JPH11348586A - Transfer of four wheel drive - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make common use of a transmission part between two wheel drive and four wheel drive by providing a spline fitting part to spline-fit a transfer shaft and a transmission output shaft to an inner circumferential part of an end part of a transmission side of the transfer shaft. SOLUTION: A transfer 22 is integrated with a transmission 2 with a transfer function part independent therefrom. An oil seal part 44 to shield the transmission 2 side and the transfer 22 side, and a bearing 46 to pivotably support the transfer shaft 42 are provided on an outer circumferential part of the end part on the transmission 2 side of the transfer shaft 42, and a spline fitting part 48 to spline-fit the transfer shaft 42 to a transmission output shaft 8 is provided on an inner circumferential part of the end part on the transmission 2 side of the transfer shaft 42.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transfer for a four-wheel drive vehicle, and more particularly to a transfer function portion of a transfer which is formed independently of a transmission, and a transmission portion is commonly used for two-wheel drive and four-wheel drive. The transmission output shaft does not need to be long, and the accuracy can be easily maintained, and the cost can be reduced.
The transfer of a four-wheel drive vehicle that is economically advantageous and can satisfy requirements such as lubrication performance by separating the transmission side from the transmission side by separating the transfer function part of the transfer from the transmission by the oil seal part. About.

[0002]

2. Description of the Related Art In a motor vehicle, a transmission ("T / T
M ”) and an automatic transmission.

The transmission is composed of a plurality of transmission gear trains such as an input gear train, a first gear train to a fifth gear train, a reverse gear train, and the like.
The driving force of the internal combustion engine input via the input shaft is shifted to a predetermined state. Then, the wheels are driven via the output shaft by the shifted driving force.

In some transmissions, a transfer (also referred to as "T / F") for distributing driving force to both front and rear wheels of an automobile is provided. Some transfer systems realize a part-time four-wheel drive vehicle or a full-time four-wheel drive vehicle.

[0005] As the transfer of the four-wheel drive vehicle,
There is one disclosed in JP-A-5-65945.
The transmission with an auxiliary transmission disclosed in this publication is provided with a final reduction gear pair between the vicinity of the rear end of the countershaft and the front end of the output shaft, and a transmission gear pair between the input shaft and the countershaft. Is established,
The front end of the low-speed gear shaft is spline-fitted coaxially to the short shaft portion provided at the rear end of the countershaft, and the low-speed gear shaft is connected to the low-speed driven gear coupled to the low-speed clutch teeth of the high-low speed switching mechanism. A low-speed transmission gear with an auxiliary transmission is formed by integrally forming a low-speed driving gear that meshes with the auxiliary transmission.

[0006] There is also one disclosed in Japanese Patent Application Laid-Open No. 9-269067. The transmission interlock device disclosed in this publication includes a first-speed / second-speed shifting rod for shifting to a first-speed state or a second-speed state, and a three-speed shifting rod.
A third-speed / fourth-speed shifting rod for shifting to a high-speed state or a fourth-speed state and a fifth-speed / reverse shifting rod for shifting to a fifth-speed state or a reverse state are arranged in parallel with each other, and A 5-speed shifting rod having the same rotation center as the 2-speed shifting rod and being slidable in the axial direction is provided, and two-wheel drive and 4-wheel drive shift are performed in parallel with the 5-speed shifting rod. In a transmission in which a shifting rod and a high-low shifting rod for four-wheel drive are disposed so as to be slidable in the axial direction, a five-speed shifting rod is provided between the five-speed shifting rod and the high-low shifting rod for four-wheel drive. A shift interlock pin, which has a five-speed shift interlock pin, and has a high / low shifting mechanism for the four-wheel drive. During de of low range prevents the upshift to fifth speed condition of the fifth speed shifting rod 5
When the high / low shifting rod during four-wheel drive is located in the low range, the five-speed interlock means provides the five-speed shifting rod.
The shift-up to the high-speed state is prevented, and a sudden decrease in driving force due to the shift-up and an engine stall due to a sudden decrease in speed are prevented.

[0007]

Conventionally, for example, in a four-wheel drive vehicle of the rear wheel drive (FR) type, FIG.
As shown in the figure, a transmission input shaft 104, a counter shaft 106, and a transmission output shaft 108 are supported in a transmission case 110 of the transmission 102.

