JP4137900B2 - Agricultural wheels - Google Patents

Description

  The present invention relates to agricultural wheels.

  Agricultural machines such as management machines and rice transplanters use agricultural wheels in which rubber is baked on metal rims. The agricultural wheel includes a number of lugs protruding in the radial direction. This lug is provided with a kick surface and a back surface formed of a flat surface or a curved surface. Since the kick surface and the rear surface shear the mud of the field or paddy field, a propulsive force is generated in the airframe.

  In particular, in agricultural wheels used in Fukada, called super wet fields, the traction and buoyancy are maintained, so the width of the lugs is increased. Such a wheel suppresses slipping, so that stacking can be avoided.

Agricultural wheels with reduced wheel mass and reduced mud adhesion and winding during travel are disclosed in JP-A-9-286201. This wheel is provided with a notch on the side surface of the lug.
JP-A-9-286201

  In the agricultural wheel in which the width in the axial direction of the lug is expanded because the traction force and the buoyancy are maintained, the traveling trace of the wheel becomes large. If the running track of the wheel becomes large, the groove erasing device (float) provided in the airframe will not work effectively, so the seedling planting ability may be reduced.

  An object of the present invention is to provide an agricultural wheel in which the running trace of the wheel is kept small and the traction force and buoyancy are improved.

  The agricultural wheel according to the present invention includes a rim made of a metal pipe and an elastic ring body to be baked on the rim. This elastic ring body includes a lug protruding outward in the radial direction. The lug includes a rectilinear guide portion disposed on the equator plane and a number of propulsion portions extending axially outward from the rectilinear guide portion. These propulsion units are alternately arranged on the left and right in the rotation direction. The propulsion unit includes a kick surface on the rotational direction side and a back surface on the opposite side. The kick surface and the back surface have a number of steps.

  Preferably, in this wheel, the step includes a vertical surface extending in the radial direction and a bottom surface extending in the rotational direction. The length of this vertical plane is 2 mm or more and 10 mm or less. The length of the bottom surface is 2 mm or more and 10 mm or less.

  Since this agricultural wheel has many steps on the kicking surface and back surface of the propulsion unit provided on the lug, its surface area is larger than that of the propulsion unit composed of a flat surface or a curved surface without the step. . Therefore, this wheel has a greater ability to trap mud. In addition, since the kick surface is provided with a vertical surface, the force with which the mud is sheared is increased. A wheel that has improved the ability to trap mud and the shearing force of mud improves buoyancy and traction. Since the traction force and the buoyancy are improved, the width of the lug does not need to be widened, so the travel trace can be made small. In a rice transplanter equipped with such wheels, the propulsive force of the aircraft is improved without lowering the plantability of seedlings.

  Hereinafter, the present invention will be described in detail based on preferred embodiments with appropriate reference to the drawings.

  FIG. 1 is a side view showing a part of an agricultural wheel 2 according to an embodiment of the present invention. In FIG. 1, the direction perpendicular to the paper surface is the axial direction of the wheel 2. An arrow line A represents the rotation direction. FIG. 2 is an enlarged cross-sectional view along the line II-II of the wheel 2 of FIG. In FIG. 2, the vertical direction is the radial direction of the wheel 2, and the horizontal direction is the axial direction of the wheel 2. The wheel 2 includes a boss, a spoke 4, a rim 6, and an elastic ring body 8. Although not shown, the boss is disposed at the center of the wheel 2. An axle is fitted to this boss. The boss, the spoke 4 and the rim 6 form an iron wheel.

  The spoke 4 extends radially outward from the boss. Although not shown, the four spokes 4 are used in the wheel 2. Three or five or more spokes 4 may be used. From the viewpoint of weight reduction of the wheel 2, the spoke 4 provided on the wheel 2 is made of a metal pipe. Examples of the material of the spoke 4 and the boss include steel and stainless steel. Stainless steel is preferred from the viewpoint of corrosion resistance. The boss and the spoke 4 are connected by welding. The boss and the spoke 4 may be connected to each other by a method such as riveting or bolting by providing a connecting piece and a flange corresponding to the connecting piece.

