JP6488158B2 - Differential equipment - Google Patents

Description

  The present invention relates to a differential apparatus including a baffle plate.

2. Description of the Related Art Conventionally, as a differential device for a vehicle, one having a baffle plate for reducing spin loss is known (see, for example, Patent Documents 1 and 2).
The baffle plate is provided so as to cover a lower portion of a ring gear (final driven gear) fixed to a differential case (hereinafter referred to as “difference case”) that accommodates the differential gear mechanism, with a gap interposed therebetween.
Therefore, the rotation of the ring gear makes it difficult for the lubricating oil to enter the gap with the baffle plate, and the amount of inflow oil is less than the amount of discharged oil that the ring gear scrapes from the baffle plate. Thereby, the stirring resistance of the lubricating oil with respect to the ring gear is reduced, and consequently, the spin loss is reduced.

Patent No. 5534603 International Publication No. 2014/017301

By the way, the supply of the lubricating oil to the differential gear mechanism in the differential case is mainly performed by introducing the lubricating oil that has been lifted up by the ring gear from the hole of the differential case.
However, in the conventional differential device, since the amount of oil discharged from the baffle plate increases as described above, the amount of lubricating oil that the ring gear lifts from the baffle plate decreases. As a result, the amount of lubricating oil supplied into the differential case is also reduced, and the seizure resistance of the differential gear mechanism is reduced.

  The present invention has been made to solve the above-described problems, and an object thereof is to improve the seizure resistance of a differential gear mechanism.

In order to achieve the above object, the invention according to claim 1 includes a case member that accommodates a differential gear mechanism therein and is rotatably supported about a substantially horizontal central axis.
A ring gear fixed concentrically to the case member and rotating the case member in a predetermined rotation direction;
A baffle plate provided to cover the lower portion of the case member while interposing a gap between the case member and the case member;
A differential device comprising:
The case member communicates the inside and the outside of the case member, and has a hole formed at a position where the case member protrudes and appears from the inside of the baffle plate as the case member rotates.
The baffle plate is
The gap between the case member is provided so that the outlet side gap on the downstream side is narrower than the inlet side gap on the upstream side in the rotation direction , and
The central axis of the inner peripheral surface along the axial direction is relative to the central axis of the case member so that a gap between the case member and the case member gradually decreases from the upstream side to the downstream side in the rotation direction. It is eccentric in the horizontal direction on the upstream side in the rotational direction .

According to a second aspect of the invention, in the differential apparatus according to claim 1,
The case member accommodates the differential gear mechanism, and has a case main body having the central shaft and the hole,
The ring gear is fixed to a portion of the case member on one side in the axial direction from the case body,
The baffle plate has a gear covering portion that covers a lower portion of the ring gear, and a case covering portion that covers a lower portion of the case main body portion of the case member,
The gear covering portion is provided such that a gap between the ring gear and the ring gear is substantially constant along a circumferential direction,
The case covering portion is provided such that a gap between the case body portion and the case main body portion is narrower in the outlet side gap than in the inlet side gap.

According to the first aspect of the present invention, the baffle plate is provided so as to cover the lower part of the case member that accommodates the differential gear mechanism, and the gap between the baffle plate and the case member is the rotation direction of the case member. The outlet side gap on the downstream side is narrower than the inlet side gap on the upstream side.
Thereby, the amount of lubricating oil flowing in from the inlet side gap is larger than the amount of lubricating oil discharged from the outlet side gap to the outside of the baffle plate as the case member rotates. As a result, the lubricating oil is likely to be accumulated in the baffle plate, so that the accumulated lubricating oil is suitable for the case member so that it can be scooped up from the hole that protrudes from the baffle plate as the case member rotates. To be introduced.
Therefore, lubricating oil can be suitably supplied to the differential gear mechanism in the case member, and the seizure resistance of the differential gear mechanism can be improved.

Further, as the gap between the baffle plate and the case member becomes gradually narrower toward the downstream side from the upstream side in the rotation direction, the center axis of the inner peripheral surface of the baffle plate, horizontal with respect to the central axis of the case member Is eccentric to the upstream in the direction of rotation.
As a result, the lubricating oil flows smoothly into the baffle plate and is more likely to accumulate.
Accordingly, the lubricating oil can be more suitably supplied to the differential gear mechanism in the case member, and the seizure resistance of the differential gear mechanism can be further improved.

