth of each gear
Therefore, the end thrust generated (open arrow 166,
176), which is opposite to the direction indicated by 176)
Overcome the bias of 178,180. And it
The respective hubs 190 and 192 are connected to the support ends of the housing 115.
Contacting the surfaces 194 and 196 to increase the frictional resistance of the device
Let Similarly, in the coast state, the coupling gear 12
The end thrust acting on 2,124 is reversed,
Cars are marked with black arrows 168, 170 and shade arrows 172,
Move in the direction opposite to the direction indicated by 174.
You. Therefore, in the high torque coast state, each coupling gear
The end thrust generated by the spring 156b, 1
56c, the right side of the gear 122
The end face is moved until it contacts the support end face 160, and the gear 1
24 is moved until the left end face contacts the support end face 162
Let it. Of course, the differential gear device shown in FIG.
, The biasing force of each spring element is
Keep the end faces out of contact with each other and / or each tooth
Maintain a non-contact state between the end face of the vehicle and the support end face. in addition
In such a low torque state, the differential gear device
To reduce the torque bias. However, this
By selecting gears according to the light, high torque
Torque bias of differential gearing in
Can be That is, if the planetary gear mechanism of FIG.
However, instead of such gears, the first and
And the second mating portion both have the same direction of twist angle
Conventional gear train (see the prior art planetary gear train shown in FIGS. 1A and 1B).
Gears), each planet
The thrust acting on the coupling gear will be in the opposite direction,
The contact between these gears and the supporting end face
The generated frictional resistance will be reduced. Therefore, this departure
Ming is the torque of most parallel shaft torque distribution differential gearing
Used to determine and control bias characteristics
It can be used to greatly increase end thrust.

[Brief description of the drawings]

1A and 1B are perspective schematic views of a simplified planetary gear mechanism according to two basic designs of a conventional parallel shaft torque distribution differential gearing; 1
(C) and (D) are similar views of two differential gear trains improved in accordance with the present invention.

FIG. 2A, FIG. 2B, FIG. 2C and FIG.
FIG. 3 is a schematic diagram relating to the planetary gear mechanisms shown in FIGS. 1 (A), (B), (C) and (D), respectively, and shows the direction of the end thrust acting on each planetary gear mechanism under the same torque condition. Is shown.

3 (A) is a perspective schematic view of a simplified planetary gear mechanism according to another design of the parallel shaft torque distribution differential gear device, and FIG. 3 (B), (B). C) is a similar view of a differential gearing improved according to the invention.

4 (A), (B) and (C) are schematic diagrams respectively relating to the planetary gear mechanism shown in FIGS. 3 (A), (B) and (C), and show the same torque. The direction of the thrust acting on each planetary gear mechanism under the state is shown.

FIG. 5 is a schematic cross-sectional view of a portion of yet another example of a parallel shaft torque distribution differential gear device improved in accordance with the present invention.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-38733 (JP, A) JP-A-5-280597 (JP, A) JP-A-63-76938 (JP, A) JP-A-60-1985 175843 (JP, A) JP-A-49-104328 (JP, A) JP-A-48-78369 (JP, A) JP-A-59-97346 (JP, A) JP-B-46-3407 (JP, B1) (58) Field surveyed (Int. Cl. ⁶ , DB name) F16H 48/20

Claims (10)

(57) [Claims] 1. A differential gear device for distributing torque between a pair of relatively rotating axles with a predetermined torque bias, wherein the differential gear device is rotatable around a pair of axles (10, 12) sharing a common shaft. A pair of sun gears (50, 52) rotatably provided in the housing and supporting each end of the axle; (5)
(53), and at least one pair of planetary coupling gears (54, 56) and (55, 57) rotatably provided in the housing about an axis parallel to the common axis. A first gear portion (62, 64) meshing with one of the sun gears; (63, 65) and a second gear portion (58, 60) meshing with a paired coupling gear;
9, 61), wherein the meshing of the sun gear and the coupling gear mutually connects the respective ends of the pair of axles in a mutually driving relationship. 52); (51, 53) having twisting teeth of opposite directions and arranged in the housing, and each coupling gear (54, 56) in each pair;
7) is the first gear portion (62, 6) having twisted teeth.
4) having (63, 65) and within said housing (a) at least one supporting end surface (1a, 1b) and in contact with each other; and (b)
The sun gear (50, 52) is provided so as to be movable in the axial direction with respect to the paired coupling gear, based on the reverse twist angle when the axle is driven forward.
The end faces of (1,53) are pressed against each other in the axial direction, and the pair of coupling gears (54,56);
7) are respectively pressed by the supporting end faces (1a or 1b) to control the torque bias of the differential gear device between the end faces of the pair of sun gears and between the pair of coupling gears and the supporting end face. The torsional directions of the torsional teeth of the sun gear and the coupling gear are selected so as to generate frictional resistance, and the first coupling gear (56,
57), the first and second gear portions (64, 60; 65,
61) is a sun gear (5) meshing with a pair of coupling gears.
(5) A differential gear device characterized by being separated by a non-meshing portion straddling (0, 51). 2. The combination gears (54, 5) in each pair.
6); the first gear portion (62, 64) of (55, 57);
(63, 65) and a second gear portion (58, 60);
(59, 61) are separated by a non-meshing portion straddling the sun gear (50, 52); (51, 53) meshing with the paired coupling gear, and the paired coupling gear (5
4. The differential gear device according to claim 1, wherein (55, 57) mesh with each other at two separation regions straddling a portion meshing with the sun gear. 3. The first gear portion of each pair of coupling gears.
64) have teeth twisted in opposite directions, and the separated first and second gear portions (64, 60) of the first coupling gear (56) have twisted teeth in the same direction. 2. The differential gear set of claim 1, wherein 4. Each pair of coupling gears (54, 56);
5. The differential gear according to claim 2, wherein (5, 57) has meshing teeth twisted in the opposite direction to the teeth of each sun gear. 5. A pair of coupling gears (54, 56);
5, 57) mesh with the two separation regions (58, 6).
2: 60; 64); (59,59 ';61,61')
3. The differential gear device according to claim 2, wherein the gears are arranged near both ends in the axial direction of each coupling gear. 6. A meshing region of the coupling gear (54) paired with one coupling gear (56) of the pair of coupling gears with the sun gear (50) and the one coupling gear (56). 2. The differential gear set of claim 1, wherein (62) is continuous. 7. A meshing region of the pair of coupling gears (55) with the coupling gear (57) and the sun gear (51) is divided into two separate regions (59 ', 63),
2. The differential gear set according to claim 1, wherein said two separate regions each have a gear portion. 8. The differential gear set of claim 2, wherein one of said separation regions in which each pair of coupling gears meshes is continuous with a region in which said coupling gear meshes with a sun gear. . 9. A space region forming a gap to prevent the continuous meshing region (62) of the coupling gear (54) from coming into contact with the sun gear (52) meshing with the mating coupling gear (56), 9. The differential gear set of claim 8, wherein said differential section is separated from other areas (58) meshing with said mating coupling gear (56). 10. A region of the coupling gear (55) meshing with the paired coupling gear (57) and the sun gear (51) is divided into two separate regions (59 ', 63), The two separate areas each have a gear section, and the coupling gear (55) is paired with the coupling gear (5).
7) the two separate areas (59, 59 ') meshing with
10. The differential gearing of claim 9 wherein the gears have twisting teeth in similar directions.