JPS6329613Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a front wheel support device for a tractor.

Conventionally, a front wheel support device for a tractor includes a fixed case that is provided at both ends of the front axle case and pivotally supports the kingpin in the vertical direction, a transmission case that has an outwardly bulging portion that pivotally supports the front axle, and a transmission case that has an outwardly bulging portion that pivotally supports the front axle, and The transmission case and the kingpin support are vertically clamped by a kingpin support extending inwardly from the upper part of the side bulge, and the transmission case and the kingpin support are configured to be rotatable relative to the fixed case around the kingpin. be.

Therefore, in such a front wheel support device, since the kingpin support is attached in the lateral direction, the rigidity in the longitudinal direction is weak, and the space between the front wheels attached to both front axles is wide. was. Generally, the front wheels of a tractor are
Because the diameter is smaller than that of the rear wheels, the above-mentioned drawback of weaker rigidity in the front-rear direction has been exposed, especially when it comes to overcoming obstacles when moving forward or backward.

To improve this, a model with a king pin support installed in the front and back direction was published in 1976-50976.
However, in this case, the vertical part is located at the rear of the gear case, so it is a separate member from the steering arm, etc., which must be located at the rear due to the structure, and the tie rod is a separate member. Such a pivot structure also inevitably becomes cramped.

Therefore, this invention attempts to eliminate these drawbacks by constructing the king pin support in the front-rear direction and by making the shape, structure, etc. of the king pin support specific.

Hereinafter, embodiments of this invention will be described with reference to the drawings.

The tractor body 1 includes, from the front to the rear, a bonnet 2, a steering wheel 3, a passenger seat 4, a working machine C,
The vehicle has a conventional structure in which a lifting device 5 and the like are arranged, and front wheels 6 supported by a front wheel support device A and rear wheels 7 supported by a rear wheel support device B are arranged on the lower front and rear sides of the vehicle body 1.

By the way, the front wheel support device A according to this invention is
A fixed case 21 that pivotally supports a king pin 9 in the vertical direction is fixed to both ends of a front axle case 8 installed at the bottom of the fuselage 1 between the front wheels 6 on both sides. The transmission cases 10, 11 are vertically clamped by the transmission cases 10, 11 connected to the transmission cases 10, 11, and the king pin support 20 extending in the front-rear direction from the front of the transmission cases 10, 11.
The king pin support 20 is configured to be rotatable with respect to the fixed case 21 around the king pin 9.

The transmission cases 10 and 11 include an inner transmission case 10 that is fitted to the lower part of the fixed case 21 so as to be rotatable around the king pin 9, and one end of the inner side of the inner transmission case 10 that is rotatably fitted to the lower part of the outer side of the inner transmission case 10. External transmission case 1 installed so that it can be moved in the opposite direction such as upside down
1, a front wheel 12 is made to protrude outward from the other end portion of the external transmission case 11, and a front wheel 6 is attached to this protrusion. The inner transmission case 10 and the outer transmission case 11 are configured to be attached and detached using fasteners 13 such as bolts. Therefore, in order to enable the external transmission case 11 not only to rotate but also to be turned upside down, etc., the mounting positions of the fasteners 13 may be made vertically symmetrical.

In order to drive the front wheels 6, a differential device 14 is installed in the central enlarged part of the front axle case 8.
, take out the axle shaft 15 up to the fixed cases 21 on both sides, and connect the axle shaft 15 between each end and the upper part of the king pin 9, and between the lower part of the king pin 9 and the center of attachment of the inner transmission case 10 and the outer transmission case 11. A pair of bevel gears 17 and 17', and 18 and 18' respectively installed between the rotating shaft 16 mounted in a core shape are engaged with each other, and the rotating shaft 16 in the external transmission case 11 is
Gears 19, 19' attached to the front axle 12 and the front axle 12 are always in mesh with each other. As a result, the power of the engine (not shown) housed in the bonnet 2 is input to the differential gear 14 after being appropriately decelerated.
After this power is taken out from the axle shaft 15, it is transferred to the king pin 9 by bevel gears 17, 17'.
In addition, the rotating shaft 1 is
6, and is transmitted from the front axle 12 to the front wheels 6 via the constantly meshing gears 19, 19' to drive them.

