JP3219979B2 - Differential device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a differential device for a vehicle.

[0002]

2. Description of the Related Art FIG.
Such a differential device 501 is described. In the differential device 501, the driving force of the engine that rotates the differential case 503 including the case body 503a and the covers 503b and 503c is transmitted from the first and second pinion gears 505 and 507 to the wheels via left and right side gears 509 and 511. Is done. First and second
Pinion gears 505 and 507 and left and right side gears 5
09 and 511 are constituted by spur gears. The pinion gears 505 and 507 are slidably and rotatably housed in housing holes 513 and 515 of a case body 503a of the differential case 503, respectively.

[0003] The pinion gears 505 and 507 are driven by side gears 509 and
511 and the pinion gear 50
5, 507 are engaged with each other,
13, 515 are pressed against the wall surface and rotate while rubbing. A differential limiting force is obtained by this frictional resistance.

Japanese Patent Laid-Open Publication No. Sho 60-175843 discloses a differential device 601 as shown in FIG. In this differential device 601,
The driving force of the engine for rotating the differential case 603 is transmitted from the pinion gears 605 and 607 to the output side gear 60.
It is transmitted to the wheels via 9, 611. Pinion gear 6
05 and 607 are storage holes 613 and 6 of the differential case 603.
15 are slidably and rotatably accommodated. The pinion gears 605 and 607 and the side gears 609 and 611 are each formed by a helical gear. An opening 61 for introducing oil is provided on the side wall of the differential case 603.
9 are formed.

While transmitting torque, the pinion gear 6
05 and 607 are pressed against the wall surfaces of the storage holes 613 and 615 by a meshing reaction force with the side gears 609 and 611 to generate frictional resistance, and the meshing thrust force of the helical gear causes a gap between the side gears 609 and 611,
Each gear 605, 607, 609, 611 and differential case 6
03, frictional resistance is generated, and a differential limiting force is obtained by these frictional resistances.

Further, Japanese Patent Application Laid-Open No. 6-323373 discloses that
A differential device as shown in FIGS. 10 and 11 is described. In this differential device 701,
Differential case 7 consisting of case body 702 and cover 703
The driving force of the engine that rotates the pinion 04 is a pinion gear 7 that is a set of a plurality (3 in this example) meshing with each other.
05, 707 (these pinion gears are another set of central pinion gears) to left and right side gears 709, 7
11 to the wheels. Pinion gear 705,
Reference numeral 707 is slidably and rotatably accommodated in accommodation holes 713 and 715 of the case main body 702 of the differential case 704. An opening 720 is provided on the outer peripheral wall of the case main body 702 of the differential case 704.

While transmitting the torque, the pinion gear 7
05 and 707 are pressed against the wall surfaces of the storage holes 713 and 715 due to the meshing reaction force with the side gears 709 and 711, and frictional resistance is generated. When each gear is a helical gear, the meshing thrust force causes the side gear 709 and
711, each gear 705, 707, 709, 711
Frictional resistance is generated between the differential case 704 and the differential case 704, and a differential limiting force is obtained by these frictional resistances.

[0008]

However, in the differential devices 501, 601 and 701 as described above, the frictional resistance between the side gear and the pinion gear according to the input torque and the differential case due to the meshing thrust force. And the differential limiting force is obtained, but the pinion gears 505, 507, 605, 607, 705,
707 and accommodation holes 513, 515, 613, 615, 71
In the sliding portions 3 and 715, if the oil is not sufficiently introduced into the differential case, the oil may run out, and seizure or galling may occur, causing a problem that the differential limiting function becomes unstable. Was.

[0009] In particular, like the differential devices 601 and 701 shown in FIGS.
611, 709, 711 and pinion gears 605, 60
When the helical gears 7, 705, and 707 are formed, the end face friction of the pinion gear and the side gear due to the thrust force greatly contributes to the differential limiting force. Therefore, lubrication of the end face is particularly necessary. Lubrication was insufficient only by introducing oil from the provided openings 619 and 720.

That is, the oil entering through the openings 619 and 720 is blown outward by centrifugal force to the rear, so that the lubricating effect on the sliding part between the side gear end face and the differential case and the sliding part between the pinion gear end face and the differential case is provided. Is small,
Problems such as burn-in and galling due to oil shortage occurred in those sliding portions, and the differential limiting function became unstable.

An object of the present invention is to provide a differential device in which a sliding portion between a side gear or a pinion gear and a differential case is sufficiently lubricated and a stable differential limiting function can be obtained.

[0012]

According to the first aspect of the present invention, there is provided a differential case which is disposed in an oil sump and is driven to rotate by an engine, and a pair of end surfaces each of which slides directly through a thrust washer or directly with the differential case. An output side gear, at least a pair of pinion gears arranged radially outside of the side gear and meshing with each other and separately meshing with the side gear, a storage hole formed in the differential case for slidably and rotatably storing the pinion gear, and an output coupled to the side gear. A first oil passage formed between the outer periphery of the output shaft and the inner periphery of the boss portion; a first oil passage formed between the differential case and the side gear; The other end communicates with the passage and the side gear
While communicating with the sliding part of the differential case,
The first communicating with the part facing the meshing part with the side gear
And two oil passages .

