JPH08164762A - Transfer unit - Google Patents

Abstract

PURPOSE: To secure such a device as being simple in structure, inexpensive in cost and excellent in operability by mounting each clutch sleeve of a clutch doing a transfer between 2WD and 4WD and another clutch doing a high-low transmission ratio transfer on a single shift rail. CONSTITUTION: A first shift fork 88 of a first clutch doing a transfer between 2WD and 4WD and a second shift fork 90 of a second clutch doing a high-low transmission ratio transfer both are mounted on a shift rail 86, respectively. The second shift fork 90 is fixedly installed in the shift rail 86 in regard to the axial direction, while the first shift fork 88 is elastically energized by a spring 94, whose one end is contacted by a snap ring 92, and mounted on the shift rail 86. Since both first and second clutch units 72 and 82 are controlled by the single shift rail 86 and thereby a required state is realizable, the structure is simplified and simultaneously manufacturing cost is reducible too.

Description

Detailed Description of the Invention

[0001]

The present invention relates to a two-wheel drive (hereinafter referred to as 2WD depending on the case) and a four-wheel drive (4W depending on the case below).
D) and a transfer device in a four-wheel drive vehicle that can be switched at any time.

[0002]

2. Description of the Related Art In a four-wheel drive vehicle capable of switching between two-wheel drive and four-wheel drive at any time, power is supplied to only one of the front and rear wheels that is always driven, for example, the rear wheel, or the front and rear wheels. A transfer device for supplying power to both wheels is usually provided with a clutch device for switching between 2WD and 4WD and a clutch device for switching between high and low speeds for switching a gear ratio.

Main parts of a conventional transfer device having the above-mentioned 2WD-4WD switching clutch device and high / low switching clutch device will be described with reference to the perspective view of FIG. 5 and the sectional view of FIG. First, in FIG. 5, reference numeral 10 is 2
A first clutch device for WD-4WD switching is generally shown, 12 is a first clutch sleeve for operating the clutch device 10, and 14 is a groove 16 provided in an outer peripheral surface of the first clutch sleeve 12. Has one end slidably fitted to the first shift rail 18 and the other end fixed to the first shift rail 18.
This is Shift Forbes. 20 is either one of the front and rear wheels,
For example, a general illustration of a second clutch device interposed between a high speed gear 22 and a low speed gear 24 mounted on an output shaft that supplies driving force to rear wheels that are constantly driven during traveling, 26 is a second for operating the clutch device 20
Clutch sleeve 28 is the second clutch sleeve 2
6 is a second shift fork, one end of which is slidably fitted in the groove 30 provided on the outer peripheral surface of 6, and the other end of which is fixed to the second shift rail 32. Second clutch sleeve 2
6 is a hub (not shown) fixed to the one output shaft
Is slidably attached to the outer periphery of the shaft in the axial direction and is integrally spline-coupled in the rotational direction around the axis, and moves to the left from the middle position shown in FIG. The high speed gear 22 is fixed to the output shaft by engaging with the spline 34, and is also moved rightward from the neutral position shown in FIG. 5 to engage with the low speed side clutch teeth or the spline 36. The low speed gear 24 is fixed to the output shaft.

As best shown in the cross-sectional view of FIG.
The first shift rail 18 and the second shift rail 32.
Are mounted on the transfer housing 38 so as to be slidable in the axial direction and close to each other and substantially parallel to each other, and are provided with concave grooves 42 and 44 with which one end operation end 40 ′ of the shift lever 40 is engaged. ing. As is well known in the art, the shift lever 40 is spherically supported by the transfer housing 38 at an intermediate portion in the longitudinal direction thereof, and has a grip (not shown) attached to a free end protruding outside the transfer housing. The operating end 40 'can be selectively engaged with the groove 42 or 44 by gripping and rotating in a direction perpendicular to the axis of the shift rail, which in turn rotates in the axial direction of the shift rail. The first shift rail 18 or the second shift rail 3 by
2 is displaced in the axial direction, and the first clutch sleeve 12 or the second clutch sleeve 26 is displaced in the axial direction via the first shift fork 14 or the second shift fork 26, respectively, to operate each clutch device 10, 20. You can In addition, the first shift rail 18 has 2WD and 4
Two recesses 42a and 42b for setting the rail position corresponding to WD, and the recess 42 by the spring 44.
There is provided a positioning device or a moderating device including a ball 46 press-fitted in a or 42b, and similarly, the second shift rail 32 has a recess 48a corresponding to a high position where the high speed gear 22 is fixed to the output shaft. , The recess 48b corresponding to the neutral position and the recess 48c corresponding to the low position where the low speed gear 24 is fixed to the output shaft, and the spring 50.
Therefore, a positioning device or a moderating device including a ball 52 press-fitted into the recess 48a, 48b or 48c is provided.