The transmission input shaft 104 and the transmission output shaft 108 are connected so as to have the same center of rotation, and a counter shaft 106 is provided in parallel with the transmission input shaft 104 and the transmission output shaft 108. ing. A plurality of speed change gear trains 112 are provided between these shafts 104 to 108. The plurality of speed change gear trains 112 include, for example, an input gear train (not shown) and first to fourth gear trains 114 to 120.
And a reverse gear train (not shown).

At this time, the transmission 102
In FIG. 3, as shown in FIG. 3, a mechanism element for extending the length of the transmission output shaft 108 itself and distributing a driving force to a front wheel (not shown) is provided in the extended portion.

That is, as shown in FIG. 3, a transfer 122 is connected to the transmission 102 and provided.
The first chain sprocket 126 of the two-wheel drive / four-wheel drive switching mechanism 124 is provided in the middle of the transmission output shaft 108, and the second chain sprocket 126 is provided on the side of the front output shaft 128 arranged in parallel with the transmission output shaft 108.
A chain sprocket 130 is provided, and a chain 132 is wound around the first and second chain sprockets 126 and 130.

The transmission case 110 of the transmission 102 includes a transmission front case 134 surrounding a connection point between the transmission input shaft 104 and the transmission output shaft 108, and a transmission center case 136 surrounding an intermediate portion of the transmission output shaft 108. And a transmission rear case 138 surrounding the output side of the transmission output shaft 108. The transmission rear case 138 is connected to the transfer case 140 of the transfer 122.

In the extension type in which the length of the transmission output shaft itself is extended, (1) the number of parts can be reduced. (2) The total length of the transmission and the transfer can be reduced. (3) The transmission and the transfer can be made integrally compact. There are advantages such as.

However, on the contrary to the above advantages, there are the following disadvantages. (1) The length of the transmission output shaft to be extended is too long, and it is difficult to obtain accuracy. (2) Due to the requirement of lubrication performance and the like, it is difficult to provide a separate structure when it is desired to separate the transmission-side oil chamber and the transfer-side oil chamber. (3) Since the transmission and the transfer have an integrated structure, the difference from the transmission for a normal two-wheel drive vehicle becomes large, so that the parts themselves cannot be shared or the parts or the assembly are manufactured in units. ,Assembling,
Diversification of each fixation of the test is required. In particular, when the transmission is an automatic transmission having a complicated structure and control, the disadvantage of the item (3) becomes large.

[0014]

SUMMARY OF THE INVENTION Accordingly, the present invention is directed to a transfer for a four-wheel drive vehicle which is connected to a transmission and transmits driving force from the transmission to front and rear wheels. An input shaft and a transmission output shaft are provided, and a transfer shaft of the transfer connected to the transmission output shaft is provided. A two-wheel drive / four-wheel drive switching mechanism is provided in the transfer shaft, and a transmission-side end of the transfer shaft is provided. An oil seal portion that shields the transmission side and the transfer side and a bearing that supports the transfer shaft are provided at an outer peripheral portion,
A spline fitting portion for spline fitting the transfer shaft and the transmission output shaft is provided at an inner peripheral portion of a transmission side end of the transfer shaft.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION
When assembling the transfer to the transmission, the transfer function part of the transfer is independent from the transmission, and the two-wheel drive and four-wheel drive
While increasing the possibility that the transmission part can be shared, the transmission output shaft does not need to be formed long, making it easy to maintain accuracy.In addition, the oil seal part makes the transfer function part of the transfer independent from the transmission, and the transmission side Separated from the transfer side to satisfy requirements such as lubrication performance.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings.

FIG. 1 shows an embodiment of the present invention. In FIG. 1, reference numeral 2 denotes a transmission.

As shown in FIG. 1, the transmission 2 supports a transmission input shaft (not shown), a counter shaft (not shown), and a transmission output shaft 8 in a transmission case 10.

The plurality of speed change gear trains and the 1st / 2nd speed and 3rd / 4th speed switching mechanisms provided in the transmission 2 have the same configuration as the conventional one, and will be described. Is omitted.

Further, a transfer shaft 42 of the transfer 22 communicating with the transmission output shaft 8 is provided.
A two-wheel drive / four-wheel drive switching mechanism 24 is provided on the way. The two-wheel drive / four-wheel drive switching mechanism 24 includes a first chain sprocket 26 provided on a transfer shaft 42.
And a second chain sprocket (not shown) provided on a front output shaft (not shown), and a chain 32 wound around the first chain sprocket 26 and the second chain sprocket.