In this differential, the oil that has flowed from the oil reservoir into the first oil passage formed between the inner periphery of the boss portion of the differential case and the outer periphery of the output shaft by rotation of the differential case communicates with the first oil passage. The oil is supplied from one end of the second oil passage to the sliding portion between the side gear and the differential case at the other end, and is supplied to a portion facing the meshing portion between the pinion gear and the side gear. Therefore, lubrication between the sliding portion between the side gear and the differential case, the meshing portion between the pinion gear and the side gear, and the lubrication between the pinion gear and the housing hole are sufficient. Further, when the meshing rotation of the pinion gear and the side gear occurs, the pump action between these gears further promotes the supply of oil to the sliding portion between the side gear and the differential case, improving lubricity and preventing seizure. You.

[0014] The invention according to claim 2 is arranged in an oil sump.
And a differential case driven by the engine
Each end face can be de-assembled via a thrust washer or directly.
A pair of output side gears that slide with the case,
It is located on the outside of the gear in the radial direction and meshes with each other.
At least a pair of pinion gears meshing with side gears
And the pinion gear formed on the differential case is slidable and rotatable
And the output shaft connected to the side gear
The boss part of the differential case that penetrates, the outer periphery of the output shaft and the boss part
A first oil passage formed between the first oil passage and the inner periphery of the
One end formed between the base gear and the side gear has the first end.
The other end slides through the side gear and differential case
And the pinion gear mesh with each other
And a second oil passage communicating with a portion opposed to the second oil passage .

In this differential device, since the other end of the second oil passage communicates with a portion of the pinion gear opposed to the meshing portion, the inflowing oil is supplied to the sliding portion between the side gear and the differential case. It is supplied to a portion of the pinion gear that opposes the meshing portion.
Therefore, lubrication between the sliding portion between the side gear and the differential case and the meshing portion between the pinion gear and the pinion gear and the housing hole is sufficient, and the lubricity is improved.

The invention according to claim 3 is arranged in the oil sump.
And a differential case driven by the engine
Each end face can be de-assembled via a thrust washer or directly.
A pair of output side gears that slide with the case,
It is located on the outside of the gear in the radial direction and meshes with each other.
At least a pair of pinion gears meshing with side gears
And the pinion gear formed on the differential case is slidable and rotatable
And the output shaft connected to the side gear
The boss part of the differential case that penetrates, the outer periphery of the output shaft and the boss part
A first oil passage formed between the first oil passage and the inner periphery of the
Over scan said first tail end is formed between the Saidogi Ya
The other end communicates with the oil passage and the end face of the side gear and the differential case
To the sliding part of the pinion gear and to the end face of the pinion gear.
A second oil passage communicating with a sliding portion with the case.
Characterized in that was.

In this differential device, the other end of the second oil passage communicates with the end face of the side gear and the sliding portion of the differential case, and also communicates with the end face of the pinion gear and the sliding portion of the differential case. After being supplied to the sliding portion between the side gear end surface and the differential case, it is supplied to the sliding portion between the pinion gear end surface and the differential case. Therefore, the sliding portion between the side gear and the differential case and the sliding portion between the pinion gear and the differential case are sufficiently lubricated.

According to a fourth aspect of the present invention, in the differential device according to the third aspect, the other end of the second oil passage communicates with a portion facing the meshing portion between the pinion gears.

In this differential, since the other end of the second oil passage in claim 3 is communicated with a portion facing the meshing portion of the pinion gears, sufficient oil is provided at the portion of the pinion gear facing the meshing portion of the pinion gears. Can be supplied.

The invention according to claim 5 is the differential device according to any one of claims 1 to 4, wherein the second passage slides directly on the differential case or via a thrust washer. The boss portion of the side gear is formed on the end surface.

In this differential device, since the second oil passage is formed on the end face of the side gear,
Supply of oil to the sliding portion between the differential case and the side gear is promoted, and lubricity is improved.

According to a sixth aspect of the present invention, there is provided the differential device according to any one of the second to fifth aspects, wherein
Are provided for each pair of pinion gears meshing with each other or for each pinion gear.

In this differential device, since the second oil passage is provided for each pair of pinion gears or for each pinion gear, lubrication performance is further improved.

According to a seventh aspect of the present invention, there is provided the differential device according to any one of the first to seventh aspects, wherein
The oil passage is characterized by being an oil groove provided in the differential case or the side gear, the other end of which is larger in distance from the rotation axis of the differential case than one end.

In this differential device, since the oil groove is provided in the differential case or the side gear, a sufficient amount of oil is introduced, and the oil is rotated from the minus end of the oil groove provided in the differential case or the side gear as compared with the one end. At the other end provided to increase the distance from the axis, the centrifugal force flows by the rotation of the differential case, and flows.
The lubricant is reliably supplied to the sliding portion and the meshing portion of the gear, and the lubricity of those portions is improved.

According to an eighth aspect of the present invention, in the differential device according to any one of the first to sixth aspects, an opening communicating with the storage hole is provided in the differential case, and the first oil is provided from outside the differential case. An oil circulation path is formed through the passage and extending from the second oil passage to the outside of the differential case through the opening.

