JPH01293206A - Traveling wheel for weak soil - Google Patents

Abstract

PURPOSE:To improve an earth-moving property by providing an earth-moving fin, which falls to the rear of a rotating direction when touching the ground and elastically stands up when parting from the ground, between projections in the captioned traveling wheel in which the projections for generating a tractive force are projected for agricultural wheels etc. CONSTITUTION:Projections 2 for generating a tractive force are projected on the outer periphery of a traveling wheel 1 and fins 3 for earth-moving are projected between the projections 2 respectively. The fins 3 are made of rubber and formed to fall to the rear of a rotating direction when touching the ground and to stand up by its elastic force when parting from the ground. The weak soil 4 packed between the projections 2 is made to be positioned to the outer side of the fins 3 fallen by this constitution, and the soil 4 is sprung out from between the projections 2 to be excluded by the elastic restoring of the fins 3. The earth-moving property can be improved without lowering a tractive force by the constitution.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to running wheels for soft soil such as tires for running on rough terrain, agricultural wheels, crawlers, etc., and prevents a decrease in traction force due to soil adhesion to the running wheels. It is something to do.

(Prior art) On the outer periphery of running wheels such as tires and elastic tracks, protrusions such as lugs and blocks are provided at intervals in the circumferential direction in order to dig into the ground and generate traction force. .

The problem with the above-mentioned running wheels is that when running on soft soil such as snow or mud, snow or mud gets stuck between the protrusions, and the outer circumferential surface of the running wheels becomes uneven, making it impossible to generate sufficient traction force. occurs.

Here, as shown in FIG. 11, the density of mud, etc. that gets stuck between the protrusions 2 is reduced because the front surface 5 in the rotational direction of the protrusion 2 serves as the soil attacking surface, so mud, etc. gets clogged from the part close to the front surface 5. The parts are very dense.

Therefore, it has been proposed to improve soil removal performance by making the illustrated inclination angle θ2 of the front surface 5 in the rotational direction of the protrusion 2 larger than the inclination angle θ1 of the rear surface in the rotational direction.

Furthermore, it has been proposed that the width W of the protrusion 2 in the rotational direction is made smaller so that the protrusion 2 can be swung in the rotational direction, thereby improving soil removal performance.

(Problems to be Solved by the Invention) If the bevel angle θ2 of the protrusion 2 is increased, there is a problem that the weight of the running wheel increases and the rigidity of the protrusion 2 becomes too large.

If the dimension W of the protrusion 2 is made small, the rigidity of the protrusion 2 becomes too small, which poses no problem on soft soil, but there is a problem in that the traction force is insufficient when driving on a normal road surface.

The present invention aims to solve the above technical problems.

(Means for Solving the Problems) The present invention is characterized in that on the outer periphery of the running wheel body 1,
In a running wheel in which protrusions 2 that bite into the ground and generate traction force are provided at intervals in the circumferential direction, ejection fins 3 that stand up radially outward between the protrusions 2 are provided. The fins 3 are capable of collapsing toward the rear in the rotational direction when they make contact with the ground, and can be elastically restored to an upright state when separated from the ground.

(Function) At the ground contact portion of the running wheel, the fins 3 are in a state of being tilted toward the rear in the direction of rotation. Therefore, the soft soil that is stuck between the protrusions 2 exists on the radially outer side of the fins 3 in this fallen state. When the running wheel rotates from this state and the fins 3 separate from the ground, the fins 3 elastically return to the upright state. Due to this restoring force and the centrifugal force caused by the rotation, the soil that is stuck in the radially outward direction of the fins 3 receives a force directed in the radially outward direction from between the protrusions 2, and is discharged.

(Example) Embodiments of the present invention will be described below based on the drawings.

Figures 1 to 3 relate to tires for running on rough terrain, and the main body 1
is made of rubber. A plurality of protrusions 2 are provided on the outer periphery of the main body 1 at intervals in the circumferential direction in order to generate traction force.

Further, between each protrusion 2, a fin 3 is provided that stands up radially outward. This fin 3 is made of rubber and is integrally provided with the main body 1, and when it makes contact with the ground, it falls backward in the direction of rotation as shown in Figure 1, and when it separates from the ground, it falls down backwards. It elastically returns to the upright state as shown in Figure 2.

Note that the fins 3 may be connected to the main body 1 as a separate body.

As a result, as shown in Fig. 1, the soft soil 4 stuck between the protrusions is located outside the diameter of the fin in the fallen state.
When the fins 3 are restored by elastic force as shown in FIG. 2, the soft soil 4 receives the restoring force from the fins 3 and is ejected radially outward from between the protrusions 2 by competing with the centrifugal force caused by the rotation.

The protrusion 2 may be lug-shaped as shown in FIG. 4 or block-shaped as shown in FIG. 5. Moreover, it is most effective that the width of the fin 3 in the direction of the rotation axis spans the entire width of the protrusion 2 in the direction of the rotation axis.

In addition, the thickness of the fin 3 in the rotational circumferential direction is small at the radially outer end;
It is preferable to thicken it at the base. This is because a thicker root is preferable in terms of exerting elastic restoring force. Also,
This is because if the radial outer end is thick, the fin becomes difficult to fall down, the rotational direction front surface 5 of the protrusion 2 becomes difficult to grasp mud, and sufficient traction force cannot be exerted. Specifically, 1 to 7 cm at the outer diameter end.
, it is best to make it 3 to 7 mm at the base.