In the above conventional transfer device, 2WD
-4WD requires the first shift rail 18 for operating the first clutch device 10 for switching and the second shift rail 32 for operating the high / low second clutch device 20 for switching the gear ratio, and therefore the structure is complicated. However, it is inconvenient to operate because the shift lever 40 must be operated in two directions, a direction perpendicular to the shift rail axis and an axial direction. Since it is operated in two directions,
There are problems such as severe restrictions on the layout space to avoid interference with the transmission operation lever and the parking brake lever for operating the parking brake.

[0006]

SUMMARY OF THE INVENTION The present invention was devised in view of the above circumstances and has a simple structure and a low manufacturing cost as compared with a conventional transfer device of the same kind. 2WD-4WD
It is an object of the present invention to provide a transfer device in which the switching operation of the switch and the changeover of the high / low speed change ratio are simple and the operability is good, and the shift lever is arranged easily in terms of space.

[0007]

In order to achieve the above object, the present invention provides a first output shaft which is housed in a transfer housing and whose ends are drivingly connected to one of front and rear wheels, and the first output shaft. A first shaft clutch gear fixed to the other end of the shaft and a second output which is coaxially housed in the transfer housing with respect to the first output shaft and whose one end is drivingly connected to the other of the front and rear wheels. A shaft, a second shaft clutch gear fixedly mounted on the second output shaft, and a first clutch sleeve that integrally couples or separates the first shaft clutch gear and the second shaft clutch gear. A high speed gear and a low speed gear that are rotatably mounted on the second output shaft and are selectively fixed to the second output shaft by a second clutch sleeve; Sliding in parallel and in the axial direction A single shift seal disposed in the transfer housing, a shift lever pivotally supported by the transfer housing, one end of which is connected to the shift rail, and the rotation of which shifts the shift rail in the axial direction. A first and a second shift fork that are respectively mounted on the shift rails and that drive the first and second clutch sleeves to the engagement or disengagement positions by axial displacement of the shift rails, respectively. The transfer device is proposed.

In the present invention, the second shift fork that drives the second clutch sleeve is fixedly mounted on the shift rail, and the first shift fork that drives the first clutch sleeve is a spring in the axial direction. Preferably, the shift rail is mounted so as to be displaceable in the axial direction while receiving a biasing force. Further, the first clutch sleeve disengages the first shaft clutch gear and the second shaft clutch from the shift rail. A second axial position where the second clutch sleeve connects the high speed gear to the second output shaft, and the first clutch sleeve integrally connects the first shaft clutch gear and the second shaft clutch gear, and A second axial position in which the second clutch sleeve connects the high speed gear to the second output shaft, and the first clutch sleeve is the first shaft. A positioning device is provided for integrally connecting the latch gear and the second shaft clutch gear, and for positioning the second clutch sleeve at any of a third axial position where the low speed gear is connected to the second output shaft. It is preferable.

[0009]

With the above structure, the first clutch sleeve of the first clutch device for switching between 2WD and 4WD and the second clutch sleeve of the second clutch device for switching between the high and low transmission ratios are mounted on a single shift rail. Therefore, the structure is remarkably simple. Further, since the first clutch sleeve and the second clutch sleeve can be operated by the linear displacement of the shift rail, the operability of the shift lever is good, and the space arrangement of the shift lever is easy.

[0010]

Embodiments of the present invention will be specifically described below with reference to FIGS. First, FIG. 2 is a conceptual configuration diagram of a four-wheel drive vehicle equipped with a transfer device according to the present invention. Reference numerals a ₁ and a ₂ are left and right front wheels, and b ₁ and b ₂ are left and right front wheels a ₁ and Left and right front axles for driving a ₂ , c is a known front differential interposed between the left and right front axles, d ₁ and d ₂ are rear wheels, and e ₁ and e ₂ are left and right rear wheels Left and right rear axles driving d ₁ and d ₂ , f is a rear differential known per se interposed between the left and right rear axles, g is an engine, h is a transmission connected to the output end of the engine g, j Is the same transmission h
, A transfer device connected to the output end of k, k ₁ is a front wheel propeller shaft connecting the transfer device j and the front differential c, k ₂ is a transfer device j
The rear wheel propeller shaft connects the rear differential gear f with the rear differential. It should be noted that either _{one of the} front shafts b ₁ and b ₂ , in the illustrated case, the left front shaft b ₁ is driven by two wheels during traveling and is driven by a high gear ratio (hereinafter abbreviated as 2H) to be driven by four wheels. In order to smoothly switch the high gear ratio (hereinafter abbreviated as 4H), for example, the published utility model publication 3-
A freewheel clutch device m as disclosed in No. 33723 is interposed.

