JPH04254046A - Breather device for transfer - Google Patents

Abstract

PURPOSE:To improve a reserve effect by forming an opening face, receding diagonally from the oil upstream side to the oil downstream side, at the breather pipe end part positioned in the internal space of a transfer case in a transfer breather device for a four-wheel drive vehicle. CONSTITUTION:The end part 48b, positioned in the internal space S of a transfer case 40, of a breather pipe 48 is formed into a diagonal opening face 56 receding toward the oil downstream side face 48c from the oil upstream side face 48a. The angle alpha of this opening face 56 to the oil flow direction X is set to be more than 45 deg., and bubbles in the oil are concentrated. A flow deflecting rib 68 of the specified height is further provided on the inner wall surface 66 of the transfer case 40, in an oil flow downstream side position by the distance L from the center C of the breather pipe 48. Oil is thereby prevented from flowing directly into the diagonal opening face 56 at the contraflow time of the oil flow.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transfer breather device, and more particularly to a transfer breather device that has a simple structure and can improve breather efficiency without causing oil to flow out.

0002

[Prior Art] A four-wheel drive vehicle has a transmission that appropriately takes out the driving force generated by the internal combustion engine depending on the driving condition, and a transmission that distributes the driving force from the transmission to either the front or rear wheels. A transfer is provided. In this transfer, a breather mechanism is provided to adjust the pressure difference between the inside and outside of the transfer case.

An example of a transfer breather device is shown in FIG. 11. In FIG. 11, a pipe mounting hole 104 is formed in the transfer case 102, and a breather pipe 106 is formed in the pipe mounting hole 104.
is provided so as not to protrude from the inner wall surface 108 of the transfer case 102 into the internal space S, and air bubbles in the oil are flowed outside from the breather pipe 106.

Further, as shown in FIG. 12, a pipe mounting hole 204 is formed in the transfer case 202, and a breather pipe 206 is provided in the pipe mounting hole 204 so as not to protrude from the inner wall surface 208 of the transfer case 202 into the internal space S. A rib 210 of a predetermined height is provided protruding from the inner wall surface 208 of the transfer case 40 on the upstream side of the oil flow from the breather pipe 206, and a holed plate 212 surrounding the inlet portion of the breather pipe 206 is provided on the rib 210. Some are attached with screws 214 to form a breather space 216 to prevent oil from flowing directly into the breather pipe 206.

Furthermore, as shown in FIG. 13, the transfer case 302 has a pipe attachment protrusion 304 formed by protruding a part of the transfer case 302 outward, and the pipe attachment protrusion 304 connects the interior space S. A breather space 306 that communicates with the pipe mounting protrusion 304 is formed.
A pipe mounting hole 308 is formed in the pipe mounting hole 30.
Attach the breather pipe 310 to the breather space 30.
6 prevents oil from flowing into the breather pipe 310.

Further, a breather device for a transmission is disclosed in, for example, Japanese Utility Model Application Publication No. 54-88728. The device described in this publication has a shroud extending substantially vertically from the final reduction gear box to prevent oil splashed by the gears in the final reduction gear box from landing on the air breather and the upper surface of the ribs.

[0007]

However, the breather device shown in FIG. 11 has the disadvantage that oil flows directly into the breather pipe, and the oil flows out from the breather pipe.

Furthermore, in the breather device shown in FIG. 12, it is necessary to form a breather space in the internal space of the transfer case, which leads to an increase in the size of the transfer case, and it is necessary to attach a plate with holes to the screws. , there was a disadvantage that the configuration became complicated.

Furthermore, in the breather device shown in FIG. 13, a part of the transfer case must protrude outward to form a breather space, which restricts the method of die casting when manufacturing the transfer case. There was an inconvenience.

0010

[Means for Solving the Problems] Therefore, in order to eliminate the above-mentioned disadvantages, the present invention provides a transfer that distributes the driving force from the transmission to either the front or rear wheels, in which one end side is located in the internal space of the transfer case. A breather pipe is provided in the transfer case, the other end of which is located approximately perpendicular to the oil flow and which is located outside of the transfer case, and one end of the breather pipe located in the internal space of the transfer case is provided with an oil upstream side. A diagonal opening surface is formed at a predetermined angle to collect air bubbles in the oil from the tip of the side surface to the downstream side surface of the oil, and an oil flow is formed on the inner circumferential surface of the transfer case on the downstream side of the oil flow from the breather pipe. The present invention is characterized in that a flow deflection member having a predetermined height is provided to prevent the oil flow from directly flowing into the diagonal opening surface when the oil flow is reversed.