In this differential device, an oil circulation path that passes through the first oil passage and extends from the second oil passage to the outside of the differential case through the opening is formed, so that the oil flow is smooth and lubrication is achieved. The effect is improved.

According to a ninth aspect of the present invention, in the differential device according to the seventh aspect, the first oil passage includes:
A helical oil groove having an inclination angle in a direction in which oil is introduced from the oil reservoir into the inside of the differential case by rotation of the differential case formed on the inner periphery of the boss portion of the differential case, and the second oil passage is formed in the differential case. The other end is an oil groove communicating with the spiral oil groove and the other end is an oil groove having a greater distance from the rotation axis of the differential case than the one end. An opening is provided at a large distance from the rotation side to communicate the inside and outside of the differential case, and oil introduced from the oil reservoir through the first oil passage is passed through the first oil passage from the second oil reservoir. Oil introduced,
An oil circulation passage for discharging the oil from the second oil passage to the outside of the differential case through the opening is formed.

In this differential device, when the differential case is rotated, the oil is actively formed by the first spiral oil groove formed on the inner periphery of the boss portion of the differential case and having an inclined angle in a direction to introduce the oil from the oil reservoir into the differential case. From the one end of the second oil groove formed in the differential case and communicating with the spiral first oil groove, flows by receiving the centrifugal force due to the rotation of the differential case, and slides between the differential case and the side gear from the other end. It is sufficiently and reliably introduced into the moving part, the meshing part of each gear, and the sliding part between the pinion gear and the housing hole. Thereafter, the oil receives centrifugal force due to the rotation of the differential case, and is discharged to the outside of the differential case from an opening that has a greater distance from the other end of the oil groove to the rotation axis of the differential case and communicates with the inside and outside of the differential case. In addition, the spiral oil groove allows oil that is scraped up by the differential case when the differential case rotates to be positively introduced into the differential case. By providing this lubrication path, the fluidizing action of the oil is sufficiently performed, and the lubricity and cooling performance of each part are improved.

[0030]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to FIGS.

FIG. 1 is a longitudinal sectional view of this embodiment. The left and right directions are the left and right directions in FIG. 1, and members and the like without reference numerals are not shown.

As shown in FIG. 1, the differential device 7
Of the casing body 31 and the cover 33
And are fixed with bolts. Differential case 31
Are disposed left and right side gears 35 and 37 both constituted by helical gears. The differential device 7 is supported by bosses 49 and 51 of the differential case 21 via a differential carrier (not shown) via bearings, and is immersed in the oil sump 8 when not driven to rotate.

Hollow boss 3 of each side gear 35, 37
9 and 41 are rotatably supported by bearings 43 and 45 of the differential case 21. On the inner side of the side gears 35 and 37, a thrust block 47 straddling the inner circumference thereof.
Are arranged, and the free ends of the side gears 35 and 37 are supported and centered.

The left and right output shafts pass through the bosses 49 and 51 of the differential case 21 and are spline-connected to side gears 35 and 37, respectively. Thrust washers 53 and 55 are disposed between the side gears 35 and 37 and the differential case 21, respectively, and a thrust washer 5 is provided between the side gears 35 and 37 (on the outer peripheral side of the thrust block 47).
7 are arranged.

The differential case 21 has long and short storage holes 59 and 6.
4 are formed at equal intervals in the circumferential direction. Long and short pinion gears 63 and 65 each formed of a helical gear are slidably and rotatably stored in these storage holes 59 and 61, respectively.

The long pinion gear 63 includes first and second gear portions 67 and 69 and a small-diameter shaft portion 71 connecting the first and second gear portions 67 and 69, and the first gear portion 67 meshes with the right side gear 37. Also, the first gear portion 7 of the short pinion gear 65
3 meshes with the left side gear 35, and the second gear portion 75 meshes with the second gear portion 69 of the long pinion gear 63.

The driving force of the engine for rotating the differential case 21 is transmitted from the pinion gears 63 and 65 to the side gears 35 and 3.
7, when a driving resistance difference occurs between the output shafts due to one-wheel idling on a bad road, etc., the driving force of the engine differs between the left and right sides due to the rotation of the pinion gears 63 and 65. Dynamic distribution.

During transmission of the torque, each of the pinion gears 63, 6
The tooth tip of No. 5 is pressed against the wall surfaces of the storage holes 59 and 61 by the reaction force of the engagement with the side gears 35 and 37, and frictional resistance is generated. Further, frictional resistance is generated between the end surfaces of the pinion gears 63 and 65 and the differential case 31 due to the meshing thrust force of the helical gear, and the thrust washer 5
Side gears 35, 37 and differential case 2 via 3, 55
1 or between the side gears 35, 37 via the thrust washer 57. These frictional resistances provide a torque-sensitive differential limiting function.

As shown in FIG. 1, the boss 4 of the differential case 21
Helical oil grooves 77, 79 having an inclination angle θ in a direction in which oil is introduced from the oil reservoir 8 into the differential case 21 by the rotation of the differential case 21 are provided on the inner circumferences of the first and second differential cases 21, 51.
Oil passage) is formed. The cover 33 has one end 80 communicating with the oil groove 77 and the other end 87 having a short pinion gear 65 and a left side gear 35 as shown in FIG.
A short pinion gear 65 radially outside the meshing portion
An oil groove 81 (second oil passage) is formed to extend in the direction of the meshing portion (the meshing portion) of the second gear portion 75 with the second gear portion 69 of the long pinion gear 63.

