JPH07266907A - Gear train structure of auxiliary transmission - Google Patents

Abstract

PURPOSE:To reduce generation of noise and oscillation at the time of high speed driving by providing a two-wheel and four-wheel changeover mechanism between a driven sprocket for high speed and a driven gear for low speed and a transmission means for high speed to communicate the driven sprocket for high speed and a drive sprocket for high speed to each other. CONSTITUTION:A low speed and high speed changeover sleeve 62 is engaged with an input side hub spline 54 and an input side high speed spline 60 by releasing it from an input side low speed spline 58 and a two-wheel and four-wheel changeover sleeve 80 is engaged only with an output side high speed spline 78 by releasing it from an output side low speed spline 76 and an output side hub spline 72 in the case of high speed two-wheel drive in an auxiliary transmission 8. Driving force from a transmission is transmitted only to a rear side propeller shaft through an input shaft 28, an input side hub 56, the low speed and high speed changeover sleeve 62, a drive sprocket 50 for high speed, a chain 92 for high speed, a driven sprocket 68 for high speed and a rear side output shaft 32.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gear train structure of an auxiliary transmission, and particularly to an auxiliary transmission capable of switching between a low speed and a high speed, noise and vibration during high speed two-wheel drive and high speed four-wheel drive. The present invention relates to a gear train structure of a transmission that can reduce the occurrence of noise.

[0002]

2. Description of the Related Art In a power transmission system of a vehicle, a transmission connected to an engine, an auxiliary transmission (transfer) connected to the transmission, a front differential and a rear differential connected to the auxiliary transmission. Some are equipped with a side differential.

Some auxiliary transmissions input a driving force from the transmission and transmit the driving force to a front differential gear and a rear differential gear so as to distribute the driving force to the front wheels and the rear wheels.

As this auxiliary transmission, for example, there is one having a structure shown in FIG. That is, as shown in FIG. 8, the auxiliary transmission 102 has an input shaft 104 for inputting a driving force from a transmission (not shown), a front output shaft 106 disposed substantially parallel to the input shaft 104, It has a rear output shaft 108 which is rotatable coaxially with respect to the front output shaft 106. An input gear 110 is fixedly provided on the input shaft 104. Further, the front output shaft 106 is provided with an output gear 112 corresponding to the input gear 110.
The input gear 110 and the output gear 112 include a counter shaft 114 between the input shaft 104 and the front and rear output shafts 106 and 108.
The counter gear 116 is rotatably mounted on the counter gear 116. Further, the counter shaft 114 has a rear output shaft 108 side and a low speed (low range) drive gear 1
18 is rotatably provided. A low speed driven gear 120 that can directly mesh with the low speed drive gear 118 is rotatably provided on the rear output shaft 108.
A low speed / high speed switching mechanism 124 is provided between the output gear 112 and the low speed driven gear 120 to connect / disconnect the front output shaft 106 and the rear output shaft 108 by a low speed / high speed switching sleeve 122. Further, the front output shaft 106
Between the rear output shaft 108 and the rear output shaft 108, a two-wheel / four-wheel switching sleeve 1
26 is the output gear 112 or the low speed driven gear 12
There is provided a two-wheel / four-wheel switching mechanism 128 which selectively engages with any one of 0 and connects the output gear 112 or the low speed driven gear 120 to the rear output shaft 108.

According to the auxiliary transmission 102 of FIG. 8, the front output shaft 106 and the rear output shaft 108 are separated by the two-wheel / four-wheel switching mechanism 128 during high-speed two-wheel drive, and low-speed / high-speed switching is performed. Output gear 112 by mechanism 124
By connecting the rear output shaft 108 to the rear output shaft 108, the driving force from the transmission is transmitted only through the input shaft 104, the input gear 110, the counter gear 116, the output gear 112, and the rear output shaft 108 to the rear differential gear. Be transmitted to. Further, during high-speed four-wheel drive, the two-wheel / four-wheel switching mechanism 128 connects the front output shaft 106 and the rear output shaft 108, and the low-speed / high-speed switching mechanism 124 connects the output gear 112 and the rear output shaft 108. The driving force from the transmission is connected to the input shaft 104, the input gear 110, and the counter gear 1.
16, the output gear 112, the front output shaft 106, and the rear output shaft 108. Furthermore, when driving at low speed with four wheels,
The two-wheel / four-wheel switching mechanism 128 connects the front output shaft 106 and the rear output shaft 108, and the low-speed / high-speed switching mechanism 124 connects the low-speed driven gear 120 and the rear output shaft 108, thereby changing the speed. The driving force from the machine is the input shaft 104, the input gear 110, the counter gear 116, the counter shaft 114, and the low speed drive gear 118.
Is transmitted to the low speed driven gear 120, the rear output shaft 108, and the front output shaft 106.

