JPH0611007A - Transmitter for working vehicle - Google Patents

Abstract

PURPOSE:To provide a CVT suitable for a transmitter for a two-wheel drive type working vehicle without uselessness in a mechanism by setting a main shaft as an output shaft, and projecting both ends of the main shaft outward of a speed change case. CONSTITUTION:A speed change unit 1 is such constituted that a plurality of driving rotating elements 7, which are revolvingly driven on an axis of a main shaft 3, are disposed around the main shaft 3 and a speed change member 10 capable of shifting in the axial direction is brought into contact with the driving rotating elements 7. An input rotating member 20 for driving the driving rotating elements 7 is fitted around the main shaft 3 for free relative rotation, where both ends of the main shaft 3 extend outward of a speed change case C for covering the speed change unit 1 and power take-off units 12, 12 for driving a traveling device are provided at both the extended ends of the main shaft 3, respectively, thus constituting a CVT. Consequently, since the input portion is disposed at one portion and a pair of output portions are located symmetrically to the speed change case, the CVT becomes suitable for a transmitter for a two-wheel drive type working vehicle requiring a couple of right and left driving wheel bodies.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a friction type continuously variable transmission (Continuous Variable Trans).
The present invention relates to a transmission device using a miss (hereinafter abbreviated as CVT)], and more particularly to a technique for forming a suitable transmission device for a small work vehicle.

[0002]

2. Description of the Related Art In a CVT, a ring-shaped speed change member, such as a taper cone or a disk, which is brought into contact with a driving rotating body is axially shifted to change the radius of a contact point with the driving rotating body, thereby continuously shifting gears. However, there is an advantage that it can be made compact and continuously variable transmission can be output. for that reason,
As proposed in Japanese Patent Application No. 2-92166 previously filed by the present applicant, the adoption of a binder or the like in a small work vehicle has been planned.

[0003]

Therefore, it is also possible to use the CVT as a transmission device for a traveling device of a two-wheel drive type work vehicle having a pair of driving wheels such as a self-propelled walking type lawn mower and a management machine. Although considered, the structure disclosed in the above publication is based on the premise that a gear mechanism, a chain mechanism or the like is interposed between the CVT and the traveling device, and the C for the transmission structure is used.
If the VT is used as it is in a two-wheel drive work vehicle, the above gear mechanism, which is not an essential mechanism, is required, which causes waste in design, so it seems that there is room for improvement. To be An object of the present invention is to provide a CVT suitable for a transmission device of a two-wheel drive type work vehicle by restructuring the structure without waste of the mechanism.

[0004]

In order to achieve the above object, the present invention provides a plurality of drive rotating bodies which are revolved around a main shaft around an axis of the main shaft and which are driven. A speed change member that is shiftable in the axial direction is brought into contact with the rotating body to form a speed change unit, and an input rotating member for driving the drive rotating body is fitted to the main shaft so as to be relatively rotatable, and The CVT is characterized in that both ends are extended to the outside of the gear shift case that covers the gear shift portion, and a power take-out portion for driving the traveling device is provided at each of the extended both spindle ends to form a CVT. .

[0005]

According to the above characteristic construction, the CVT is constructed so that the input from the outside is transmitted to the input rotary member and the output is taken out from the main shaft, and the main shaft which is the output shaft is extended to the outside of the transmission case. Therefore, for example, a wheel-type work vehicle (walking lawn mower, etc.) is configured by directly attaching wheels to each of the two extending spindles, or to each of the two extending spindles via a gear reduction mechanism. It becomes easier to set things such as installing a sprocket to configure a crawler type work vehicle (management machine, etc.). That is, it is suitable for a transmission device for a two-wheel drive work vehicle that requires a pair of left and right driving wheels by providing one input portion and a pair of output portions at positions symmetrical with respect to the transmission case. It can take various forms.

[0006]