  The rim 6 is processed into a ring shape. From the viewpoint of reducing the weight of the wheel 2, the rim 6 is made of a metal pipe. The rim 6 is connected to the end of the spoke 4. Examples of the material of the rim 6 include steel and stainless steel. Stainless steel is preferred from the viewpoint of corrosion resistance. In the wheel 2, the spoke 4 and the rim 6 are connected by welding. The spoke 4 and the rim 6 may be connected to each other by a method such as riveting or bolting by providing a connecting piece and a flange corresponding to the connecting piece.

  The elastic ring body 8 is disposed on the radially outer side of the iron wheel. The elastic ring body 8 includes a lug 10 that protrudes outward in the radial direction. The lug 10 includes a straight guide 12, a propulsion unit 14, and an inclined surface 16. The rectilinear guidance portion 12 is disposed on the equator of the wheel 2. The propulsion unit 14 extends outward in the axial direction from the straight guide 12. The propulsion units 14 are alternately arranged on the left and right sides in the rotation direction on both sides of the linear guide unit 12. The inclined surface 16 is located between the two propulsion units 14 arranged in the rotation direction. The inclined surface 16 is a side surface of the straight guide 12. A propulsion unit 14 is disposed on the opposite side of the inclined surface 16 in the axial direction.

  The straight guide 12 includes a protrusion 18. The protrusions 18 are arranged in the rotation direction. Since the straight guiding part 12 is provided with the protrusion 18, the wheel 2 is excellent in traction performance. In the wheel 2 having excellent traction performance, the traction force is increased.

  The propulsion unit 14 includes a kick surface 20 on the rotation direction side and a back surface 22 on the opposite side to the rotation direction. The kick surface 20 shears mud. In this elastic ring body 8, the back surface 22 provided in the propulsion unit 14 in the front in the rotation direction, the kick surface 20 of the propulsion unit 14 located behind the back surface, and the inclined surface positioned between the back surface 22 and the kick surface 20. An enclosure is formed from 16. When traveling, the enclosure captures mud.

  The kick surface 20 and the back surface 22 provided in the propulsion unit 14 are provided with a number of steps 24. The step 24 includes a vertical surface 26 extending in the radial direction and a bottom surface 28 extending in the rotation direction. In addition, the axial direction length of the step 24 in this wheel 2 is shortened as the step 24 on the radially inner side in accordance with the shape of the inclined surface 16.

  Since the wheel 2 includes a large number of steps 24, the surface area of the wheel 2 is larger than that of the propulsion unit 14 formed of a flat surface or a curved surface that does not include the steps 24. Therefore, in this wheel 2, the catching property of the mud by an enclosure part becomes large. In addition, since the kick surface 20 is provided with a vertical surface 26, the force with which the mud is sheared is increased. Since the buoyancy and the traction force are improved in the wheel 2 in which the trapping property of the mud and the force by which the mud is sheared are increased, the propulsive force of the wheel 2 is increased. Since the slip of the wheel 2 is suppressed in the super wet field, stacking can be avoided. In addition to this, since the width of the lug 10 is reduced, the running trace can be reduced. In the rice transplanter to which the wheel 2 is attached, the groove erasing device (float) provided in the machine body works effectively, so that the seedling planting property is improved.

  In FIG. 1, the double arrow line LA represents the length of the vertical surface 26. A double arrow line LB represents the length of the bottom surface 28. An angle α represents an angle formed by the vertical surface 26 and the bottom surface 28. The length LA of the vertical surface 26 is 2 mm or more and 10 mm or less. By setting the length LA of the vertical surface 26 to 2 mm or more, the shearing force against the mud is improved. The wheel 2 with improved shearing force against mud is excellent in traction and buoyancy. In this respect, the length LA of the vertical surface 26 is more preferably 3 mm or more, and particularly preferably 4 mm or more. By setting the length LA of the vertical surface 26 to 10 mm or less, traction force and buoyancy are maintained. From this viewpoint, the length LA of the vertical surface 26 is preferably 9 mm or less, and particularly preferably 8 mm or less.

