JPS6347573Y2 - - Google Patents

Description

[Detailed Description of the Invention] Technical Field of the Invention This invention relates to a rotating arm device for rotating front wheels in a steering direction in a front wheel drive device.

Technical background of the invention and its problems Conventionally, there have been various types of front wheel drive devices, one of the representative ones being a differential shaft whose inner end is connected to a differential device and extends horizontally, and a differential shaft whose inner end is connected to a differential device and which extends horizontally. A wheel shaft with a front wheel connected to the end thereof is arranged at different levels, and the outer end of the differential shaft and the inner end of the wheel shaft are connected via an idle shaft having a substantially vertical axis, a bevel gear, etc. exists. In this front wheel drive device,
A fixed case that holds the idle shaft rotatably around its axis is fixedly connected to the outer end of the shaft case that houses the differential shaft, and further surrounds the fixed case so that the wheel shaft can freely rotate around its axis. A rotating case for holding the idler shaft is rotatably connected to the idler shaft around its axis.
The rotating case holds an arm body, a part of which is located on the side of the fixed case on the front wheel side, and which is rotatable around the axis of the idle shaft.
The arm body is fixedly connected to the rotation case and also connected to the steering section.

Thus, the arm body has a side surface on the front wheel side and a side surface on the fixed case side that are both linear, and the left and right width is constant throughout. For this reason, if the arm body is made of a thick material to increase its strength, the wheel shaft will be lengthened accordingly, the amount of offset of the front wheels will increase, and turning performance and running stability will deteriorate. It has its drawbacks. Therefore, in order to reduce the amount of offset, some models have a notch in the center of the arm that faces the fixed case, but in this case, it is not possible to form a rib on the arm that faces the front wheel, and the The disadvantage is that it is not possible to obtain the strength of the arm body.

Purpose of the invention This invention was made in view of the above points, and the object is to obtain a rotating arm device for a front wheel drive device that has sufficient strength without increasing the amount of offset.

Summary of the invention This invention is a front wheel drive system in which a differential shaft and a wheel shaft to which front wheels are connected are connected via a power transmission shaft having a substantially vertical axis and a bevel gear. A fixed case that rotatably holds the wheel shaft is fixedly connected to the outer end of the shaft case that houses the differential shaft, and a rotating case that holds the wheel shaft rotatably around its axis surrounds the fixed case and transmits power. It is provided to be rotatable around the axis of the shaft, and is fixedly connected to the rotating case while surrounding the outer end facing the front wheel of the fixed case, and is also connected to the steering section and integrated with the rotating case. An arm body that rotates around the axis of the power transmission shaft is provided, the side surface of the arm body facing the front wheel is linear in the front-rear direction, and the side surface of the arm body facing the fixed case is shaped like a straight line in the front-rear direction. By curving it in an arch shape along the outer circumferential surface and forming rib portions at both ends, even if the arm body is made of a thick material, the amount of offset of the front wheel does not increase, improving turning performance and driving performance. The structure is designed to improve stability and to improve the strength of the arm body by rib portions formed at both ends of the arm body.

Embodiment of the invention An embodiment of the invention will be described based on the drawings. A bevel case 2 housing a differential device 1 is attached to the lower part of the tractor body (not shown), and a shaft case 3 is fixed to both left and right sides of the bevel case 2. A differential shaft 4 whose one end is connected to the differential device 1 is housed and held so as to be rotatable about its axis. A fixed case 5 is attached to the outer end of the shaft case 3.
is fixed to the fixed case 5, and an idle shaft 6, which is a power transmission shaft having a substantially vertical axis, is rotatably held around the axis. A bevel gear 7 is spline-fitted to the upper end of the idle shaft 6 located inside the fixed case 5, and a bevel gear 8 is similarly spline-fitted to the lower end of the idle shaft 6 protruding outside the fixed case 5. ing. Then, attach the front wheel 9 to the outer end.
A rotary case 11 is provided which holds a wheel shaft 10 connected to the idler shaft 10 rotatably around its axis, and this rotary case 11 protrudes from the lower side of the fixed case 5 and the fixed case 5 of the idle shaft 6. It is attached so as to be rotatable around the axis of the idle shaft 6 while surrounding the portion thereof. The bevel gear 12 spline-fitted to the wheel shaft 10 meshes with the bevel gear 8, and the bevel gear 13 spline-fitted to the outer end of the differential shaft 4 meshes with the bevel gear 7.