The casing body 31 has one end 84.
1 and 3, the other end 89 is extended radially outward from the meshing portion between the first gear portion 67 of the long pinion gear 63 and the right side gear 37, as shown in FIGS. Oil groove 85 having extended extension 83
(A second oil passage) is formed. Each oil groove 8
The other ends 87 and 89 of the first and the 85 are respectively one ends 80 and 84
The distance of the differential case 21 from the rotation shaft 26 is larger than that of the first case. These oil grooves 81 and 85 are formed when the casing body 31 and the cover 33 are cast.

The thrust block 47 is formed with two axial cutouts 91 at equal intervals in the circumferential direction, and an oil reservoir is formed between these cutouts 91 and the side gears 35 and 37. Also, the output shaft and the side gear 35,
A toothless portion is provided in a subline portion of the 37 with the boss portions 39 and 41 to form an oil flow path that communicates the oil grooves 77 and 79 of the differential case 21 with the oil reservoir.

The openings 93, 95, and 97 are formed.

Thus, the oil flows from the outside of the differential case 21 through the oil grooves 77, 79 (first oil passage), and from the oil grooves 81, 85 (second oil passage) to the openings 93, 95,
The oil circulates from the oil grooves 77 and 79 to the outside of the differential case 21 through the oil grooves 77 and 79, the missing tooth portion and the oil sump of the thrust block 47 through the oil circulation passage extending from the oil grooves 77 and 79 to the outside of the differential case 21. Is formed.

Accordingly, the oil that has flowed in or has been repelled from the oil reservoir in the differential carrier by the rotation of the differential case 21 flows from the oil grooves 77 and 79 into the differential case 21.
The oil grooves 81, 8
After flowing through the gear 5, the oil is supplied to the sliding parts of the side gears 35 and 37, the thrust washers 53 and 55, and the differential case 21, and the oil lubricating these sliding parts is meshed with the gears and the storage holes 59 and 61. After being lubricated, the wall is discharged from the differential case 21 through the openings 93, 95, and 97 by centrifugal force and returned to the oil reservoir of the differential carrier.

As described above, by forming the oil circulation path, the flow of the oil becomes smooth, and the lubrication effect and the cooling effect in the differential case are improved. In particular, the oil circulation path extends from the oil grooves 77, 79 to the openings 93, 95, 97.
, The distance from the rotating shaft of the differential case is always set to be large, so that the oil is pushed radially outward due to centrifugal force, and the flow of oil is promoted.

Further, when a differential rotation occurs between the two side gears 35 and 37, the oil in the oil groove 81 is discharged from the second gear portion 75 of the short pinion gear 65 to the short pinion gear 65.
Is meshed with the second gear portion 75 of the long pinion gear 63 and the second gear portion 69 of the long pinion gear 63, the oil is introduced into this meshing portion, the flow of oil is promoted, and the first gear portion 73 of the short pinion gear 65 and the left side gear The oil introduced into the meshing portion with the portion 35 is pushed into the sliding portion between the side gear 35, the thrust washer 53, and the differential case 21 by the pumping action of the gear.

On the oil groove 85 side, the oil is sucked from the extension 83 by the pumping action due to the engagement of the first gear 67 of the pinion gear 63 and the right side gear 37, and the flow of the oil is promoted. By this pump action, the oil is pushed into the sliding portion between the side gear 37, the thrust washer 55, and the differential case 21.

Thus, the sliding portions between the side gears 35 and 37, the thrust washers 53 and 55 and the differential case 21, the meshing portions of the respective gears, and the long and short pinion gears 63 and 65 are provided.
A large amount of oil is reliably supplied to other lubricating portions such as the storage holes 59 and 61, and the lubricity is further improved. Then, by this, the side gears 35 and 37 and the thrust washer 5
In addition to preventing seizure and galling of the sliding portion between the third and 55 and the differential case 21 and the sliding portion between the pinion gears 63 and 65 and the storage holes 59 and 61, the pinion gears 63 and 65 are prevented.
Pitching and galling at the meshing portions between the gears and the side gears 35 and 37 and the meshing portion between the pinion gears 63 and 65 are prevented.

On the other hand, the oil introduced into the inside of the differential case 21 from the oil grooves 77 and 79 enters the oil sump of the thrust block 47 through the toothless portion of the spline portion.
While lubricating the sliding portion between the thrust block 47 and the side gears 35 and 37, the centrifugal force pushes the sliding portion to the thrust washer 57 side to lubricate the sliding portion with the side gears 35 and 37. After lubricating the wall surfaces of the storage holes 59 and 61, the oil is discharged from the openings 93, 95 and 97 to the outside of the differential case 21 by centrifugal force and returns to the oil reservoir of the differential carrier.

As described above, by forming the oil circulation path, the oil flow becomes smooth, and the lubrication effect is improved.

