JP2543037Y2 - Tractor power transmission device - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tractor transmission system having a traveling system and a PTO system, and to a technique for compactly storing them.

[0002]

2. Description of the Related Art Conventionally, the technology of an agricultural tractor in which a traveling transmission mechanism is provided at a front portion in a transmission case and a power take-off (PTO) transmission mechanism is provided at a rear portion has been known. And within the mission case,
Power from the engine is interrupted by a main clutch arranged in front of the traveling system transmission mechanism, and power from the main clutch passes through a traveling system transmission mechanism located between the main clutch and the PTO transmission mechanism. The transmission connection was made via the long PTO intermediate transmission shaft provided.

[0003]

However, in the prior art, the main clutch and the PTO at the rear of the transmission case have been disclosed.
Although the system transmission mechanism was connected by a long PTO intermediate transmission shaft, the long PTO intermediate transmission shaft is difficult to manufacture and increases the weight, leading to an increase in the weight of the entire agricultural tractor, and When the long PTO intermediate transmission shaft was rotated by the rotation of the engine, noise and vibration due to resonance tended to occur.

[0004] Further, since the PTO transmission mechanism is provided at the rearmost part of the agricultural tractor, the weight of the rear part of the vehicle is increased and the overall weight balance is deteriorated.
Because the power was obtained from the intermediate transmission shaft, the rotation speed was high and a reduction gear was required to obtain the required rotation speed in addition to the transmission mechanism, or a gear combination with a large reduction ratio was required.
There was a problem that the transmission case became large and the weight increased.

[0005]

The problems to be solved by the present invention are as described above. Next, means for solving the problems will be described. In other words, in a tractor having a forward / reverse switching device in addition to the traveling system transmission mechanism and a power take-off transmission system, the power extraction is performed to one of the forward / reverse counter gears of the forward / reverse switching section. Gears are provided integrally.

[0006]

The operation of the present invention will be described. The power from the engine E is transmitted to the input shaft 1 via the main clutch 4, and the forward counter gear 5 a loosely fitted to the traveling transmission shaft 3 of the forward / reverse switching unit A from the gear on the input shaft 1 and the reverse travel The power is transmitted to the counter gear 5b, and the power is taken out of the power take-out gear 5c integrally formed with the reverse counter gear 5b.
The power is transmitted to the fixed gear 18a on the O counter shaft 18, the power is transmitted from the gear on the PTO counter shaft 18 to the PTO shaft 21 via the sliding gear, and the work is connected to the rear part of the tractor. The machine can be driven.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The problems to be solved and means to be solved of the present invention are as described above. Next, the specific structure of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a side sectional view of a tractor power transmission device of the present invention, FIG. 2 is a side sectional view of a forward / reverse switching unit and a power take-out system, and FIG. 3 is a skeleton diagram of FIG.

Referring to FIGS. 1 and 3, the construction of the tractor power transmission device will be described. The power transmission device of the tractor includes a traveling system transmission mechanism and a PTO system transmission mechanism that are independent of each other. The main clutch 4, the forward / reverse switching unit A, the power take-out unit G, the main transmission unit B, and the subtransmission The input shaft 1, the traveling counter shaft 2, and the traveling transmission shaft 3 are respectively supported by bearings in the front transmission case 30, and are horizontally laid in parallel with each other. Engine E
Is transmitted to the input shaft 1 via the main clutch 4. Power is transmitted from the forward fixed gear 1a on the input shaft 1 to the forward counter gear 5a loosely fitted to the traveling transmission shaft 3 via the fixed gear 2a on the traveling counter shaft 2. Also,
The reverse fixed gear 1b on the input shaft 1 is meshed with a reverse counter gear 5b loosely fitted on the traveling transmission shaft 3 to transmit power.

The reverse counter gear 5a and the forward counter gear 5b are connected to a sliding gear 6 via a synchromesh gear.
The sliding gear 6a is always meshed with a gear 6b fixed on the traveling transmission shaft 3, and is operated by operating a forward / reverse switching lever (not shown). Slides to switch between forward and backward.

The power transmitted to the gear 6b is transmitted to a power transmission shaft 7 extending coaxially with the traveling transmission shaft 3, and fixed power gears 7a, 7b,. 7c ・
7d, and the power transmission shaft 7
The free-fitting gear 9a that is loosely fitted to the main transmission shaft 8 that is horizontally mounted in parallel with
9b, 9c, 9d are the fixed gears 7a, 7b, 7c, 7
d and the loose fitting gears 9a and 9b and the loose fitting gear 9c
Sliding gears 10a and 10b are disposed between the sliding gears 9a and 9d, respectively.
b or the sliding gear 10b is a loose fitting gear 9c.
9d, the power is transmitted from the power transmission shaft 7 to the main transmission shaft 8 to enable four-stage gear shifting.

