JP2834335B2 - Power transmission structure in work vehicle - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power transmission structure for a working vehicle such as an agricultural tractor or a lawn mower, and more particularly, to a frictionless stepless transmission that continuously changes input rotational power using a taper cone. A mechanism is provided so as to be able to transmit the shifting power to the main shaft, and an intermediate shaft arranged in parallel with the main shaft, and a power transmission between the intermediate shaft and the main shaft and a forward / reverse rotation capable of switching the rotational power between forward and reverse. The present invention also relates to a power transmission structure in a work vehicle provided with a switching mechanism, and further comprising a differential mechanism for an axle disposed in parallel with the main shaft and the intermediate shaft capable of transmitting power.

[0002]

2. Description of the Related Art Conventionally, in a power transmission structure of a work vehicle of this type, for example, as shown in FIGS.
The friction type continuously variable transmission mechanism 41, the forward / reverse rotation switching mechanism 42, and the differential mechanism 43 are housed in one case 44, and the forward / reverse rotation switching mechanism 42 is positioned so that the output of the friction type continuously variable transmission mechanism 41 to the main shaft 45 is set aside. The differential mechanism 4 from the intermediate shaft 46.
The transmission mechanism 47 to the third shaft 3 is located on the side of the intermediate shaft 46 away from the friction type continuously variable transmission mechanism 41 with respect to the forward / reverse switching mechanism 42.

[0003]

Therefore, in the above-mentioned conventional structure, the power transmission structure is provided such that a friction type continuously variable transmission mechanism 41, a forward / reverse switching mechanism 42, and a differential mechanism 43 are arranged side by side in order from the front. For this reason, the width of the right and left becomes large, and a large space for disposing the power transmission structure in the work vehicle must be ensured. There was room for improvement in reducing the size of the.

[0004] The present invention has been made in view of the above circumstances, and has as its object to provide a power transmission structure in a work vehicle in which the entire structure can be made compact by simple modification.

[0005]

A power transmission structure in a working vehicle according to the present invention includes a friction-type continuously variable transmission mechanism for continuously changing the input rotational power using a taper cone.
An intermediate shaft disposed in parallel with the main shaft, and a forward / reverse switching mechanism capable of transmitting power between the intermediate shaft and the main shaft and switching the rotational power between forward and reverse. A power transmission structure for a work vehicle in which a differential mechanism of an axle disposed in parallel with the main shaft and a power transmission of the intermediate shaft are provided, wherein the friction type continuously variable transmission mechanism and the forward / reverse rotation switching mechanism are provided. Are disposed so as to face each other in the axial direction of the main shaft, and the forward / reverse switching mechanism and the differential mechanism are disposed so as to partially overlap each other when viewed in the axial direction. The friction type continuously variable transmission mechanism and the differential mechanism are arranged on the same side of the main shaft with respect to the forward / reverse switching mechanism in the axial direction of the main shaft. Next action from the configuration Achieve the results.

[0006]

In other words, since the friction type continuously variable transmission mechanism and the differential mechanism are arranged in the same direction in the axial direction of the main shaft with respect to the forward / reverse switching mechanism, the friction type continuously variable transmission mechanism is viewed from the front. Since the mechanism and the differential mechanism can be arranged so as to overlap with each other, the left and right width of the power transmission structure can be reduced accordingly. Further, the frictionless continuously variable transmission mechanism and the forward / reverse switching mechanism are disposed so as to face each other when viewed in the axial direction of the main shaft, and the forward / reverse switching mechanism and the differential mechanism are partially disposed in the axial direction. By arranging them in an overlapping state, a friction type continuously variable transmission mechanism, a forward / reverse switching mechanism, and a differential mechanism can be arranged so that the main shaft, the intermediate shaft and the axle are as close as possible. The size of the transmission in the installation direction can be made as small as possible.

[0007]

Therefore, the differential mechanism is arranged on the same side as the friction type continuously variable transmission mechanism with respect to the forward / reverse switching mechanism, and the friction type continuously variable transmission mechanism, the forward / reverse switching mechanism and the differential mechanism are arranged on the shaft center. The simple modification that the power transmission structure is partially overlapped with each other when viewed from the direction reduces the width of the power transmission structure in the right and left direction and the width of the power transmission structure in the direction in which the main shaft, the intermediate shaft, and the axle are arranged. The space for installation of the power transmission structure in the above is also small, so that there is room for installing other objects, and the working vehicle as a whole can be downsized, which is beneficial.

[0008]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 4 shows a lawn mower as an example of a working vehicle according to the present invention. This lawn mower is provided with a longitudinal body type engine 1 at a front part, a steering part 2 at a center part, and a body 3 having a power transmission device A fixed at a rear part, and a pair of front wheels 4.
And a rear wheel 5 so that the vehicle can run, and a mower 6 is suspended from the lower abdomen of the fuselage. Power transmission device A and mower 6
Means that the engine 1 is driven by the belt transmission mechanisms 7 and 8.
Is configured to be input.

As shown in FIGS. 1 and 2, the power transmission device A uses a power input portion 9 for inputting the power of the engine 1 by a belt transmission mechanism 7 and a taper cone 10 for continuously changing the input power. The friction type continuously variable transmission mechanism 11 includes a friction type continuously variable transmission mechanism 11, a forward / reverse switching mechanism 12 capable of switching the rotation direction of the output of the friction type continuously variable transmission mechanism 11, and a differential mechanism 13. The forward / reverse switching mechanism 12 and the differential mechanism 13 are housed in one case 14.