[0011]

[Operation] According to the structure of the present invention, when oil flows to the breather pipe side in the transfer case, oil turbulence is generated on the downstream side of this diagonal opening surface by the diagonal opening surface of the breather pipe. Air bubbles are collected on the downstream side of this oblique opening surface, and the air bubbles are smoothly discharged from the breather pipe to the outside. At this time, since the diagonal opening surface of the breather pipe is not oriented toward the upstream side of the oil flow, oil does not flow out from the breather pipe.

Furthermore, when the oil flow is in the opposite direction, the flow of oil is deflected by the flow deflecting member, so that the oil does not flow directly into the diagonal opening surface, and the oil flows out from the breather pipe. can be effectively prevented.

Furthermore, since the breather pipe can be post-processed from the outside of the transfer case, processing and assembly efficiency can be improved.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the present invention will be described in detail and specifically below with reference to the drawings.

1 to 10 show embodiments of the invention. In FIG. 10, 2 is a transaxle mounted on a four-wheel drive vehicle (not shown). The transaxle 2 includes a clutch section 4 that connects and disconnects driving force from an internal combustion engine (not shown) installed horizontally at the front of the vehicle body, a main shaft 6 provided with a plurality of gear trains, and a main shaft 6 provided with a plurality of gear trains. A speed change gear section 10 having a counter shaft 8 provided with a gear train, a reduction drive gear 14 of a reduction gear mechanism 12 provided on the counter shaft 8, and a reduction drive gear 214 degrees meshed with the reduction drive gear 214 and fixed to the differential case 16. A front differential section 20 connected to the transmission gear section 10 by a reduction driven gear 18
and a transfer intermediate shaft 24 fixed to the transfer drive gear 22 that meshes with the reduction driven gear 18.
and a transfer section 26 having a.

A right axle 28-1 connected to a right wheel (not shown) and a left axle 28-2 connected to a left wheel (not shown) are connected to the front differential section 20.

In the transfer section 26, a transfer bevel pinion gear 32 meshes with a transfer drive bevel gear 30 provided on the transfer intermediate shaft 24, and the transfer bevel pinion gear 32 is connected to a transaxle substantially perpendicular to the transfer intermediate shaft 24. The transfer pinion shaft 24 is configured to be fixedly attached to the transfer pinion shaft 24, which is the output shaft of the motor. A propulsion shaft connecting flange 36 is fixed to the end of the transfer pinion shaft 34 with a nut 38 .

The transfer intermediate shaft 24 has one end rotatably supported on the position side of the transfer case 40, an intermediate portion rotatably supported by an intermediate portion of the transfer case 40 via an oil seal body 42, and further , the other end side is rotatably supported by an end case 44 attached to the other side of the transfer case 40.

The transfer case 40 is provided with a breather mechanism 46 that adjusts the pressure difference between the inside and outside of the transfer case 40.

The breather mechanism 46 includes a breather pipe 48 and a breather hose 50. That is, Figure 2
, 3, a breather pipe 48 is attached to the pipe fixing part 52 at the middle and upper part of the transfer case 40.
A pipe mounting hole 54 is formed in which the breather pipe 48 is mounted, and one end of the breather pipe 48 is positioned in the internal space S of the transfer case 40 and mounted in the pipe mounting hole 54.

At one end of this breather pipe 48, as shown in FIGS. 3 and 5, there is a tip 48b of an oil upstream side surface 48a.
A diagonal opening surface 56 is formed that recedes from the oil downstream side surface 48C. That is, this oblique opening surface 56 is formed at an acute angle (α) of 45 degrees or more with respect to the horizontal line X in the same direction as the oil flow in order to collect air bubbles in the oil.

[0022] On the outer surface of the breather pipe 48, in order to fix the breather pipe 48 at a predetermined position where the diagonal opening surface 56 of the breather pipe 48 is immersed in the oil, a fixing plate is provided on the outer surface of the breather pipe 48 in contact with the pipe fixing portion 52 of the transfer case 40. A flange 58 is attached.

One end of a breather case 50 is connected to the other end of the breather pipe 48 protruding to the outside of the transfer case 40. As shown in FIG. 9, this breather hose 50 is held in the transfer case 40 by an intermediate holder 60 at the middle, and held in the transmission case 64 by an end holder 62 at the other end to be exposed to the atmosphere.

As shown in FIGS. 2 to 4, the inner wall surface 66 of the transfer case 40 at a distance L downstream of the center C of the breather pipe 48 has an oil flow in the opposite direction. When the oil flow reaches the diagonal opening surface 56
In order to prevent the flow from flowing directly into the flow, a rib 68, which is a flow deflecting member, is provided with a predetermined height H (for example, 5 mm). This rib 68 is used when the vehicle is traveling in reverse.
Although the oil flow changes in the opposite direction, since the rotation speed of the gear is low and the oil flow is gentle, this level of height H can prevent the oil flow from directly flowing into the diagonal opening surface 56.

