JP5227813B2 - Elastic crawler - Google Patents

Description

  The present invention relates to a traveling vehicle such as a civil engineering work machine, a construction working machine, or an agricultural working machine, and an elastic crawler mounted on the traveling vehicle.

Elastic crawlers formed in endless belts for crawler-type traveling vehicles such as civil engineering work machines, construction work machines used in residential land development, road construction, river maintenance, etc. Is installed.
In such an elastic crawler, core bars are embedded at equal intervals in the circumferential direction (circulation direction), and a pair of projections for guiding a wheel or the like are spaced from the core bars at intervals in the width direction. Projects to the circumferential side. Further, on the outer side of each of the protrusions arranged in the width direction on the inner circumferential surface of the elastic crawler, a wheel running surface for running the wheel continuously extends in the circumferential direction with a certain width. Yes.

In the conventional elastic crawler 41 as shown in FIG. 3, the respective wheel running surfaces 42, 42 extending in the circumferential direction at intervals in the width direction are flat and the same virtual plane that is horizontal when grounded. It was formed so as to be included in IS (Patent Document 1).
As described above, the elastic crawler 41 in which the roller running surfaces 42 and 42 on both sides in the width direction are included in the same virtual plane I-S is a distribution of the pressing force received by the wheel running surface 42 from the ground contact surface 71 of the roller 7. Becomes uniform in the width direction. Therefore, when a crawler type traveling vehicle equipped with the elastic crawler 41 travels on a road surface including pebbles such as muddy ground or sandy ground, pebbles or the like are present between the ground contact surface 71 of the wheel 7 and the wheel traveling surface 42. If it gets caught, it becomes difficult to be eliminated, and an insect erosion phenomenon tends to occur on the wheel running surface 42 at an early stage. When worm erosion occurs, damage to the wheel running surface 42 proceeds and the life of the elastic crawler 41 is reduced.

  In order to solve such a problem that pebbles or the like are not easily removed when the ground contact surface 71 of the wheel 7 and the wheel running surface 42 are sandwiched, as shown in FIG. It has been proposed that the wheel traveling surface 52 has a (convex) shape that is convex toward the inner peripheral side in the cross section in the width direction (Patent Document 2).

JP-A-11-222168 JP 2006-111113 A

In the elastic crawler 51 proposed in Patent Document 2, the pebbles and the like placed on the wheel running surface 52 where the wheel 7 is not running (at a position deviated from the lower side of the wheel) are mountain-shaped. It escapes to the outside of the wheel running surface 52 along the inclination. Therefore, the elastic crawler 51 proposed in Patent Document 2 is less likely to cause the worm-feeding phenomenon due to the roller 7 being less likely to hit the surface of the roller crawling surface 52 with pebbles or the like placed thereon. .
When attention is paid to a part of the wheel running surface 52, the mountain-shaped top 53 is pressed by the wheel 7 immediately before reaching the lower side of the wheel 7 until the wheel 7 runs on it. And sink gradually. Therefore, even if pebbles and the like remain on the wheel running surface 52, the pebbles and the like are pushed to the outside of the wheel running surface 52 simultaneously with the sinking of the top 53.

Further, in a state in which the mountain-shaped top 53 of the wheel running surface 52 is crushed by the traveling wheel 7, the wheel running surface 52 has a mountain shape, and therefore the pressure applied from the wheel 7. The distribution does not become uniform in the width direction, and this pressure decreases as the distance from the top 53 increases to both sides in the width direction. As a result, an effect of pushing the pebbles or the like sandwiched between the ground contact surface 71 of the wheel 7 and the wheel traveling surface 52 to the outside during traveling occurs.
The elastic crawler 51 proposed in Patent Document 2 solves the problem that pebbles and the like are sandwiched between the ground contact surface 71 of the wheel 7 and the wheel traveling surface 52 as described above.

However, even in the elastic crawler 51, pebbles and the like that have entered between the top 53 and the protruding guide protrusion 54 are not completely removed to the outside, and the pebbles and the like are not removed to the outside. There is a risk of being caught between the surfaces.
In addition, the engagement hole 56 provided in the elastic crawler 51 for fitting the teeth of the drive sprocket of the crawler type traveling vehicle passes through the inner peripheral side and the outer peripheral side of the elastic crawler 51 in order to prevent passage of pebbles and the like. Instead, it may be formed as a recess having a bottom 57. In such an elastic crawler 51, pebbles and the like removed from the wheel running surface 52 inward in the width direction accumulate in the engagement holes 56. Then, the teeth of the rotating drive sprocket fit into the engagement hole 56 and press pebbles or the like against the bottom 57 of the relatively thin engagement hole 56, causing a crack or the like in the bottom 57 of the engagement hole 56. . In the elastic crawler 51 having the bottom 57 without the engagement hole 56 penetrating, this crack or the like may spread around the engagement hole 56 and the life thereof may be shortened.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a long-life elastic crawler in which the occurrence of the worm-feeding phenomenon on the wheel running surface is suppressed.