According to the second aspect of the present invention, the gear covering portion that covers the lower portion of the ring gear in the baffle plate is provided so that the gap between the ring gear and the ring gear is substantially constant along the circumferential direction. The case covering portion that covers the lower portion of the case main body portion in which the dynamic gear mechanism is housed has a narrower gap between the case main body portion and the downstream outlet side gap than the upstream inlet clearance in the rotational direction. It is provided as follows.
Thereby, in the gear covering part of the baffle plate, the inflow oil amount is reduced with respect to the discharged oil amount to suitably reduce the agitation resistance of the lubricating oil with respect to the ring gear. Lubricating oil can be suitably supplied to the differential gear mechanism in the case member.
Therefore, the seizure resistance of the differential gear mechanism can be improved while suitably reducing the spin loss.

It is a perspective view of a differential device in an embodiment. It is a side view of a differential device in an embodiment. It is sectional drawing of the differential apparatus in the III-III line | wire of FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  1 and 2 are a perspective view and a side view of the differential device 1 in the present embodiment, and FIG. 3 is a cross-sectional view of the differential device 1 taken along line III-III in FIG. However, in FIG. 3, the differential case 2 mentioned later has shown the state rotated 90 degrees from the state of FIG.

  As shown in FIGS. 1 and 2, the differential device 1 is a differential device for a vehicle, and includes a differential case (hereinafter referred to as “diff case”) 2, a ring gear 3, and a baffle plate inside a housing (not shown). 4 is provided.

  Among these, the differential case 2 has a case main body 21 whose inside is a differential chamber 21a (see FIG. 3). A bevel gear type differential gear mechanism (not shown) formed by meshing each pair of side gears and pinion gears is accommodated in the differential chamber 21a.

  The case main body 21 is provided with two cylindrical extending portions 22 and 22 extending from the case main body 21 to both sides along a substantially horizontal central axis Ax passing through the center of the differential chamber 21a. Yes. The outer peripheral surface of each extending portion 22 is supported by the bearing 5, so that the differential case 2 can rotate about the central axis Ax. Each extension 22 has a cylindrical interior communicating with the inside of the differential chamber 21a, and a drive shaft (not shown) connected to a side gear in the differential chamber 21a is inserted into the interior of the cylinder.

  Of the case main body 21, it is an end portion on one side (left side in FIG. 2) in the direction along the central axis Ax (hereinafter referred to as “axial direction”), and the base end of the extension portion 22 on the one side An annular plate-like flange portion 23 to which the ring gear 3 is attached projects from the case so as to protrude from the case main body portion 21 in the outer diameter direction.

The case body 21 is formed with two lubricating oil introduction holes 21b and 21b and two bearing holes 21c and 21c.
Among these, the two lubricating oil introduction holes 21b and 21b are for introducing the lubricating oil into the differential chamber 21a from the outside, and are formed at positions that are axially symmetric with each other along the direction orthogonal to the central axis Ax. Thus, the inside and the outside of the case main body 21 are communicated. Further, the two lubricating oil introduction holes 21 b and 21 b are formed at positions where the lube case 2 protrudes from the case covering portion 42 of the baffle plate 4 to be described later that covers the substantially lower half portion of the case main body portion 21 as the differential case 2 rotates. ing.
On the other hand, the two bearing holes 21c and 21c support the shaft (not shown) of the pinion gear in the differential chamber 21a, and any of the direction along the two lubricating oil introduction holes 21b and 21b and the central axis Ax. Both are formed in positions that are axially symmetric with each other along the orthogonal direction.

  The ring gear 3 is a final driven gear that meshes with a final drive gear (not shown), and its central axis is the central axis of the differential case 2 (case main body 21) with its tooth surface facing one side in the axial direction (left side in FIG. 2). It is fixed to the flange portion 23 of the differential case 2 in a state where it matches with Ax. Therefore, the ring gear 3 integrally rotates the differential case 2 in the rotation direction R (see FIG. 3) as the final drive gear rotates. As a result, the output of the final drive gear is transmitted to the drive shaft connected to the side gear of the differential gear mechanism.

  The baffle plate 4 is a bowl-shaped lubricating oil containing part that opens upward, and is disposed so as to cover the substantially lower half of the differential case 2 and the ring gear 3 while interposing a gap between the differential case 2 and the ring gear 3. And fixed to a housing (not shown). More specifically, the baffle plate 4 includes a gear cover 41 that covers a substantially lower half of the ring gear 3 and a case cover 42 that covers a substantially lower half of the case main body 21 of the differential case 2. ing.