Therefore, in the CVT, by setting the main shaft as the output shaft and projecting both ends of the output shaft out of the case, a small two-wheel drive work such as a walk-type lawn mower, a management machine, or a small transport vehicle. It was possible to provide a CVT-based transmission suitable for a vehicle.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a transmission device suitable for an agricultural machine such as a walk-type cultivator. This transmission is composed of a CVT 30 and has a ball bearing 2 at both ends of a transmission case C composed of a left case Ca and a right case Cb.
A main shaft 3 which also functions as an output shaft is supported via 2, 4, and a carrier 5 integrally formed with a rotary input portion is supported by the main shaft 3 in a free-rotating manner. For the upper and lower holding portions 5a, 5a formed on the carrier 5, three taper cones 7 with which the support shafts 6 are engaged and supported are arranged, and a disk-shaped rotating body 8 that contacts the large diameter side of these taper cones 7 ,
Further, automatic pressure adjusting mechanisms A for adjusting the contact pressure between the rotating body 8 and the taper cone 7 are provided coaxially with the main shaft 3. A ring-shaped speed change member 10 and a taper cone 7 which are configured to be shiftable along a rod 9 installed in a speed change case C in a state of being parallel to the axis P of the main shaft 3 and which circumscribes each taper cone 7. A support member 11 is provided which has a protruding edge 11a in contact with an annular recess 7a formed on the small diameter side of each of the speed change portion 1 and the taper cone 7 and which is supported by the main shaft 3 in an idling manner. Both ends are extended to the outside of the transmission case C to form power take-out portions 12, 12. Further, in this CVT 30, ball bearings 2 and 2 are provided between the carrier base portion 5A serving as an input portion and the main shaft 3, a needle bearing 16 is provided between the support member 11 and the main shaft 3, and a thrust bearing 17 is provided. Support member 1
It is interposed between 1 and the collar 21. With the automatic pressure adjusting mechanism A including a transmission member 18 externally fitted to the main shaft 3 so as to be able to transmit torque, a rotating body 8 slidable along the axis P, and a ball 19 interposed therebetween. As the load increases, the rotating body 8 and the tapered cone 7 are pressed against each other more strongly. The carrier 5 is composed of a carrier base 5A and a carrier body 5B. That is, the carrier body 5B includes a plate-shaped support plate 13 made of sheet metal for the vertically penetrating protrusions 6A and 6B of the support shaft 6 that penetrates the tapered cone 7, and a support case 14 bolted to the support plate 13. Support plate 1
The carrier 5 is constructed by bolting 3 to the carrier base 5A. The support shaft 6 rotatably supports the tapered cone 7 by means of needle bearings 22, 22. And
In this CVT 30, in the state where power is input to the input pulley 20 attached to the carrier base 5A, when the shift member 10 is shifted by rotating the shift shaft 15, the shift member 10 comes into contact with the shift member 10. Since the radius of the taper cone 7 from the axis of rotation changes, that is, the circumferential length of the taper cone 7 changes at the position where the transmission member 10 contacts, the carrier 5
When is rotated by a unit amount, the rotation amount of the taper cone 7 that rotates following the inner surface of the speed change member 10 changes, and the rotation speed of the rotating body 8 to which power is transmitted from the taper cone 7 is the carrier 5 Therefore, the continuously variable power for traveling is transmitted to the left and right power take-out portions 12, 12 which are interlocked with a traveling device (not shown).

Next, an application example of the above-described transmission device will be briefly described. FIG. 2 shows a simplified traveling transmission device suitable for a self-propelled walking type lawn mower or the like, E is an engine, 23 is a belt transmission mechanism using the input pulley 20, and 25 is a power take-out unit 1.
It is a drive wheel attached to No. 2. FIG. 3 shows a transmission device suitable for a walk-behind lawn mower or the like, E is an engine, 23 is a belt transmission mechanism using the input pulley 20, and 24 is both power take-out parts 1.
2, 12 and the axles 26, 26 of the left and right rear wheels 25, 25. A steering clutch 27 is provided on each axle 26, 26, and each power take-off portion 12, 12
Each brake is equipped with a brake 28. FIG. 4 shows a transmission device suitable for a self-propelled cart (small transport vehicle) or the like, and includes a gear interlocking mechanism 24 and a sprocket 29 for a crawler traveling device.
Is substantially the same as the transmission shown in FIG.

It should be noted that reference numerals are given in the claims for convenience of comparison with the drawings, but the present invention is not limited to the configurations of the accompanying drawings by the entry.

[Brief description of drawings]

FIG. 1 is a developed sectional view showing the structure of a transmission device.

FIG. 2 is a system diagram of a transmission device showing a first application example of the transmission device.

FIG. 3 is a system diagram of a transmission device showing a second application example of the transmission device.

FIG. 4 is a system diagram of a transmission device showing a third application example of the transmission device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 gear shifting part 3 main shaft 7 drive rotating body 10 gear shifting member 12 power take-out portion 20 input rotation member C gear shifting case

Claims (1)

[Claims] 1. A plurality of drive rotating bodies (7) revolved around a main shaft (3) around an axis of the main shaft (3).
And a shift member (10) that is shiftable in the axial direction is brought into contact with the drive rotating body (7) to form a shift unit (1), and the drive rotating body (7) is driven. An input rotary member (20) for adjusting the rotation of the main shaft (3) is rotatably fitted onto the main shaft (3), and both ends of the main shaft (3) are outside the shift case (C) that covers the shift unit (1). A transmission device for a work vehicle, which is extended and is provided with power take-out portions (12), (12) for driving a traveling device at both extended end portions of the main shaft.