JPH0240138B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a gear transmission device suitable for small vehicles such as automobiles and tricycles.

(Prior art) A gear transmission device for a vehicle has a main shaft driven by a crankshaft, a countershaft arranged in parallel, and a plurality of driving and driven gears arranged on each shaft.
A shifter provided between the gears on the shaft is moved by a shift fork, any one of the plurality of gears is connected to the countershaft, and the speed is changed to a desired reduction ratio and outputted.

In such a transmission, the reverse gear for reversing is driven in reverse through the idle gear on the countershaft.

(Problems to be Solved by the Invention) In the above conventional technology, generally a single-stage idle gear is used, and there is a limit to the setting of the reduction ratio. As a result, there is a restriction on the shortening of the distance between the idle shaft and the countershaft, etc., so there is room for improvement, such as the transmission case becoming somewhat larger.

(Objective of the Invention) The present invention has been made to improve the above-mentioned problems.The purpose of the present invention is to set the reduction ratio adequately and arbitrarily in a small space, and to provide a system for a reverse idle gear. The shaft position can be set arbitrarily, the distance between the shafts can be shortened and the transmission can be made more compact. Furthermore, the number of man-hours required for machining the main shaft gear can be reduced, the strength of the gear can be improved, and the gear To provide a gear transmission that does not require an escape space between them.

(Means for Solving the Problems) The present invention aims to solve the problems of the prior art as described above, and also to achieve the above objects. A reverse driven gear is provided on the counter shaft, the reverse drive gear and the super low drive gear are integrally provided on the main shaft, and the low drive gear that meshes with the drive gear is connected to the counter shaft. A two-stage speed reduction gear provided on the shaft adjacent to the reverse driven gear and comprising a small diameter gear that meshes with the reverse driven gear and a large diameter gear that meshes with the integrated drive gear. An idle gear having a configuration is provided, a part of the side surface of the large diameter gear is brought close to the side surface of the row driven gear, and the reverse driven gear or the row driven gear is further provided at a position facing the large diameter gear. A shifter is provided to engage and disengage the countershaft.

(Effects of the above means) Since the idle gear has a two-stage structure with large and small diameters as described above, the arrangement of the idle shaft can be made arbitrary, and the distance between the shafts can also be shortened, making it possible to miniaturize the idle gear and set a large reduction ratio as desired. can be obtained. Since the shifter is disposed within the width of one gear of the idle gear, one gear can be made larger to increase the reduction ratio while securing space for the gear.
The distance between the shafts can be shortened and the transmission can be made more compact. In addition, since the reverse drive gear and the super row drive gear are integrated on the main shaft, the number of man-hours required for machining the gears on the main shaft can be reduced.
Furthermore, the strength of the drive gear is improved, and there is no need to provide escape space between the gears.

(Embodiment) Next, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a cross-sectional view of the transmission including a part of the engine, and FIG. 2 is an exploded cross-sectional view of the same main part viewed from a different angle.

1 is the transmission case including the crankcase,
Reference numeral 2 denotes a crankshaft horizontally suspended on the crankcase, and a main shaft 3 is arranged parallel to and adjacent to the crankshaft 2, and a countershaft 4 is arranged parallel to and adjacent to the main shaft 3. and each shaft 3, 4 has a bulkhead 10
1 and 102 via bearings 501 to 504 so as to be rotatable. Main shaft 3 has bearing 5
01 Receives power from one end of the crankshaft 2 via a clutch mechanism 6 attached to the outward extension,
7 in the figure is the ACG installed at the other end of the crankshaft.

In the portion between the bearings 501 and 502 arranged apart in the axial direction on the main shaft 3, from the middle part to the one end side, a first speed drive gear 301, a third speed drive gear 303, a second speed drive gear 302, The 4th speed drive gear 304 is sequentially arranged, and the 1st speed drive gear 30
1 has a large reduction ratio and a small diameter, so it is machined and integrally formed on the main shaft 3, and other gears 3
Nos. 02, 303, and 304 have successively smaller reduction ratios and larger diameters, so separate parts were fixed on the shaft by spline fitting or the like.

On the countershaft 4 are each of the gears 301 to 301.
Driven gears 401 to 404 that mesh with each of 304
The first speed driven gear 401 meshes with the first speed drive gear 301, the second speed driven gear 402 meshes with the second speed drive gear 302, and the third speed driven gear 40 meshes with the second speed driven gear 401.
The third and fourth speed driven gears 404 mesh with the third speed drive gear 303 and the fourth speed drive gear 304, respectively.
The above-mentioned driven gears 401 to 404 are rotatably engaged on the countershaft 4, and are connected to the main shaft 3.
The rotation of the drive gears 301 to 304 causes the drive gears 301 to 304 to constantly idle, and the axial movement of the shifter 8 causes the driven gears 401 to 40 to idle.
4 is engaged with the countershaft 4 to drive it.

1st gear gear 301 on the main shaft 3 above
and the bearing 501 on the clutch mechanism 6 side, there is a lowest speed drive gear that has a smaller diameter than the first speed drive gear 301, that is, a larger reduction ratio, i.e., a super low drive gear 305 that has a larger reduction ratio than the first speed drive gear. is integrally formed on the shaft 3 by gear cutting, and the row drive gear 305 is set to have a tooth width that is more than twice the tooth width of the driven gear driven by the row drive gear 305.

The 1st speed driven gear 4 on the countershaft 4
01 and the bearing 503 on the clutch mechanism side,
First, place the driven gear 4 for the row near the bearing 503 side.
05 is rotatably supported loosely, and the gear 405
is meshed with a portion 305a of the drive gear 305 that occupies approximately 1/2 of the tooth width near the bearing 501,
Since the gear has a large reduction ratio, it is set to have a large diameter.