The overall structure of the transfer device j is shown in FIG.
1 and the detailed structure of the essential part thereof is shown in the sectional view of FIG. First, in FIG. 3, reference numeral 54 is a transfer input gear fixed to the output shaft of the transmission h, 56 is a counter large gear meshing with the transfer input gear 54, and 58 is a counter large gear integrated with the counter large gear on the counter shaft 60. It is a counter small gear rotatably supported. First output shafts 62 and 64 are arranged in parallel and substantially coaxially with the counter shaft 60, and the first output shaft 62 is one of the propeller shafts of the front and rear wheels, for example, the front wheel propeller shaft k _1. Or formed integrally with the propeller shaft k ₁ . The second output shaft 64 is connected to the other propeller shaft of the front and rear wheels, for example, the rear wheel propeller shaft k ₂ or is formed integrally with the propeller shaft k ₂ .

At the other end of the first output shaft 62 opposite to the front wheel propeller shaft connecting end, the first shaft clutch gear 6 is provided.
6 is fixed, a second shaft clutch gear 68 is fixed to the adjacent end of the second output shaft 64, and the first shaft clutch gear 66 and the second shaft clutch gear 68 are the first shaft clutch gear 66 and the second shaft clutch gear 68.
A first clutch device 72 for switching between 2WD and 4WD is formed together with the clutch sleeve 70. In FIG.
Since the first clutch sleeve engages the first shaft clutch gear 66 and does not engage the second shaft clutch gear 66,
The output shaft 62 and the second output shaft 64 are separated from each other. Therefore, as will be described later, the driving force is transmitted only to the second output shaft 64, which is in the 2WD state. From this state, the first clutch sleeve 70 moves to the right to move the first shaft clutch gear 66 and the second clutch gear 70.
When engaged with both of the axial clutch gears 68, the first and second
The output shafts 62 and 64 are integrally connected to be in the 4WD state.

Further, the second output shaft 64 is rotatably mounted with a high speed 74 which is always meshed with the counter large gear 56 and a low speed gear 76 which is always meshed with the counter small gear 58. A clutch hub 78 is integrally formed with the second output shaft 64 between the two gears 74 and 76 or is formed separately from the second output shaft 64 and is mounted on the same output shaft so as not to rotate relative to each other. The high speed gear 74 is provided with clutch teeth or splines 74 ', and the low speed gear 76 is provided with clutch teeth or splines 76'.
And 76 'cooperate with a second clutch sleeve 80, with clutch teeth or splines 78' provided on the outer circumference of the clutch hub 78. The clutch teeth or splines 74 'of the high speed gear and the low speed gear 76
Clutch teeth or splines 76 'and clutch hub 7
8 and the second clutch sleeve 80 form a second clutch device 82 for switching the high / low speed ratio.

In FIG. 3, the second clutch sleeve 8
0 engages with the clutch teeth or splines 74 ′ of the high speed gear 74 and the clutch teeth or splines 78 ′ of the clutch hub 78, so that the high speed gear 74 is fixed to the second output shaft 64 at 2H (second position). 1 clutch device 7
When 2 is engaged, the state is 4H). When the second clutch sleeve 80 moves to the right from the illustrated position and engages with the clutch teeth or the splines 76 ′ of the low speed gear 76, the low speed gear 76 is fixed to the second output shaft 64. Therefore, if the first clutch device 72 is engaged,
A low gear ratio of four-wheel drive, a so-called 4L state is set.