Further, as the structure of such an auxiliary transmission, for example, JP-A-63-130433, JP-A-59-80126, JP-A-59-190026 and JP-A-58-58 can be used. Japanese Patent No. 58934, Shokai 58-1
It is disclosed in Japanese Patent No. 16417 and Japanese Utility Model Laid-Open No. 58-100131. Japanese Patent Application Laid-Open No. 63-130433 discloses a second clutch gear integrally formed on a main drive shaft and a second clutch gear rotatably supported on the main drive shaft, the second clutch gear integrally formed on the main drive gear meshing with the counter gear. A first hub; a first clutch gear integrally formed with the main shaft; and a first switching means that meshes with the first hub, the first clutch gear and the second clutch gear,
A fourth unit integrally formed with a transmission gear that receives rotational power from the counter gear and is rotatably supported by the main shaft.
The clutch gear and the third integrally formed on the main shaft
A second hub that is integrally formed with a clutch gear, a sprocket gear that is connected to a front drive shaft via a chain, and is rotatably supported by a main shaft;
A hub, a third clutch gear, and a second switching means that meshes with the fourth clutch gear are provided, whereby the second and fourth gears are driven during each of 2H (high-speed two-wheel drive) or 4H (high-speed four-wheel drive). The clutch gear is not meshed with each coupling sleeve as the first and second switching means, the counter gear is not rotated, and therefore rattling noise due to idling of the counter gear is not generated, and the counter gear is unnecessary. This eliminates unnecessary rotation and controls the power loss of the drive system to the minimum. In Japanese Utility Model Laid-Open No. 59-80126, a pair of drive gears which are coupled to the input shaft so as to be selectively transmittable in rotation on the axis of the input shaft and the rotation of both drive gears are front. The output shaft and the rear output shaft are provided with a clutch device that can be selectively transmitted to the respective output shafts or both output shafts. JP-A-59-19002
No. 6 discloses a reduction mechanism for rotating the first output shaft and the second output shaft at a low speed when rotating the first output shaft and the second output shaft at a high speed. (2) By transmitting the rotation in the same direction as the rotation transmission direction when rotating the output shaft at a low speed, it is possible to prevent the deceleration mechanism unnecessary for power distribution from rotating at a high speed and reduce the noise source of the vehicle. In addition, the durability of the bearing of the reduction mechanism is improved. 58-58934
In the one described in the publication, a switch for opening and closing by driving the rod is provided on the low speed / high speed switching rod, and a drive means for switching between all wheels and rear wheels via the switch is provided. It is set so as to form a loop. Japanese Utility Model Application Laid-Open No. 58-116417 discloses an input shaft connected to an output shaft of a transmission, a first counter drive gear integrally provided on the input shaft, and a coaxial arrangement with the input shaft. First installed and assembled so that relative rotation is possible
An output shaft, a second counter drive gear rotatably mounted on the first output shaft, a first switching device that selectively connects the input shaft and the first output shaft, a first output shaft and a second counter A second switching device for selectively connecting a drive gear, a counter shaft integrally having a first counter gear that constantly meshes with the first or second counter drive gear, and a rotatably mounted on the counter shaft. A second counter gear that constantly meshes with the second or first counter drive gear, a third switching device that selectively connects the second counter gear and the counter shaft, and a counter gear that constantly meshes with the second counter drive gear. A second output shaft integrally provided with a meshing output gear. 58
The one disclosed in Japanese Unexamined Patent Publication No. 100131 corresponds to a slide shaft that is biased by a control lever and moves back and forth in the axial direction, an engagement groove provided at a required position on the outer peripheral surface of the tride shaft, and the engagement groove. A fork that is slidably fitted to the outer periphery of the slide shaft and that engages with a shift sleeve for switching between all-wheel drive and two-wheel drive, and a cavity that is provided inside the fork and has one end opening facing the engagement groove. And an engaging member that is fitted into the opening of the cavity so as to be able to be inserted and retracted, and an elastic member that is housed in the cavity and that aligns the engaging element in the protruding direction to elastically engage the engaging groove. , The engagement groove is a trough-shaped positioning portion for stably holding the engagement element and positioning the fork on the slide shaft, and the fork shifts even if the control lever is shifted from the all-wheel drive position to the two-wheel drive position. For this reason, when the slide shaft cannot be followed, the repulsive force is stored in the elastic member by pressing the engager in the retracted direction and the repulsive force of the elastic member is used to disengage the engager when the shift lock is released. And a guide slope portion for returning to the positioning portion.

