JPH08334165A - Differential device - Google Patents

Abstract

(57) [Summary] [Purpose] To improve the oil intake efficiency of the oil pump and the response of the differential limiting function. [Structure] A differential case 5 housed in the housing 3,
The differential mechanism 53 and the friction clutch 57 that limits the differential.
An oil pump 61 driven by differential rotation to suck oil from the opening 85 of the case 5, a hydraulic actuator 59 receiving hydraulic pressure of the pump 61 and engaging the clutch 57, and a case 5 fixed to the housing 3 side. In contrast, an oil pocket 97 that is liquid-tight and slidably arranged, an oil scraping portion 119 that is provided in the case 5 and scrapes oil from the oil sump of the housing 3, and a scraped oil that is provided in the housing 3 An oil guide portion 121 is provided which guides the oil pocket 97 against the reflection surface 131.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a differential device used in a vehicle.

[0002]

2. Description of the Related Art U.S.P. S. Patent 5310388
The certificate registration certificate describes a differential device 201 as shown in FIG.

This differential device 201 includes a pinion shaft 205 fixed to a differential case 203,
A bevel gear type differential mechanism 213 including a pinion gear 207 rotatably supported on a pinion shaft 205, and side gears 209 and 211 meshing with the pinion gear 207, a multi-disc clutch 215 for limiting a differential, and a multi-disc clutch 215. Actuator 217 for fastening
And an oil pump 219 for operating the hydraulic actuator 217. The side gears 209 and 211 are splined to the axles 221 and 223, respectively.

Multi-plate clutch 215 and oil pump 219
Is the axle 221 of the side gear 207 and the differential case 20.
3, the oil pump 219 is driven by receiving the differential torque of the differential mechanism 213 via the axle 221 and sends the hydraulic pressure to the hydraulic actuator 217 to engage the multi-plate clutch 215.

An oil sump is formed in the differential carrier for accommodating the differential device 201, and the oil pump 219 sucks oil from the oil sump through the suction port 225 of the differential case 203 and the check valve 227.

[0006]

As described above, in the differential device 201, since the oil pump 219 is configured to directly suck the oil from the oil reservoir of the differential carrier, the oil level 229 of the oil reservoir is set to the suction port 225. Must be above position. However, when the differential device 201 rotates, the oil may be attracted to both sides in the axial direction due to the centrifugal force, the oil level 229 near the suction port 225 may be lowered, and the oil may not be sucked. Therefore, the amount of oil in the oil sump must be increased in consideration of this.

However, when the oil amount is increased, the rotational resistance of the oil received by the differential device 201 is increased by that much, and the fuel efficiency of the engine is deteriorated. Also, oil level 2
If the vehicle is tilted and the suction port 225 goes above the oil level 229 even if 29 is raised, the oil pump 219
Cannot suck the oil and loses the differential limiting function.

Therefore, as shown in FIG. 5, the differential case 2
There is a structure in which an oil pocket 231 for covering the suction port 225 is provided on the side surface of 03, an oil tube 233 is further connected to this oil pocket 231, and the oil is sucked by relaying the oil tube 233 from the oil reservoir. .

However, in such a structure, oil is stored in the oil reservoir, the oil tube 233, and the oil pocket 23.
1 and the suction port 225 and the like, the oil flow path is long, and in particular, the flow path resistance in the oil tube 233 is large. Therefore, the oil suction efficiency of the oil pump 219 becomes low, the hydraulic pressure supply to the hydraulic actuator 217 is obstructed, and the response of the differential limiting function deteriorates. In addition, the oil tube 233 is required, and the number of parts is large.

Further, when the vehicle leans or receives a lateral G while turning, the oil in the oil reservoir may deviate and air may enter from the all tube 233. In this case, the differential limiting force is large. descend.

Therefore, the present invention is a differential device in which a hydraulic actuator for engaging a friction clutch for limiting a differential is operated by a built-in oil pump. It is an object of the present invention to provide a differential device with improved response of the limiting function.