In this embodiment, since each gear is constituted by a helical gear, the gear thrust force corresponding to the input torque to the differential case 21 is particularly large in the side gear 3.
5, 37, thrust washers 53, 55 and differential case 3
Although the pressure applied to the sliding portion increases during the sliding portion, the formation of the oil groove of the present invention allows sufficient oil to be introduced into the sliding portion.

Further, since the outer diameter of the thrust block 47 is larger than the inner diameter of the boss portions 39 and 41, the flow of oil is promoted by centrifugal force, and the thrust washer 57 and the side gears 35 and 37 slide. The lubricity of the moving part and other lubricating parts is further improved.

The sliding portions between the thrust washers 53 and 55, the side gears 35 and 37 and the differential case 21, the sliding portions between the thrust washers 57 and the side gears 35 and 37, the pinion gears 63 and 65 and the storage holes 59 of the differential case 21, 6
Since a large amount of oil is supplied to the sliding portion 1 and the meshing portion of each gear, and the lubrication is sufficiently and reliably lubricated, the conventional case in which seizure or galling has occurred has been reduced to a differential case. In an experiment in which the input drive torque was doubled the conventional value and the other conditions were the same as the conventional one, it was confirmed that there was no occurrence of image sticking or galling. Therefore, by adopting this structure, a stable differential limiting function can be obtained.

When this differential device 7 is mounted on a vehicle, the above-mentioned seizure or galling at the sliding portion and each gear meshing portion does not occur, so that a stable differential limiting function can be obtained and excellent maneuverability can be obtained. Stability is obtained.

Since the space between the side gears 35 and 37 and the differential case 21 is sufficiently lubricated as described above, the side gears 35 and 37 and the differential case 21 are directly slid not through the thrust washers 53 and 55. May be moved.

The oil groove is not limited to the above embodiment,
For example, an oil groove may be provided on the outer periphery of the output shaft as the first oil passage, and an oil groove may be formed on the end face of the side gear boss as the second oil passage. Also, the oil groove 81,
The number of 85 may be further increased, may be provided for each pair (or set) of pinion gears, or oil grooves 81 and 85 may be provided corresponding to all the pinion gears.
If a large number of oil grooves are provided, the lubrication performance naturally improves accordingly. Further, the oil grooves 81 and 85 may be directly conducted to the meshing portions of the pinion gears 63 and 65 with each other. In this case, the lubrication of the meshing portions is further improved (the invention of claim 3).

FIGS. 4 and 5 show the configuration of a cover 33B in a differential device according to another embodiment when oil grooves (second oil passages) are provided by the number of pairs (sets or sets) of pinion gears. It is.

FIG. 4 shows the cover 3 viewed from the inside of the differential case.
FIG. 5 is an inner view of 3B, and FIG. 5 is a cross-sectional view taken along line CC of FIG.
In the figure, the same components as those of the embodiment of FIG.

In the cover 33B, two spiral oil grooves 77 are provided on the inner periphery of the boss 49. Also, the second
Are provided at equal intervals in the circumferential direction. Then, each spiral oil groove 71
And one end 80, 80 of two adjacent oil grooves (second oil passages) 81, 81, respectively, and all the oil grooves 81 communicate with a spiral oil groove 77 as a first oil passage. Let me.

In this example, the oil groove 81 is positioned at a position corresponding to the pinion gear on the trailing side in the normal rotation direction of the differential case (rotation direction during forward movement) (in FIG. 4, the rotation direction is R). , Of the pair of storage holes 61, 63 is provided in the storage hole 63 on the rear side in the rotation direction. This is because, when the pinion gear on the trailing side revolves together with the differential case, the frictional force against the storage hole becomes larger than that of the preceding pinion gear. By introducing the oil to the pinion gear side directly following in this way, lubrication to the friction portion is sufficiently performed.

When the oil groove 81 is guided to a position corresponding to the preceding pinion gear, the effect that the oil smoothly spreads from the preceding pinion gear to the following pinion gear by rotation of the differential case can be expected.

Although not shown, the oil grooves 85 and 79 (see FIG. 1) on the differential case side have substantially the same structure, the number of oil grooves 85 is four, and the spiral oil groove 79 is two. .

Next, still another embodiment will be described.

FIG. 6 is a side sectional view of the same embodiment, and FIG. 7 is an inner view of the cover as viewed from the inside of the differential case. FIG.
7 corresponds to a cross-sectional view taken along the line DD in FIG.

The differential device 2 of this embodiment
The 00 differential case 221 includes a casing body 231 having a side wall 232 and a cylindrical boss 234, and a cover 233 having a cylindrical boss 235. Cover 2
Reference numeral 33 is connected to the casing main body 231 with a bolt (not shown) so as to close the opening surface opposite to the side wall portion 232. Left and right output side gears 239 and 241 are disposed inside the differential case 221.

The left side gear 239 in FIG.
, And the right side gear 241 is spline-connected to a right output shaft (not shown) via a boss 245. Each output shaft (rotary shaft) is provided through the boss 235 of the cover 233 and the boss 234 of the casing body 231. A spiral oil groove (first oil passage) 7 is formed in each inner periphery of the boss 235 of the cover 233 and the boss 234 of the casing body 231 as in the embodiment shown in FIG.
7, 79 are formed.