Among these, as shown in FIG. 3, the gear covering portion 41 is formed in a shape that substantially follows the outer shape of the ring gear 3, and the central axis of the inner and outer peripheral surfaces is the central axis Ax of the case body portion 21 (that is, the ring gear 3 Is substantially coincident with the central axis of Therefore, the gap between the gear covering portion 41 and the ring gear 3 is substantially constant over the entire area in the circumferential direction.
In addition, although the notch is formed in the gear coating | coated part 41 in this embodiment in a part of side wall located in the outer diameter direction of the ring gear 3 (refer FIG.1 and FIG.2), this notch is not shown in figure. This is for avoiding interference with other parts, and need not be formed.

On the other hand, the case covering portion 42 is formed in a shape that substantially follows the outer shape of the ring gear 3, and the central axis 42 a of the inner and outer peripheral surfaces along the axial direction is eccentric with respect to the central axis Ax of the case main body portion 21. . More specifically, in the case covering portion 42, the central axis 42a of the inner and outer peripheral surfaces is slightly lower than the central axis Ax of the case main body portion 21 and upstream in the rotational direction R of the ring gear 3 in the horizontal direction (FIG. 3). On the left side). Therefore, the clearance CL between the outer peripheral surface of the case main body 21 (the outer shape locus L during rotation) and the inner peripheral surface of the case covering portion 42 gradually increases from the upstream side in the rotation direction R of the differential case 2 toward the downstream side. It is narrower.
However, this gap CL is the outlet side gap CL ₂ on the downstream side in the rotation direction R (most downstream portion) may be narrower than the inlet side gap CL ₁ of the upstream side (most upstream portion), the rotational direction R It does not have to be gradually narrowed from the upstream side toward the downstream side. In the present embodiment, the clearance CL ₂ on the outlet side of the clearance CL is set to about 1.5 mm as the minimum clearance where the baffle plate 4 and the case main body 21 do not contact each other in consideration of assembly accuracy and the like. Yes.

Next, a description will be given of the supply of lubricating oil to the differential gear mechanism in the differential chamber 21a in the differential device 1. FIG.
In the differential device 1, when the ring gear 3 and the differential case 2 rotate in the rotation direction R along with the rotation of the final drive gear, the lubricating oil stored inside the housing (not shown) is lifted up by the ring gear 3, Is housed in.

  At this time, since the rotation of the ring gear 3 makes it difficult for the lubricating oil to enter the gear covering portion 41 of the baffle plate 4, the amount of discharged oil that the ring gear 3 scrapes out from the gear covering portion 41 is within the gear covering portion 41. The amount of oil flowing into Thereby, the stirring resistance of the lubricating oil with respect to the ring gear 3 is reduced, and consequently the spin loss is reduced.

  Lubricating oil pumped up by the ring gear 3 lubricates the meshing portion between the final drive gear and the ring gear 3 itself, and in the differential chamber 21a through the two lubricating oil introduction holes 21b and 21b of the differential case 2 (case body portion 21). Introduced to lubricate the differential gear mechanism.

Further, the differential gear mechanism in the differential chamber 21 a is also lubricated by the lubricating oil accumulated in the case covering portion 42 of the baffle plate 4. Specifically, the case main body is configured such that the lubricating oil accumulated in the case covering portion 42 is scooped up from the two lubricating oil introduction holes 21 b and 21 b that appear and disappear from the case covering portion 42 as the differential case 2 rotates. It is introduced into the differential chamber 21a of the part 21 and lubricates the differential gear mechanism.
At this time, the clearance CL between the case main body portion 21 and the case covering portion 42 is such that the outlet-side clearance CL ₂ is narrower than the inlet-side clearance CL _1. towards the _second lubricating oil amount flowing from the inlet side gap CL ₁ than the lubricating oil amount discharged to the outside the gap CL (case cover 42) increases. As a result, the lubricating oil tends to be accumulated in the case covering portion 42, and as a result, the lubricating oil is easily introduced into the differential chamber 21a.

  In this way, the differential gear mechanism in the differential chamber 21a is also caused by the lubricating oil accumulated in the case covering portion 42 of the baffle plate 4 in addition to the lubricating oil that the ring gear 3 lifts from the gear covering portion 41 of the baffle plate 4. It is suitably lubricated and seizure is prevented.