  The elastic crawler according to the present invention is an elastic crawler in which a plurality of lugs protrude on the outer peripheral side, and a plurality of cored bars having a pair of guide protrusions for guiding a wheel are embedded with a gap in the circumferential direction. In order to run the wheel, a wheel running surface that has a predetermined width on the outer side in the width direction than the pair of guide protrusions on the inner circumferential surface and makes one turn in the circumferential direction. And when the grounding side end surface of the lug is allowed to stand on a horizontal ground, the wheel running surface is formed by an inclined surface that is inclined in the width direction with respect to the ground, or An inclined surface that is inclined in the width direction with respect to the ground on the outer side in the width direction and a horizontal horizontal plane that is continuous with the inclined surface in the width direction, and is more in the width direction than the wheel running surface. The inner peripheral surface having a step between the outer peripheral surface and the outer peripheral surface The height from the ground is higher, and the inclined surface has a higher height from the ground at the inner side end than the outer side end in the width direction. It inclines at 3 degree or more and 10 degrees or less, the height difference from the said ground by the said step is 1 mm or more and 15 mm or less, and the height difference of the both ends of the said width direction in the said inclined surface is 2 mm or more.

  According to the present invention, in an elastic crawler, the occurrence of worm erosion on a wheel running surface is suppressed, and the life is increased.

FIG. 1 is a cross-sectional view of the elastic crawler in the width direction. FIG. 2 is a cross-sectional view of another elastic crawler in the width direction. FIG. 3 is a cross-sectional view of a conventional elastic crawler in the width direction. FIG. 4 is a sectional view in the width direction of a known elastic crawler. FIG. 5 is a cross-sectional view in the width direction of one form of the wheel running surface. FIG. 6 is a cross-sectional view in the width direction of another embodiment of the wheel running surface. FIG. 7 is a sectional view in the width direction of a known wheel running surface.

FIG. 1 is a cross-sectional view of the elastic crawler 1 in the width direction.
The “inner peripheral side” in the elastic crawler 1 is a side that becomes an inner peripheral side when mounted on a crawler type traveling vehicle, and is a side opposite to a side (outer peripheral side) that is grounded during traveling. The direction in which the elastic crawler 1 circulates is called “circumferential direction”, and the direction perpendicular to the circumferential direction at this time and parallel to the rotation axis of the wheel 7 of the crawler type traveling vehicle is called “width direction”. The crawler body 2, the core metal 3, the lug 4, and a pair of tensile bodies 5 and 5.

The crawler body 2 is formed in an endless belt shape by joining both ends of a thick belt rubber.
The cored bar 3 has a substantially rectangular plate shape as a whole, and is located inward of the wing parts 11 and 11 that extend inward from both ends in the longitudinal direction, and spaced from each other. A pair of guide protrusions 12 and 12 projecting from one side of the plate shape.
The guide protrusions 12 and 12 are for guiding the wheels 7 and the like so that the elastic crawler 1 does not come off from the traveling crawler type traveling vehicle.

The cored bar 3 is embedded in the crawler main body 2 at equal intervals in the circumferential direction so that the guide protrusions 12 and 12 protrude toward the inner peripheral side and the longitudinal direction thereof becomes the width direction of the crawler main body 2.
In the elastic crawler 1, an engagement hole 14 is provided between the core bars 3 adjacent to each other in the circumferential direction for inserting the teeth of the drive sprocket of the crawler type traveling vehicle.
On the outer peripheral side of the crawler main body 2, a lug 4 for gripping the ground traveling when the crawler type traveling vehicle travels projects.
The tensile body 5 is formed by arranging a plurality of tensile cords such as steel cords in a line in the width direction. Each tensile body 5, 5 is embedded in the crawler body 2 in a state where the outer peripheral side of the wing parts 11, 11 of the core metal 3 is wound over the entire circumferential direction.

Now, the crawler main body 2 is provided with the wheel running surfaces 6 and 6 having a predetermined width and rotating around in the circumferential direction outside the both guide projections 12 and 12 on the inner peripheral surface. The wheel running surface 6 is a surface on which the ground contact surface 71 of the wheel 7 runs.
Each of the wheel running surfaces 6 and 6 on both sides in the width direction is a straight line inclined in the cross section in the width direction shown in FIG. 1, and the end on the guide projections 12 and 12 side is located on the inner peripheral side with respect to the other end. ing. That is, the wheel running surface 6 is inclined so as to approach the outer peripheral surface 13 of the crawler body as it goes from the inner side in the width direction to the outer side. The inclination angle θ (referred to as “inclination angle θ”) of the wheel running surface 6 is preferably 3 degrees or more and 10 degrees or less.