That is, in the transmission output shaft 8, the transmission output shaft is not provided as an extension as in the prior art, and an appropriate spline fitting portion 48 for transmitting the driving force to the transfer shaft 42 or a serration described later is taken into consideration. Length.

The transfer 22 has a structure in which the transfer function portion is independent of the transmission 2 and is integrated therewith.

That is, an oil seal portion 44 for shielding the transmission 2 side and the transfer 22 side and a bearing 46 for supporting the transfer shaft 42 are provided on an outer peripheral portion of an end portion of the transfer shaft 42 on the transmission 2 side. A spline fitting portion 48 for spline fitting the transfer shaft 42 and the transmission output shaft 8 is provided at an inner peripheral portion of the transfer shaft 42 at the transmission 2 side end.

More specifically, the transmission case 10 of the transmission 2 includes a transmission front case (not shown) surrounding a connecting portion between the transmission input shaft and the transmission output shaft 8, and an intermediate portion of the transmission output shaft 8 (not shown). A transmission center case, a transmission rear case 38 surrounding the output side of the transmission output shaft 8, and an extension case 50 surrounding a spline fitting portion 48 between the transmission output shaft 8 and the transfer shaft 42. The transfer case 40 of the transfer 22 is connected to the extension case 50.

At this time, the transfer case 40 includes a transfer front case 40-1 located on the transmission 2 side and the transfer front case 4
0-1 connected to a transfer case 40-2.

The oil seal portion 44 is mounted on an extension case 50 of the transmission 2 to seal the transmission 2 side and form a transmission-side oil chamber 52.
-1 and a second oil seal 44-2 mounted on the transfer front case 40-1 of the transfer 22 to seal the transfer 22 side and form the transfer side oil chamber 54.

The first of the oil seal portions 44,
The second oil seals 44-1 and 44-2 are separated by a predetermined gap S, and the transfer shaft 42 is surrounded by the extension case 50 and the transfer front case 40-1 at the outer peripheral portion of the end on the transmission 2 side. The space portion 56 is provided so as to be connected.

Further, the space 56 is opened to the atmosphere.
That is, a communication hole (not shown) communicating with the outside air is provided in the extension case 50 and / or the transfer front case 40-1, and the space 56 is opened to the atmosphere by the communication hole.

As shown in FIG. 1, the transfer shaft 42 has only a transfer function part independent and is supported in the transfer case 40 by the bearing 46 which supports the input side and the bearing 58 which supports the output side. You.

The transfer shaft 42 and the transmission output shaft 8 are connected by a spline fitting portion 48. A cylinder 60 is provided at an end of the transfer shaft 42 on the transmission 2 side.

The outer peripheral portion of the cylindrical portion 60 is formed with the same diameter and the same accuracy, and the sliding surfaces for the first and second oil seals 44-1 and 44-2 and the sliding surface are formed from the end on the transmission 2 side. The bearing 46 functions as an inner race support portion.

A second fitting portion on the transfer shaft 42 side is fitted to an inner peripheral portion of the cylindrical portion 60 so as to be fitted to the first fitting portion 48-1 of the transmission output shaft 8 of the spline fitting portion 48. 48-2 are formed.

Further, a transfer shaft 42 for assembling the transfer 22 to the transmission 2
As a measure for preventing the oil seal lip from being damaged at the end of the transmission 2, as shown in FIG. 1, the end face of the transmission output shaft 8 on the transfer 22 side is actually at least a distance L or more than the end face of the first oil seal 44-1. Is a layout that secures 10 mm or more.

Reference numeral 62 denotes a large-diameter portion formed on the transfer shaft 42. A cylindrical portion 60 is mounted on one end of the large-diameter portion 62 to bring the bearing 46 into contact with the large-diameter portion. Contacts the first chain sprocket 26 of the two-wheel drive / four-wheel drive switching mechanism 24,
It functions for positioning when the transfer shaft 42 is assembled.

Next, the operation will be described.

When the transfer 22 is assembled to the transmission 2, the transmission case 10 and the transfer case 40 of the transmission 2 are integrally connected. Compared with the conventional structure, the transmission case 10 is provided with the extension case 50 and the transfer case 40 is provided with the transfer front case 40-1. As a result, the transmission 2 and the transfer 22 are assembled. The extension case 50 and the transfer front case 40-1 are interposed at the parts.

At this time, the transmission output shaft 8 and the transfer shaft 42 are spline-fitted by the spline fitting portion 48.