As described above, according to the differential device 1 of the present embodiment, the baffle plate 4 (case covering portion 42) is provided so as to cover the lower portion of the differential case 2 (case main body portion 21) that houses the differential gear mechanism. The clearance CL between the case covering portion 42 and the case main body 21 is narrower in the downstream outlet side clearance CL ₂ than the upstream inlet clearance CL _{1 in} the rotational direction R of the differential case 2. .
As a result, the amount of lubricating oil flowing from the inlet side gap CL ₁ becomes larger than the amount of lubricating oil discharged from the outlet side gap CL ₂ to the outside of the case covering portion 42 as the differential case 2 rotates. As a result, since the lubricating oil tends to be accumulated in the case covering portion 42, the accumulated lubricating oil is scooped up from the lubricating oil introduction hole 21 b that appears and disappears from the case covering portion 42 as the differential case 2 rotates. Oil is preferably introduced into the differential chamber 21 a in the case body 21.
Therefore, the lubricating oil can be suitably supplied to the differential gear mechanism in the differential chamber 21a, and the seizure resistance of the differential gear mechanism can be improved.

Further, the gap of the case covering portion 42 is set so that the gap CL between the baffle plate 4 (case covering portion 42) and the differential case 2 (case main body portion 21) gradually decreases from the upstream side in the rotation direction R toward the downstream side. The central axis 42a of the inner peripheral surface is eccentric to the upstream side in the rotational direction R in the horizontal direction with respect to the central axis Ax of the case body 21.
As a result, the lubricating oil flows smoothly into the case covering portion 42 and is more likely to accumulate.
Accordingly, the lubricating oil can be more suitably supplied to the differential gear mechanism in the differential chamber 21a, and the seizure resistance of the differential gear mechanism can be further improved.

In addition, the gear covering portion 41 that covers the lower portion of the ring gear 3 in the baffle plate 4 is provided so that a gap between the ring gear 3 and the ring gear 3 is substantially constant along the circumferential direction, while the differential gear mechanism is accommodated. The case covering portion 42 that covers the lower portion of the case main body portion 21 has a clearance CL between the case main body portion 21 and the outlet side clearance CL _{2 that} is downstream of the upstream side inlet clearance CL _{1 in the} rotation direction R. It is provided to be narrower.
Thereby, in the gear covering portion 41 of the baffle plate 4, the inflow oil amount is reduced with respect to the discharged oil amount to suitably reduce the agitation resistance of the lubricating oil to the ring gear 3, and in the one case covering portion 42. As described above, the lubricating oil can be suitably supplied to the differential gear mechanism in the differential chamber 21a.
Therefore, the seizure resistance of the differential gear mechanism can be improved while suitably reducing the spin loss.

  The embodiments to which the present invention can be applied are not limited to the above-described embodiments, and can be appropriately changed without departing from the spirit of the present invention.

  For example, in the above embodiment, only the case covering portion 42 of the baffle plate 4 is eccentric with respect to the central axis Ax of the differential case 2, but the gear covering portion 41 is also eccentric in the same manner as the case covering portion 42. It is good to be.

  Further, the baffle plate 4 covers substantially the lower half of the differential case 2 and the ring gear 3, but it is only necessary to cover the lower portions thereof.

1 Differential device 2 Differential case (case member)
21 Case body 21a Differential chamber 21b Lubricating oil introduction hole (hole)
Ax Center axis L Outline locus 3 Ring gear 4 Baffle plate 41 Gear cover part 42 Case cover part 42a Central axis CL gap CL ₁ inlet side gap CL ₂ outlet side gap R Rotation direction

Claims (2)

A case member that accommodates the differential gear mechanism therein and is supported so as to be rotatable about a substantially horizontal central axis;
A ring gear fixed concentrically to the case member and rotating the case member in a predetermined rotation direction;
A baffle plate provided to cover the lower portion of the case member while interposing a gap between the case member and the case member;
A differential device comprising:
The case member communicates the inside and the outside of the case member, and has a hole formed at a position where the case member protrudes and appears from the inside of the baffle plate as the case member rotates.
The baffle plate is
The gap between the case member is provided so that the outlet side gap on the downstream side is narrower than the inlet side gap on the upstream side in the rotation direction , and
The central axis of the inner peripheral surface along the axial direction is relative to the central axis of the case member so that a gap between the case member and the case member gradually decreases from the upstream side to the downstream side in the rotation direction. A differential device characterized by being eccentric in the horizontal direction upstream in the rotational direction . The case member accommodates the differential gear mechanism, and has a case main body having the central shaft and the hole,
The ring gear is fixed to a portion of the case member on one side in the axial direction from the case body,
The baffle plate has a gear covering portion that covers a lower portion of the ring gear, and a case covering portion that covers a lower portion of the case main body portion of the case member,
The gear covering portion is provided such that a gap between the ring gear and the ring gear is substantially constant along a circumferential direction,
2. The differential according to claim 1 , wherein the case covering portion is provided such that a gap between the case covering portion and the case main body portion is narrower in the outlet side gap than in the inlet side gap. apparatus.

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