The power input unit 9 includes a longitudinal axis 16 having an input pulley 15 and an input rotating body 17 of the friction type continuously variable transmission mechanism 11.
Are linked by a bevel gear mechanism.

The friction-type continuously variable transmission mechanism 11 is provided around a main shaft 18 rotatably supported by a case 14.
A main shaft 18 is provided by an input rotating body 17 arranged concentrically with
A plurality of self-rotating taper cones 10 that revolve around the axis of the shaft are provided, and an output rotating body 19 that is driven and rotated in contact with the taper cones 10 is attached to the main shaft 18, and in contact with the tapered cones 10. The transmission member 20 is provided so as to be shiftable in the axial direction. The tapered cone 10 comes into pressure contact with the output rotary body 19 pressed and urged by the cam mechanism 21, receives the reaction force thereof by the disk-shaped cone support 22, and also has the outer frame 23 attached to the input rotary body 17.
And an inner frame 24 connected to the outer frame 23 to form a carrier 25, and the taper cone 10 is rotatably supported by a support shaft 26 provided between the outer frame 23 and the inner frame 24.

The forward / reverse switching mechanism 12 includes a main shaft 18 and an intermediate shaft 28 having a brake device 27 at one end. More specifically, a drive gear 29 of the main shaft 18 and a driven gear 30 of the intermediate shaft 28 are provided. The drive sprocket 31 of the main shaft 18 and the driven sprocket 3 of the intermediate shaft 28
The rotation of the intermediate shaft 28 can be selected by selectively connecting the driven gear 30 of the shift rotating tool 34 and the driven sprocket 32 with the chain 33 stretched between the two. doing.

The differential mechanism 13 fits the left and right axles 35, 35 inside the differential carrier 36, and the friction type continuously variable transmission mechanism 11 is located relative to the forward / reverse switching mechanism 12 on the intermediate shaft 28. Transmission gear 37 and differential carrier 3
6 and the passive gear 38 provided in the gear 6.

As shown in FIG. 3, the output shaft 18, the intermediate shaft 28, and the axles 35, 35 are arranged in parallel from the front along the same horizontal plane. And
As shown in FIGS. 1 and 2, the driving gear 29, the driven gear 30, the driving sprocket 31 and the driven sprocket 32 of the forward / reverse switching mechanism 12 are partially different from the friction type continuously variable transmission mechanism 11 in the axial direction of the main shaft 18. The driven gear 30 and the driven sprocket 32 of the forward / reverse switching mechanism 12 partially overlap the passive gear 38 of the differential mechanism 13 when viewed in the axial direction of the main shaft 18. It is arranged in.

With the above configuration, as shown in FIGS. 1 and 2, the friction type continuously variable transmission mechanism 11 and the differential mechanism 13 are coupled with the main shaft 18 with respect to the forward / reverse switching mechanism 12 in a state of being overlapped in the front-back direction. Since the same alligator is arranged in the axial direction,
The left and right widths of the case 14 are generally set to a width in which the frictionless continuously variable transmission mechanism 11 and the forward / reverse switching mechanism 12 can be arranged.

In the claims, reference numerals are provided for convenience of comparison with the drawings, but the present invention is not limited to the configuration shown in the attached drawings.

[Brief description of the drawings]

FIG. 1 is an expanded sectional view showing an input side structure of a power transmission structure.

FIG. 2 is an expanded sectional view showing an output side structure of the power transmission structure.

FIG. 3 is a side view showing a power transmission structure.

FIG. 4 is an overall side view showing the lawn mower.

FIG. 5 is an expanded sectional view showing an input side structure of a driven power transmission structure.

FIG. 6 is an expanded sectional view showing an output side structure of a driven power transmission structure.

[Explanation of symbols]

 Reference Signs List 10 Taper cone 11 Friction-type continuously variable transmission mechanism 12 Forward / reverse rotation switching mechanism 13 Differential mechanism 18 Main shaft 28 Intermediate shaft 35 Axle

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-2-300549 (JP, A) JP-A-62-297564 (JP, A) JP-A-61-99758 (JP, A) JP-A-60-1985 222657 (JP, A) Japanese Utility Model Showa 60-164160 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) F16H 37/02 F16H 15/52

Claims (1)

(57) [Claims] An input rotational power is supplied to a taper cone (1).
0), a continuously variable friction mechanism (1)
1) is equipped so as to be able to transmit the shifting power to the main shaft (18), and an intermediate shaft (28) arranged in parallel with the main shaft (18); the intermediate shaft (28) and the main shaft (18).
A forward / reverse switching mechanism (12) capable of transmitting power to the vehicle and switching the rotational power between forward and reverse rotations; and a differential mechanism (13) for an axle (35) provided in parallel with the main shaft (18); in the power transmission structure in the intermediate shaft (28) and a work vehicle that is able to transmit power associated, said friction
Type continuously variable transmission mechanism (11) and the forward / reverse switching mechanism (12)
Are disposed so as to face each other in the axial direction of the main shaft (18).
And the forward / reverse switching mechanism (12) and the differential mechanism
(13) is partially overlapped with the axial center direction
And the friction type continuously variable transmission mechanism (11)
And the differential mechanism (13) by the forward / reverse switching mechanism (1).
2) A power transmission structure for a working vehicle, wherein the power transmission structure is arranged on the same girder in the axial direction of the main shaft (18).