  The length LB of the bottom surface 28 is 2 mm or more and 10 mm or less. By setting the length LB of the bottom surface 28 to 2 mm or more, the shearing force against the mud is improved. The wheel 2 with improved shearing force against mud is excellent in traction and buoyancy. In this respect, the length LB of the bottom surface 28 is more preferably 3 mm or more, and particularly preferably 4 mm or more. By setting the length LB of the bottom surface 28 to 10 mm or less, the traction force and the buoyancy are maintained. From this viewpoint, the length LB of the bottom surface 28 is preferably 9 mm or less, and particularly preferably 8 mm or less.

  The angle α formed by the vertical surface 26 and the bottom surface 28 is preferably 90 ° or more and 120 ° or less. By setting the angle α to 90 ° or more, adhesion and winding of mud can be suppressed. In the wheel 2 in which the adhesion and winding of the mud are suppressed, the mud does not fall from a high position, so that the planted seedling is not damaged. From this viewpoint, the angle α is more preferably 91 ° or more, and particularly preferably 92 ° or more. By setting the angle α to 120 ° or less, the shearing force on the mud is improved. The wheel 2 with improved shearing force against mud is excellent in traction and buoyancy. In this respect, the angle α is preferably 115 ° or less, and particularly preferably 110 ° or less.

  The elastic ring body 8 is made of a crosslinked rubber. Examples of the material of the crosslinked rubber include natural rubber, styrene-butadiene rubber, butadiene rubber, and isoprene rubber. From the viewpoint of versatility, natural rubber is preferable.

  The hardness of the crosslinked rubber is preferably 53 or more and 75 or less. By setting the hardness to 53 or more, the propulsive force of the airframe in the mud is improved. In this respect, the hardness is more preferably equal to or greater than 56, and particularly preferably equal to or greater than 60. By setting the hardness to 75 or less, generation of vibration is suppressed. Therefore, the agricultural machine equipped with this wheel 2 is excellent in operability. In this respect, the hardness is more preferably equal to or less than 70, and particularly preferably equal to or less than 65.

  In the present invention, the hardness is measured by a type A durometer. A test piece for measurement is cut out from the wheel 2. Three sheet-like test pieces having a thickness of 1.0 mm are stacked and measured.

  The manufacturing method of this agricultural wheel 2 is as follows. First, the boss, the spoke 4 and the rim 6 are integrated by welding to produce an iron car. Next, the steel wheel is shot blasted to remove oil, dirt, and the like adhering to the steel wheel. In the shot blasted iron wheel, an adhesive is applied to the rim 6 or the like covered with the elastic ring body 8, and then a baking process is performed. On the other hand, the rubber composition in which the elastic ring body 8 is formed is manufactured using a kneader such as a Banbury mixer. This rubber composition is processed into a preform with the shape of the wheel 2 taken into consideration. Thereafter, the iron wheel coated with the adhesive and the preform are put into a vulcanizer, and pressurized and heated. By this pressurization and heating, the rubber composition of the preformed body flows. The rubber composition of the preformed body undergoes a crosslinking reaction by heating. The rubber composition of the preform is completely crosslinked, and the elastic ring body 8 is molded. Simultaneously with this crosslinking reaction, the rubber composition, the adhesive, and the steel wheel as the adherend cause an adhesion reaction. By this adhesion reaction, the elastic ring body 8 is baked on the iron wheel. In this way, the wheel 2 shown in FIG. 1 is obtained. The wheel 2 is manufactured by separately manufacturing the boss and spoke 4 integrated and the rim 6 and elastic ring body 8 integrated separately and assembling in the final process. May be.

  Examples of the adhesive used for baking the elastic ring body 8 and the iron wheel include isocyanate adhesives and phenol resin adhesives. From the viewpoint of versatility, an isocyanate-based adhesive is preferable.