As best shown in the detailed cross-sectional view of FIG. 1, a single shift rail 86 is axially slidable in a transfer housing 84, and a first output shaft 62 and a second output shaft 64 are provided. Are arranged substantially parallel to. On the shift rail 86, a first end is slidably fitted in a groove provided on the outer periphery of the first clutch sleeve 70.
The shift fork 88 and the second shift fork 90, one end of which is slidably fitted in a groove provided on the outer circumference of the second clutch sleeve 80, are mounted. The second shift fork 90 includes the shift rail 8 in the axial direction.
6, the first shift fork 88 is elastically urged to the left in the drawing by a spring 94 having one end abutted against the snap ring 92, and the first shift fork 88 is shifted.
It is mounted on top. Therefore, the first shift fork 88
Is provided on the shift rail 86 by compression of the spring 94 so as to be displaced in a required amount in the axial direction. With this structure, the first clutch sleeve 70 is engaged with the first shaft clutch gear 66. From the 2H state, there is an advantage that the clutch sleeve 70 is moved to the right while traveling to engage with the second shaft clutch gear 68 to achieve smooth engagement when the 4H state is realized.

Further, on the transfer housing 84,
A shift lever 98 via a spherical support device 96 known per se
The shift lever 98 has one end 100 slidably fitted in an engaging groove or an engaging hole 102 of the shift rail 86, and the other end free end 104 of the shift lever is not shown. The omitted grip is installed.
In FIG. 1, the shift lever 98 is in the 4H state, at which time the first clutch sleeve 70 is engaged with the first shaft clutch gear 66 and the second shaft clutch gear 68,
The first output shaft 62 and the second output shaft 64 are integrally connected, and the front and rear wheels a ₁ , a ₂ , b ₁ , b ₂ are driven. Further, at this time, the second clutch sleeve 80 is engaged with the clutch teeth or splines 74 ′ of the high speed gear 74 and the clutch teeth or splines 78 ′ of the clutch hub 78, so that the high speed gear 74 is connected to the second output shaft 64. It is fixed to. Further, the ball 108 urged by the spring 106 engages with the positioning recess 110 provided in the shift rail 86 to correctly position the shift rail 86 at the 4H position.

Next, when the shift lever 98 is rotated to the 2H position in the clockwise direction (rearward direction) as shown by the alternate long and short dash line in FIG. 1, the shift rail 86 moves to the left and the first clutch sleeve 70. Moves to the left, and the engagement between the clutch sleeve 70 and the second shaft clutch tooth 68 is released. Meanwhile, the second
The clutch sleeve 80 still engages the clutch teeth or splines 74 'of the high speed gear 74, so
The H state is achieved. At this time, the ball 108 engages with the recess 112 of the shift rail 86 to correctly position the shift rail 86 at the 2H position. Further, when the shift lever 98 is rotated to the counterclockwise (forward) 4L position as shown by the chain double-dashed line in FIG.
6 moves to the right, and the first clutch sleeve 70 and the second clutch sleeve 80 move to the right. First clutch sleeve 70
Keeps the 4WD state by engaging both the first shaft clutch gear 66 and the second shaft clutch gear 68 even when moved to the right,
The second clutch sleeve 80 disengages from the clutch teeth or splines 74 'of the high speed gear 74 and engages with the clutch teeth or splines 76' of the low speed gear 76 to achieve the 4L state. At this time, the ball 108 engages with the recess 114 of the shift rail 86 to correctly position the shift rail 86 at the 4L position. Switching from the 2H state to the 4H state during normal traveling is performed smoothly during traveling in cooperation with the freewheel clutch device m, and the gear ratio is significantly different when switching from the 4H state to the 4L state. , It will be held after stopping. In addition, in FIG.
The operation modes of the first and second sleeves 70 and 80 of the first and second clutch devices 72 and 82 in the H, 4H, and 4L states are displayed in an easy-to-understand manner. As shown in the drawing, the clutch teeth or splines of the first and second sleeves 70 and 80 are long straight teeth so that engagement and disengagement can be smoothly performed.

In FIG. 1, reference numeral 116 is a switch for activating a display device such as a lamp for indicating that the 2H state has changed to the 4H state, or vice versa. Oil seal, 1
18 is a cover, 120 is a dustproof boot, 122 is a ball bearing, and 124 is a needle bearing.

According to the above configuration, the single shift rail 8
Since the first and second clutch devices 72 and 82 can be controlled by 6 to realize the required 2H, 4H and 4L states, the structure is remarkably simplified and the manufacturing cost is reduced as compared with the conventional similar transfer device. be able to.
Further, since the operation of the shift lever 98 is performed linearly within one plane including the axis of the shift rail 86, the operation is easy, and the space constraint concerning the arrangement of the shift lever 98 is small, and the transmission operation lever and There is an advantage that the degree of freedom in design is large in relation to the arrangement of the parking brake lever and the like.

