JP2009248924A - Rubber crawler - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rubber crawler wherein damage at a portion where a track roller rolls is suppressed. <P>SOLUTION: In the rubber crawler consisting of a band-like body 1 in which a plurality of core bars 2 are berried and fixed in a rubber layer 1a together with a reinforced layer 5 and their end parts are linked in a manner twistable around each other between the driving wheel 4 and a driven wheel intervened with the track roller 3 and held in an endless manner, the core bar 2 is structured by a pair of projections 2a, 2b for separating and forming a single route S, having an outside wall facing against a side wall of the track roller 3, for passing the driving wheel 4 and the driven wheel in a clearance M between inside walls and a pair of blades 2c, 2d which are integrally continued with base parts 2' of the respective projections 2a, 2b at their root portions wherein end edges in the width direction of the rubber crawler are arranged as tip ends. A multi-stage slope consisting of a plurality of level differences of which angles become gradually smaller toward the base parts of the projections is provided for each outside wall of the respective projections 2a, 2b. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  TECHNICAL FIELD The present invention relates to a rubber crawler mounted on a construction machine such as a hydraulic excavator, an agricultural machine such as a combine or a tractor, and other crawler type vehicles, and a metal core caused by stress concentration in a rolling part of a wheel. And try to avoid peeling of the rubber layer.

  A crawler-type vehicle traveling body has an endless track by winding a rubber crawler between a sprocket-type driving wheel connected to a driving means such as a hydraulic motor and a driven wheel rotatably supported by a vehicle frame. The wheel is made to roll between the driving wheel and the driven wheel, thereby enabling traveling on rough terrain.

In the rubber crawler, a plurality of metal cores are embedded and fixed in an annular manner in a rubber layer forming a belt-like body, and the traveling body rotates on the outer side (region between the metal core and the ground contact surface). It has a structure in which a reinforcing layer in which a plurality of steel cords extended along the direction are arranged along the width direction is arranged (see, for example, Patent Document 1).
JP-A-6-234378

  By the way, this type of crawler belt with a cored bar embedded and fixed tends to concentrate stress in the area where the wheel rolls (the R part where the cored bar and the blade join), and the rubber layer is destroyed at that part, There was a problem that caused a so-called worm-eaten phenomenon in which the rubber layer was peeled off from the metal core and a plurality of small holes were formed.

  Although it is effective to increase the thickness of the rubber layer at the part where the wheel rolls, the height of the protrusion of the core metal is reduced to avoid the occurrence of such a worm-eaten phenomenon. There is a limit to increasing the thickness of the rubber layer, and a solution to this problem has been demanded.

  An object of the present invention is to propose a novel rubber crawler capable of avoiding the worm-eaten phenomenon caused by stress concentration without reducing the wheel-removing property.

The present invention consists of a belt-like body in which a plurality of metal cores are embedded and fixed in a rubber layer together with a reinforcing layer, and the ends thereof can be wound between a driving wheel and a driven wheel with a roller wheel interposed therebetween. A rubber crawler that is linked and held endlessly,
The metal core has an outer wall facing the side wall of the wheel, a pair of protrusions defining a single path through which the driving wheel and the driven wheel pass in a gap between the inner side walls, and a base portion of each protrusion It consists of a pair of blades that are integrally connected to each other at the root and have the edge in the width direction of the rubber crawler as the tip.
The rubber crawler is characterized in that the outer wall of each projection is provided with a multi-step slope composed of a plurality of steps with gradually decreasing angles toward the base of the projection.

  In the above-described rubber crawler, it is preferable that the multi-stage inclination is formed in at least two stages of the protrusion tip side wall and the protrusion base side wall, and the protrusion base side wall has an angle smaller than the angle of the protrusion tip side wall.

In addition, when the angle between the protrusion tip side wall and the blade root outer surface (flat horizontal surface) is β and the angle between the protrusion base side wall and the blade root outer surface is α,
90 ° <α <β,
α = 90 ° <β or
α <90 ° <β
It is preferable to satisfy any one of the conditions.

