JP2553411Y2 - Tractor power transmission device - Google Patents

Description

[Detailed description of the invention]

[0001]

The present invention relates to a tractor transmission mechanism.
The present invention relates to an arrangement in which a reversing mechanism is provided in each of a traveling system and a PTO system.

[0002]

2. Description of the Related Art In a conventional tractor transmission mechanism, power is directly transmitted from an input shaft to an output shaft in the case of forward rotation, and a back gear shaft or the like is newly provided between the input shaft and the output shaft in the case of reverse rotation. The power was transmitted by providing an intermediate shaft and reversing it. In addition, when the intermediate shaft is not provided, a planetary gear system or an HST system is used.

[0003]

However, in the prior art, when a back gear shaft is provided as an intermediate shaft for reverse rotation in the prior art, the number of parts such as the back gear shaft, bearings, clips, etc. increases, and the number of assembly steps increases. Instead, it was necessary to secure a space for arranging them in the transmission case, and the addition of the reverse gear made the internal structure complicated and made the whole larger.
In addition, the number of shaft holes in the transmission case differs depending on the presence or absence of the reversing function, so there was a problem that the parts management became complicated. In addition, even in the case of the planetary gear system or the HST system, the entire transmission case became larger. -There was a problem that it was difficult to make it compact because of its complexity.

[0004]

The problems to be solved by the present invention are as described above. Next, means for solving the problems will be described. The traveling transmission mechanism and the power take-out transmission mechanism are
In a vertically structured tractor transmission mechanism,
Transmission shaft 3 constituting a speed mechanism, and a power take-out transmission
PTO transmission shaft 19 and PTO counter shaft 18 constituting the structure
Are arranged in parallel, and on the traveling transmission shaft 3
The power take-out gear 5c is arranged, and the power take-out gear 5c
The fixed gear 18a on the PTO counter shaft 18 always meshes
The fixed gear 18a is provided on the PTO counter shaft 18.
In addition, a plurality of fixed gears 18b.
.. Are a plurality of gears on the PTO transmission shaft 19.
Can be meshed by sliding the sliding gears 20a.
And a double reverse idler gear on the drive transmission shaft 3.
A) and one of the two reverse idler gears 22
Gear 22a is fixedly mounted on the PTO counter shaft 18.
The other gear 22b meshes with the gear 18b,
It is possible to mesh with the sliding gear 20a on the transmission shaft 19,
The idler gear for reverse rotation of the outgoing transmission
It is loosely fitted on the traveling transmission shaft 3 .

[0005]

The operation of the present invention will be described. Power from the engine E is transmitted from the input shaft 1 to the reverse counter gear 5b on the traveling transmission shaft 3 of the forward / reverse switching unit A. Power is transmitted from a power take-out gear 5c integrally provided to the reverse counter gear 5b to a fixed gear 18a on the PTO counter shaft 18 of the power take-out portion G. A fixed gear 18b, which is coaxial with the fixed gear 18a, meshes with a gear 22a of a double reverse idler gear 22 loosely fitted on the traveling transmission shaft 3, and another gear 22b slides on the PTO transmission shaft 19. Sliding the moving gear 20a enables meshing. By meshing the gear 22b with the sliding gear 20a, the PTO transmission shaft 1
From 9 the PTO shaft 21 can be rotated in the opposite direction.

[0006]

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 structure of a tractor power transmission device will be described. In the power transmission device of the tractor, a traveling transmission mechanism and a power take-off (PTO) transmission mechanism are configured independently. From the front, a main clutch 4, a forward / reverse switching unit A, a power take-out unit G, a main transmission unit B, an auxiliary transmission unit D, and a differential gear unit F are arranged. Front mission case 3
0, the input shaft 1, the traveling counter shaft 2, and the traveling transmission shaft 3 are supported by bearings and are horizontally supported in parallel, and the power of the engine E is supplied to the input shaft 1 via the main clutch 4. Conveyed to. The forward fixed gear 1 on the input shaft 1
Power is transmitted from a to a forward counter gear 5a loosely fitted to the traveling transmission shaft 3 via a fixed gear 2a on the traveling counter shaft 2. A reverse fixed gear 1b on the input shaft 1
Is engaged with the reverse counter gear 5b loosely fitted on the traveling transmission shaft 3 to transmit power.

The forward counter gear 5a and the reverse counter gear 5b are connected to a sliding gear 6 via a synchromesh gear.
By sliding a, meshing and interlocking connection are possible. The sliding gear 6a always meshes with a gear 6b fixed on the traveling transmission shaft 3, and the forward / backward switching is performed by operating the forward / backward switching lever (not shown) to slide the sliding gear 6a. is there.

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. Between the loose fitting gears 9a and 9b and the loose fitting gears 9c and 9d, there are sliding gears 10a and 1 respectively.
0b, the sliding gears 10a and 10b are operated by the operator in a main shifting operation so that the sliding gear 10a of the main transmission shaft 8 is either a loose fitting gear 9a or 9b, or the sliding gear 10b is a loose fitting gear. By sliding to either 9c or 9d, power is transmitted from the power transmission shaft 7 to the main transmission shaft 8 to enable four-step shifting.