[0007]

However, conventionally, in the sub-transmission, the low speed drive gear and the low speed driven gear have the following structures due to their structure at the time of high speed two-wheel drive (2H) or high speed four-wheel drive (4H). Although it is not necessary, since it is idling, there is a disadvantage that noise and vibration are increased.

Further, a large number of gear mechanisms are required, the structure of the gear mechanism is complicated, the degree of freedom in design is reduced, the size is increased, and the frequency of use of each gear is high. However, there is an inconvenience that it becomes expensive.

[0009]

Therefore, in order to eliminate the above-mentioned inconvenience, the present invention firstly provides an input shaft to which a driving force is input, and the input shaft is provided with a low speed drive gear and a high speed drive gear. A drive sprocket is rotatably provided, and a low speed / high speed switching mechanism is provided between the low speed drive gear and the high speed drive sprocket, and the front output shaft and the front output shaft are rotatable substantially parallel to the input shaft. A rear output shaft is provided, a low speed driven gear is rotatably provided on the front output shaft, and low speed transmission means for connecting the low speed driven gear and the low speed drive gear is provided, and the rear output shaft is provided. A high-speed driven sprocket is fixedly provided, and a two-wheel / four-wheel switching mechanism is provided between the high-speed driven sprocket and the low-speed driven gear. Characterized in that the provided high-speed transmission means to contact said high-speed drive sprocket and.

Secondly, the high-speed transmission means is a high-speed chain wound around the high-speed drive sprocket and the high-speed driven sprocket.

[0011]

According to the structure of the present invention, firstly, the low speed drive gear is rotatably provided on the input shaft and the low speed driven gear is rotatably provided on the output shaft. The generation of noise and vibration can be reduced without idling the low speed drive gear and the low speed driven gear during high speed four-wheel drive.

Second, since a high-speed chain is used in high-speed two-wheel drive and high-speed four-wheel drive, the structure of the gear mechanism is simplified, which increases the degree of freedom in design, and The auxiliary transmission can be made compact, the frequency of use of the gears is reduced, high-precision gears are not required, and cold forged gears can be used, so that the cost can be reduced.

[0013]

Embodiments of the present invention will be described in detail and specifically with reference to the drawings. 1 to 5 show an embodiment of the present invention. In FIG. 5, 2 is a vehicle, 4 is an engine, 6 is a transmission, 8 is an auxiliary transmission (transfer), 1
0 is a front differential gear, 12 is a rear differential gear, 14 and 14 are front wheel shafts, 16 and 16 are front wheels, 18 and 18 are rear wheel shafts,
20 and 20 are rear wheels, and 22 is a radiator.

A primary propeller shaft 22 is provided between the transmission 6 and the sub transmission 8. Further, the auxiliary transmission 8 includes a front propeller shaft 24 connected to the front differential gear 10,
A rear propeller shaft 26 connected to the rear differential 12 is connected.