Moreover, as shown in FIG. 6, the inclination angle θ toward the rear in the rotational direction with respect to the normal line of the fin 3 is preferably set to 0 to 45 degrees from the viewpoint of ease of falling and restoring force.

The height H of the fin 3 is such that when it touches the ground and is pushed down, its radial outer end becomes equal to the height h of the protrusion 2 as shown in the seventh figure, or the height H of the protrusion 2 as shown in the sixth figure. It is preferable that the height h be lower than the height h. This is because if the fin height H becomes larger than that, the fin 3 will cover the radially outer end surface 6 of the protrusion 2 when touching the ground, reducing the traction force. In addition, the height H of the fin 3 is such that when it is pushed down, its radial outer end is
It is preferable that the height is at least abutting the base of the front surface 5 of the projection 2 in the rotational direction. This is because, as shown in Figure 11, mud etc. clog the protrusion 2 sequentially from the part near the front face 5 in the rotating direction (as indicated by chain lines a, b, c, and d in the figure), and the clogging density in that part is Since it is high, if the outer diameter end of the fin 3 contacts the base of the protrusion 2 when pushed down, soil can be removed at an early stage of clogging with mud, etc., and clogging with mud etc. can be effectively prevented. Therefore, the distance from the base of the fin 3 to the base of the front surface 5 in the rotation direction of the protrusion 2 is 1-11, the distance to the radial outer end of the front surface 5 in the rotation direction is 2b, and the tangential direction of the running wheel when the fin 3 falls down. If the angle formed is θ, the height H of the fin is ! , ≦H≦fb/CO3θ1. However, dimensions other than those described above may be used.

Further, a plurality of fins 3 may be provided between each protrusion 2. In addition, taking into account the reverse rotation, the front and rear surfaces 5 in the rotational direction of the protrusion 2 are
, 7 may be provided with fins 3 having the above dimensions.

In addition, as the running axle, ultra-low pressure tires (T
The present invention can also be applied to ATU tires (ATU tires of ATMA standard), agricultural tires (AG tires), rice transplanter wheels, endless tracks for crawler vehicles, and the like.

FIGS. 8 and 9 show experimental results when tires with and without the fins 3 of the present invention were run on wet fields and on sloped snowy roads.

For the experiment, 25X12.9 AT 503 tires were used, the height of lug 2 was 15.5 mm, and the wall thickness of lug 2 was 13 m.
a+, the distance between lugs 2 is 68.5 mm, and the thickness of fin 3 is 1
．． The height of the fins 3 was 20 mm, the angle of the fins 3 with respect to the normal was 0 degrees, and the arrangement pattern of the lugs 2 and fins 3 was as shown in FIG. Furthermore, the fins 3 were attached to the tire with an adhesive, and were provided only on the ground-contacting part, rather than over the entire width of the tire in the rotational axis direction.

Figure 8 shows the results when the viscosity of mud was varied in a wet field with a mud depth of approximately 20 cm, with the horizontal axis representing the viscosity of the mud and the vertical axis representing the travel distance within a certain period of time. In the figure, the solid line shows the case where the fin 3 is provided, and the broken line shows the case where the fin 3 is not provided. Further, FIG. 9 shows the results when the snow depth was varied on a slope of approximately 6 to 10 degrees, with the horizontal axis representing the snow depth and the vertical axis representing the pitching distance.

In the figure, the solid line is the one with the fin 3 provided, and the broken line is the one without the fin 3. These results show that by providing the fins 3, it is possible to effectively prevent a decrease in traction force on soft soil.

(Effects of the Invention) According to the present invention, the fins provided on the outer periphery of the running wheel body dislodge soft soil stuck between the protrusions that generate traction force by collapsing and elastically restoring the soil. It is possible to effectively prevent a decrease in traction force due to clogging of soft soil.

[Brief explanation of the drawing]

Figures 1 to 10 relate to an embodiment of the present invention; Figure 1 is a sectional view of the main part in a state where soft soil is clogged between the protrusions of the running wheel, and Figure 2 is a sectional view of the main part of the running wheel with soft soil clogged between the protrusions. 3 is a side view of the main part of the running wheel, FIGS. 4 and 5 are views showing different arrangements of protrusions and fins, and FIGS. 6 and 7 are The figures are cross-sectional views of the main parts showing the dimensional relationships of different fins, Figure 8 is a diagram showing the running performance of the running wheels in wet fields, Figure 9 is a diagram showing the running performance of the running wheels on snowy roads, FIG. 10 is a diagram showing the arrangement of the fins and protrusions of the running wheel used in the running experiment, and FIG. 11 is a sectional view of the running wheel according to a conventional example. 1...Body, 2...Protrusion, 3...Fin. Patent applicant: Agent of Otsu Tire Co., Ltd.
Patent Attorney Yasu 1) Toshio Figure 70 Figure 4 Figure 5 41 Width i? 4 f!

Claims (1)

[Claims] (1) In a running wheel in which protrusions 2 that dig into the ground and generate traction force are provided on the outer periphery of the running wheel main body 1 at intervals in the circumferential direction, between each of the protrusions 2, a radially outward A fin 3 for soil removal that stands up toward the ground is provided, and this fin 3 falls backward in the direction of rotation when it makes contact with the ground, and elastically returns to the upright state when it separates from the ground. A running wheel for soft soil, which is characterized by being able to