Power is transmitted from the main transmission shaft 8 to the auxiliary transmission portion D, and further to the creep transmission portion C. The auxiliary transmission portion D is fixedly mounted on the rear portion of the main transmission shaft 8. 8a and 8b are formed, the traveling drive shaft 12 is laid horizontally on the power transmission shaft 7 in parallel with the main transmission shaft 8, and the shafts 14 and 15 are laid horizontally in parallel with the main transmission shaft 8. The fixed gears 8a and 8b are moved by sliding a sliding gear 13 on a traveling drive shaft 12 to form gears 13a and 13b.
And the high and low sub-shifts are enabled by the fixed gear 8a.
Further meshes with the gear 11a of the two free-fitting gears 11 on the shaft 14, and the other gear 11b
6, and the other gear 16b can mesh with a sliding gear 13a on the traveling drive shaft 12 to enable creep shifting. A fixed gear 12c is provided on the traveling drive shaft 12, and a front wheel power take-out shaft 23 is provided via a gear 24 loosely fitted to a PTO shaft 21 described later and a loosely fitted gear 25.
The transmission is transmitted to the upper fixed gear 23a to drive the front wheel 26, transmitted from the traveling drive shaft 12 to the differential gear device F from the rear end bevel pinion 12b, and transmitted from the differential gear device F to a plurality of shafts. The rear wheels 17 are driven via a reduction gear.

Next, the transmission of power to the PTO transmission mechanism will be described with reference to FIGS. The PTO transmission mechanism comprises a power take-out portion G and a reverse PTO speed-change portion H. The power take-out portion G is parallel to the traveling transmission shaft 3 of the forward / reverse switching portion A and has a PTO counter shaft 18 and a PTO transmission shaft. 19
The power take-out gear 5c, which is provided integrally with the reverse counter gear 5b loosely fitted to the traveling transmission shaft 3, is fixedly mounted on the PTO counter shaft 18. 18a so as to constantly transmit power to the PTO system.

On the PTO counter shaft 18, in addition to the fixed gear 18a, fixed gears 18b, 18c, 18d, 18e
The fixed gear 18c is connected to the PTO transmission shaft 1
9 can be meshed by sliding the sliding gear 20a, and the fixed gear 18d is
e is the sliding gear 20c and the sliding gears 20b and 20c, respectively.
The fixed gear 18b is a gear 22a of a double reverse PTO gear that is loosely fitted to the traveling transmission shaft 3 by sliding the gears. The other gear 22b can be meshed by sliding the sliding gear 20a on the PTO transmission shaft 19, and the reverse rotation is transmitted to the PTO transmission shaft 19 by this meshing. Further, a PTO shaft 21 having a coaxial axis is connected to the rear end of the PTO transmission shaft 19, so that a working machine connected behind the tractor can be driven.

[0014]

[Effect of the Invention] The present invention is constructed as described above, and has the following effects. First, since the gear of the traveling transmission mechanism and the reduction gear of the PTO transmission mechanism are also used, there is no need to provide a reduction gear, and the number of gears can be reduced to reduce gear noise. Since the combination of gears having a large reduction ratio is also eliminated, the entire tractor transmission case can be made compact.

Second, since the transmission portion of the PTO transmission mechanism can be disposed forward, the weight of the entire transmission case of the tractor is well balanced, and a long power transmission shaft is not required. As a result, generation of noise due to the noise is eliminated, and processing in the manufacturing process can be easily performed.

[Brief description of the drawings]

FIG. 1 is a side sectional view of a power transmission device for a tractor according to the present invention.

FIG. 2 is a side sectional view of a forward / reverse switching unit and a power take-out system.

FIG. 3 is a skeleton diagram of FIG. 1;

[Explanation of symbols]

 A forward / reverse switching part G power take-out part 3 traveling transmission shaft 5a forward counter gear 5b reverse counter gear 5c power take-out gear 18 PTO counter shaft 18a fixed gear

Claims (1)

(57) [Scope of request for utility model registration] In a tractor having a traveling system transmission mechanism and a power take-out system transmission mechanism independently, and having a forward / reverse switching device in addition to the traveling system transmission mechanism, a counter gear for either forward or backward of a forward / reverse switching unit is provided. A power transmission device for a tractor, wherein a power take-out gear is integrally provided on the tractor.