JPS6012750Y2 - Tractor front power take-off - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to a front power take-off device for a tractor.

Conventionally, when an agricultural tractor carries out agricultural work such as plowing with a towing device such as a power tiller attached to the rear of the tractor, the front part of the tractor has been used to prevent the front part of the tractor from lifting up due to ground resistance. Front weights are provided.

On the other hand, some agricultural tractors are not only capable of attaching a working implement to the rear thereof, but also are capable of attaching a working implement to the front thereof.

In such a tractor, a working machine such as a tiller is attached to the front part of the tractor via a three-point link mechanism, and a power transmission device is provided for transmitting power from the engine to the working machine.

In this case, since the front portion of the tractor is narrow, a power transmission device is provided in place of the front weight.

However, since the power transmission device is relatively lightweight and is fixed to the front bumper, the power transmission device cannot fully function as a front weight during rear installation work, and a separate additional weight is required. Establishing a system also made the structure complicated and caused problems in agricultural operations.

Also, during front loading work, depending on the type of work equipment to be installed, the joint angle between the power receiving shaft on the work equipment side and the PTO shaft on the tractor side may be inappropriate due to the relationship with the three-point linkage mechanism. There are cases where you want to change the longitudinal position of the shaft.

However, in the past, since the power transmission device was fixedly attached to the front bumper, such longitudinal adjustment was impossible.

The present invention was devised in view of such conventional problems, and in rear mounting work, even if the power transmission device is relatively lightweight, the device is mounted so as to protrude as far forward as possible from the front bumper. The purpose of this device is to combine the functions of a front weight, thereby simplifying the structure and effectively preventing the front of the trough from lifting. The purpose of this is to protrude forward and attach the joint angle between the power receiving shaft of the working machine and the PTO shaft of the device to an appropriate value.

Therefore, the features of the present invention are that the work equipment is mounted on the front of the tractor body via a three-point linkage mechanism so as to be able to move up and down, and the power from the engine is transferred to the power provided at the front of the vehicle body via a transmission shaft. Power is transmitted to a transmission device and further transmitted from the power transmission device to the working machine via a universal joint shaft, the power transmission device having a casing containing a gear reduction mechanism therein, The transmission shaft is connected to the rear side, and the universal joint shaft is connected to the front side, and the casing is removably fixed to the front surface of the front bumper through a spacer so as to protrude forward, and the spacer is adjustable in length. In addition, the transmission shaft is also configured to be adjustable in length.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.The front part of the tractor body 1 includes a front axle bearing pedestal 2, and a pair of left and right front wheels 4 supported on the lower surface of the pedestal 2 via a front axle case 3. It consists of an engine 5 etc. attached to the rear of the front vehicle bearing stand 2,
The engine 5 has one end of a crankshaft 6 protruding forward, and a belt pulley 7 is attached to the engine 5.

The belt hung around the pulley 7 rotates a radiator fan (not shown).

A mounting frame 8 is provided on both sides of the front part of the tractor body 1, and a front three-point link mechanism 9 is provided at the front end of the mounting frame 8.
A working machine 10 such as a muzzle-mounted rotary tiller is connected to the three-point linkage mechanism 9.

The front three-point link mechanism 9 is composed of a top link 11 and a pair of left and right lower links 12.
can be freely raised and lowered by a lift cylinder 15 via a lift rod 13 and a lift arm 14.

Reference numeral 16 denotes a power transmission device, which is detachably installed at the front end of the front vehicle bearing pedestal 2 between the pair of left and right mounting frames 8, and the front end of this front vehicle bearing pedestal 2 is used as a front bumper 17 of the tractor.

The power transmission device 16 is provided with a casing 18 that can be freely divided into front and rear sections, an input shaft 19 and a front section °C shaft 20 that are mounted on the casing 18 in the longitudinal direction of the axis, and the input shaft 19 has a spur gear shape. A small diameter gear 21 is fitted with a spline,
A large-diameter gear 22 that meshes with the small-diameter gear 21 is spline-fitted onto the front PTO shaft 20 .

That is, the casing 18 includes a speed reduction mechanism.

The rear end of the input shaft 19 projects from the rear surface of the casing 18 and is connected to the pulley 7 via a flexible joint 23, a connecting shaft 24, and a torsion bar 25.

The torsion bar 25 and the connecting shaft 24 are spline-fitted so as to be slidable in the axial direction on the same axis, forming an axial adjustment section 26, which is connected to the torsion bar 25 with a set bolt 27 provided on the adjustment section 26. The shaft 24 is fixedly fitted.

Also, the rear end of the torsion bar 25 is connected to the pulley 7 by a connecting body 28.
are spline-fitted and fixed with set bolts 29.