The sub-transmission 8 inputs the driving force from the transmission 6, and the driving force is applied to the front wheels 16 and 16 and the rear wheels 20 and 2.
0 to the front differential gear 10 via the front propeller shaft 24, and to the rear differential gears 12 and 12 via the rear propeller shaft 26, and at a low speed (low range). ) And high speed (high range), and two and four wheels.

As shown in FIG. 1, the auxiliary transmission 8 has an input shaft 28, a front output shaft 30 substantially parallel to the input shaft 28, and a rear output shaft 32 rotatable with respect to the front output shaft 30.
And have. Both ends of the input shaft 28 are first and second
Rotatably supported by the input shaft bearings 34, 36,
Connect with propeller shaft 22. One end of the front output shaft 30 is rotatably supported by a front output shaft bearing 38,
The front propeller shaft 24 is connected to this one end side. The other end of the rear output shaft 32 is rotatably supported by the rear output shaft bearing 40, and the other end of the rear output shaft 32 is connected to the rear propeller shaft 26.

The other end of the front output shaft 30 and the rear output shaft 32
Is connected to one end side thereof by a connecting bearing 42 so as to be freely rotatable with respect to each other.

The first input shaft bearing 3 is provided on the input shaft 28.
A low speed drive gear 46 is rotatably provided on the fourth side by a first low speed side bearing 44, and a high speed drive sprocket 50 is freely rotatable on a second input shaft bearing 36 side by a first high speed side bearing 48. It is provided.

A low speed / high speed switching mechanism 52 is provided between the low speed drive gear 46 and the high speed drive sprocket 50.

The low speed / high speed switching mechanism 52 is provided with the input shaft 2
8, an input hub 56 having an input hub spline 54 formed on the periphery thereof, an input low speed spline 58 integrally formed with the low speed drive gear 46, and a high speed drive sprocket 50 integrally provided. The input side high speed spline 60, the input side hub spline 54, the input side low speed spline 58, and the low speed / high speed switching sleeve 62 that is axially moved to engage / disengage the input side high speed spline 60. There is.

A low speed driven gear 64 corresponding to the low speed drive gear 46 is rotatably provided on the front output shaft 30 by a second low speed side bearing 66.

A high-speed driven sprocket 68 is fixedly provided on the rear output shaft 32 in correspondence with the high-speed drive sprocket 50.

A two-wheel / four-wheel switching mechanism 70 is provided between the low speed driven gear 64 and the high speed driven sprocket 68.

The two-wheel / four-wheel switching mechanism 70 is integrated with the low-speed driven gear 64 and an output hub 74 fixed to the other end of the front output shaft 30 and having an output hub spline 72 formed on the periphery thereof. Output side low speed spline 7
6, an output-side high-speed spline 78 integrally provided on the high-speed driven sprocket 68, an output-side hub spline 72, an output-side low-speed spline 76, and an output-side high-speed spline 78 are axially moved to engage / disengage. And a two-wheel / four-wheel switching sleeve 80.

The low speed drive gear 46 and the low speed driven gear 64 are connected by a low speed transmission means 82.

The low-speed transmission means 82 is an intermediate shaft 84 disposed between the input shaft 28 and the front and rear output shafts 30 and 32 substantially in parallel with these shafts. An idler gear 88 is rotatably supported by the side bearing 86 and meshes with the low speed drive gear 46 and the low speed driven gear 64. Both ends of the intermediate shaft 84 are fixed to a case (not shown) of the auxiliary transmission 8.

Further, the high speed drive sprocket 50 and the high speed driven sprocket 68 are connected by a high speed transmission means 90. This high speed transmission means 90
It comprises a high speed drive sprocket 50 and a high speed chain 92 wound around a high speed driven sprocket 68.

Next, the operation of this embodiment will be described.