[0012]

According to another aspect of the present invention, there is provided a differential device including a housing having an oil sump, a differential case arranged inside the housing and rotationally driven by a driving force of an engine, and a differential arranged in the differential case. A mechanism, a friction clutch that limits the differential of the differential mechanism, an oil pump that is driven by the differential rotation of the differential mechanism and that sucks oil from an oil suction port that opens in the differential case,
It is fixed to the housing side in a fluid-tight and slidable contact with the hydraulic actuator that presses and engages the friction clutch by receiving the oil pressure of the oil pump, and the oil level is above the oil intake port. An oil pocket that forms an oil reservoir to be maintained inside, an oil scraping part that is provided on the side surface of the differential case and scrapes oil from the oil pool of the housing, and the scraped oil that is provided on the housing side is applied to the reflective surface. And an oil guide portion for guiding the oil to the oil reservoir of the oil pocket.

A differential device according to a second aspect of the present invention is the differential device according to the first aspect, wherein the oil scraping portion has an oil holding portion and an opening portion for scraping the oil and discharging the oil toward the oil guide portion. is there.

A differential device according to a third aspect of the present invention is the differential device according to the first or second aspect, wherein the oil scraping portion is formed integrally with the differential case.

According to another aspect of the differential device of the present invention, the reflecting surface of the oil guide portion corresponds to the flying angle of the oil which changes depending on the rotation speed of the differential case, and guides the oil to the oil sump of the oil pocket in a wide rotation speed range of the differential case. 4. The differential device of claim 1, 2 or 3 having different slopes.

In the differential device according to claim 5, the oil guide portion is arranged above the oil pocket in the direction of gravity, and the splashed oil is dropped into the oil sump of the oil pocket. Is.

According to another aspect of the present invention, there is provided a differential device having oil scraping portions respectively corresponding to both rotation directions of the differential case, and the oil guide portion having reflecting surfaces respectively corresponding to the oil scraping portions for each direction. The differential device according to claim 1, 2, 3, 4, or 5.

[0018]

In the differential device according to each of the claims, when differential rotation occurs, the oil pump is driven, the hydraulic actuator receives the hydraulic pressure, and the friction clutch is pressed to limit the differential. Since the oil pressure of the oil pump becomes stronger as the differential rotation speed increases, this differential limiting function is speed sensitive.

Further, an oil sump is formed in the housing for accommodating the differential case, an oil pocket is slidably provided on the side surface of the differential case, and the oil is scooped up from the oil sump of the housing. Section is provided. In addition, the housing is provided with an oil guide portion that puts the scraped oil on the reflecting surface and puts it in the oil pocket.

Thus, as long as the differential case is rotating, the oil scraped from the oil sump of the housing is supplied to the oil pocket, and the oil level in the oil pocket is higher than the oil suction port for the oil pump provided in the differential case. keep.

As described above, since the oil pump is constructed so that oil can be directly sucked from the oil pocket, the oil passage is short and the passage resistance is small unlike the conventional example. Therefore, the oil suction efficiency is improved and the response of the differential limiting function is greatly improved. Further, the oil tube unlike the conventional example is unnecessary, and the number of parts is small.

The oil level of the housing is sufficient as long as the scraping part of the differential case is submerged,
It is not necessary to make it higher than the opening (oil intake) of the differential case. Therefore, the rotational resistance of the oil received by the differential device is correspondingly reduced, and the fuel efficiency of the engine is greatly improved.

Further, the oil pocket is arranged almost in close contact with the differential case, and the oil level thereof is substantially unaffected by the inclination of the vehicle, the lateral G, etc., so that the oil pump is not affected by the running condition or the road surface condition. Oil can always be sucked in stably, and a stable differential limiting function can be obtained.

A differential device according to a second aspect of the present invention is the differential device according to the first aspect, wherein the oil scraping portion is constituted by an opening portion for discharging the oil toward the oil holding portion and the oil guide portion. The differential device according to claim 3 is the differential device according to claim 1 or 2, wherein the oil scraping portion is formed integrally with the differential case.