  It is desirable that at least the base outer surface of the blade is a flat surface or an inclined surface that is inclined downward toward the edge of the roller belt, and the base side wall is a circular arc surface having a concave outer surface. It is preferable to comprise.

  The outer wall of the core bar protrusion (the part facing the side wall of the wheel) cannot be made extremely steep due to matching with the fuselage, etc., but the outer wall of each protrusion faces the base of the protrusion. By providing a multi-step slope with a gradually reduced angle, it is possible to increase the volume of rubber at that portion and to relieve stress concentration.

  The multistage inclination has at least two steps of the protrusion tip side wall and the protrusion base side wall, and the effect of reducing the stress concentration is high by setting the protrusion base side wall to an angle smaller than the angle of the protrusion tip side wall.

  90 ° <α <β, α = 90 °, an angle α formed between the protrusion tip side wall of each protrusion and the blade root outer surface and an angle β formed between the protrusion base side wall of each protrusion and the blade root outer surface <Β or α <90 ° <β (only the protrusion base side wall is steeply inclined, and a state where a two-step inclination is formed as a whole) makes it possible to increase the rubber volume. Stress concentration can be alleviated at a site where an insect erosion phenomenon is likely to occur.

Hereinafter, the present invention will be described more specifically with reference to the drawings.
FIG. 1 is an external perspective view schematically showing a state in which a rubber crawler according to the present invention is wound between a driving wheel and a driven wheel (not shown), and FIG. 2 is a cross-sectional view of an essential part thereof. FIG.

The number 1 in FIGS. 1 and 2 is a strip. This belt-like body 1 is composed of a rubber layer 1a and a plurality of metal cores 2 embedded and fixed in the rubber layer 1a with a minute gap therebetween, and driving wheels 4 having rollers 3 interposed between the ends thereof. An endless track is formed by linking the driven wheels (not shown) so as to be wound around each other and holding them endlessly. Here, the ground portion T becomes the outer periphery side of the band-like body 1 to form a land portion such as a lug, the inner peripheral side of the rotary wheel 3, the drive wheels 4, a divided region T ₁ of the driven wheel or the like is disposed.

  The cored bar 2 is a pair of left and right protrusions 2a, 2b provided in the central region in the width direction, and a pair of bases 2 'of the protrusions 2a, 2b that are integrally connected to each other at the root and having the end in the width direction of the rubber crawler as a tip. Blades 2c and 2d.

As shown in FIG. 2, the protrusions 2a and 2b of the cored bar 2 are provided with a multi-step inclination composed of a plurality of steps with progressively smaller angles toward the protrusions 2a and 2b on the outer wall facing the side wall of the wheel 3. It has been. Here, in this example, the outer wall is connected to the protrusion tip side walls 2a ₁ and 2b ₁ continuously to the lower ends thereof, and the protrusion base side walls 2a ₂ and 2b that are steeper than the protrusion tip side walls 2a ₁ and 2b _1. It is shown as consisting of _two-stage. The angle formed by the protrusion base side walls 2a ₂ , 2b ₂ connected to the protrusion tip side walls 2a ₁ , 2b ₁ of the protrusions 2a, 2b and the outer base surfaces of the blades 2c, 2d is α, and the protrusion base side walls 2a ₂ , Satisfy one of the following conditions: 90 ° <α <β, α = 90 ° <β, or α <90 ° <β, where β is the angle between 2b ₂ and the outer root surface of blade 2c, 2d In the gap M between the inner walls, a single path S through which the driving wheel 4 and the driven wheel pass is formed (see FIG. 2). It is particularly desirable that the protrusion base side walls 2a ₂ and 2b ₂ have arcuate surfaces so that they can smoothly connect to the outer root surfaces of the blades 2c and 2d.