As shown in FIG. 1, a first oil seal 44-1 and a second oil seal 4-1, which are located on the outer peripheral portion of the cylindrical portion 60 provided at the end of the transfer shaft 42 on the transmission 2 side, are arranged from the end of the transmission 2 side. 44-2 and the bearing 46 are sequentially arranged.

The first oil seal 44-1 is mounted on the extension case 50, seals the transmission 2 side, and seals the transmission side oil chamber 52.
And the second oil seal 44-2.
Is mounted on the transfer front case 40-1,
A transfer side oil chamber 54 is formed by sealing the transfer 22 side.

Further, the bearing 46 is supported by the transfer front case 40-1 and the large-diameter portion 62 when the transmission output shaft 8 and the transfer shaft 42 are spline-fitted.

Then, the first and second oil seals 44-1 and 44-2 of the oil seal portion 44 are separated by a predetermined gap S to make the transfer function portion of the transfer 22 independent from the transmission 2, Transmission side oil chamber 52 and transfer side oil chamber 5
A space 56 that is open to the atmosphere is formed between the four.

As a result, the transfer function portion of the transfer 22 from the transmission 2 can be formed independently, and the possibility of sharing the transmission 2 portion between the two-wheel drive and the four-wheel drive increases. It is practically advantageous. In particular, in an automatic transmission, the effect is increased.

Further, since it is not necessary to form the transmission output shaft 8 long, the precision can be easily maintained, the cost can be reduced, and it is economically advantageous.

Further, the transfer function portion of the transfer 22 is made independent from the transmission 2 by the oil seal portion 44, and the transmission-side oil chamber 52 and the transfer-side oil chamber 54 are separated, thereby satisfying requirements such as lubrication performance. obtain.

Further, the transmission output shaft 8 and the transfer shaft 42 are spline-fitted by the spline fitting portion 48, thereby simplifying the work at the time of assembling and improving the assembling workability. At the same time, the extra portion of the transmission output shaft 8 can function as a peep portion.

The oil seal portion 44 is attached to an extension case 50 of the transmission 2 to seal the transmission 2 side and form a first oil seal 44-1 for forming a transmission side oil chamber 52.
And a second oil seal 44-2 mounted on the transfer front case 40-1 of the transfer 22 to seal the transfer 22 side and form a transfer-side oil chamber 54. , The second oil seals 44-1 and 44-2 are separated by a predetermined gap S, and the extension case 50 and the transfer front case 40-
1 and the transmission 2 and the transfer 22
, The transmission side oil chamber 5
2 and the transfer-side oil chamber 54 can be easily divided, and the space 5
6 can be opened to the atmosphere, the optimal oil amount and oil type can be set, and cost reduction can be achieved.
In addition, it can contribute to improvement of performance.

It should be noted that the present invention is not limited to the above-described embodiment, and various application modifications are possible.

For example, in the embodiment of the present invention, an oil seal portion for shielding the transmission side and the transfer side and a bearing for supporting the transfer shaft are provided on the outer peripheral portion of the transmission side end of the transfer shaft. Although both the first and second oil seals forming the oil seal portion are located at the outer peripheral portion of the transmission side end of the transfer shaft, the first oil seal on the transmission side is installed on the transmission output shaft. It is also possible.

When the first oil seal on the transmission side is installed on the transmission output shaft, grease must be applied to the joint between the transmission and the transfer in a non-lubricated state in order to maintain the transfer attaching / detaching performance by preventing fretting. It is necessary to enclose a lubricant such as in advance.

Then, there is no fear of damaging the oil seal lip at the tip of the transmission output shaft when the transfer is assembled, and the usability can be improved.

In the embodiment of the present invention, the first and second oil seals 44-
To protrude the extension case 50 toward the transfer front case 40-1 at the outer peripheral portion of the extension case 50 in order to separate the extension case 50 and the extension case 50 by a predetermined gap S, as shown in FIG. Annular interposed member 7 between transfer front cases 40-1
2 and a predetermined gap S
(SG1) can be configured.

In this case, by using the annular interposition member 72, the joint surface portion between the extension case 50 and the transfer front case 40-1 can be formed substantially flush, which facilitates the manufacture. An arbitrary predetermined gap S can be secured by the thickness of the annular interposition member 72, which is practically advantageous.