Similar to the differential device according to the first or second aspect of the invention, the response of the differential limiting function is improved, the rotational resistance due to oil is small, the engine fuel consumption is improved, and it is stable regardless of the running condition or the road surface condition. A differential limiting function is obtained and the number of parts is small.

In addition to this, in the structure of the second aspect, by providing the oil holding portion, the oil scraping efficiency of the oil scraping portion is improved, and the oil supply amount to the oil pocket is increased. Further, in the configuration of claim 3, the oil scraping portion can be processed integrally with the differential case (for example, casting processing), so that the cost is low.

A differential device according to a fourth aspect of the present invention is the differential device according to the first, second or third aspect, in which the reflecting surface of the oil guide portion has different gradients corresponding to the flying angle of the oil which changes depending on the rotation speed of the differential case. The differential case is configured so that the oil can be guided to the oil sump of the oil pocket in a wide rotation speed range of the differential case, and the response of the differential limiting function is improved as in the differential device according to claim 1, 2 or 3. , The engine fuel consumption is improved, the stable differential limiting function is always obtained regardless of the driving conditions, and the number of parts is small.

In addition to this, even if the rotation speed (vehicle speed) of the differential case changes in a wide range, the oil is effectively supplied to the oil pocket, and the above-mentioned respective effects are stably obtained.

The differential device according to claim 5 is the differential device according to claim 1, 2, 3 or 4.
The oil guide portion is arranged above the oil pocket in the direction of gravity, and like the differential device according to claim 1, 2, 3, or 4, the response of the differential limiting function and the engine fuel consumption are improved, and the running condition etc. Regardless of this, a stable differential limiting function is always obtained, and the number of parts is small.

In addition to this, the oil guide portion arranged above the oil pocket in the direction of gravity supplies the oil that has flown in to the oil pocket not only by reflecting it but also by dropping it. In this way, the oil sump in the oil pocket is always kept at a sufficiently high oil level, so that the oil pump can stably suck the oil, and the above-described respective effects can be stably obtained.

A differential device according to a sixth aspect of the present invention is the differential device according to the first, second, third, fourth, or fifth aspect, in which the oil scooping portions corresponding to both directions of rotation of the differential case are formed and the oil guide portion is provided. The oil scooping portion for each of these directions is provided with a reflecting surface corresponding to each of them, and the response of the differential limiting function and the engine fuel consumption are the same as in the differential device according to claim 1, 2, 3, 4 or 5. And, the stable differential limiting function is always obtained regardless of the driving conditions, and the number of parts is small.

In addition to this, the oil scooping portion and the reflecting surface of the oil guide portion are formed so as to correspond to both rotation directions of the differential case (when the vehicle is traveling forward and when the vehicle is traveling backward). Oil is constantly supplied to the oil pocket regardless of the direction, and each of the above effects can be stably obtained.

[0033]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A differential device 1 which is an embodiment of the present invention will be described with reference to FIGS. This embodiment has the features of claims 1, 2, 4, 5, and 6. In addition,
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 1 is arranged inside a differential carrier 3 (housing). An oil reservoir is formed on the differential carrier 3.

The differential case 5 of the differential device 1 includes a casing body 9 having a right boss portion 7 and a cover 13 having a left boss portion 11, which are fixed by bolts. The bosses 7 and 11 are supported by bosses 17 and 17 formed on the left and right of the differential carrier 3 via bearings 15 and 15, respectively. A ring gear 21 is fastened to the casing body 9 and the cover 13 together with a bolt 19. The ring gear 21 meshes with the drive gear of the drive force transmission system, and the differential case 5 is rotationally driven by the drive force of the engine via the transmission and the drive force transmission system.

As shown in FIG. 1, inside the differential case 5,
A plurality of pinion shafts 25 centering around the boss portion 23
Are radially arranged, and the outer end of each pinion shaft 25 is supported by the groove 27 of the differential case 5. A pinion gear 29 is rotatably supported on each pinion shaft 25.