The bosses 243 and 245 of the side gears 239 and 241 and the differential case 221 or the cover 233
Are disposed between the side gears 239 and 241, and a washer 255 is disposed between both side gears 239 and 241.

The differential case 221 has a pair of storage holes 2.
57, 259 are plural sets (multiple sets) at equal intervals in the circumferential direction
Is formed. Pinion gears 261 and 263 are slidably and rotatably housed in the housing holes 257 and 259, respectively. In this case, the pinion gears 261 and 263 have the same shape, and are simply inserted into the storage holes 257 and 259 in the opposite direction. Note that the side gears 239, 241,
The gear portions of the pinion gears 261 and 263 are constituted by helical gears.

The pinion gears 261 and 263 are composed of first gear portions 265 and 266, second gear portions 267 and 268, and small diameter shaft portions 269 and 270 connecting these. The first gear portion 265 of one pinion gear 261 meshes with the left side gear 239. Also, the first gear portion 266 of the other pinion gear 263 housed in the opposite direction
Are engaged with the right side gear 241. And
Second gear portion 26 of both pinion gears 261, 263
7, 268 mesh with each other. The intermeshing portions are both ends in the axial direction of the pinion gears 261 and 263, and the pinion gears 261 and 263 are located between the intermeshing portions.
An engagement portion between the gear 263 and the side gears 239 and 241 is located.

A center hole 275 serving as a chuck hole at the time of lathe machining is provided at both end surfaces of the pinion gears 261 and 263.
Is provided. In addition, these pinion gears 261,
Storage holes 257 and 2 of the differential case 221 for storing the H.263.
The oil grooves extending in the radial direction of the differential case 221 are provided on the inner surface of the side wall portion 232 of the casing main body 231 and the inner surface of the cover 233 (the sliding surfaces of the pinion gears 261 and 263 and the side gears 239 and 241) in correspondence with the position 59. 277 and 278 are formed. These oil grooves 277 and 278 serve as second oil passages, and inner end portions (one ends) 277a and 278a are provided in the first oil passage.
, And extend continuously to a position where the outer peripheral end portions (the other ends) 277b and 278b communicate with the center hole 275 provided in the end surfaces of the pinion gears 261 and 263. ing. In order to reliably connect the spiral oil grooves 77 and 79 to the oil grooves 277 and 278 as the second oil passage, the boss portion 23 is used.
5 and 234 are provided with chamfers 236 and 237 at the opening edges of the through holes into the differential case 221, and the spiral formed by the gaps formed between the chamfers 236 and 237 and the washers 251 and 253. Oil grooves 77 and 79, and a second
And all oil grooves 277 and 278 as oil passages communicate with each other. Even if an annular notch or a step is provided instead of the chamfers 236 and 237, all the oil grooves 27
7, 278 can be communicated with the spiral oil grooves 77, 79.

The differential case 221 has a plurality of openings 279 communicating with the storage holes 257 of the pinion gear 261.
And a plurality of openings 281 communicating with the storage holes 259 of the pinion gear 263. When the differential device 200 rotates, the oil splashed from an oil sump of a differential carrier (not shown) by a ring gear (not shown), The openings 279 and 281 flow into and out of the differential case 221.

The differential device 2 of this embodiment
00, an oil groove 277 as a second oil passage,
278 was continuously extended to a position communicating with the center hole 275 on the end face of the pinion gears 261 and 263.
Oil taken from spiral oil grooves 77, 79,
Sliding portions between the end faces of the side gears 239 and 241 and the differential case 221, meshing portions between the side gears 239 and 241 and the pinion gears 261 and 263, and the pinion gears 261 and 263
The sliding portion between the end surface of the housing 63 and the differential case 221 can be sufficiently spread.

Therefore, the lubrication of those portions can be sufficiently performed, and the occurrence of seizure, galling, and abnormal noise can be prevented. In particular, the pinion gears 261, 2
The lubrication of the sliding portion between the end face of the end portion 63 and the end faces of the side gears 239 and 241 is improved, so that the differential limiting characteristic is stabilized. In addition, the oil is supplied to other sliding parts and the pinion gear 2.
61 and 263, so that they are sufficiently distributed
The overall lubricity can be improved. As for the circulation of oil, openings 279 and 281 are formed in the outer peripheral wall of the differential case 221.
Therefore, the same effect as in the embodiment shown in FIG. 1 can be expected.

As shown in the oil groove 278 on the right side in FIG. 6, a step 2 is formed halfway from one end 278a to the other end 278b.
If the cross-sectional area of the oil groove 278 is reduced between the one end 278a and the other end 278b, the speed at which oil flows through the oil groove 278 can be increased by centrifugal force when the differential case 221 rotates. Pinion gear 26
The effect of pushing the oil into the end faces of the first and second 263 can be more effectively performed.

Further, regarding the location where the oil groove is provided,
Not limited to the above embodiment, for example, an oil groove may be provided on the outer periphery of the output shaft as a first oil passage, and an oil groove may be formed on an end face of a boss portion of the side gear as a second oil passage.

As described above, the differential devices 7 and 200
However, the differential device according to the present invention is also used in a rear differential, a front differential (axle differential on the front wheel side) and a center differential (a differential device for distributing driving force to front and rear wheels).