Further, according to the embodiment of the present invention, when the transmission output shaft and the transfer shaft are spline-fitted, a cylindrical portion of the transfer shaft is formed, and a female mold is formed on the inner peripheral portion of the cylindrical portion. (2) Although a fitting portion is formed and the first fitting portion of the transmission output shaft is fitted, a female fitting portion is formed on the transmission output shaft side to reverse the fitting state (SG2). It is also possible to use

[0054]

As described above in detail, according to the present invention, in a transfer of a four-wheel drive vehicle connected to a transmission and transmitting a driving force from the transmission to front and rear wheels, a transmission input shaft and a transmission output shaft are provided to the transmission. And a transfer shaft for the transfer which communicates with the transmission output shaft, a two-wheel drive / four-wheel drive switching mechanism is provided in the middle of the transfer shaft, and the transmission side and the transfer side are provided at the outer peripheral portion of the transmission side end of the transfer shaft. An oil seal part that shields the transfer shaft and a bearing that supports the transfer shaft are provided, and the inner peripheral portion of the transmission side end of the transfer shaft is Since the spline fitting portion for spline fitting the transfer shaft and the transmission output shaft is provided, the transfer function portion of the transfer from the transmission can be formed independently, so that the two-wheel drive and the four-wheel drive can be used. The possibility that the transmission portion can be shared is increased, which is practically advantageous. In addition, since it is not necessary to form the transmission output shaft long, accuracy can be easily maintained, the cost can be reduced, and it is economically advantageous. Further, the transfer function portion of the transfer is made independent from the transmission by the oil seal portion, and the transmission side and the transfer side are separated, so that requirements such as lubrication performance can be satisfied. Furthermore, by spline-fitting the transmission output shaft and the transfer shaft with a spline fitting portion,
The work at the time of assembly can be simplified, the workability of assembly can be improved, and the extra portion of the transmission output shaft can also function as a peep portion.

[Brief description of the drawings]

FIG. 1 is an enlarged sectional view of a main part of a transfer of a four-wheel drive vehicle showing an embodiment of the present invention.

FIG. 2 is an enlarged sectional view of a main part of a transfer of a four-wheel drive vehicle showing another embodiment of the present invention.

FIG. 3 is a schematic configuration diagram of a transmission and a transfer of a four-wheel drive vehicle showing the prior art of the present invention.

[Explanation of symbols]

 2 Transmission 8 Transmission output shaft 10 Transmission case 22 Transfer 24 Two-wheel drive / Four-wheel drive switching mechanism 26 First chain sprocket 32 Chain 38 Transmission rear case 40 Transfer case 40-1 Transfer front case 40-2 Transfer rear case 42 Transfer shaft 44 Oil seal part 44-1 First oil seal 44-2 Second oil seal 46 Bearing 48 Spline fitting part 48-1 First fitting part 48-2 Second fitting part 50 Extension case 52 Transmission side oil chamber 54 Transfer-side oil chamber 56 Space 58 Bearing 60 Tube 62 Large diameter S Predetermined gap L Distance

Claims (3)

[Claims] 1. A transfer for a four-wheel drive vehicle connected to a transmission and transmitting driving force from the transmission to front and rear wheels, wherein the transmission is provided with a transmission input shaft and a transmission output shaft, and is connected to the transmission output shaft. An oil seal portion for providing a transfer shaft of the transfer, providing a two-wheel drive / four-wheel drive switching mechanism in the middle of the transfer shaft, and shielding the transmission side and the transfer side at an outer peripheral portion of a transmission side end of the transfer shaft. And a bearing for supporting the transfer shaft. A transfer shaft is provided at an inner peripheral portion of a transmission side end of the transfer shaft. A transfer for a four-wheel drive vehicle, characterized in that a spline fitting portion for spline fitting the shaft and the transmission output shaft is provided. A first oil seal mounted on an extension case of the transmission to seal a transmission side and form a transmission-side oil chamber; and an oil seal portion mounted on a transfer front case of the transfer and mounted on a transfer side case of the transfer. And a second oil seal forming a transfer-side oil chamber. The first case and the second oil seal are separated from each other by a predetermined gap, and the extension case and the transfer case are formed at an outer peripheral portion of a transmission-side end of the transfer shaft. The transfer of a four-wheel drive vehicle according to claim 1, wherein a space surrounded by the front case is connected to the space, and the space is opened to the atmosphere. 3. The device according to claim 2, wherein the predetermined gap between the first and second oil seals is adjusted by an annular interposition member interposed between the extension case and the transfer front case. Transfer of four-wheel drive vehicle.