Left and right side gears 31, 33 (output side gears) are arranged inside the differential case 5. The side gears 31 and 33 are respectively bosses 35 and 3
7 is integrally formed. These side gears 31, 3
3 is supported from the outside in the radial direction by meshing with the pinion gear 29. Pinion gear 29 and differential case 5
A spherical washer 39 is provided between the pinion gear 29 and the pinion gear 29, and bears the meshing reaction force received by the pinion gear 29 due to the centrifugal force of the pinion gear 29 and the meshing with the side gears 31 and 33.

The boss portion 35 of the left side gear 31 is rotatably supported by the bearing portion 41 of the differential case 5 and the inner periphery of the boss portion 45 of the pump case 43 described later, and the boss portion 37 of the right side gear 33 is the bearing portion 47 of the differential case 5. It is rotatably supported by. A washer 49 is arranged between the left side gear 31 and the pump case 43, and a washer 51 is arranged between the right side gear 33 and the differential case 5. The side gears 31 and 33 are spline-connected to the output shaft via the boss portions 35 and 37, respectively.

In this way, the bevel gear type differential mechanism 53 is constructed. Pinion shaft 25 of the differential mechanism 53
The pinion gear 29 and the side gears 31 and 33 can be appropriately moved in the axial direction.

The driving force of the engine 1 for rotating the differential case 5 is distributed from the pinion shaft 25 to the side gears 31 and 33 via the pinion gear 29 and is transmitted to the wheel side via each output shaft. Further, for example, when a driving resistance difference occurs between the wheels during traveling on a rough road, the driving force of the engine is differentially distributed to the left and right sides by the rotation of each pinion gear 29.

A multi-plate clutch 57 (friction clutch) is arranged between the top 55 of the left side gear 31 and the differential case 5. A hydraulic actuator 59 is arranged on the left side of the hydraulic actuator 59, and an external gear pump 61 (oil pump) is arranged on the left side of the hydraulic actuator 59.

A back ring 63 is arranged between the multi-plate clutch 57 and the differential case 5 to bear the pressing force of the multi-plate clutch 57.

The piston 65 of the hydraulic actuator 59 is axially movable between the outer periphery of the boss portion 45 of the pump case 43 and the inner periphery of the differential case 5 via seals 67 and 69, respectively. The pressure chamber 71 of the hydraulic actuator 59 is formed between the piston 65, the pump case 43, and the differential case 5.

The gear pump 61 includes a pump case 43, a large diameter gear 73, four small diameter gears 75, and reed valves 77, 7.
It is composed of 9 and the like.

The pump case 43 has an outer periphery press-fitted into the differential case 5, and is further fixed to the differential case 5 with bolts. Storage holes 81 and 83 are provided in the pump case 43, and the storage holes 83 are formed outside the storage hole 81 at four locations at equal intervals in the circumferential direction. The storage holes 81 and 83 communicate with each other to form a pump chamber. The large-diameter gear 73 and the small-diameter gears 75 are slidably and rotatably housed in the housing holes 81 and 83, respectively, and mesh with each other in the pump chamber to form four pump functions. The inner circumference of the large diameter gear 73 is splined to the outer circumference of the boss portion 35 of the left side gear 31,
When differential rotation occurs in the differential mechanism 53, the small diameter gear 75 on the pump case 43 side fixed to the differential case 5 and the large diameter gear 73 on the left side gear 31 side rotate relative to each other, and these four pump functions operate. To do.

The cover 13 of the differential case 5 has an opening 85 corresponding to one side in the circumferential direction of the meshing portion of the large diameter gear 73 and each small diameter gear 75 and an opening (a total of eight openings) corresponding to the other side in the circumferential direction. The pump case 43 is provided with an opening 87 corresponding to one side in the circumferential direction of the meshing portion of the gears 73 and 75 and an opening corresponding to the other side in the circumferential direction (a total of eight openings).
Are provided.