In the auxiliary transmission 8, a high speed two-wheel drive (2
In the case of H), as shown in FIG. 1, the low-speed / high-speed switching sleeve 62 is disengaged from the input-side low-speed spline 58 to input-side hub spline 54 and input-side high-speed spline 6
2 and 4 wheel switching sleeve 80
Is disengaged from the output side low speed spline 76 and the output side hub spline 72 and engaged only with the output side high speed spline 78. As a result, the driving force from the transmission 6 is transmitted to the input shaft 28, the input side hub 56, the low speed / high speed switching sleeve 6
2, high speed drive sprocket 50, high speed chain 92, high speed driven sprocket 68, and rear output shaft 3
2 and is transmitted only to the rear propeller shaft 26. Therefore, at this time, the low speed drive gear 46 and the low speed driven gear 64 do not idle.

When the auxiliary transmission 8 is a high speed four-wheel drive (4H), as shown in FIG. 2, the low speed / high speed switching sleeve 62 is disengaged from the input side low speed spline 58 and the input side hub spline 54 and the input side. While engaging with the high speed spline 60, the two-wheel / four-wheel switching sleeve 80 disengages from the output side low speed spline 76 and engages with the output side hub spline 72 and the output side high speed spline 78. As a result, the driving force from the transmission 6 is applied to the input shaft 28, the input hub 56, the low speed / high speed switching sleeve 62, the high speed drive sprocket 50, the high speed chain 92, the high speed driven sprocket 68, and the rear output shaft 32. Is transmitted to the rear propeller shaft 26 via the two-wheel / four-wheel switching sleeve 80, the output hub 74, and the front output shaft 30, and is transmitted to the front propeller shaft 24. Therefore, at this time, the low speed drive gear 46 and the high speed driven sprocket 64 do not idle.

When the auxiliary transmission 8 is in the neutral (N) state, as shown in FIG. 3, the low speed / high speed switching sleeve 62 is used.
Is separated from the input side low speed spline 58 and the input side high speed spline 60, and the input side hub spline 5
Only 4 is engaged. As a result, the driving force from the transmission 6 is transmitted to the input shaft 28, but the low speed / high speed switching sleeve 62 is not engaged with the input side low speed spline 58 and the input side high speed spline 60. It is not transmitted to 30 and the rear output shaft 32 side.

When the sub transmission 8 is a low speed four-wheel drive (4L), the low speed / high speed switching sleeve 62 is disengaged from the input side high speed spline 60 and engaged with the input side hub spline 54 and the input side low speed spline 58. In addition, the two-wheel / four-wheel switching sleeve 80 engages with the output hub spline 72, the output low speed spline 76, and the output high speed spline 78. As a result, the driving force of the transmission 6 is
8, the input side hub 56, the low speed / high speed switching sleeve 62, the low speed drive gear 46, the idler gear 88, the low speed driven gear 64, the front output shaft 30 and the front propeller shaft 24, and the output hubs 74 and 2 It is transmitted to the rear propeller shaft 26 via the four-wheel / four-wheel switching sleeve 80, the high-speed driven sprocket 68, and the rear output shaft 32.

As a result, the low-speed drive gear 46 and the low-speed driven gear 64, which are unnecessary gears at the time of high-speed two-wheel drive (2H) and high-speed four-wheel drive (4H), are not idled, so that noise and vibration are not generated. Can be reduced.

Further, since the high-speed chain 92 is used as the high-speed transmission means 90, it is not necessary to install an intermediate gear on the high-speed side, the structure is simple, the degree of freedom in design is large, and the auxiliary transmission 8 is provided. Can be made compact.

Further, during high-speed two-wheel drive and high-speed four-wheel drive, the high-speed chain 92 is used to reduce the frequency of use of gears, and at low speed, only low-speed gears are used. It is not necessary to increase the precision, the gear can be used for cold forging, and the cost can be reduced.

The present invention is not limited to the above-mentioned embodiment, and it is needless to say that various application and modification are possible.

For example, as shown in FIG. 6, a first intermediate shaft bearing 94 and a second intermediate shaft bearing 96 are provided on both ends of the intermediate shaft 84.
The idler gear 88 can be fixedly provided on the intermediate shaft 84 while being rotatably held by.
According to this structure, the intermediate bearing for rotatably supporting the idler gear 88 is unnecessary, and the structure can be simplified.