[0020]

As described above, the transfer device according to the present invention includes the first output shaft housed in the transfer housing and one end of which is drivingly connected to one of the front and rear wheels.
A first shaft clutch gear fixed to the other end of the first output shaft, and a first housing which is housed coaxially with the first output shaft in the transfer housing and one end of which is drivingly connected to the other of the front and rear wheels. A second output shaft, a second shaft clutch gear fixedly mounted on the second output shaft, and a first shaft for integrally coupling or separating the first shaft clutch gear and the second shaft clutch gear. Clutch sleeve, a high speed gear and a low speed gear rotatably mounted on the second shaft and selectively fixed to the second shaft by the second clutch sleeve, and a high speed gear and A single shift rail that is disposed in the transfer housing in parallel and slidably in the axial direction, and one end that is pivotally supported by the transfer housing and that is connected at one end to the shift rail. A shift lever that displaces in direction,
A first and a second shift fork that are respectively mounted on the shift rails and that drive the first and second clutch sleeves to the engagement or disengagement positions by axial displacement of the shift rails. As compared with the conventional transfer device of the same kind, the structure is remarkably simple, the manufacturing cost is low, the operability is good, and the restrictions on the arrangement space are small.

[Brief description of drawings]

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

FIG. 2 is a schematic plan view of an entire vehicle including a transfer device according to the present invention.

FIG. 3 is a schematic mechanism diagram of the entire transfer device according to the present invention.

FIG. 4 is a development view illustrating an operation mode of first and second clutch devices in the transfer device according to the present invention.

FIG. 5 is a perspective view of a main part of a conventional transfer device.

6 is a cross-sectional view of an essential part of the transfer device shown in FIG.

[Explanation of symbols]

a ₁ , a ₂ ... front wheels; d ₁ , d ₂ ... rear wheels; g ... engine;
h ... transmission; j ... transfer device; k ₁
Front wheel propeller shaft; k ₂ Rear wheel propeller shaft; 54 ... Transfer input gears; 56 and 58 ... Counter gears; 62 ... First output shaft; 64 ... Second output shaft; 66
... 1st shaft clutch gear; 68 ... 2nd shaft clutch gear; 7
0 ... 1st clutch sleeve; 72 ... 1st clutch device;
74 ... High-speed gears; 76 ... Low-speed gears; 8
0 ... second clutch sleeve; 82 ... second clutch device;
84 ... Transfer housing; 86 ... Shift rail,
88 ... 1st shift fork; 90 ... 2nd shift fork; 98 ... shift lever.

Claims (3)

[Claims] 1. A first output shaft housed in a transfer housing, one end of which is drivingly connected to one of the front and rear wheels, and a first shaft clutch gear fixed to the other end of the first output shaft. A second output shaft which is coaxially housed in the transfer housing with respect to the first output shaft and whose one end is drivingly connected to the other of the front and rear wheels, and is fixedly mounted on the second output shaft. A second shaft clutch gear, a first clutch sleeve that integrally connects or separates the first shaft clutch gear and the second shaft clutch gear, and is rotatably mounted on the second output shaft. A high speed gear and a low speed gear, which are selectively fixed to the second output shaft by a second clutch sleeve, and are arranged in the transfer housing so as to be slidable substantially parallel to the first output shaft and axially. Single shift installed And a shift lever pivotally supported by the transfer housing, one end of which is coupled to the shift rail, and the rotation of which shift lever displaces the shift rail in the axial direction; A transfer device comprising: first and second shift forks that drive the first and second clutch sleeves to an engagement or disengagement position, respectively, by displacement. 2. A second shift fork that drives the second clutch sleeve is fixedly mounted on the shift seal, and a first shift fork that drives the first clutch sleeve is axially attached by a spring. The transfer device according to claim 1, wherein the transfer device is mounted so that it can be displaced in the axial direction while receiving a force. 3. The first rail connecting the shift rail to the second output shaft, wherein the first clutch sleeve separates the first shaft clutch gear from the second shaft clutch gear and the second clutch sleeve connects the high speed gear to the second output shaft. And the second clutch sleeve integrally connects the first clutch sleeve to the first shaft clutch gear and the second shaft clutch gear, and the second clutch sleeve connects the high speed gear to the second output shaft. The axial position of the first clutch sleeve is
A positioning device is provided for integrally connecting the shaft clutch gear and the second shaft clutch gear, and for positioning the second clutch sleeve at any of a third axial position where the low speed gear is connected to the second output shaft. The transfer device according to claim 1, wherein the transfer device is provided.