The reed valves 77 and 79 are flexible members having a strip shape. The center portion of the reed valve 77 is fixed to the cover 13 by a pin 89, and the opening 8 is formed at a reed portion 91 on one side in the circumferential direction.
5, and the lead portion on the other side in the circumferential direction closes the opening on the other side. The center portion of the reed valve 79 is fixed to the pump case 43 with a pin 93, the lead portion 95 on one side in the circumferential direction closes the opening 87, and the lead portion on the other side in the circumferential direction closes the opening on the other side.

As shown in FIGS. 1, 2, and 4, the differential case 5
An oil pocket 97 is arranged on the side surface of the cover 13. As shown in FIG. 1, the oil pocket 97 is positioned on the boss portion 11 of the cover 13 by the retaining ring 99 and is appropriately pressed against the side surface of the cover 13, so that the contact portion with the cover 13 is in a liquid-tight state. Has been done. An oil reservoir is formed between the oil pocket 97 and the cover 13. As will be described later, the oil reservoir is sufficiently supplied with oil from the opening 101 of the oil pocket 97, and the oil level thereof is constantly maintained in the cover 13. It is kept on the upper side in the direction of gravity such as the opening 85.

As shown in FIGS. 2 and 3, the oil pocket 97 is fixed to the differential case holder 107 by the L-shaped metal fitting 103 and the bolt 105.
07 is fixed inside the differential carrier 3 by a bolt 109. At this time, the opening 10 of the oil pocket 97
1 is directed upward in the direction of gravity.

When a differential is generated in the differential mechanism 53, the large-diameter gear 73 and the small-diameter gears 75 mesh and rotate as described above, and the four pump functions of the gear pump 61 operate. The direction of rotation of each pump function is opposite depending on the direction of differential rotation.

For example, differential rotation occurs in the direction in which the opening 85 of the cover 13 and the opening 87 side of the pump case 43 become the suction side of each pump function, and when this differential rotation exceeds a certain number of rotations, these openings are opened. Reed valves 9 on one side of reed valves 77 and 79 that have blocked 85 and 87 (oil suction port)
1, 95 open, the gear pump 61 has an oil pocket 97
The oil is directly sucked from the oil sump and the hydraulic pressure is applied to the pressure chamber 71 of the hydraulic actuator 59. At this time, the openings (oil inlets) on the other side in the circumferential direction of the cover 13 and the pump case 43 are closed by the lead portions on the other side of the reed valves 77 and 79 to prevent hydraulic leakage of the hydraulic actuator 59.

When a differential rotation exceeding a certain number of rotations occurs in the opposite direction, the other circumferential side of each pump function changes to the suction side, and the reeds of the other sides of the reed valves 77 and 79 open. Oil is sucked from each of the openings on the other side to apply hydraulic pressure to the pressure chamber 71, and the lead portions 91 and 95 close the openings 85 and 87 to hold the hydraulic pressure of the hydraulic actuator 59.

When hydraulic pressure is applied to the pressure chamber 71, the hydraulic actuator 59 presses the multi-plate clutch 57 via the piston 65 to engage it. At this time, the rotation of the side gear 31 is braked by the pump work of each pump function and the frictional resistance of the multi-plate clutch 57, and the differential of the differential mechanism 53 is limited. Since the discharge pressure of the gear pump 61 increases as the differential rotation speed increases, this differential limiting function is a differential rotation speed sensitive type. Further, when the differential rotation speed becomes smaller than a certain value in any of the differential rotation directions, the reed valve 77,
It is blocked by 79, the pump function of the gear pump 61 is stopped, and the differential limitation is released.

The piston 65 is provided with an orifice 111 to discharge air mixed with oil while the hydraulic pressure is applied to the pressure chamber 71, and to appropriately discharge the oil.
The discharged oil lubricates the multi-plate clutch 57, the meshing parts of the gears, the sliding parts of the pinion gear 29 with the pinion shaft 25 and the spherical washer 39, and the differential case 5
It is discharged to the outside by a centrifugal force from the openings 113 and 115 provided in the differential carrier 3 and returns to the oil reservoir of the differential carrier 3.

