JPS6348402Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a front axle extension device for a front wheel drive tractor.

The axle length of agricultural and civil engineering tractors must be lengthened or shortened depending on driving stability and work conditions.

Since the rear axle protrudes from the vehicle body, it is easier to extend the axle compared to the front axle, but since the front axle is swingably suspended from the vehicle body, it is difficult to extend the axle. Accompany.

In particular, when the structure is such that the front wheels are driven, the above-mentioned difficulty becomes acute.

Conventionally, there have been front axle extension devices for front wheel drive types in which the front axle has a so-called nested structure and is expanded and contracted by a fluid cylinder, or extended by a rack pinion, but both methods have the problem of being structurally complex and expensive. Yes, but the extension time was extremely troublesome.

Therefore, the present invention uses a so-called assembly having an intermediate shaft in a cylindrical space, forms a pilot fitting part in the cylindrical spacer of the assembly, and inserts and removes the spacer to connect the front axle. Therefore, in this invention, a transmission case is attached to the outer end of the cylindrical front axle, and the transmission shaft inserted and supported inside the front axle is attached to the transmission case. In a front wheel drive tractor that can be freely linked to the front wheels via a transmission mechanism inside, a spigot fitting part is formed at the mounting joint between the front axle and the transmission case, and the front axle and the front axle are connected to each other through the spigot fitting part. The transmission case can be connected and separated, and the transmission shaft and the input shaft of the transmission mechanism can be connected and separated via a cylindrical joint that can be inserted and removed in the axial direction, and the pilot fitting is fitted on both ends in the axial direction. A cylindrical spacer having a removable spigot fitting portion formed therein is removably fixed between the front axle and the transmission case, and an intermediate shaft that interlocks and connects the transmission shaft and the input shaft is cylindrical. It is characterized by being provided within the spacer via a bearing.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

1 and 2 show a front wheel drive tractor 1,
It has a pair of left and right front wheels 2 and a pair of left and right rear wheels 3.

4 is an engine, and the power is provided by the transmission case 5.
It can be freely interlocked with the rear wheel 3 via an appropriate transmission mechanism.

Reference numeral 6 denotes a front wheel propulsion shaft device, which is driven in synchronization or synchronization with the rear wheel transmission mechanism inside the transmission case 5, and is provided at the lower bottom of the vehicle body in the longitudinal direction.

Reference numeral 7 designates a front axle, the center portion of which is swingably suspended via a center pin 8, and a differential mechanism to which the input shaft of the front wheel propulsion shaft device 6 is interlocked is built in the central case portion 9. ing.

The front axle 7 has a cylindrical shape made of cast metal, drawn or extruded steel pipe, sheet metal, or the like, and a pair of left and right transmission shafts 10, which are differential output shafts, are rotatably inserted therein.

Reference numeral 11 denotes a transmission case, which houses a transmission mechanism 12 represented by a bevel gear mechanism, through which the front wheels 2 can be driven.

Note that the vertical axis of the transmission mechanism 12 serves as a so-called kingpin, which enables the front wheels 2 to be steered.

As shown in FIG. 3, a flange 13 is attached to the outer end of the front axle 7 (both ends, but only one is shown in the figure).
is fixed, and the flange 13 is formed with a female-type spigot fitting part 14 in this example, and further formed with a plurality of knock pin holes 15 and bolt insertion holes 16.

In this example, the transmission case 11 includes a bearing case 2 in which the input shaft 17 of the transmission mechanism 12 is supported by bearings 18 and 19.
0 is attached by a dowel pin 21 and a bolt 22, and in this example, a male pilot fitting part 23 is formed in the bearing case 20, and the pilot fitting part 23 is male and female fitted into the pilot fitting part 14. It has a shape that

Therefore, when the shaft length is the standard shown in FIG. 1, the spigot fitting part 14 of the front axle 7 and the spigot fitting part 23 on the transmission case 11 side are male-female fitted, and the knock pin,
Attach the transmission case 11 to the front axle 7 with bolts, etc., and attach the spline portion 17A of the input shaft 17.
and the spline portion 10A of the transmission shaft 10 are joined via a cylindrical joint 24 that can be freely inserted and removed in the axial direction.

25 is a cylindrical spacer, and the front axle 7 is attached to the main body 25A and flanges 26 and 27 at both ends in the axial direction.
A spigot fitting part 28, which is a male type that can be freely fitted into and removed from the spigot fitting part 14, and a spigot fitting part 29, which is a female type that can be freely fitted and removed, are formed on the spigot fitting part 23 on the side of the transmission case 11, respectively. At the same time, an intermediate shaft 31 is inserted into one flange 26 on the cylinder axis via a bearing 30, and spline portions 31A are formed at both ends of the intermediate shaft 31, respectively.

Furthermore, the flanges 26 and 27 have knock pin holes 3.
2 and the bolt insertion hole 33 are the holes 15 and 16 described above.
and an O-ring 34 is attached to the outer periphery of the fitting portion.