[0077]

As described above, according to the first aspect of the present invention, the rotation of the differential case causes the oil to flow into the first oil passage formed between the inner periphery of the boss portion of the differential case and the outer periphery of the output shaft. The supplied oil is supplied from one end of the second oil passage communicating with the first oil passage to a sliding portion between the side gear at the other end and the differential case, so that lubricity of this portion is improved and seizure is prevented. And a stable differential limiting function can be obtained.

Further, since the other end of the second oil passage communicates with a portion opposed to the meshing portion between the pinion gear and the side gear, the inflowing oil is supplied to the sliding portion between the side gear and the differential case, and then the pinion gear is connected to the pinion gear. It is supplied to a portion facing the meshing portion with the side gear. Therefore, the sliding portion between the side gear and the differential case, the meshing portion between the pinion gear and the side gear, the seizure between the pinion gear and the housing hole, and galling are sufficiently prevented. Further, when the meshing rotation of the pinion gear and the side gear occurs, the supply of oil to the sliding portion between the side gear and the differential case is further promoted by the pumping action between these gears, so that seizure and galling of this portion are further prevented. You.

According to the second aspect of the present invention, the other end of the second oil passage communicates with the portion of the pinion gear facing the meshing portion, so that the inflowing oil is supplied to the sliding portion between the side gear and the differential case. After that, the pinion gear is supplied to a portion facing the meshing portion of the pinion gear. Therefore, the sliding portion between the side gear and the differential case and the meshing portion of the pinion gear and the seizure between the pinion gear and the storage hole and galling are sufficiently prevented.

According to the third aspect of the invention, the other end of the second oil passage communicates with the end face of the side gear and the sliding portion of the differential case, and also communicates with the end face of the pinion gear and the sliding portion of the differential case. Thus, the end surfaces of the side gears and the pinion gears can be sufficiently lubricated. Therefore, when the gear portion is formed of a helical gear, the sliding friction due to the meshing thrust is large, and the sliding portion that greatly affects the differential limiting characteristic can be sufficiently lubricated, thereby stabilizing the differential limiting characteristic. Can be achieved.

According to the fourth aspect of the present invention, since the second oil passage is further communicated with the meshing portion of the pinion gear, seizure and galling between the pinion gear and the housing hole are sufficiently prevented.

According to the fifth aspect of the present invention, since the second oil passage is formed at the end face of the boss portion of the side gear,
Supply of oil to the sliding portion between the differential case and the side gear is promoted, and lubricity is improved.

According to the sixth aspect of the present invention, the lubricating performance of the sliding portions of all the pinion gears is increased, generating abnormal noise and seizure.
Galling or the like can be more reliably prevented.

According to the seventh aspect of the present invention, since the oil groove is provided in the differential case or the side gear, a sufficient amount of oil is introduced, and the oil flows from the negative end of the oil groove provided in the differential case or the side gear to the one end. At the other end provided to increase the distance from the rotation shaft of the differential case, the differential case flows by receiving the centrifugal force due to the rotation of the differential case, and is reliably supplied to the sliding portion and the gear meshing portion. Therefore, burn-in and galling of those portions can be prevented.

According to the eighth aspect of the present invention, an oil circulation path that passes through the first oil passage and extends from the second oil passage to the outside of the differential case through the opening is formed.
The oil flow is smooth and the lubrication effect is improved.

According to the ninth aspect of the present invention, when the differential case rotates, the oil is formed on the inner periphery of the boss portion of the differential case by the spiral oil groove having an inclination angle in a direction in which the oil is introduced from the oil reservoir into the differential case. Actively introduced, the centrifugal force is caused by the rotation of the differential case from one end of the oil groove formed in the differential case and communicated with the spiral oil groove, and flows from the other end, and the sliding portion between the differential case and the side gear and the engagement of each gear. It is sufficiently and reliably introduced into the sliding portion between the housing portion and the pinion gear. Thereafter, the oil receives centrifugal force due to the rotation of the differential case, and is discharged from the other end of the oil groove to the outside of the differential case through an opening that has a large distance from the rotation axis of the differential case and communicates with the inside and outside of the differential case. In addition, the spiral oil groove can also actively introduce oil that is scraped up by the differential case during rotation of the differential case into the differential case. By providing the lubricating passage, the fluidizing action of the oil is sufficiently performed, and the lubricating property and the cooling property of each part are improved, so that seizure and galling are prevented.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a sectional view taken along line BB of FIG. 1;

FIG. 4 is an inner view of a cover of a differential case according to another embodiment of the present invention.

FIG. 5 is a sectional view taken along line CC of FIG. 5;

FIG. 6 is a side sectional view of a differential device according to still another embodiment of the present invention.

FIG. 7 is an inner view of a cover forming a differential case of the differential device.

FIG. 8 is an exploded perspective view of a conventional example.

FIG. 9 is a sectional view of another conventional example.

FIG. 10 is a sectional view of still another conventional example.

FIG. 11 is an external view of the conventional example.

