JPH0219651Y2 - - Google Patents

Description

[Detailed description of the invention] <Industrial application field> The present invention relates to a mechanical continuously variable transmission device that can switch forward and backward for a passenger working vehicle. Regarding.

<Prior Art> When a work implement is attached to a passenger traveling work vehicle, there are two cases: the work implement is attached to the front or rear part of the vehicle body via a link mechanism, and the latter is attached to the abdomen of the vehicle body via a ring mechanism.

That is, when a working machine D represented by a mower is attached to a tractor T, which is a passenger vehicle, as shown in FIG.
Usually, the working machine D is installed as shown in the figure.

By the way, since the tractor T needs to travel by frequently repeating forward and backward movement, and the traveling speed is also required to be stepless, a hydraulic transmission mechanism M is interlocked with the rear side of the installed engine E, and the hydraulic A speed reduction mechanism G is interlocked and connected to the speed change mechanism M, and the driving wheels E are driven through the speed reduction mechanism G.

<Problems to be solved by the invention> In the conventional example described above, the engine E, the continuously variable transmission mechanism M, and the reduction mechanism G are arranged in parallel in the front and rear, and the wheelbase L becomes large, resulting in a small turning performance. There was a problem that there was a lack of

In addition, when the working machine M is mounted on the front and rear, a so-called overhang occurs, and the turning performance becomes increasingly poor, and this is a step forward in particular for a transmission device that requires small turning performance, such as a mower.

<Means for solving the problem> The present invention solves the problems of the conventional example described above. Therefore, in the present invention, a mechanical continuously variable transmission mechanism driven by an engine is provided. is,
An axle having a drive wheel of a traveling work vehicle is driven through a forward/reverse switching mechanism interlocked with the continuously variable transmission mechanism, and a driven wheel is provided having a wheelbase with the drive wheel, wherein the engine is mounted on one end of the front or rear of the vehicle body, a transmission case is attached to the bottom side of the engine, and a continuously variable transmission mechanism and a forward/reverse switching mechanism are installed in parallel in the front and rear of the transmission case. , the interlocking shaft systems of the two mechanisms are provided below the output shaft of the engine and axially parallel to the output shaft, and further, the output shaft system of the forward/reverse switching mechanism is below the interlocking shaft system and the interlocking shaft The output shaft system is interlocked with an axle having a drive wheel that is provided in parallel with the drive wheel in the axial direction and supported by the transmission case, and is located between the drive wheel and the driven wheel and in the vicinity of the engine. The present invention provides a mechanical continuously variable transmission device capable of switching forward and backward movement of a passenger working vehicle, characterized in that a driver's seat is provided in the front and rear of the vehicle.

<Embodiment> Figures 1 to 6 show a first embodiment of the present invention and its operating mechanism, in which 1 is a riding work vehicle;
It includes a pair of left and right front wheels 2 that serve as steering wheels, and a pair of left and right rear wheels 3 that serve as driving wheels.

The vehicle body 4 of the work vehicle 1 has a frame structure, and a steering mechanism 5 is installed at the front of the vehicle body 4 in a rearwardly inclined manner, and the steering mechanism 5 steers the front wheels 2 via a transmission means (not shown). It is possible.

An engine 6 is mounted on the rear upper surface of the engine 4, and the engine 6 is covered with an engine cover 7. In this example, a driver's seat 8 is mounted on the middle upper surface of the engine cover 7.
is provided.

Thus, the operator on the driver's seat 8 can steplessly switch the rear wheels 3, which are the driving wheels, back and forth by operating the pedal-type operating mechanism 10 on the step section 9 with his/her feet, and the steering mechanism 5. The front wheels 2 can be steered via the front wheels.

A transmission case 11 is attached to the lower surface side of the engine 6, and in this example, the transmission case 11 is attached to the lower surface side of the vehicle body 4 or to the inner surface side of the front-rear frame of the planar longitudinal frame that constitutes the vehicle body 4 (not shown). is supported by the mounting structure.

Here, the engine 6 and the transmission case 11 are arranged vertically, and in plan view, the engine 6 and the transmission case 11 are overlapped and housed within the frame of the vehicle body 4.

The output shaft 12 of the engine 6 is the flywheel 6A
The output shaft 12 is projected forward through the vehicle body 4.
A drive pulley 13 is attached at the center of the width.

Inside the transmission case 11 is a friction continuously variable transmission mechanism 14.
and a gear-based forward/reverse switching mechanism 15 are installed in parallel in the front/rear direction and are supported internally.
5 are interlocked and connected by an interlocking shaft system 16 on the same axis, and the interlocking shaft system 16 is located below the output shaft 12 of the engine 6 and is in a parallel relationship with the same axial direction.