As shown in FIGS. 1 and 4, the cover 13 of the differential case 5 is provided with oil scraping portions 117 and 119, and the differential carrier 3 is provided with an oil guide portion 121.

The oil scraping parts 117 and 119 have openings 123 and 125 and oil holding parts 127 and 129, respectively.
It has and. Opening 12 of oil scraping section 117
3 is open to one side in the rotational direction of the differential case 5, and the opening 125 of the oil scraping portion 119 is open in the rotational direction to the other side. Further, the oil guide portion 121 is arranged right above the opening portion 101 of the oil pocket 97, and
The reflective surfaces 131 and 133 are provided.

As shown in FIGS. 1 and 4, the oil scraping portions 117 and 119 are provided on the outermost side surface of the cover 13. When the differential case 5 rotates in the direction of arrow 135 in FIG. 4, the opening 123 of the oil scraping portion 117 pumps up oil from the oil reservoir of the differential carrier 3 and holds it in the oil holding portion 127, and the held oil is opened by centrifugal force. It is discharged from the part 123. The released oil hits the reflecting surface 131 of the oil guide portion 121 to change its direction,
The oil is supplied from the opening 101 of the oil pocket 97 to the internal oil sump. When the differential case 5 rotates in the direction of the arrow 137, the oil scraping portion 119 scrapes and discharges the oil, and the discharged oil hits the reflecting surface 133 of the oil guide portion 121 and enters the inside of the oil pocket 97. .

Thus, the oil scraping parts 117, 1
19 and the reflecting surfaces 131 and 133 of the oil guide portion 121 are provided corresponding to different rotation directions of the differential case 5, respectively, and therefore, regardless of whether the vehicle is moving forward or backward, these oil supply effects are provided. Oil pocket 9
Sufficient oil is always supplied to 7 and the oil level is always kept higher than the opening 85 (oil inlet of the gear pump 61).

Further, since the oil holding portions 127 and 129 are provided, the oil scraping amount of the oil scraping parts 117 and 119 increases, and the effect of supplying oil increases accordingly.

Further, since the oil guide portion 121 is arranged right above the opening portion 101 as described above, the oil adhering to the oil guide portion 121 drips into the oil pocket 97 to further improve the oil supply effect. I am raising.

Further, as shown in FIG. 4, the oil guide portion 121
Each of the reflecting surfaces 131 and 133 is composed of various gradients. Therefore, when the differential case 5 rotates at a high speed, the oil discharged from the oil scraping portions 117 and 119 is guided to the inside of the oil pocket 97 by hitting the slope of the base portion indicated by the arrow 139, and when the differential case 5 rotates at a low speed. The discharged oil hits the slope of the tip indicated by the arrow 141 and is guided into the oil pocket 97. In this way, even if the rotation speed (vehicle speed) of the differential case 5 changes over a wide range, the oil pocket 97 is always efficiently supplied with oil.

Thus, the differential device 1 is constructed.

As described above, in the differential device 1, since the gear pump 61 can directly suck the oil from the oil pocket 97, the oil passage is short and the passage resistance is small unlike the conventional example. Therefore, the oil suction efficiency is improved and the response of the differential limiting function is greatly improved. Moreover, the oil tube unlike the conventional example is unnecessary.

Further, the oil reservoir of the differential carrier 3 is sufficient if the oil level of the oil scraping portions 117, 119 of the differential case 5 or higher is sufficient, and it is not necessary to make it higher than the oil suction port (opening 85 etc.) of the gear pump 61. Therefore, the rotational resistance of the oil received by the differential device 1 is correspondingly reduced, and the fuel efficiency of the engine is improved.

Further, the oil pocket 97 is a differential case 5
Since the oil level thereof is substantially not affected by the inclination of the vehicle, the lateral G, etc., the gear pump 61 can always stably suck the oil regardless of the running condition or the road surface condition. And a stable differential limiting function can be obtained.