In this case, the torsion bar 25 and the connecting shaft 24 may be integrally formed by spline fitting or cross-fitting.

The flexible joint 23 has flange members 3o provided at opposing ends of the input shaft 19 and the connecting shaft 24, respectively, and
One flange member 30 is provided with an insertion hole 31, an elastic cylinder 32 is fitted into the hole 31, and one end of a shaft 33 fitted into the inner hole of the cylinder 32 is connected to the other flange member 30.
It is fixed in a cantilevered manner.

On the other hand, a front portion P protruding forward from the front surface of the casing 18
The TO shaft 20 is connected to the power receiving shaft of the working machine 10 via the universal joint shaft 34, and the power transmission device 16 decelerates the power from the engine 5 mounted on the tractor to the working machine 10 and interlocks it. introduce.

There are mounting flanges 35 on the left and right sides of the rear end of the casing 18.
is provided protrudingly, and the mounting flange 35 and the front bumper 1
A cylindrical spacer 36 extending in the longitudinal direction of the axis is interposed between 7 and the mounting hole 3 penetrated by the mounting flange 35.
7 and the inner hole of the cylindrical spacer 36, and is screwed into the bolt hole 38 of the front bumper 17.
9 is provided, and the power transmission device 16 is connected to the front bumper 1.
7 and protrudes forward.

In addition, in the example shown in FIG. 2, the cylindrical spacer 36 has a circular cylindrical cross section and is divided in the axial direction, and the power transmission device 16 is separated from the front bumper 17 by the adjustment of each cylindrical spacer 36. It is said to be adjustable.

In this case, the cylindrical spacer 36 may have a polygonal cross section, or may have a U-shaped cross section that can be inserted into and removed from the mounting bolt 39 in the radial direction of the bolt 39, and the cylindrical spacer 36 may have a polygonal cross section. The shaped spacers 36 may be connected in the shape of a spigot.

Further, the bolt hole 38 may also be used as a hole for attaching a conventional front weight.

According to the above configuration, during front loading work, the rotational power from the crankshaft 6 is transmitted to the work machine via the power transmission device 16.
However, when an overload occurs on the working machine 10, damage to the engine 5, such as the crankshaft 6, is avoided due to twisting of the torsion bar 25.

Furthermore, even if the axes or distance between the crankshaft 6 and the input shaft 19 are slightly deviated, the flexible joint 23 and the adjustment section 26 can adjust the position of both shafts 6, 19.
It is advantageous that the power is transmitted smoothly by connecting the two.

Furthermore, since the casing 18 of the power transmission device 16 is protruded forward from the front bumper 17 so that the distance can be adjusted freely, it is possible to set the distance between the power receiving shafts of the zero commercial machine on the two PTO shafts to an appropriate value. Therefore, the joint angle of the universal joint shaft 34 can be made appropriate.

Furthermore, during rear installation work, since the casing 18 of the power transmission device 16 is protruded forward from the front bumper 17 so that the distance can be adjusted, the load supported by the front wheels 4 can be increased and adjusted. By applying an appropriate support load to the front wheels 4, lifting of the front part of the tractor can be effectively prevented, which is of practical benefit.

According to the present invention, even if the power transmission device 16 is relatively lightweight, it can perform the original function of transmitting power from the engine 5 to the working machine 10, while still providing a front part for preventing the front part of the tractor from lifting. This was a highly useful invention, as it was able to fully function as a weight, set the joint angle of the muzzleloader to an appropriate level, and simplify the structure of the tractor as a whole. It is.

[Brief explanation of the drawing]

The figures show an embodiment of the present invention; FIG. 1 is a cutaway side view of the front portion of the tractor, and FIG. 2 is an enlarged view of the main part of FIG. 1. DESCRIPTION OF SYMBOLS 1... Tractor body, 5... Engine, 9... Three-point link mechanism, 10... Work equipment, 16... Power transmission Fitted fl, 17...
...Front bumper 18...Casing,
20...PTO shaft, 36...Spacer.

Claims (1)

[Scope of Claim for Utility Model Registration] A work implement is attached to the front of the tractor body via a three-point linkage mechanism so as to be able to move up and down, and power from the engine is transmitted via a transmission shaft to a power transmission device provided at the front of the vehicle body. and further transmits power from the power transmission device to the working machine via a universal joint shaft, the power transmission device having a casing that houses a gear reduction mechanism, and a rear surface side of the casing. The transmission shaft is connected to the front side of the transmission shaft, and the universal joint shaft is connected to the front side of the casing, and the casing is removably fixed to the front surface of the front bumper in a forwardly projecting manner through a spacer, and the spacer is configured to be freely adjustable in length. A front power take-off device for a tractor, characterized in that the transmission shaft is also configured to be adjustable in length.