That is, the interlocking shaft system 16 is composed of an input shaft 17 and an output shaft 18 of the continuously variable transmission mechanism 14, which are supported via bearings 19 and 20, respectively. Driven pulleys 21 and 22 are attached to the protruding portions, and these pulleys 22 and 22 and the aforementioned driving pulley 13
A winding transmission mechanism 25 is constructed by winding belts 23 and 24 around these, respectively.

The driven pulley 22 is supported by the input shaft 17 via a bearing 26 so that the two can rotate freely, and the pulley 21 is provided with a joint portion 21A on the front surface.

The other driven pulley 22 is attached to the input shaft 17 via a key or spline.

A working machine 27 represented by a mower is supported on the vehicle body 4 between the front wheels 2 and rear wheels 3 via a link mechanism 28 so as to be able to be raised and lowered.
9 and a power receiving part 30, and the receiving part 30 and the joint part 21A are connected to a universal joint shaft 31.
The cutting blade body 29 is rotatable around the vertical axis by being connected by.

Note that the work implement 27 can be freely removed from the vehicle body 4 with respect to the link mechanism 28 or each link mechanism 28.

As the continuously variable transmission mechanism 1, for example, a friction continuously variable transmission disclosed in Japanese Patent Publication No. 57-13221 can be adopted. However, a continuously variable transmission composed of other friction rollers, disks, etc. may also be used.

The continuously variable transmission mechanism 14 of this example has the structure disclosed in the above-mentioned publication, and includes a raceway ring 33 attached to the input shaft 17 via a thrust bearing 32, a plurality of conical rotors 34 arranged radially, a speed change ring 35 frictionally engaged with the conical surface 34A of the trochanter 34;
It consists of a cylindrical body 36 attached to the output shaft 18 that is frictionally engaged with the second annular transmission surface 34C of the trochanter 34, and a cylindrical body 36 attached to the output shaft 18 that is frictionally engaged with the second annular transmission surface 34C of the trochanter 34. By sliding it in the direction (left and right in FIG. 2), the first part of the trochanter 34 is
The outer peripheral edge of the raceway ring 33 is on the annular transmission surface 34B,
Since the outer periphery of the cylinder 36 is frictionally engaged with the second annular transmission surface 34C, continuously variable speed in one direction including neutral (stop) is possible.

The forward/reverse switching mechanism 15 includes a sliding gear 37 slidably fitted onto the output shaft 18 via a spline, and a large diameter gear mounted on an intermediate shaft 38 installed on the side of the output shaft 18. 39A and a small diameter gear 39B, and a transmission gear 42 on a wheel drive shaft, i.e., an output shaft system 41, which in this example has a bevel pinion supported via a bearing 40 below the output shaft 18. The transmission gear 42 and the small diameter gear 39B of the reverse gear 39 are engaged with each other, and the sliding gear 37 can be selectively engaged with the transmission gear 42 and the large diameter gear 39A of the reverse gear 39. .

The wheel drive shaft, that is, the bevel pinion of the output shaft system 41 is engaged with the crown gear 42A of the differential mechanism 42, and the differential output shaft that is linked to the rear wheels is an axle 43, and the rear wheels are switched between forward and backward directions. It is said that it can be driven freely.

A conversion mechanism 43 is connected to the continuously variable transmission mechanism 14, and a conversion mechanism 44 is connected to the forward/reverse switching mechanism 15.
It is linked to 0.

The conversion mechanism 43 for continuously variable transmission includes a shifter 46 having a fan-shaped member 45 engaged with the speed change ring 36, the shifter 46 being slidably fitted on the shift rod 47, and further having a winding section on the rod 47. A neutral return spring 48 biases the shifter 46 in the neutral direction.

Then, the lower arm 49A of the vertical shaft 49 supported by the lid 11A of the transmission case is engaged with the engaged portion 46A of the shifter 46, and the upper arm 49A of the vertical shaft 49 is engaged with the engaged portion 46A of the shifter 46.
9B is installed.

Further, the conversion mechanism 44 for switching forward and backward travel includes a shift fork 50 that is engaged with a sliding gear,
Upper and lower arms 53A, 53B are attached to a vertical shaft 52 supported by the lid 11A, and the lower arm 53A is connected to the shift fork 50.
It is configured to be engaged with the engaged portion 50A of.

As shown in FIGS. 3 and 5, the pedal-shaped operating mechanism 10 includes a pedal shaft 55 that is attached to a fixing member 54 on the vehicle body 4 side in the transverse direction (vehicle width direction), and a pedal shaft 55 that is fitted onto the pedal shaft 55. tread portions 56A, 5 at the front and rear.
6B, and an arm 57 projecting downward from the boss of the pedal 56, the arm 57 and the upper arm 53B of the conversion mechanism 44 are connected via a rod 59 having a relay link 58 in between, respectively. They are interlocked and connected by pins 60 and 61.