Further, as shown in FIG. 7, low speed transmission means 8
2 may be a low speed chain 98 wound around the low speed drive gear 46 and the low speed driven gear 64. According to this configuration, the intermediate shaft and the idler gear are unnecessary, the configuration is simplified, the degree of freedom in design is further increased, and the auxiliary transmission 8 can be made more compact.

[0039]

As is apparent from the above detailed description, according to the present invention, an input shaft to which a driving force is input is provided, and a low speed drive gear and a high speed drive sprocket are rotatably provided on the input shaft. A low-speed / high-speed switching mechanism is provided between the low-speed drive gear and the high-speed drive sprocket, and the front output shaft and the rear output shaft that is rotatable with respect to the front output shaft are provided substantially parallel to the input shaft. , A low speed driven gear is rotatably provided, a low speed transmission means for connecting the low speed driven gear and the low speed drive gear is provided, and a high speed driven sprocket is fixedly provided on the rear output shaft,
A two-wheel / four-wheel switching mechanism is provided between the high-speed driven sprocket and the low-speed driven gear, and a high-speed transmission means for connecting the high-speed driven sprocket and the high-speed drive sprocket is provided, so that high-speed two-wheel drive and high-speed Four
When the wheels are driven, the low speed drive gear and the low speed driven gear are not allowed to idle, and noise and vibration can be reduced.

Secondly, since the high speed transmission means is a high speed chain wound around the high speed drive sprocket and the high speed driven sprocket, the high speed transmission means is used for high speed two-wheel drive and high speed four-wheel drive. Since a chain is used, the structure of the gear mechanism is simplified, which allows a greater degree of freedom in design, which makes it possible to make the auxiliary transmission compact and reduce the frequency of use of gears. Precision gears are not required, and cold forged gears can be used, which can be inexpensive.

[Brief description of drawings]

FIG. 1 is a skeleton diagram of an auxiliary transmission in a high speed two-wheel drive (2H) state.

FIG. 2 is a skeleton diagram of the auxiliary transmission in a high-speed four-wheel drive (4H) state.

FIG. 3 is a skeleton diagram of the auxiliary transmission in a neutral (N) state.

FIG. 4 is a skeleton diagram of the auxiliary transmission in a low speed four-wheel drive (4L) state.

FIG. 5 is a configuration diagram of a power transmission system of a vehicle.

FIG. 6 is a skeleton diagram of an auxiliary transmission according to a modified example of the present invention.

FIG. 7 is a skeleton diagram of an auxiliary transmission according to another modification of the present invention.

FIG. 8 is a configuration diagram of a conventional auxiliary transmission.

[Explanation of symbols]

 2 vehicle 4 engine 6 transmission 8 input shaft 28 input shaft 30 front output shaft 32 rear output shaft 46 low speed drive gear 50 high speed drive sprocket 52 low speed / high speed switching mechanism 64 low speed driven gear 68 high speed driven sprocket 70 two wheels・ Four-wheel switching mechanism 82 Low speed transmission means 90 High speed transmission means

Claims (2)

[Claims] 1. An input shaft for inputting a driving force is provided, a low speed drive gear and a high speed drive sprocket are rotatably provided on the input shaft, and a low speed is provided between the low speed drive gear and the high speed drive sprocket. A high-speed switching mechanism is provided, a front output shaft and a rear output shaft that is rotatable with respect to the front output shaft are provided substantially parallel to the input shaft, and a low-speed driven gear is rotatably provided on the front output shaft. A low-speed transmission means for connecting the low-speed driven gear and the low-speed drive gear is provided, a high-speed driven sprocket is fixedly provided on the rear output shaft, and a high-speed driven sprocket is provided between the high-speed driven sprocket and the low-speed driven gear. A wheel / four-wheel switching mechanism is provided, and high-speed transmission means for connecting the high-speed driven sprocket and the high-speed drive sprocket is provided. Characteristic auxiliary transmission gear train structure. 2. The gear train structure for an auxiliary transmission according to claim 1, wherein the high-speed transmission means is a high-speed chain wound around the high-speed drive sprocket and the high-speed driven sprocket. .