JPH081251B2 - Saddle-type vehicle transmission - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a saddle-ride type vehicle transmission including a forward main transmission, a high / low speed switching mechanism, and a forward / backward switching mechanism.

(Background of the Invention) A small three- and four-wheeled vehicle in which an engine is mounted near the center of a vehicle body and a saddle-ride type driving seat is provided at the upper portion of the vehicle body. 2. Description of the Related Art Conventionally, an auxiliary gearbox for switching is known. For example, there is one in which a crankshaft is arranged in the width direction of a vehicle body, and a high / low speed switching gear or a high / low speed switching slider of an auxiliary transmission is provided on a transmission auxiliary shaft of the main transmission (Japanese Patent Laid-Open No. 59-69551, 59). −69552
No., 60-37421, etc.). However, in this case, the transmission auxiliary shaft becomes long, the case for accommodating the auxiliary transmission protrudes greatly from the crankcase in the vehicle width direction, the engine becomes large, and the foot of the driver placed on the side of the engine easily hits. was there. In addition, it is necessary to lubricate the auxiliary transmission separately from the inside of the crankcase, which causes a problem that the lubrication system becomes complicated.

Further, it has been considered to house the auxiliary transmission in a final reduction gear case on the rear wheel shaft (for example, Japanese Patent Application No. 60-18987 [Japanese Patent Application Laid-Open No. 61-178229]). However, in this case, the distance between the auxiliary transmission and the operator of the driver becomes long, and the operation system becomes long.

On the other hand, in the case where a forward / reverse switching mechanism is provided, there is one that interposes this between the speed change auxiliary shaft and the output shaft (for example, Japanese Patent Laid-Open Publication No.
60-37421). However, in this case, the gear ratio during reverse travel changes depending on the gear stage of the main transmission. For this reason, an interlock mechanism for setting the main transmission to a specific shift speed is required during reverse travel. However, if the transmission drum of the main transmission and the switching drum of the auxiliary transmission are separated, the interlock mechanism becomes large and complicated. Further, in the case where the transmission mechanism of the main transmission is a foot-operated type, it is necessary to remember the number of times of operation and recognize in which gear stage the operation is very troublesome.

(Object of the Invention) The present invention has been made in view of such circumstances,
Providing a straddle-type vehicle transmission that reduces the engine width to make the engine smaller, does not complicate the lubrication system, shortens the operation system, and does not require an interlock mechanism and is easy to operate. The purpose is to do.

(Construction of the Invention) According to the present invention, an object of the present invention is to install a crankshaft laterally mounted engine in the vicinity of the center of a vehicle body, a main transmission housed in a crankcase of the engine, and an upper vehicle body. In a transmission for a saddle-ride type vehicle including a saddle-ride type operation seat, a forward main transmission provided in a crankshaft parallel to the crankshaft and a shift countershaft in the crankcase, and the crankshaft. An output shaft that is parallel and separate from the speed change auxiliary shaft and non-coaxial, a high-low speed switching gear and a reverse gear that can idle on the output shaft, and slide on the output shaft in the axial direction. A plurality of switching sliders for transmitting the rotation of any of the gears of the gear to the output shaft, an idle shaft for transmitting the rotation of the shift main shaft to the reverse gear, and an idle shaft for transmitting the rotation of the shift main shaft to the reverse gear. Vice axis times An intermediate shaft for transmitting rotation to the high / low speed switching gear,
A gear group that transmits rotation between the output shaft, the idle shaft, and the intermediate shaft is positioned substantially within the width range of the main transmission, and the forward main transmission is a foot-operated single speed change mechanism. The present invention is achieved by a transmission device for a saddle-type vehicle, characterized in that, while shifting, a plurality of switching sliders on the output shaft are switched by one switching operating mechanism independent of the speed changing operating mechanism.

(Embodiment) FIG. 1 is a side view showing an axial arrangement of an engine which is an embodiment of the present invention, FIG.
Similarly, the figure is a sectional view taken along the line III-III in FIG. 1, and FIG. 4 is a side view of a four-wheeled vehicle for traveling on rough terrain equipped with this engine.
FIG. 5 is an overall configuration diagram of the power system.

In FIG. 4, reference numeral 10 is a body frame, 12 is a pair of left and right steering front wheels, and 14 is a pair of left and right driving rear wheels. These front wheels 12 and rear wheels 14 are wide ultra-low pressure tires (so-called balloon tires). It is installed. The rear wheel 14 is held by the vehicle body frame 10 via a rear arm 16 which can be swung up and down. That is, the front end of the rear arm 16 is the body frame 10
Is pivotally supported by a pivot shaft 18, a rear wheel shaft 20 is held at its rear end, and rear wheels 14 are fixed to both ends of the rear wheel shaft 20, respectively. A shock absorber 22 supports the rear arm 16. 24 is an engine mounted near the center of the vehicle body, 26 is a front fender, 28 is a rear fender, 30 is a steering bar handle, and
Reference numeral 32 is a straddle-type driving seat disposed on the upper part of the vehicle body.