The king pin support 20 is formed into an inverted L shape when viewed from the side, such as an L-shaped cross section, and one end thereof is rotatably fitted into a protrusion of the king pin 9 protruding from the fixed case 21. let me,
The other end is attached directly to the front proper portion of the inner transmission case 10 or to the protrusion 22 thereof. As a result, when viewed from the side, the king pin support 20, the inner transmission case 10, and the fixed case 21 form a closed shape, and especially when the protruding portion 22 is added, a box shape as in this embodiment is formed.

Further, the king pin support 20 is integrally formed with an arm portion 20a having a steering function and having an L-shape in plan view, and one end of which is connected to the drag rod 2.
3, the other end is pivotally supported by a tie rod 24, and when the other end of this tie rod 24 is attached to an arm portion 20b provided on the other king pin support 20 and the operating handle 3 is operated, the , it becomes possible to steer the front wheels 6 on both sides.

The rear wheel support device B for the rear wheels 7 is an axle shaft 26 for the rear wheels taken out on both sides from a differential device (not shown) in the rear case 25 at the lower rear of the fuselage 1.
The front end of the transmission case 27 is attached rotatably around the rear end, and the rear wheel 7 is mounted on the rear end, and the engine power is transmitted from the axle shaft 26 within the transmission case 27 to the rear wheel. 7, and an appropriate number of arcuate long holes 28 centered on the axle shaft 26 are formed at appropriate locations in the transmission case 27.
Insert the fixing bolt 29 into this elongated hole 28 and tighten it to the rear case 25 to create a structure that can fix the transmission case 27, then loosen the fixing bolt 29,
A structure is used in which the height of the rear wheels 7 is determined and the height of the vehicle can be changed by re-tightening.

As is clear from the above description, this invention has changed the conventional installation of the kingpin support 20 in the side direction in the front wheel support device of a tractor.
Since the installation is changed to the front-rear direction, the king pin support 20, the fixed case 21, and the transmission cases 10, 11 have a closed shape when viewed from the side, the section modulus increases, and the rigidity in the front-rear direction can be increased. In addition, an inverted L-shaped king pin support 2
By arranging the vertical part of 0 in front of the fixed case 10, the vertical part will be located on the narrow side of the allowable space due to the toe-in of the front wheel. The pivot side of the tie rod 24 is located on the wider side, and the distance from the upper bearing of the kingpin 9, that is, the length of the arm, can be increased (needs to be longer than the vertical portion for strength reasons). The swing angle, that is, the steering angle can be increased within a range that does not interfere with the front wheels 6.
Furthermore, the pivoting structure with the tie rod 24 can be installed with sufficient margin. Also, Kingpin Support 20
By arranging the vertical portion toward the front, it also serves as a protective cover to prevent obstacles such as stones coming from the front as the tractor advances from colliding with the transmission case 21 and the fixed case 10.

In addition, the distance from the front axle case 8 to the front wheel 6 attached to the front axle 12 of the transmission cases 10, 11 can be shortened, making it possible to narrow the vehicle width; Since the bending moment applied to the front axle 12 etc. that supports the front wheels 6 can be reduced, the front axle etc. can be made thinner, and the tractor as a whole can be made more compact.

[Brief explanation of drawings]

FIG. 1 is a side view showing a tractor implementing this invention, FIG. 2 is a front view of the same, and FIG. 3 is a sectional view of a main part. Code, 1...Airframe, 6...Front wheel, 7...Rear wheel, 8...Front axle case, 9...King pin, 10,
11...Transmission case (10...Inner transmission case, 11...
external transmission case), 12...Front axle, 20...King pin support, 21...Fixed case.

Claims (1)

[Scope of utility model registration request] A transmission case 10 that supports the front wheel 6 is fixed to a fixed case 21 connected to the front axle case 8 so as to be rotatable in a substantially horizontal plane, and these fixed cases 2
1 and a kingpin 9 is mounted inside a transmission case 10, and the upper bearing of the kingpin 9 and the transmission case 10 are connected by a kingpin support 20 installed in the front-rear direction. is formed into an upside-down L-shape when viewed from the side, its vertical portion is positioned forward of the fixed case 21, the approximately center of the horizontal portion is fitted into the upper bearing of the king pin 20, and a tie rod is provided at the rear. A front wheel support device for a tractor, characterized in that a front wheel support device for a tractor is pivotally mounted.