The upper end of the fixed case 5 is connected to a connecting arm 14 fixed to the rotating case 11 by a plurality of bolts 14a and a handle (not shown) serving as a steering section via a link 15 or the like. An arm body 17 in which a third arm 16 to be connected is integrally formed is rotatably supported around the axis of the idle shaft 6. The connecting arm 14 is arranged so as to surround the outer side of the fixed case 5 facing the front wheel 9.
The side surface of the connecting arm 14 facing the front wheel 9 is formed linearly in the front-rear direction, and a rib 18 is formed in the center thereof. It is curved in an arcuate shape along the outer circumferential surface, and rib portions 19 are formed at both ends in the front-rear direction.

In such a configuration, the differential shaft 4 rotates around its axis due to the driving force transmitted to the differential device 1 from the engine (not shown), and this rotation is caused by the bevel gear 1
3, 7, idle shaft 6, bevel gear 8, 1
2 to the wheel shaft 10, and the front wheels 9 are driven. In addition, steering force during turning is transmitted from the handle to the third arm 16 via the link 15 etc., and the arm body 17 and the rotating arm 11 rotate around the axis of the idle shaft 6, causing the front wheel 9 to rotate. be moved.

Therefore, a large bending moment acts on the connecting arm 14 when turning, etc., but this connecting arm 14 is formed of a thick material, and has rib portions 19 formed at both ends in the front and back direction, and a central portion of the connecting arm 14. Since the ribs 18 are also formed, sufficient strength can be obtained. Furthermore, since the side surface of the connecting arm 14 facing the fixed case 5 is curved in an arcuate shape along the outer peripheral surface of the fixed case 5, even if the connecting arm 14 is made of a thick material, the axis of the idle shaft 6 is The dimension from the front edge to the outer edge of the connecting arm 14 does not increase so much, therefore, an increase in the amount of offset of the front wheel 9 is prevented, and turning performance and running stability are improved.

Effects of the invention As described above, this invention has the front wheels fixed to the rotating case that holds the connected wheel shaft, and also connects the arm body connected to the steering section to the rotating case and the power source held in the fixed case. The arm body is rotatable around the axis of the transmission shaft, and the side surface of the arm body facing the fixed case is curved in an arcuate shape along the outer peripheral surface of the fixed case, and ribs are formed at both ends of the arm body. Even when formed from a thick member, it is possible to prevent the dimension from the axis of the power transmission shaft to the outer edge of the arm body from increasing.
It is possible to improve turning performance and running stability by preventing an increase in the offset amount of the front wheels, and the strength of the arm body is improved because wide rib portions are formed at both ends of the arm body. It has the following effects:

[Brief explanation of drawings]

The drawing shows one embodiment of this invention.
The figure is a vertical sectional front view, Figure 2 is an enlarged view of Figure 1 seen from the Z direction, and Figure 3 is an A-A in Figure 1.
FIG. 3...shaft case, 4...differential shaft,
5... Fixed case, 6... Idle shaft (power transmission shaft), 7-8... Bevel gear, 9... Front wheel, 10... Wheel shaft, 11... Rotating case, 12-13... Bevel gear, 17...Arm body.

Claims (1)

[Scope of utility model registration request] A pair of left and right differential shafts are housed in a shaft case, extend horizontally, and are rotatable about their axes.A power transmission shaft is provided at the outer end of a pair of left and right differential shafts that are housed in a shaft case and extend horizontally and are rotatable about their axes. A fixed case that is connected via a bevel gear and holds the power transmission shaft rotatably about its axis is fixedly connected to the outer end of the shaft case, and the inner end is connected to the power transmission shaft through the bevel gear. A rotary case that rotatably holds a wheel shaft, which is connected to the fixed case and has a front wheel connected to the outer end thereof, is rotatable around the axis of the power transmission shaft while surrounding the fixed case. The steering wheel is provided in the rotary case, and is fixedly connected to the rotary case while surrounding the outside of the fixed case, and is also connected to the steering section and rotates integrally with the rotary case around the axis of the power transmission shaft. A movable arm body is provided, a side surface of the arm body on the front wheel side is formed in a straight line, and a side surface of the arm body on the fixed case side is curved in an arch shape along the outer peripheral surface of the fixed case. A rotating arm device for a front wheel drive device, characterized in that rib portions are formed on both end sides.