As shown in FIGS. 1, 2, and 5, the engine 24 is disposed in the width direction of the vehicle body between the left and right divided crankcases 24a and 24b, and the crankshaft 34, and a transmission main shaft arranged in parallel with the crankshaft 34. 36, a speed change auxiliary shaft 38, an intermediate shaft 40, an output shaft 42 and an idle shaft 44. The rotation of the crankshaft 34 is mediated by a centrifugal automatic clutch 46 for starting and a reduction gearwheel 48 at the right end of the crankshaft 34.
It is transmitted to the reduction gear 50 and the shift clutch 52 provided on the 36. Main shaft 36 and counter shaft 3 in crankcases 24a, 24b
A gear group that forms a known constant mesh type main transmission 54 is mounted on the 8 and the rotation of the main shaft 36 is transmitted to the sub shaft 38 via the main transmission 54. The speed change clutch 52 is disengaged during speed change in conjunction with the speed change operation of the main transmission 54 and is normally engaged.

The intermediate shaft 40 has gears 56, 58 with different numbers of teeth that rotate together.
Is rotatably held, and these gears 56 and 58 are also connected to the output shaft 4
It meshes with the high / low speed switching gears 60, 62 which are rotatably held by 2. A high-speed switching slider 64 that forms a dog clutch together with the high-speed gear 60 is provided between the two gears 60 and 62.

A reverse gear 66 is also held on the output shaft 42 in a freely rotatable manner. Between the gear 66 and the high / low speed switching gear 62 on the low speed side, a forward / reverse switching slider 68 that forms a dog clutch together with the gears 66, 62 is provided. Gears 70 and 72 provided on the idle shaft 44 transmit the rotation of the transmission main shaft 36 to the reverse gear 66.

The high-low speed switching gears 60, 62, the reverse gear 66, the sliders 64, 68, etc., which transmit the rotation between the output shaft 42, the idle shaft 44, and the intermediate shaft 40, are arranged in a crank group as shown in FIG. It is housed in the cases 24a, 24b and is located within the width of the main transmission 54.

In FIG. 1, reference numeral 74 is a forward shift cam drum, and shift forks 76 and 78 are engaged with cam grooves formed on the peripheral surface thereof. These shift cam drums 74 and shift forks
76, 78, etc. constitute a gear shift operation mechanism. A foot-operated shift pedal 80 (Fig. 4) rotates the shift cam drum 74,
As a result, the shift forks 76, 78 move to shift the main transmission 54.

Next, based on FIGS. 1 and 4, an auxiliary transmission for performing high / low speed switching and forward / reverse switching will be described. In these figures, 82 is a switching lever, which is the crankcase 24a on the left side of the engine 24.
It is provided on the top so as to be rotatable in the front-rear direction. A switching drum 84 as a high / low speed switching cam is disposed above and behind the crankcases 24a, 24b, that is, diagonally above and behind the output shaft 42 (Figs. 1 and 3). The switching drum 84 has a link 86. It is rotated by the switching lever 82 via the. This switching drum 84
Has two cam grooves, and the switching forks 88, 90 are guided by the cam grooves to move. These switching forks 8
8, 90 are engaged with the sliders 64, 68 on the output shaft 42, and the movement of the forks 88, 90 causes the sliders 68, 80 to move. The switching drum 84, the switching forks 88, 90, etc. form a switching mechanism.

Now, when the switching lever 82 is set to the intermediate front-rear high speed position H (FIG. 1), only the slider 64 on the output shaft 42 engages with the high speed side gear 60, and the other sleeve 68 moves from the gears 62 and 66. Keep disengaged. Therefore, if the rotation of the crankshaft 34 rises and the starting clutch 46 is engaged, the rotation of the crankshaft 34 is transmitted to the main shaft 36, and the gears on the main transmission 54 and the intermediate shaft 40 are further transmitted.
It is transmitted to the output shaft 42 through 58, 56 and the forward gear 60 on the high speed side. The rotation of the output shaft 42 is transmitted to the rear wheel shaft 20 via a bevel gear 88, a final shaft 90, a propeller shaft 92 and a final reduction gear 94 (Fig. 5), and the vehicle moves forward. If you operate the shift pedal with your foot, the transmission clutch 52 will be disengaged first, and then the transmission
When the gear shift 54 is performed and the shift pedal 80 is returned, the clutch 52 is re-engaged.

When the switching lever 82 is tilted forward to the forward low speed position L, the slider 64 on the output shaft 42 is disengaged from the gear 60, and the slider 68 is engaged with the low speed gear 62. As a result, the vehicle speed is reduced and the vehicle can move forward with a large driving force.