Assuming that the elastic crawler 1 is straightly stretched in a belt shape, the roller running surface 6 is a flat surface over its entire length. When the outer peripheral side of the elastic crawler 1 comes in contact with the wheel running surface 6, the height from the ground is highest at the end on the guide projections 12 and 12 side and lowest at the other end.
Further, the wheel running surface 6 is continuous with the surface on the width direction end side through the step, and the height H of the step is designed to be 1 mm or more and 15 mm or less.
In the elastic crawler 1, the engagement hole 14 is formed so as to penetrate the inner peripheral side and the outer peripheral side of the elastic crawler 1, or formed so as to open to the inner peripheral side and be closed by the bottom 15 on the outer peripheral side. be able to. The elastic crawler 1 shown in FIG. 1 has an engagement hole 14 whose outer peripheral side is closed by a bottom 15. Hereinafter, the bottom 15 of the engagement hole 14 is referred to as a drive film 15.

FIG. 2 is a cross-sectional view in the width direction of another elastic crawler 1B.
The elastic crawler 1B includes a crawler body 2B, a cored bar 3, a lug 4, a pair of tensile members 5, 5 and the like. The elastic crawler 1B is the same as that in the elastic crawler 1 except for the shape of the wheel running surface 6B in the crawler main body 2B. In FIG. 2, the same parts as those in the elastic crawler 1 are denoted by the same reference numerals as those in the elastic crawler 1, and the description thereof is omitted.
The wheel running surface 6B is formed such that a predetermined width w from the end on the guide projection 12 side toward the other end is horizontal when the elastic crawler 1B is grounded. Then, the portions 21B and 21B (hereinafter, referred to as “flat portions 21B”) having a predetermined width w on the rolling wheel running surfaces 6B and 6B on both sides in the width direction are one imaginary line L in the cross section in the width direction shown in FIG. -N included. That is, the flat portions 21B and 21B on both sides have the same distance from the outer peripheral surface 13 of the crawler body, and the height from the ground is equal when the outer peripheral side of the elastic crawler 1 is in contact with the ground.

The wheel running surface 6B is inclined such that a portion outward in the width direction from the flat portion 21B approaches the outer peripheral side surface 13 of the crawler body 2B as it goes outward. This inclined portion is referred to as “inclined portion 22B”. The inclined portions 22B and 22B on both sides in the width direction have the highest height from the ground at the end on the flat portion 21B side and the lowest at the other end.
Table 1 shows the results of examining the relationship between the difference in the shape of the rolling wheel running surfaces 6, 6B, 42, and 52, the degree of worm-eating and the vibration during running.

In the elastic crawler 1 (FIG. 1), the inclination angle θ in Table 1 is an angle at which the wheel running surface 6 is inclined with respect to the horizontal plane when the contact-side end surface 16 of the lug 4 is grounded to the horizontal plane (FIG. 1). 5). Similarly, the inclination angle θ in the elastic crawler 1B (FIG. 2) is an angle at which the inclined portion 22B is inclined with respect to the horizontal plane (see FIG. 6). In the elastic crawler 51 of Comparative Example 2 (FIG. 4), the inclination angle θ is an angle at which the inclined surface 55 on the outer side in the width direction than the top 53 is inclined with respect to the horizontal plane (see FIG. 7).
Further, the height difference h is a difference in height between the lowest part and the highest part of the wheel running surfaces 6, 6B, 52 when the ground-side end face 16 of the lug 4 is grounded on a horizontal plane.

All the elastic crawlers 1, 1 </ b> B, 41, 51 in Table 1 have a horizontal width (dimension in the width direction) Wd of the wheel running surfaces 6, 6 </ b> B, 42, 52 of 30 mm. Each of the elastic crawlers 1, 1 B, 41, 51 has a step with a height H of 1 mm between the wheel running surfaces 6, 6 B, 42, 52 and the surface on the width direction end side. The height of the wheel running surfaces 6, 6B, 42, 52 from the ground is high.
The damage index in Table 1 was obtained for each of the elastic crawlers 1, 1 </ b> B, 41, and 51 having the engaging hole 14 penetrating the elastic crawler 1 and the elastic crawler 1, 41 </ b> B and 51.