Next, the operation of this embodiment will be explained.

When the vehicle is moving forward, oil flow occurs in the forward direction, that is from left to right in FIG.
The oil flows so as to wrap around the breather pipe 48, and as a result, as shown in FIG. The air bubbles in the oil are concentrated, and the air bubbles smoothly flow into the breather pipe 48 and the breather hose 5.
0 and is easily discharged to the outside. Moreover, at this time, since the oil flow does not directly flow into the diagonal opening surface 56,
Oil does not flow into the breather pipe 48,
Oil outflow can be effectively prevented.

Furthermore, when the vehicle reverses (reverses), the gear rotates in the opposite direction, so the oil flow is also changed to the opposite direction, and the oil flows from the rib 68 side. but,
Since this oil flow is slow due to the low rotation of the gear, its direction is easily deflected by the presence of the ribs 68, and the oil does not flow directly into the diagonal opening surface 56. Therefore, the oil flows into the breather pipe 48.
This effectively prevents oil from flowing into the interior of the tank.

As a result, by simply forming the diagonal opening surface 56 in the breather pipe 48, the breather effect can be improved while preventing oil outflow, and the transfer case 40 does not require any special processing, and the structure can be improved. This is simple, and since the breather pipe 48 can be post-processed from the outside of the transfer case 40, processing and assembling properties can be improved.

[0029]

As is clear from the above detailed description, according to the present invention, there is provided a breather whose one end side is located substantially perpendicular to the oil flow in the internal space of the transfer case, and whose other end side is located outside the transfer case. A pipe is provided in the transfer case, and one end of the breather pipe located in the internal space of the transfer case is formed with an oblique opening surface that recedes at a predetermined angle from the tip of the oil upstream side surface to the oil downstream side surface to collect air bubbles in the oil. In addition, a flow deflection member of a predetermined height is installed on the inner peripheral surface of the transfer case on the downstream side of the oil flow from the breather pipe to prevent the oil flow from directly flowing into the diagonal opening surface when the oil flow is reversed. By providing this structure, air bubbles in the oil flowing in the transfer case are collected on the downstream side of the diagonal opening surface and flowed away from the breather pipe to the outside, improving the breather effect and preventing oil from flowing directly into the diagonal opening surface. Therefore, oil can be prevented from flowing out from the breather pipe. In addition, when the oil flow is in the opposite direction, the flow deflection member changes the oil flow, prevents the oil from flowing directly into the diagonal opening surface, and effectively prevents the oil from flowing out from the breather pipe. can be prevented. Furthermore, since the breather pipe can be post-processed from the outside of the transfer case, processing and assembly efficiency can be improved.

[Brief explanation of the drawing]

FIG. 1 is a side view of a transfer section provided with a breather device.

FIG. 2 is a sectional view of the breather device.

FIG. 3 is an enlarged sectional view of the breather device in FIG. 2;

FIG. 4 is a sectional view from the right side in FIG. 2;

FIG. 5 is a cross-sectional view of the breather pipe.

FIG. 6 is a bottom view of the breather pipe.

FIG. 7 is a side view showing the state of oil flow.

FIG. 8 is a rear view showing the state of oil flow.

FIG. 9 is a plan view of the transaxle.

FIG. 10 is a cross-sectional view of the transaxle.

FIG. 11 is a sectional view of a conventional breather device.

FIG. 12 is a sectional view of another conventional breather device.

FIG. 13 is a sectional view of still another conventional breather device.

[Explanation of symbols]

2 Transaxle 24 Transfer axis 26 Transfer section 40 Transfer case 46 Breather mechanism 48 Breather pipe 50 Breather hose 56 Diagonal opening surface 68 Rib

Claims (1)

[Claims] Claim 1: In a transfer that distributes driving force from a transmission to either front or rear wheels, one end is located substantially perpendicular to the oil flow in the internal space of the transfer case, and the other end is located outside the transfer case. A breather pipe located in the transfer case is provided at one end of the breather pipe located in the internal space of the transfer case, and a predetermined angle is provided at one end of the breather pipe located in the internal space of the transfer case to collect air bubbles in the oil from the tip of the oil upstream side surface to the oil downstream side surface. The inner peripheral surface of the transfer case on the downstream side of the oil flow from the breather pipe is configured to form a diagonal opening surface that recedes at the direction of the oil flow, and to prevent the oil flow from directly flowing into the diagonal opening surface when the oil flow is in the opposite direction. A transfer breather device comprising a flow deflection member having a predetermined height for preventing flow.