Reference numeral 5 denotes a reinforcing layer provided on the outer peripheral side of the cored bar 2. The reinforcing layer 5 is composed of at least one layer in which a plurality of steel cords extending along the circumference of the belt-like body 1 are arranged in the width direction, and is embedded and fixed in the rubber layer 1a together with the cored bar 2. Further, 6 is a flat surface (coincidence with the outer surface of the rubber layer 1a) provided adjacent to the protrusions 2a and 2b of the cored bar 2 on the inner peripheral side of the strip 1. The flat surface 6 has an outer surface located at a boundary P (see FIG. 2) between the protrusion tip side walls 2a ₁ and 2b ₁ and the protrusion base side walls 2a ₂ and 2b ₂ of the core bars 2a and 2b (the rubber layer 1a). It matches the outer surface, and the thickness W of the rubber layer 1a at this portion is thicker than the conventional one.) The rolling wheel 3 rolls along the flat surface 6. Here, the boundary P may exist above the flat surface 6 as shown in FIG. 3 (however, if the dimension from the flat surface 6 to the boundary P is W ′, W ′ <W.

  Reference numeral 7 denotes an opening (engagement hole) penetrating from the inner peripheral side to the outer peripheral side of the strip 1 in a single path S (the center in the width direction of the strip 1) through which the driving wheel 4 and the driven wheel pass. The openings 7 are provided at intervals over the entire circumference of the belt-like body 1 (provided in a portion of a minute gap where the cored bar 2 is not arranged), and the protrusion 4a of the drive wheel 4 is adapted here. To do.

  Of the rolling wheels 3 interposed between the drive wheels 4 and the driven wheels, the rolling wheels 3 located on the lower surface (the side to be grounded) transmit the load of the fuselage to the rubber track so that the entire grounding part is securely grounded. On the other hand, a roller wheel (not shown) located on the upper surface is supported so that the tension of the rubber crawler is always kept constant between the driving wheel 4 and the driven wheel, and here, by a driving means such as a hydraulic motor. When the driving wheel 4 is rotated, the rotational force is transmitted to the crawler belt through the opening 7 adapted to the protrusion 4a of the driving wheel 4, and the crawler belt rotates between the driven wheel and the airframe to rotate. Therefore, it travels.

  4 (a), 4 (b) to 6 (a), (b) show other embodiments of a rubber crawler according to the present invention with respect to the main part thereof.

4 (a) and 4 (b) show a case where 90 ° <α <β for the type having the flat surface f and the inclined surface k at the roots of the blades 2c and 2d. FIGS. 5 (a) and 5 (b) show cases where α = 90 ° <β for the types having the flat surface f and the inclined surface k at the roots of the blades 2c and 2d, respectively. 6 (a) and 6 (b) show a case where α <90 ° <β for a type having a flat surface f and an inclined surface k at the roots of the blades 2c and 2d, respectively. In either case, the protrusion tip side wall 2a _{1 in} which the angle α formed between the protrusion base side walls 2a ₂ and 2b ₂ of the protrusions 2a ₂ and 2b ₂ provided on the core metal 2 and the blades 2c and 2d faces the side surface of the wheel 4. since steepens compared to 2b _1, it is possible to increase the rubber volume without affecting the derailing resistance, so that the stress concentration is alleviated at the site.

The total height of the protrusion of the cored bar 2 (from the point 0 where the outer surface of the blades 2c, 2d and the axis L of the protrusions 2a, 2b intersect, from there to the tip 0 'of the protrusions 2a, 2b) and dimension.) when was is h, the projecting tip sidewall 2a _1, 2b ₁ of the height h _{1 (the} same as the thickness W of the rubber layer 1a), or projection base side wall 2a _2, the height of 2b ₂ h ₂ Is set in the range of 25 to 75% of the total height h.