The test for the damage index is carried out by running a mounted crawler-type traveling vehicle and engaging with the wheel running surfaces 6, 6B, 41, 51, around the engaging hole 14 passing therethrough, and the driving film 15. Each accumulated running time (endurance time) until damage occurred around the hole 14 was measured.
Each numerical value of the damage degree index is determined by using each measured traveling time until damage (worm eater) is recognized at each location in the elastic crawler 41 (Comparative Example 1) shown in FIG. It calculated by multiplying the numerical value which remove | divided each reference time in the driving time until the damage of each location in an example and a comparative example was recognized by 100. For example, the damage index 0.8 on the wheel running surface 6B of the second embodiment means that the running time until the wheel running surface 6B is damaged is damaged on the wheel running surface 42 of the first comparative example. It shows that it was 1.25 times the running time until it was recognized. The smaller the value of the damage degree index, the longer the accumulated traveling time until damage (worm erosion) occurs, and the higher the durability.

Further, the traveling vibration index in Table 1 is for the elastic crawlers 1, 1 </ b> B, 41, 51 having the engaging holes 14 therethrough. The running vibration index is determined by the measured value of the acceleration sensor installed on the crawler type traveling vehicle and the driver's experience by running the crawler type traveling vehicle equipped with each elastic crawler 1, 1B, 41, 51 under a certain condition. The determined value was obtained as a relative value when the value in the elastic crawler 41 (Comparative Example 1) was set to 100. The running vibration index is inversely proportional to the degree of vibration, and the smaller the value, the greater the running vibration.
From the results shown in Table 1, it can be seen that the elastic crawlers 1, 1 </ b> B have a longer durability and higher durability than the elastic crawlers 41, 51 until damage (insect erosion) occurs. On the other hand, the elastic crawlers 1, 1 </ b> B tend to have greater vibration during traveling than the elastic crawlers 41, 51.

In the elastic crawlers 1 and 1B, it is important to increase durability, and this is not a problem for a slight increase in vibration during traveling, and the decrease in traveling vibration index is 10 or less compared to the conventional elastic crawler 41. In this case, it was acceptable. Then, it can be seen from Table 1 that when the inclination angle θ is 3 degrees or more and 10 degrees or less, in the elastic crawlers 1 and 1B, the damage degree index can be lowered and the increase in vibration during traveling can be suppressed.
In the elastic crawlers 1 and 1B having the wheel running surfaces 6 and 6B having the inclination angle θ as described above, pebbles and the like riding on the wheel running surfaces 6 and 6B are excluded outward in the width direction due to the inclination, Adherence of pebbles and the like to the wheel running surfaces 6 and 6B is prevented.

The height difference h in the rolling wheel running surfaces 6 and 6B is 1.5 mm or more from Table 1, and a decrease in the damage index is observed. The height difference h is preferably 2 mm or more.
Further, the elastic crawlers 1 and 1B have a roller rolling surface 6 and 6B that is higher by forming a step having a height H of 1 mm between the surface and the surface on the width direction end side. Removal of pebbles and the like from the wheel running surfaces 6 and 6B to the outside is promoted, and the pebbles and the like are sandwiched between the wheel 7 and the wheel running surfaces 6 and 6B. Damage is prevented.
In the above-described embodiment, the configuration of the elastic crawlers 1 and 1B and the elastic crawlers 1 and 1B or the overall structure, shape, dimensions, number, material, and the like can be appropriately changed in accordance with the spirit of the present invention.

  INDUSTRIAL APPLICABILITY The present invention can be used for a traveling vehicle such as a civil engineering work machine, a construction working machine, or an agricultural working machine, and an elastic crawler attached to them.

DESCRIPTION OF SYMBOLS 1,1B Elastic crawler 3 Core metal 4 Lugs 6, 6B Rolling wheel running surface 7 Rolling wheel 12 Guide protrusion 16 (Lug) ground side end surface 21B Horizontal surface (flat part)
22B inclined surface (inclined part)
θ angle (tilt angle)

Claims (1)

A plurality of lugs projecting on the outer peripheral side, and a core bar having a pair of guide projections for guiding the rolling wheels is an elastic crawler embedded with a plurality in the circumferential direction,
In order to run the wheel, a wheel running surface that has a predetermined width on the outer side in the width direction than the pair of guide protrusions on the inner circumferential surface and makes a round in the circumferential direction is provided. And
When the grounding side end face of the lug is allowed to stand on a horizontal ground,
The wheel running surface is
All of them are formed by an inclined surface inclined in the width direction with respect to the ground, or an inclined surface inclined in the width direction with respect to the ground on the outer side in the width direction and on the inner side thereof A horizontal plane that is continuous and has a step between the outer circumferential surface and the outer peripheral surface of the wheel running surface, and the ground surface is more than the inner peripheral surface. The height from
The inclined surface has a higher height from the ground at the inner side end than the outer side end in the width direction, and is inclined at an angle of 3 degrees to 10 degrees with respect to the ground.
The height difference from the ground due to the step is 1 mm or more and 15 mm or less,
An elastic crawler, wherein a difference in height between both ends of the inclined surface in the width direction is 2 mm or more.

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