The 1st speed driven gear 4 on the countershaft 4
A retraction gear 9, that is, a reverse gear 9, is rotatably and loosely supported between the driven gear 405 and the row driven gear 405. The reverse gear 9 is close to the first speed driven gear 401, and its teeth are similar to the described low drive gear 30.
Coaxial row driven gear 4 facing outward in the axial direction of 5
05, but spaced apart from each other in the axial direction. The gear 9 has a large diameter because it has a large reduction ratio.

A reverse idle shaft 10 is disposed parallel to and adjacent to the main shaft 3 and the counter shaft 4.
A reverse idler 11 is rotatably supported. The idle gear 11 includes integral two-stage gear portions 111 and 112 having different large and small diameters. The large diameter gear portion 111 is meshed with the other portion 305b of the row driven gear 305 described above, and the small diameter gear portion 112 with a large reduction ratio is meshed with the reverse gear 9. As a result, the rotation of the main shaft 3 rotates the row driven gear 405 in the forward direction via the gear 305, and also drives the reverse gear 9 via the idle gear 11.
will be rotated in the opposite direction.

A part of the side surface of the idle idle gear portion 111 of the above idle gear 11 is located between the reverse gear 9 and the low driven gear 405.
5.

A shifter 12 is disposed between the reverse gear 9 on the counter shaft 4 and the row driven gear 405 so as to be slidable only in the axial direction by spline fitting, etc., and a part of the axial end surface of the shifter 12 has an engaging protrusion. Part 121, 12
2 protruding in both axial directions. Engagement recesses 901 and 406 made of holes or the like are provided in part of the bases of the reverse gear 9 and the row driven gear 405. Idle large diameter gear portion 111 of the idle gear 11
The tips of the teeth face close to the outside of the shifter 12, and the shifter 12 is disposed within the width of the gear portion 111.

In addition, 13 in the drawing is the spindle for the kick starter.
131 is a gear driven by this, 132 is an idle gear for the kick starter, which meshes with a driven gear 133 provided outside the bearing 501 of the main shaft 3.
The crankshaft 2 is driven via the clutch mechanism to perform starting using the kick starter. Also 14
is a final gear box, which drives a drive shaft (not shown in the embodiment) via an internally installed final gear 141, and this gear 141 meshes with a drive gear 407 provided at the shaft end of the countershaft 4. It receives a variable speed output.

In the above, the gears 405 and 9 are rotationally driven as described above, and the shifter 12 is rotated by the countershaft 4.
In the above figure, by moving to the right or left in the figure, either of the engagement protrusions 121, 122 engages with one of the engagement recesses 901, 406 of the gears 9, 405, thereby causing the countershaft 4 to The forward or reverse rotation power is transmitted, causing the vehicle to run in the low or reverse direction.

In the above embodiments, the gear 405 has been described as the lowest speed super low gear, but the point is that this is the 1st speed, and the 1st through 4th speeds described above are actually the 2nd through 5th speeds.

(Effects of the Invention) According to the present invention as described above, since the idle gear has a two-stage configuration, the reduction ratio can be arbitrarily set to a large value, and the gear has a two-stage configuration to increase the reduction ratio while shortening the distance between the shafts. Since the shifter is provided within the width of one of the gears, the gear and shifter can be brought closer together, and the space outside the shifter can be effectively utilized to further shorten the distance between the shafts and make the entire transmission more compact. I can figure it out. In addition, the drive gear for reverse and the drive gear for super row are integrated on the main shaft, reducing the number of man-hours required for machining the gears on the main shaft.Also, the strength of the drive gear is improved, and there is no escape space between the gears. There is no need to provide

The present invention has many advantages as described above.

By the way, in the embodiment, driven gears for reverse and first speed with similar diameters and reduction ratios are installed adjacently on the countershaft, a shifter is installed between them, and the above-mentioned driven gears are installed between the gears outside of the shifter. Since the large diameter gear of the idle gear is made to face, the space between the driven gears can be effectively used outside the shifter, and the above effect can be more reliably exerted. Since the large-diameter driven gears are provided adjacent to each other, the entire transmission can be made more compact by only increasing the size of this portion of the transmission case.

[Brief explanation of drawings]

Figure 1 is an expanded cross-sectional view of the main parts of the mission, Figure 2
The figure is a cross-sectional view of the entire transmission including part of the engine. In the drawing, 1 is a transmission case, 3 is a main shaft, 305 is a drive gear, 4 is a countershaft, 9 is a reverse driven gear, 11 is an idle gear, 111 and 112 are two-stage gears, and 12 is a shift. .

Claims (1)

[Scope of Claims] 1. A gear transmission device for a vehicle in which a drive gear for reverse is provided on a main shaft in a transmission case, and a driven gear for reverse is provided on a countershaft, wherein the reverse drive gear is provided on the main shaft. A driving gear for a row and a driving gear for a super row are provided integrally, a driven gear for a row meshing with the driving gear is provided on the counter shaft adjacent to the driven gear for reverse, and a driven gear for a row for meshing with the driving gear is provided adjacent to the driven gear for reverse, An idle gear with a two-stage gear configuration for reduction is provided, which includes a small-diameter gear that meshes with the gear and a large-diameter gear that meshes with the integrated driving gear, and a part of the side surface of the large-diameter gear is connected to the driven gear for rowing. A gear transmission device characterized in that a shifter for engaging and disengaging the reverse driven gear or the row driven gear and the countershaft is disposed at a position close to a side surface and facing the large-diameter gear.