[Explanation of symbols]

7,200 Differential device. 8 Oil reservoir 21,221 Differential case 26 Rotating shaft 35,37,239,241 Side gear 49,51,234,235 Boss 53,55,253,255 Thrust washer 59,61,257,259 Storage holes 63,65,261 263 Pinion gear 77, 79 Oil groove (first oil passage) 81, 85, 277, 278 Oil groove (second oil passage) 80, 84, 277a, 278a-End 87, 89, 277b, 278b Other end 93 , 95,97,279,281 opening

Continuation of the front page (72) Inventor Wako Kogagami 2388 Omiyacho, Tochigi City, Tochigi Prefecture Tochigi Fuji Sangyo Co., Ltd. (56) References JP-A-6-207645 (JP, A) JP-A-6-207646 (JP, A) Japanese Utility Model Application Laid-open No. 3-44261 (JP, U) Japanese Utility Model Application Laid-Open No. 6-16750 (JP, U) International Publication No. 94/9291 (WO, A1) International Publication No. 94/7054 (WO, A1) US Pat. A) (58) Field surveyed (Int. Cl. ⁷ , DB name) F16H 57/00-57/04 F16H 48/20

Claims (9)

(57) [Claims] 1. A differential case arranged in an oil sump and rotationally driven by an engine, a pair of output side gears each of which slides through the thrust washer or directly with the differential case, and a radially outer side gear of the side gear. At least one pair of pinion gears arranged and meshing with each other and separately meshing with the side gears; a storage hole formed in the differential case for slidably and rotatably storing the pinion gears; a boss portion of a differential case through which an output shaft connected to the side gears passes; A first oil passage formed between the outer periphery of the shaft and the inner periphery of the boss portion; and a first oil passage formed between the differential case and the side gear and having one end communicating with the first oil passage and the other end including the side gear and the differential case.
And the pinion gear and side gear
The second oil communicated with the portion facing the meshing portion
A differential device comprising a passage . 2. An engine disposed in an oil sump.
The differential case, which is driven to rotate, and the respective end faces are connected via thrust washers or directly
A pair of output side gears that slide with the contact differential case, and are disposed radially outside the side gears and mesh with each other.
At least one pair of pinions that mesh with the side gears
Gear and the pinion gear formed in the differential case are slidably and rotatably housed.
The output hole connected to the side gear and the output shaft
A first case formed between the outer periphery of the output shaft and the inner periphery of the boss portion, and a boss portion of the differential case that passes therethrough.
One end formed between the oil passage, the differential case and the side gear has the one end.
The other end communicates with the oil passage and the other side gear and differential case
And the pinion gears engage with each other.
A second oil passage communicating with a portion facing the mating portion is provided.
Differential and wherein the was e. 3. An engine disposed in an oil sump.
The differential case, which is driven to rotate, and the respective end faces are connected via thrust washers or directly
A pair of output side gears that slide with the contact differential case, and are disposed radially outside the side gears and mesh with each other.
At least one pair of pinions that mesh with the side gears
Gear and the pinion gear formed in the differential case are slidably and rotatably housed.
The output hole connected to the side gear and the output shaft
A first case formed between the outer periphery of the output shaft and the inner periphery of the boss portion, and a boss portion of the differential case that passes therethrough.
One end formed between the oil passage, the differential case and the side gear has the one end.
The other end communicates with the oil passage of No. 1 and the end face of the side gear
While communicating with the sliding part with the case, the end of the pinion gear
Second oil passage communicating with a sliding portion between the surface and the differential case
Differential apparatus, comprising the. 4. The differential device according to claim 3,
A is, the other end of the second oil passage, the pinion gear mutual meshing
A differential device, wherein the differential device communicates with a portion facing the engagement portion . 5. The method according to claim 1, wherein
A differential device, wherein the second oil passage directly or indirectly connects the differential case.
Of the side gear boss through the thrust washer
A differential device formed on an end face . 6. A diff according to any one of claims 1 to 5,
A differential gear, wherein said second passage is formed by a pair of intermeshing pinion gears.
Provided for each pinion gear or each pinion gear
A differential device, characterized in that: 7. The diff according to any one of claims 1 to 6,
A differential device, wherein the second oil passage is provided with a differential case or a side gear.
The other end is provided on the rotating shaft of the differential case as compared with the one end.
A differential device characterized by an oil groove that increases the distance between them. 8. The method according to claim 1, wherein
A differential device, wherein the differential case is
An opening that communicates with the storage hole is provided, and from the outside of the differential case
The first oil passage passes through the second oil passage, and
The oil circulation path through the mouth to the outside of the differential case is shaped
A differential device characterized by being formed . 9. The differential according to claim 7, wherein
Therefore, the first oil passage is formed on the inner periphery of the boss of the differential case.
The oil is collected from the oil sump by rotating the differential case.
An angle of inclination was given in the direction to introduce oil into the case.
A helical oil groove, wherein the second oil passage is formed in a differential case and has one end
The other end communicates with the spiral oil groove and the other end is
An oil groove for increasing the distance from the rotation axis of the base to the differential case.
The distance from the rotating shaft is large and communicates inside and outside the differential case
And an opening that is introduced from the oil reservoir through the first oil passage.
Oil from the second oil passage through the opening.
A differential device, wherein an oil circulation path for discharging the oil to the outside of the case is formed .