When the switching lever 82 is pulled backward to switch to the reverse position R, the slider 68 on the output shaft 42 is disengaged from the gear 62, and the slider 68 engages with the reverse gear 66. Therefore, the rotation of the main shaft 36 depends on the reverse gears 70, 72 and the reverse gear 66 of the idle shaft 44.
Is transmitted to the output shaft 42 via and, and the vehicle moves backward.

In this embodiment, the starting clutch 46 is provided in front of the shifting clutch 52.However, the starting clutch 46 is omitted, and the shifting clutch 52 is configured by a manual clutch so that the starting clutch is also used by the manual clutch. Of course, it is good.

(Effects of the Invention) As described above, the present invention provides the intermediate shaft, the idle shaft, and the output shaft separately from the speed change auxiliary shaft, and the high-low speed switching gear and the reverse gear in the crankcase portion on the output shaft. , A plurality of switching sliders for performing high / low speed switching and forward / backward switching are provided, and a gear group for transmitting rotation between these output shafts, idle shafts, and intermediate shafts is almost within the width range of the main transmission. Since it is located, the width of the crankcase of the engine is narrowed and the engine can be downsized. Further, since the switching mechanism for high speed / low speed and forward / backward movement is provided in the crankcase, it is not necessary to separately provide a lubricating system, which simplifies the lubricating system.

Further, since a plurality of sliders are collectively provided only on the output shaft, the positions of the switching mechanism for moving these sliders, that is, the positions of the switching fork and the switching drum can be arbitrarily determined within a relatively wide range around the output shaft. Greater freedom of placement. Therefore, it is also suitable for downsizing the engine.

When the vehicle is traveling in reverse, the rotation of the transmission main shaft bypasses the main transmission and is transmitted to the output shaft via the idle shaft, so that the gear ratio is always a predetermined gear ratio regardless of the gear stage of the main transmission. Therefore, an interlock mechanism between the forward / reverse switching mechanism and the main transmission is unnecessary. Therefore, the degree of freedom in arranging the switching operation mechanism of the auxiliary transmission is increased with respect to the position of the shift operation mechanism of the main transmission.

Further, the foot-operated transmission mechanism of the main transmission requires a number of operations to be remembered in order to recognize the shift speed, and the operation is troublesome. Regardless of whether or not there is a constant gear ratio, the operation is easy.

Furthermore, since the plurality of switching sliders are inside the crankcase, the distance to the driver is reduced and the operating system thereof is shortened. Further, since the crankcase width does not become excessively large, it is possible to easily cope with the case where the transmission system for transmitting the rotation of the output shaft to the rear wheels is a chain and the case where the transmission system is a propeller shaft.

[Brief description of drawings]

FIG. 1 is a side view showing an axial arrangement of an engine which is an embodiment of the present invention, FIG. 2 is a developed view in which a part thereof is sectioned, and FIG. 3 is a sectional view taken along line III-III in FIG. FIG. 4 is a side view of a four-wheeled vehicle for traveling on rough terrain equipped with this engine, and FIG. 5 is an overall configuration diagram of its power system. 24 ... Engine, 24a, 24b ... Crankcase, 32 ... Saddle-type operating seat, 34 ... Crankshaft, 40 ... Intermediate shaft, 42 ... Output shaft, 44 ... Idle shaft, 54 ... Main transmission, 60, 62 ... High Low speed switching gear, 64 ... High / low speed switching slider, 66 ... Reverse gear, 68
... forward / backward switching slider, 74 ... speed change drum that constitutes a speed change operation mechanism, 84 ... switch drum that constitutes a speed change operation mechanism.

Claims (1)

[Claims] 1. A crankshaft laterally mounted engine mounted in the vicinity of the center of a vehicle body, a main transmission housed in a crankcase of the engine, and a saddle-ride type driving seat disposed on an upper portion of the vehicle body. In a straddle-type vehicle transmission, a forward main transmission provided on a transmission main shaft and a transmission auxiliary shaft that are parallel to the crankshaft, and a forward transmission separate from the transmission auxiliary shaft that is parallel to the crankshaft in the crankcase. And a non-coaxial output shaft, a high / low speed switching gear and a reverse gear that can idle on this output shaft, and slides in the axial direction on the output shaft to output the rotation of any of the gears on the output shaft. A plurality of switching sliders for transmitting to the shaft, an idle shaft that is parallel to the crankshaft and transmits the rotation of the transmission main shaft to the reverse gear.
A gear group that includes an intermediate shaft that is parallel to the crankshaft and that transmits the rotation of the speed change auxiliary shaft to the high / low speed switching gear, and that transmits a rotation between the output shaft, the idle shaft, and the intermediate shaft. Of the plurality of switching sliders on the output shaft independent of the shift operating mechanism while the forward main transmission is shifted by one foot-operated shift operating mechanism. A straddle-type vehicle transmission characterized by being switched by a switching operation mechanism.