A vehicle using the differential device 1 is
The speed-sensitive differential limiting function prevents idling of the drive wheels on rough roads and improves drivability. Further, in a sharp turn at a high speed where a large differential rotation speed occurs, the attitude and behavior of the vehicle are stabilized by the differential limiting function of the differential device 1 which has a fast response to the differential rotation.
During gentle turning with a small differential rotation speed, the differential limiting force is relaxed, and smooth and stable turning travel is possible.

In the present invention, the differential mechanism is not limited to the bevel gear type, and for example, a torque sensitive differential limiting function is obtained by utilizing the tooth flank friction force of the gear or the friction resistance between the gear and the differential case. It may be a dynamic mechanism. By using such a differential mechanism, it is possible to obtain a differential device having not only the torque sensitive differential limiting function but also the speed sensitive differential limiting function by the friction clutch and the oil pump as described above.

Further, the friction clutch is not limited to the multi-plate clutch, but may be, for example, a cone clutch.

The differential device of the present invention is a differential device for distributing front diff (front wheel side axle diff), rear diff (rear wheel side axle diff) and center diff (engine driving force to front and rear wheels). ).

[0070]

In the differential device according to each of the claims, the oil pump is driven by the differential rotation, the hydraulic actuator is actuated, the friction clutch is pressed, and the differential is limited to provide a speed-sensitive differential limiting function. obtain.

When the differential case rotates, the oil scraping portion scrapes up the oil from the oil sump of the housing and discharges the oil. The discharged oil hits the oil guide portion of the housing and contacts an oil pocket provided in the differential case. enter. Thus, as long as the differential case is rotating, oil is supplied to the oil pocket to keep the oil level higher than the oil intake port of the differential case. The oil pump draws oil directly from this oil pocket.

As described above, unlike the conventional example, since the oil passage of the oil pump is short and the passage resistance is small, the oil suction efficiency is improved and the response of the differential limiting function is greatly improved. Further, since it is not necessary to raise the oil level of the housing higher than the oil intake port of the differential case, the rotational resistance of the oil received by the differential device is reduced by that much, and the fuel efficiency of the engine is improved.

Further, since the oil pocket is arranged in close contact with the differential case and the oil level thereof is not substantially affected by the inclination of the vehicle, the lateral G, etc., the oil pocket is not affected by the running condition or the road surface condition of the vehicle. The pump can always suck oil stably, and a stable differential limiting function can be obtained.

Further, unlike the conventional example, the oil tube is unnecessary, and the number of parts is small.

A differential device according to a second aspect of the present invention is the differential device according to the first aspect, wherein the oil scraping portion is constituted by an opening portion for discharging the oil toward the oil holding portion and the oil guide portion, and the differential device according to the third aspect. As for the device, in the differential device of claim 1 or 2, the oil scraping portion is integrally formed with the differential case, so that the response of the differential limiting function and the engine fuel consumption are the same as those of the differential device of claim 1 or 2. Improved, stable differential limiting function is obtained regardless of running conditions and road conditions, and the number of parts is small.

In addition to this, in the structure of the second aspect, by providing the oil holding portion, the oil scraping efficiency of the oil scraping portion is improved, and the oil supply amount to the oil pocket is increased. Further, in the configuration of claim 3, the oil scraping portion can be processed integrally with the differential case (for example, casting processing), so that the cost is low.

A differential device according to a fourth aspect of the present invention is the differential device according to the first, second or third aspect, in which the reflecting surface of the oil guide portion is provided with different gradients corresponding to the angle of flight of the oil, and a wide rotation speed of the differential case. By configuring so that the oil can be effectively guided into the oil pocket within the range, the response of the differential limiting function and the engine fuel consumption are improved and the running is performed, as in the differential device according to claim 1, 2 or 3. A stable differential limiting function can be obtained regardless of conditions and the number of parts is small.

Further, even if the vehicle speed changes in a wide range, the oil is always effectively supplied to the oil pocket, and the above-mentioned respective effects can be stably obtained.