Further, a shaft 63 is provided on one side of the pedal 56 and is rotatably supported by a fixed cylinder 62 in the front-rear direction. A pair of front and rear arms 65 and 66 facing each other is provided, and a downward arm 67 is attached to the shaft 63.
In this example, the upper arm 49B of the conversion mechanism 43 is interlocked with a pin 69 and a nut 70 via a Bowden wire 68 that can be transmitted in the push/pull direction.

Therefore, in this embodiment, when the pedal 56 is depressed in either direction indicated by the arrows a or b in FIG.
is slid as indicated by the arrow c in FIG. 6, and can be selected either forward or backward.
The pedal force is not transmitted to the arms 65, 66. That is, the continuously variable transmission mechanism 14 is maintained neutrally within the forward/reverse switching range.

Further, when the pedal 56 is depressed in the direction indicated by the arrows a and b, the tread surface of the pedal 56 comes into contact with either the arm 65 or 66, and the pedal force (operating force) is transferred to the conversion mechanism 43 via the Bowden wire 68. shifter 46
Slide the gear ring 3 in the direction of arrow d in Fig. 6.
5 is slidable, and the gears can be changed steplessly including neutral.

Here, the gap 64 constitutes a selection tolerance range for forward/reverse switching, and this tolerance range may be constituted by slack in the Bowden wire 68 or play in the pin 60 or nut 70 (for example, a long hole).

<Effect of invention> The present invention is as described above, and has the following advantages.

A transmission case 11 is attached to the lower surface side of the engine 6, and a continuously variable transmission mechanism 14 and a forward/reverse switching mechanism 15 are provided in the transmission case 11. Interlocking shaft system 16
Because of the so-called vertical arrangement provided below, the wheelbase of the traveling working vehicle 1 can be shortened, and it can be made to have excellent turning performance.

In addition, since the continuously variable transmission mechanism 14 and the forward/reverse switching mechanism 15 in the transmission case 11 are arranged side by side in the longitudinal direction, the wheelbase (wheelbase) mentioned above can be secured while the vehicle width can be made compact without becoming too large. can.

Furthermore, the engine 6 and the transmission case 11 are arranged vertically, and the transmission case 11 supports the axle 43 having the drive wheels 3, so the drive wheels 3 include the engine 6, the continuously variable transmission mechanism 14, and the forward/reverse switching mechanism. 15 is applied to the transmission case 11, which increases the traction force of the drive wheels 3 and improves driving performance. Also, since the driver's seat 8 is provided near the engine 6, the drive wheels 3, the driver's weight also acts to increase the traction force.
Since the driver's seat 8 is provided between the driven wheels 2 and the driving wheels 3, the front-rear balance is not significantly affected by the weight of the driver, and the vehicle can be made compact.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; Fig. 1 is an overall side view of the first embodiment mounted on a traveling work vehicle, Fig. 2 is an elevational sectional view of the inside of the transmission case, and Fig. 3 shows the operating mechanism together. Fig. 2 is a diagram indicated by the arrows A-A in Fig. 2, Fig. 4 is a diagram indicated by the arrows B-B in Fig. 2, Fig. 5 is a front view of the operating mechanism, and Fig. 6 is a diagram indicated by the arrows C-C in Fig. 2. , FIG. 7 is a side view of the conventional example. 1... Traveling work vehicle, 6... Engine, 14...
Continuously variable transmission mechanism, 15... Forward/forward switching mechanism, 16...
...Interlocking shaft system, 41...Output shaft system, 43...Axle.

Claims (1)

[Claims for Utility Model Registration] A mechanical continuously variable transmission mechanism 14 driven by an engine 6 is provided, and the traveling work 1 is driven through a forward/reverse switching mechanism 15 interlocked with the continuously variable transmission mechanism 14. In a vehicle in which an axle 43 having wheels 3 is driven and a driven wheel 2 is provided with a bearing distance from the driving wheel 3, the engine 6 is mounted on one end side of the front or rear of the vehicle body 4, and the engine 6 A transmission case 11 is attached to the lower surface side of the transmission case 11, and a continuously variable transmission mechanism 14 and a forward/reverse switching mechanism 15 are provided in the transmission case 11 in parallel in the front and back. 16 is provided below the output shaft 12 of the engine 6 and axially parallel to the output shaft 12, and furthermore, the output shaft system 41 of the forward/reverse switching mechanism 15 is provided below the interlocking shaft system 16 and in parallel with the output shaft 12. 16 and is provided axially parallel to the drive wheel 3 and is supported by the transmission case 11. The output shaft system 41 is interlocked with the axle 43, and the drive wheel 3 is connected between the driven wheel 2 and the drive wheel 3. A mechanical continuously variable transmission device for a passenger working vehicle capable of switching forward and backward movement, characterized in that a driver's seat 8 is provided near the engine 6.