  To manufacture a rubber crawler, first, as shown in FIG. 7, the cap rubber (rubber side rubber) 8 that forms the ground contact portion T of the rubber layer 1 and the intermediate rubber that forms the reinforcing layer 5 (steel cord covered with rubber) And the inner rubber (roller passage rubber) 10 that forms the inner peripheral surface of the belt-like body 1 and the inner rubber (roller passage rubber) 10 are respectively molded. In order to ensure adhesion, the base rubber (blasting) is performed, and then the inner rubber 7 and the core metal 2 are set in the mold 11 (the core metal 2 is embedded in the inner rubber 7 from the projections 2a and 2b). At the same time, the intermediate rubber 9 is sequentially disposed, and the cap rubber 5 is disposed thereon, and then a molded body having a desired cross-sectional shape is formed. The molded body is pressed, heated, and vulcanized in the laminating direction to integrate the members, and the ends are bonded together to form a ring, and then the bonded portions are vulcanized. Techniques are applied.

Example A vehicle (tractor) equipped with a rubber crawler (α = 90 °, β = 115 °) having a width of 450 mm, a link number of 50, and a pitch of 90 mm having the cross-sectional shape shown in FIG. 5 above, water + crushed stone + A running test was carried out to positively cause worm-feeding in a sandy field. As a result, it was confirmed that the crawler according to the present invention has a durability that is doubled or exceeded that of the conventional crawler.

  It is possible to provide a rubber crawler capable of suppressing the occurrence of the worm-eating phenomenon that has occurred at the site where the wheel rolls and extending the service life.

It is an external appearance perspective view of the principal part showing typically an embodiment of a rubber crawler according to the present invention. FIG. 2 is a view showing a cross section of the rubber crawler shown in FIG. FIG. 3 is a diagram showing a main part of FIG. (A) (b) is the figure which showed other embodiment of the rubber crawler according to this invention. (A) (b) is the figure which showed other embodiment of the rubber crawler according to this invention. (A) (b) is the figure which showed other embodiment of the rubber crawler according to this invention. It is explanatory drawing of the manufacturing point of a rubber crawler.

Explanation of symbols

1 Band
1a Rubber layer
2 Core
2a Protrusion
2b Protrusion
2c blade
2d blade
3 Rolling wheels
4 Drive wheels
4a protrusion
5 Reinforcing layer
6 Flat surface
7 opening
8 Cap rubber
9 Intermediate rubber
10 Inner rubber
11 Mold
T Grounding section
T ₁ section area
M Clearance
S single path

Claims (6)

It consists of a belt-like body in which a plurality of metal cores are embedded and fixed in a rubber layer together with a reinforcing layer. Ends of the metal cores are endlessly linked so that they can be wound between a drive wheel and a driven wheel through which a wheel is interposed. The rubber crawler held in the
The cored bar has an outer wall facing the side wall of the wheel, a pair of protrusions defining a single path through which the driving wheel and the driven wheel pass in a gap between the inner side walls, and a base portion of each protrusion It consists of a pair of blades that are integrally connected to each other at the root and have the edge in the width direction of the rubber crawler as the tip
A rubber crawler characterized in that a multi-step slope composed of a plurality of steps with gradually decreasing angles toward the base of the protrusion is provided on the outer wall of the protrusion.   2. The rubber crawler according to claim 1, wherein the multi-step inclination includes at least two stages of a protrusion tip side wall and a protrusion base side wall, and the protrusion base side wall has an angle smaller than an angle of the protrusion tip side wall. When the angle between the protrusion tip side wall and the blade root outer surface is β and the angle between the protrusion base side wall and the blade root outer surface is α,
90 ° <α <β,
α = 90 ° <β or
α <90 ° <β,
3. The rubber crawler according to claim 2, satisfying any one of the conditions.   4. The rubber crawler according to claim 3, wherein at least a base outer surface of the blade is a flat surface.   4. The rubber crawler according to claim 3, wherein at least a root outer surface of the blade is an inclined surface.   6. The rubber crawler according to claim 2, wherein the protrusion base side wall is formed of an arc surface having a concave outer surface.

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