Power is transmitted from the main transmission shaft 8 to a rear auxiliary transmission portion D, and further power can be transmitted to a creep transmission portion C. The auxiliary transmission portion D is fixed on the rear portion of the main transmission shaft 8. The gears 8a and 8b are formed, and the traveling drive shaft 12 is suspended in parallel with the main transmission shaft 8 and on an extension of the power transmission shaft 7. Further, the shaft 1 is parallel to the main transmission shaft 8.
4. The fixed gears 8a and 8b are engaged with the gears 13a or 13b by sliding a sliding gear 13 on the traveling drive shaft 12 to enable a high or low auxiliary shift. The fixed gear 8a further meshes with the gear 11a of the double loose fitting gear 11 on the shaft 14, while the other gear 11b is
The gear 16a of the upper two free-fitting gears 16 meshes with the other gear 16b, and the other gear 16b can mesh with the 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 is transmitted to a fixed gear 23a on the front wheel power take-out shaft 23 via a gear 24 loosely fitted to a PTO shaft 21 and a loosely fitted gear 25 described later. ,
The front wheel 26 is configured to be driven. The traveling drive shaft 12 transmits a bevel pinion 12b formed at the rear end to a differential gear device F, and drives the rear wheel 17 from the differential gear device F via a plurality of shafts and a reduction gear.

Next, the transmission of power to the PTO transmission mechanism will be described with reference to FIGS. The PTO transmission mechanism includes 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. Axis 1
9 are each supported by bearings and laid horizontally.
The reverse counter gear 5 loosely fitted to the traveling transmission shaft 3
b, a power take-out gear 5c is provided integrally,
The fixed gear 18a on the PTO counter shaft 18 meshes with the power take-out gear 5c so that power is always transmitted to the PTO system.

On the PTO counter shaft 18, in addition to the fixed gear 18a, fixed gears 18b, 18c, 18d, 18
The fixed gear 18c can be meshed by sliding a sliding gear 20a of the PTO transmission shaft 19, and the fixed gear 18d is a sliding gear 20b and the fixed gear 1
8e is a sliding gear 20c and sliding gears 20b and 20 respectively.
By sliding c, it is possible to engage, and a three-speed PTO shift of the forward rotation is possible. A reverse PTO speed change portion H is formed at the rear of the forward / reverse switching portion A, and two reverse idler gears 22 are loosely fitted on the traveling transmission shaft 3, and one of the two reverse idler gears 22 is engaged. The other gear 22a meshes with the fixed gear 18b.
In FIG. 3B, the sliding gear 20a on the PTO transmission shaft 19 is slidable so as to be meshable, and the reverse rotation is transmitted to the PTO transmission shaft 19. By sliding and engaging the sliding gears 20a, 20b, and 20c in this manner, the PTO speed is shifted from the input shaft 1 via the forward counter gear 5b, and power is transmitted to the PTO transmission shaft 19, and further, the PTO transmission shaft A PTO shaft 21 having a coaxial shaft core is connected to the rear end of the tractor 19, so that a working machine connected behind the tractor can be driven.

[0013]

[Effect of the Invention] The present invention is constructed as described above, and has the following effects. First, on the axis of the traveling system
Since the reverse gear was loosely fitted, the conventional transmission case was replaced.
It can be used as a reversal as it is
Parts management became easier. That is, in the prior art
In the tractor power transmission system,
It is rare that reverse rotation can be taken out by the system transmission mechanism
It was. Therefore, in a normal tractor, most
In many cases, it was impossible to take out the reverse rotation.
In such a power take-out speed change mechanism that only rotates forward,
And the reverse gear shaft as an intermediate shaft to reverse
If provided, the reverse gear shaft, bearings,
Fools who increase the number of parts such as loops and assembly man-hours
And place them inside the mission case
Space for the back gear.
In addition, the internal structure became complicated and the whole was enlarged.
Also, the number of shaft holes in the transmission case differs depending on the presence or absence of the reverse rotation function.
And the management of parts becomes complicated,
Yes, and even in the case of the planetary gear system or HST system,
Compact to make the entire case larger and more complex
There was a problem that the conversion was difficult. The present invention is
The reverse rotation can be added to the power take-out transmission mechanism like
The problem in the case of doing it was able to be solved. No.
Second, there is no need for an intermediate shaft such as a reverse gear shaft.
Process can be reduced and assembly is simple.
And make the entire transmission case compact
It became possible to do.

[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 unit G power take-out unit 3 traveling transmission shaft 18 PTO counter shaft 22a reverse idler gear

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-1-237225 (JP, A) JP-A-1-168523 (JP, A) JP-A-1-282027 (JP, A) 192924 (JP, U) Japanese Utility Model Showa 60-55533 (JP, U) Japanese Utility Model Showa 57-200756 (JP, U) Japanese Utility Model Utility Model 3-33256 (JP, U)

Claims (1)

(57) [Scope of request for utility model registration] 1. A transmission system transmission mechanism and a power take-out transmission mechanism.
In the transmission mechanism of the tractor independently configured,
Transmission drive shaft 3 that constitutes the transmission mechanism, and power take-out transmission
PTO transmission shaft 19 and PTO counter shaft 1 constituting the mechanism
8, the three shafts are arranged in parallel with each other on the traveling transmission shaft 3.
The power take-out gear 5c is arranged in the
And the fixed gear 18a on the PTO counter shaft 18 always mesh
The fixed gear 18 is provided on the PTO counter shaft 18.
a, a plurality of fixed gears 18b...
The fixed gears 18b...
Meshing possible by sliding two sliding gears 20a ...
And a double reverse idler on the drive transmission shaft 3.
The gear 22 is loosely fitted, and one of the two reverse
Gear 22 a is fixed on the PTO counter shaft 18.
And the other gear 22b is engaged with the PT
O transmission shaft 19 can be engaged with a sliding gear 20a,
Use the idler gear for reverse rotation of the take-out transmission
A power transmission device for a tractor, wherein the power transmission device is loosely fitted on the traveling transmission shaft 3 .