JPS6033093Y2 - A steering support structure for a tractor with a front wheel drive mechanism. - Google Patents

Description

[Detailed explanation of the invention] Generally, when the front wheels as steering wheels are used as the drive shaft,
There are problems in that the combination of the power transmission structure and the steering support structure not only results in a complex structure as a whole, but also increases in external size.

The present invention has been devised in view of this problem, and it is an object of the present invention to provide a steering support structure that is simple in structure and allows smooth steering operations.

The present invention will be explained below based on embodiments shown in the drawings.

Reference numeral 1 denotes a front wheel drive shaft of a tractor, which is supported within a shaft cover 2 by a bearing 3 and has a drive bevel gear 4 at its tip.

Reference numeral 5 denotes a front axle provided on a front wheel 6 serving as a steering wheel, which is supported 8 by a bearing on a bearing fitting 7, and has a large bevel gear 9 at its tip.

10 is a steering pivot shaft, the upper end of which is connected to the shaft cover 2.
The upper end of the upper outer cylinder 11 integrally connected to the bearing fitting 7 is pivotally supported 12 by a bearing, and the other lower end is pivotally supported 14 by a bearing to the lower end of the lower outer cylinder 13 integrally connected to the bearing fitting 7. ing.

Transmission bevel gears 15 are provided at the upper and lower parts of the same pivot shaft 10.
．． 16, and its upper bevel gear 15 is connected to the drive bevel gear 4.
By meshing the lower transmission bevel gear 16 with the large bevel gear 9, a front wheel drive mechanism is constructed that transmits power from the drive shaft 1 to the front axle 5 via the pivot shaft 10.

Reference numeral 17 denotes a support arm connected to the bearing fitting 7, and its tip is pivotally supported 18 by a bearing on the upper end of the upper outer cylinder 11 on the extension of the upper end of the pivot shaft 10.

19 is its short support shaft.

At a position above the virtual extension part 5' of the front axle 5 facing the pivot shaft 10, the lower end of the upper outer cylinder 11 supporting the pivot shaft 10 is formed into a downwardly extending part 1'. ' is inserted and protruded into the lower outer cylinder 13, and the lower outer cylinder 1
A seal 20 is fitted between the inner periphery of the upper end of 3 and the outer periphery of the extension part 11', and the lower outer cylinder 13 and the extension part 11 are connected through the seal 20.
' are rotatably connected in a sealed state.

A needle bearing 21 is fitted between the inner periphery of the lower end of the extending portion 11' and the pivot shaft 10, and the needle bearing 21 can reliably hold the axis of the pivot shaft 10.

That is, in the past, this needle bearing was fitted between the lower outer cylinder 13 and the upper end outer cylinder 11 similarly to the seal 20, and when this was done, the pivot shaft 10
The upper end support part 12 and the lower end shaft support part 14 are provided in the upper end outer cylinder 11 and the lower end outer cylinder 13 which are formed separately, and as shown in the drawing, the pivot shaft 10 extends slightly outward from the lower side. Since the outer cylinders 11 and 13 are erected and tilted in the direction, a bending force acts on the fitting connection portion of the outer cylinders 11 and 13 due to the weight of the vehicle body, and this refractive force causes the axis of the pivot shaft 10 to bend. The heart is the outer cylinder 1
However, in this case, as described above, the needle bearing 21 that directly supports the pivot shaft 10 is moved from the upper outer cylinder 11 to the upper outer cylinder 11. This positional shift can be prevented by fitting it between the pivot shaft 10 and the pivot shaft 10.

In addition, in the conventional model, as mentioned above, the needle bearing is fitted together with the seal between the lower outer cylinder 13 and the upper outer cylinder 11, so the length of the fitting connection is large, and this Accordingly, there is a problem in that the inner wall 13' of the lower outer cylinder 13 extends to the temporary extension part 6' of the front axle 5 facing the pivot shaft 10, and the front axle 5 must be moved back in the proximal direction by that amount. However, since the needle bearing 21 is provided between the upper outer cylinder 11 and the pivot shaft 10 as described above, it is no longer necessary to extend the inner wall 13' of the lower outer cylinder 13. Since the fitting connection portions of the outer cylinders 1 and 13 can be provided above the virtual extension 5' of the front axle 5, the front axle 5 can be moved forward toward the tip and the entire structure can be made compact. be.

The reference numeral 22 in the figure is a steering arm provided integrally with the support arm 17, and the reference numeral 23 is a drag rod connected to the tip of the arm 22.

Reference numeral 24 denotes an oil communication hole bored in the upper outer cylinder 13 between the seal 20 and the needle bearing 21 and at the virtual extension 5' position. Since the position is not easily affected by the centrifugal force generated as the bevel gear 9 rotates, oil can flow out smoothly from the communication hole 24, and the communication hole 2
Air is allowed to flow in through 4.

Reference numeral 25 indicates a rattling adjustment bolt during assembly.

In the support structure of the present invention, the lower outer cylinder 13 and the support arm 17 act as a knuckle joint, and the pivot shaft 10 acts as a kingpin while acting as a power transmission shaft. When the drag rod 23 is operated in conjunction with the motor (not shown), the bearing fitting 7 rotates around the pivot shaft 10 and the front wheels 6 are steered.

Since the present invention is configured as □′ as described above, the positioning of the pivot shaft is ensured, and the power transmission and function as a kingpin can be performed smoothly, and the front axle can be advanced toward the tip side. This has the effect that the front wheels can be placed close to each other and the entire support structure can be configured compactly.

″ □Moreover, there is an effect that oil can be smoothly and reliably supplied into the lower outer cylinder through the oil communication hole provided in the upper outer cylinder extension.

[Brief explanation of drawings]

The drawing is a sectional view showing the steering support structure according to the embodiment of the present invention. 1: Front wheel drive shaft, '2: Shaft cover, 5: Front axle, 5': Virtual extension, 7: Bearing fitting, 10: Steering pivot shaft, 11: Upper end outer cylinder, 12-: Shaft support, 13 : Lower outer cylinder, 14-axis support, 20: Seal, 1: Needle bearing.

Claims (1)

[Scope of utility model registration request] The upper end outer cylinder 11 of the steering pivot shaft 10 is connected to the shaft cover 2 of the front wheel drive shaft 1, and the lower outer cylinder 13 of the pivot shaft 10 is connected to the bearing fitting 7 of the front axle 5. The upper end of the pivot shaft 101 is supported 12 on the upper end of the upper outer cylinder 11, and the lower end of the pivot shaft 10 is supported 14 on the lower end of the lower outer cylinder 13 to receive power from the drive shaft 1. The pivot axis 10
an upper outer cylinder 11 that supports the pivot shaft 10 at a position above the virtual extension 5' of the front axle 5 toward the pivot shaft 10;
The lower end is extended downwardly as a part 1', and the extended part 1.1' is inserted and protruded into the inside of the lower outer cylinder 13, and the inner periphery of the upper end of the lower outer cylinder 13 is extended into the extended part 11. A needle bearing 21 is fitted between the inner periphery of the lower end of the extending portion 11' and the pivot shaft 10, and a needle bearing 21 is fitted between the inner periphery of the lower end of the extending portion 11' and the pivot shaft 10. A steering support structure for a tractor having a front wheel drive mechanism, characterized in that an oil communication hole 24 is formed at a 5' position of a virtual extension of the tractor.