The differential device according to claim 5 is the differential device according to claim 1, 2, 3 or 4.
By disposing the oil guide portion above the oil pocket in the direction of gravity, the response of the differential limiting function and the engine fuel consumption are improved, as in the differential device according to claim 1, 2, 3 or 4, and it is suitable for running conditions. Regardless, a stable differential limiting function can be obtained at all times, and the number of parts is small.

Furthermore, the oil guide portion not only reflects the flying oil but also drops the oil in the oil pocket below in the direction of gravity, so that the effect of supplying oil to the oil pocket is further improved, and the oil is stably fed as described above. Each effect is obtained.

A differential device according to a sixth aspect is the differential device according to the first, second, third, fourth or fifth aspect, wherein an oil scraping portion and a reflecting surface of the oil guide portion corresponding to both rotational directions of the differential case are provided. As a result, similarly to the differential device according to claim 1, 2, 3, 4, or 5, the response of the differential limiting function and the engine fuel consumption are improved, and the differential limiting function that is always stable regardless of the driving conditions is provided. The number of parts obtained is small.

Furthermore, since the oil is constantly supplied to the oil pocket regardless of whether the vehicle is moving forward or backward, the above-described effects can be stably obtained.

[Brief description of drawings]

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

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

FIG. 3 is a perspective view showing a metal fitting or the like for fixing the oil pocket to the stationary side in the embodiment of FIG.

FIG. 4 is a perspective view showing a positional relationship between an oil pocket, an oil scraping portion, an oil guide portion, and the like in the embodiment of FIG.

FIG. 5 is a cross-sectional view of a conventional example.

[Explanation of symbols]

 1 Differential Device 3 Differential Carrier (Housing) 5 Differential Case 53 Differential Mechanism 57 Multiple Disc Clutch (Friction Clutch) 59 Hydraulic Actuator 61 Gear Pump (Oil Pump) 85 Opening (Oil Suction Port) 97 Oil Pocket 117, 119 Oil Raising Part 121 Oil Guide part 123, 125 Opening part 127, 129 Oil holding part 131, 133 Reflecting surface

Claims (6)

[Claims] 1. A housing having an oil sump, a differential case disposed inside the housing and rotationally driven by a driving force of an engine, a differential mechanism disposed in the differential case, and a differential mechanism limiting the differential mechanism. Friction clutch,
An oil pump that is driven by the differential rotation of the differential mechanism and sucks oil from an oil suction port that opens in the differential case, a hydraulic actuator that receives the oil pressure of the oil pump and presses and engages the friction clutch, and a side surface of the differential case. Is fixed to the housing side in a liquid-tight and slidable contact with the housing, and an oil pocket is formed inside which forms an oil reservoir for keeping the oil level above the oil intake port, and a housing provided on the side surface of the differential case. A differential having an oil scraping portion for scraping oil from the oil sump, and an oil guide portion provided on the housing side for guiding the scraped oil to a reflecting surface and guiding it to the oil sump of the oil pocket. apparatus. 2. The differential device according to claim 1, wherein the oil scraping portion has an oil holding portion and an opening for scraping the oil and discharging the oil toward the oil guide portion. 3. The differential device according to claim 1, wherein the oil scraping portion is formed integrally with the differential case. 4. The reflecting surface of the oil guide portion corresponds to the angle of flight of the oil, which changes depending on the rotation speed of the differential case,
4. The differential device according to claim 1, 2 or 3, wherein the differential device has different gradients for guiding the oil to the oil sump of the oil pocket over a wide rotation speed range. 5. The differential device according to claim 1, 2, 3, or 4, wherein the oil guide portion is arranged above the oil pocket in the direction of gravity and drops the splashed oil into the oil reservoir of the oil pocket. 6. The oil scraping portion corresponding to each of the two rotation directions of the differential case is provided, and the oil guide portion has a reflecting surface corresponding to each of the oil scraping portions for each direction. 3, 4 or 5 differential devices.