  The dimension and angle of the wheel 2 are measured in a state where the wheel 2 is incorporated in the regular rim 6. During the measurement, no load is applied to the wheel 2. In this specification, the normal rim 6 means the rim 6 defined in the standard on which the wheel 2 depends. “Standard rim” in the JATMA standard, “Design Rim” in the TRA standard, and “Measuring Rim” in the ETRTO standard are regular rims 6.

  Hereinafter, the effects of the present invention will be clarified by examples. However, the present invention should not be construed in a limited manner based on the description of the examples.

[Example 1]
Agricultural wheels of Example 1 having the basic configuration shown in FIGS. 1 and 2 and having the specifications shown in Table 1 below were obtained. This wheel is provided with steps on the kick surface and back surface of the propulsion unit. The length of the vertical plane in which this step is formed is 2 mm. The length of the bottom surface is 2 mm. The angle α formed by the vertical surface and the bottom surface is 90 °. The axial width of the propulsion unit is the same as that of Comparative Example 1 shown below.

[Comparative Example 1]
Agricultural wheels were obtained in the same manner as in Example 1 except that steps were not provided on the kick surface and back surface of the propulsion unit. This agricultural wheel is a conventional wheel.

[Examples 2 to 5]
A wheel was obtained in the same manner as in Example 1 except that the length LA of the vertical surface, the length LB of the bottom surface, the angle α, and the axial width of the propulsion unit were as shown in Table 1 below. Agricultural wheels were obtained in the same manner as in Example 1 except that steps were not provided on the kick surface and back surface of the propulsion unit.

[Comparative Example 2]
Agricultural wheels were obtained in the same manner as Comparative Example 1 except that the axial width of the propulsion unit was expanded. This wheel also has no step on the kicking surface and the back surface of the propulsion unit.

[Running and seedling planting evaluation]
A prototype wheel was installed in the rice transplanter. In the test course where the wet field was simulated, the running and seedling planting were evaluated. As for running performance, the occurrence of slip was evaluated. If slip generation was observed, A was indicated, and if slip generation was not observed, B was expressed. Regarding the seedling planting ability, a sensory evaluation was performed in which 10 points on the seedling arrangement condition and the seedling damage condition were rated as full marks. It shows that it is excellent in seedling planting property, so that this figure is large. The results are shown in Table 1 below.

  As shown in Table 1, it was confirmed that the agricultural wheels of the examples were excellent in seedling plantability without causing slip. From this evaluation result, the superiority of the present invention is clear.

  The agricultural wheel according to the present invention can be mounted on various agricultural machines.

FIG. 1 is a side view showing a part of an agricultural wheel according to an embodiment of the present invention. FIG. 2 is an enlarged cross-sectional view along the line II-II of the wheel of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 2 ... Wheel 4 ... Spoke 6 ... Rim 8 ... Elastic ring body 10 ... Lug 12 ... Straight-forward guide part 14 ... Propulsion part 16 ... Inclined surface 18 ... Projection 20 ... Kick surface 22 ... Bottom surface 24 ... Step 26 ... Vertical surface 28 ... Bottom surface

Claims (2)

It has a rim made of metal pipe and an elastic ring body that is baked on this rim.
This elastic ring body is provided with a lug projecting radially outward,
The lug includes a rectilinear guide portion disposed on the equator, and a number of propulsion portions extending axially outward from the rectilinear guide portion.
These propulsion parts are alternately arranged on the left and right in the rotation direction,
This propulsion unit has a kick surface on the rotational direction side and a back surface on the opposite side,
Agricultural wheels in which the kick surface and the back surface are provided with a number of steps. The step includes a vertical surface extending in the radial direction and a bottom surface extending in the rotational direction,
The wheel according to claim 1, wherein the length of the vertical surface is 2 mm or more and 10 mm or less, and the length of the bottom surface is 2 mm or more and 10 mm or less.

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