3, one spacer 25 is used above the center line XX in the drawing, and two spacers 25 are used below the center line XX to connect the bolt 22 and the knock pin 2.
1, 35, a cylindrical joint 24 in which a cylindrical spacer 25 is interposed between the front axle 7 and the transmission case 11 using bolts 36, and the transmission shaft 10 and the input shaft 12 can be freely inserted and removed in the axial direction via the intermediate shaft 31; , 37 are interlocked and connected.

In addition, the spigot fitting parts 14, 23, 28, 29
Male and female may be reversed from those shown. Also, the fifth
6 shows a steering mechanism for the front wheels 2, in which a pitman arm 38 is pivotally mounted at a location offset by a symbol L from the vehicle center line Y-Y.
8 and left and right knuckle arms 39, 40 are interlocked by tie rods 41, 42 of telescopic structure.

In this case, since the Pitman arm 38 is unevenly distributed by L, in order to avoid a difference in the turning angles θ ₁ and θ ₂ of the left and right front wheels 2, the pivot fulcrum 38A of the Pitman arm 38 and the tie rod are attached as shown in FIG. The lengths L1 and L2 of the holes 38B and 38C are made different, and the left and right cutting angles θ ₁ and θ ₂ are corrected to be the same angle.

In short, in the present invention, the transmission case 11 is attached to the outer end of the cylindrical front axle 7, and the transmission shaft 10 inserted and supported in the front axle 7 is connected to the front wheel through the transmission mechanism 12 inside the transmission case 11. In the front wheel drive tractor 1 which can be freely interlocked with the front axle 7 and the transmission case 11, a spigot fitting part 14, 2 is provided at the attachment joint between the front axle 7 and the transmission case 11.
3 are formed respectively, and the spigot fitting part 14,
23, the front axle 7 and the transmission case 11 can be connected and separated, and the transmission shaft 10 and the input shaft 17 of the transmission mechanism 12 can be connected and separated through the cylindrical joint 24, which can be freely inserted and removed in the axial direction. Further, a cylindrical spacer 25 having pilot fitting portions 28 and 29 formed at both ends in the axial direction that can be freely fitted and removable into the pilot fitting portions 14 and 23 is detachably fixed between the front axle 7 and the transmission case 11. The transmission shaft 1 is freely provided.
0 and the input shaft 17 is provided in the cylindrical spacer 25 via a bearing 30, which has the following advantages.

When extending the axial length of the front axle 7, a cylindrical spacer 25 having an intermediate shaft 31 inserted through a bearing 30 is inserted between the transmission case 11 and the front axle 7 at the pilot fitting portions 14, 23, This can be carried out by fitting and supporting the cylindrical spacer 25 through 28 and 29.
Depending on the number of pieces, the shaft length can be made in various sizes.

Since the intermediate shaft 31 is inserted into the cylindrical spacer 25, the transmission shaft 10 and the input shaft 17 can be easily joined when extending the axle.

In addition, since the fitting is done by the pilot fitting parts 14, 23, 28, 29, the connection is accurate and there is no misalignment, which not only allows the front wheel 2 to be driven accurately, but also prevents loosening of the bolts 22, 36. can also be prevented.

Therefore, whether the front axle is extended alone or together with the rear axle, the shaft length can be easily changed, which is very beneficial, even though the vehicle is a front-wheel drive type.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; Fig. 1 is a front view of the tractor, Fig. 2 is a side view of the tractor, Fig. 3 is a planar sectional view showing two examples of extensions of the main part of the embodiment of the invention, FIG. 4 is a sectional view of an assembly including a cylindrical spacer, FIG. 5 is an explanatory view of the front wheel steering mechanism, and FIG. 6 is an enlarged view of the pitman arm. 1...Tractor, 2...Front wheel, 7...Front axle,
11...Transmission case, 12...Transmission mechanism, 10...
...Transmission shaft, 14, 23, 28, 29... Pilot fitting part, 17... Input shaft, 25... Cylindrical spacer, 30... Bearing, 31... Intermediate shaft, 24, 37
......Cylindrical joint.

Claims (1)

[Scope of utility model registration request] A transmission case 11 is attached to the outer end of the cylindrical front axle 7, and the transmission shaft 10 inserted and supported in the front axle 7 is connected to the front wheels 2 via a transmission mechanism 12 inside the transmission case 11.
In the front wheel drive tractor 1, which can be freely interlocked, pilot fitting parts 14 and 23 are formed at the mounting joint between the front axle 7 and the transmission case 11, respectively.
A cylindrical joint 24 allows the front axle 7 and the transmission case 11 to be freely joined and separated through the pilot fitting parts 14 and 23, and the transmission shaft 10 and the input shaft 17 of the transmission mechanism 12 can be freely inserted into and removed from each other in the axial direction. A cylindrical spacer 25 that can be joined and separated through the cylindrical spacer 25 and further has pilot fitting portions 28 and 29 formed on both axial end sides thereof to be able to be fitted and removed from the pilot fitting portions 14 and 23, respectively.
is detachably provided between the front axle 7 and the transmission case 11, and an intermediate shaft 31 that interlocks and connects the transmission shaft 10 and the input shaft 17 is provided within the cylindrical spacer 25 via a bearing 30. A front axle extension device for a front wheel drive tractor, characterized by: