JP2004216991A - Crawler traveling gear - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a crawler traveling gear capable of traveling in grassland with soft soil with sufficient propulsion force, and suppressing roughening of a traveling track. <P>SOLUTION: On an outer peripheral surface of a rubber crawler belt 8, a long lug 15a that reaches a belt outside end and a short lug 15b that does not reach the belt outside end are disposed alternately in a belt circumferential direction, and in an open angle shape and a staggered shape in a belt forward rotating direction F. At an outer end on a top portion grounding surface S in the long lug 15a, a tilting chamfering portion M1 facing in a lateral outside direction opposite to the belt forward rotating direction F is formed. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a crawler traveling device mainly used for a tractor.
[0002]
[Prior art]
On the ground surface of the rubber crawler belt used in the crawler traveling device, propulsion lugs are formed in various patterns, for example, a long lug reaching the belt outer end and a short lug not reaching the belt outer end. Are alternately arranged in the belt circumferential direction (see Patent Literature 1), and those in which a letter-shaped lug from the center of the belt width to the outer edge of the belt is arranged in a staggered manner (see Patent Literature 2). In each case, by increasing the lug interval in the vicinity of the outer end of the crawler belt to be larger than the lug interval in the central portion of the belt width, the function of retaining the soil at the portion where the lug interval is large is increased, and the thrust is secured. The running vibration is suppressed by reducing the lug interval at the center of the belt width.
[0003]
[Patent Document 1]
JP-A-6-40361 (FIGS. 1, 8, 9, and 10)
[0004]
[Patent Document 2]
JP-A-6-329059 (FIG. 4)
[0005]
[Problems to be solved by the invention]
The lugs protruding from the grounding surface of the rubber crawler belt are generally formed with tapered front, rear, left and right side surfaces for molding and strength reasons, and are formed at the tops of the lugs. The flat grounding surface is formed in a shape that is slightly smaller than the planar shape of the entire lug.
[0006]
When traveling on a meadow with a crawler traveling device in which a crawler belt having such a lug pattern is wound, when the lug reaching the outer end of the belt is wound up and rotated along the rear wheel, the outer end corner of the lug is in the grassland. By turning upward in an arc trajectory from a state where the grass is digging into the ground, a part of the grass was scraped up with the root, and the running trace was likely to be rough. In other words, the outer end of the crawler belt is likely to bend due to the ground reaction force, and as a result, the outer end corner of the bent lug is displaced upward when it comes to the ground and elastically restored due to the release of the ground pressure. One of the pastures was sometimes jumped up due to the combined displacement with the displacement.
[0007]
The present invention has been made by paying attention to such a point, and it is possible to travel with sufficient propulsion on a meadow where the soil is soft, and it is possible to suppress the running trace from becoming rough. It is an object to provide a crawler traveling device.
[0008]
[Means for Solving the Problems]
[0009]
The crawler traveling device according to the first aspect of the present invention, on the outer peripheral surface of a rubber crawler belt, long lugs reaching the belt outer end and short lugs not reaching the belt outer end are alternately arranged in the belt circumferential direction, An inclined chamfer is formed at an outer end portion of the top grounding surface of the long lug in a direction opposite to the belt advancing rotation direction and in a laterally outward direction.
[0010]
According to the above configuration, it is possible to run with less vibration by reducing the pitch between the long lugs and the short lugs alternately arranged in the belt circumferential direction. The holding length of the soil between the adjacent long lugs is increased, and cutting (shearing) of the soil at this portion is suppressed. As a result, improvement in propulsive force and suppression of slip are achieved.
[0011]
In addition, when the crawler belt is wound up along the rear wheel when traveling forward on the pasture, the outer end portion of the long rug that cuts into the soil tends to dig up the root of the pasture, but the top contact with the long rug is difficult. Since the outer chamfered portion is formed at the outer end of the ground so as to extend rearward and outward, the digging of the root portion as described above is suppressed.
[0012]
Therefore, according to the first aspect of the present invention, it is possible to travel on a pasture with a sufficient propulsive force, and it is possible to suppress the running trace from being roughened.
[0013]
The crawler traveling device according to a second aspect of the present invention is the crawler traveling device according to the first aspect, wherein the long lug is formed from the intermediate portion of the belt width to the outer end of the belt, and the short lug is formed from the intermediate portion of the belt width to the outer end of the belt. The long lug and the short lug are arranged in a zigzag shape narrowing in the belt forward rotation direction and in a staggered manner.
[0014]
According to the above configuration, the ground contact state by the lug group is continuous in the belt circumferential direction, and the vibration when the ground contact rolling wheel rolls on the belt inner peripheral surface is reduced.
[0015]
Therefore, according to the second aspect of the present invention, the above-described effects of the first aspect of the present invention can be obtained, and a more comfortable ride can be performed.
[0016]
A crawler traveling device according to a third aspect of the present invention is the crawler traveling device according to the second aspect, wherein the outer end portions of the long lugs arranged in a C shape are bent so as to be substantially orthogonal to the belt circumferential direction. is there.
[0017]
According to the above configuration, the soil holding function between the long lugs adjacent to each other near the outer end of the belt is further enhanced.
[0018]
Therefore, according to the third aspect of the invention, the above-described effect of the second aspect of the invention is provided, and the propulsion ability on a soft pasture is further improved.
[0019]
According to a fourth aspect of the present invention, in the crawler traveling device according to the second or third aspect, an inclined chamfer is formed at a front end portion of the long lug and the short lug in a belt forward rotation direction. It has been done.
[0020]
According to the above configuration, when the crawler belt rotates forward, the ground starts from the inclined chamfered portion at the front end of the rug, so that the crawling belt smoothly enters the pasture.
[0021]
Therefore, according to the fourth aspect of the present invention, the above-described effects of the second or third aspect of the present invention are provided, and the present invention is more effective in suppressing the roughness of the running trace.
[0022]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 illustrates a tractor equipped with a crawler traveling device according to the present invention. This tractor is mainly used for grass harvesting work and the like, and has a structure in which crawler traveling devices 2 are mounted instead of the left and right rear wheels of the four-wheel drive type tractor main unit 1, respectively. Although not shown, a working device such as a grass cutting device or a grass collecting device is connected to the tractor machine 1.
[0023]
In the crawler traveling device 2, a rubber crawler belt 8 is wound around a driving wheel 3, a front end tension wheel 4, a rear wheel 5, a group of ground wheels 6 and a guide wheel 7 in a triangular shape. The drive wheel 3 is connected to a drive shaft 10 mounted on a rear axle case 9 of the tractor main body 1, and further includes a tension wheel 4, a rear end wheel 5, a group of ground wheels 6, and The guide wheel 7 is mounted and supported on a track frame 11 that is swingably connected to a rear axle case 9 about a horizontal fulcrum X.
[0024]
Driving projections 12 project at a constant pitch in the circumferential direction at an intermediate portion in the width direction of the inner peripheral surface of the crawler belt 8, and driving pins 13 extend laterally at a constant pitch in the circumferential direction on the outer peripheral portion of the driving wheel 3. The crawler belt 8 is rotated forward or backward by the drive wheel 13 being driven forward or backward by engaging the drive pin 13 with the drive projection 12.
[0025]
On the outer peripheral surface of the crawler belt 8, propulsion lugs 15 are protruded in a pattern shown in FIG. The propulsion lug 15 includes a long lug 15a extending from the center of the belt width to the outer end of the belt and a short lug 15b extending from the center of the belt width to the outer end of the belt. They are arranged in a zigzag pattern that becomes narrower in the rotation direction F. Further, the vicinity of the outer end of the long lug 15a, that is, the long lug portion extending outward from the short lug 15b is bent so as to be substantially perpendicular to the belt circumferential direction.
[0026]
In this way, the long lugs 15a and the short lugs 15b are alternately arranged in the circumferential direction of the belt, so that the soil holding length between the long lugs 15a adjacent to each other in the vicinity of the outer end of the belt increases. Cutting (shearing) of the soil at the leverage portion is suppressed, and as a result, the driving force is improved and the slip is suppressed. In particular, since the long lug portion extending outward from the short lug 15b is bent so as to be substantially perpendicular to the belt circumferential direction, the long lug 15a is held between the long lugs 15a adjacent to each other near the outer end of the belt. The soil thus soiled is less likely to collapse, and the soil holding function near the outer end of the long lug 15a is further enhanced. Further, the long lugs 15a and the short lugs 15b are arranged in a V-shape narrowing in the belt forward rotation direction F and are arranged in a staggered manner, so that the lugs are continuously contacted with the ground. Less traveling is possible. Further, even when soil is attached between the lugs when the crawler belt 8 is wound up and rotated along the rear rolling wheel 5 at the rear end of the traveling device during forward running, the lugs are in the opposite direction to the belt forward rotating direction. Since it spreads in a V-shape, the adhered soil is easily dropped off from between the lugs, and the rotation of the soil can be reduced.
[0027]
Here, an inclined chamfered portion M2 directed to the belt forward rotation direction F is formed at the inner end portion of the long lug 15a and the short lug 15b, and when traveling forward on the meadow, the inside of the long lug 15a and the short lug 15b is formed. When the end portion starts to contact the ground, the lug 15 smoothly contacts the ground at the inner end corner without going over the soil.
[0028]
An inclined chamfered portion M1 is formed at the outer end portion of the long lug 15a at the outer end portion of the top grounding surface S so as to extend in the C-shaped spreading direction. The formation of the slope chamfer M1 prevents the root of the grass from being dug up at the corner of the outer end portion of the long rug 15 that has penetrated the soil when it is rolled up along the ground 5.
[0029]
The tension wheel 4, the rear end wheel 5, the group of ground contact wheels 6, and the guide wheel 7 are configured as a so-called outer wheel type rolling wheel in which a pair of left and right wheels are arranged at regular intervals. The right and left wheels engage with the driving projections 12 to restrict the crawler belt 8 from moving left and right.
[0030]
Here, as shown in FIGS. 5 and 6, the left and right side surfaces of the drive projection 12 of the crawler belt 8 are divided into a lower half 12a and an upper half 12b. On the other hand, the upright inclination angle β of the upper half 12b is set small. An inclined guide surface c is formed near the outer periphery of the inward side surface of the ground wheel 6 opposite to the left and right side surfaces of the driving projection 12 in parallel with the side surface of the lower half portion 12a of the driving projection 12. . Then, in a state where the inner circumference of the crawler belt 8 is correctly contacted with the outer circumference of the ground roller 6, the inclined guide surface c is opposed to the side surface of the lower half 12a in a range lower than the height of the lower half 12a. Is set. Further, the curvature curvature r1 of the upright inner corner portion of the drive projection 12 and the curvature curvature r2 of the outer peripheral end of the inclined guide surface c in the ground contact wheel 6 are set to be the same or substantially the same. Although not shown, the wheels (tension wheel 4, rear wheel 5 and guide wheel 7) other than the ground wheel 6 also have the same inclined guide surface as the above specification on the inward side surface. ing.
[0031]
When the driving protrusion 12 and the ground contact wheel 6 are configured as described above, when the crawler belt 8 receives a thrust force and slides sideways during traveling on flat ground, as shown by a solid line in FIG. The inclined guide surface c of the ground contact wheel 6 comes into contact with the side surface of the lower half portion 12a of the driving projection 12 so that the outer peripheral end of the inclined guide surface c comes into close contact with the standing inner corner of the wheel 12. Since the area is sufficiently smaller than the entire area of the side surface of the driving projection 12 and the thrust force generated during traveling on flat ground is not so large, the side surface of the lower half 12a of the driving projection 12 and the inclined guide of the grounding wheel 6 The frictional heat generated at the contact portion with the surface c is relatively small, and the strength of the driving projection 12 does not decrease due to the frictional heat even at a high speed.
[0032]
In addition, in the case of turning the vehicle, traveling on an inclined ground, or plowing work in which one wheel is dropped into a plow mark and travels in a laterally inclined posture, the ground contact wheel 6 is shifted relatively upward with respect to the crawler belt 8. However, since the inclined guide surface c of the ground contact wheel 6 is lower than the lower half portion 12a of the driving projection 12, the relative vertical movement to the height indicated by the phantom line in FIG. There is no change in the contact area between the lower half portion 12a of the projection 12 and the inclined guide surface c of the grounding wheel 6, and the lower half portion 12a having a large thickness in the lateral direction and high rigidity reliably supports the thrust load.
[0033]
If contour running (inclined running), sharp turning, etc. are performed, the crawler belt 8 may be deformed in the lateral direction and the arrangement of the driving projections 12 may be shifted. As the wheel 6 is engaged, a phenomenon (galling) that the grounding wheel 6 rides on the upper end corner of the driving projection 12 that is displaced and bites tends to occur. Also, when the crawler traveling device 2 moves in and out of the plow by the plow, when the ground contact wheel 6 floats with respect to the crawler belt 8 and engages with the next driving projection 12, the driving projection 12 Is likely to occur due to the misalignment. Further, even when one end of the crawler belt 8 gets over a relatively small obstacle such as a stone, a part of the crawler belt 8 is pushed up and deformed, thereby causing a displacement of the driving projection 12, resulting in a displacement. When the grounding wheel 6 engages with the driving projection 12, the galling may occur. However, as described above, since the upper half portion 12b of the driving projection 12 is particularly tapered, the driving projection 12 easily slides between the left and right wheels of the ground contact rolling wheel 6, and The ground contact wheel 6 smoothly guides and engages with the driving projection 12 which is displaced without occurrence of "scraping".
[0034]
In addition, the tapered shape having a small rising inclination angle β is formed only by the upper half portion 12b, and the lower half portion 12a has a large rising inclination angle α and a large thickness in the left-right direction. The strength of the projection 12 is high.
[0035]
[Another embodiment]
(1) In the above embodiment, the case where the driving protrusions 12 provided on the inner peripheral surface of the crawler belt 8 are engaged with the driving wheels 3 to rotate the crawler belt 8 is described. A driving hole may be formed at a constant pitch in the circumferential direction at the intermediate portion, and the pawl of the sprocket-shaped driving wheel may be engaged with the driving hole and driven to rotate.
[0036]
(2) The present invention employs a lug pattern in which the long lugs 15a and the short lugs 15b are arranged in parallel in the left-right direction (see Patent Literature 1). It is also applicable to a lug pattern in which short lug portions are arranged at a small pitch in the portion and long lug portions reaching the belt side end portion are formed at a large pitch on the outer side of the belt (see Patent Document 2). .
[Brief description of the drawings]
FIG. 1 is an overall side view of an agricultural tractor. FIG. 2 is a side view of a crawler traveling device. FIG. 3 is a vertical front view of a crawler traveling device. FIG. 4 is a vertical front view showing a driving unit of the crawler traveling device. FIG. 6 is an enlarged front view showing a belt guide portion provided by a ground contact wheel during traveling on level ground. FIG. 7 is an enlarged front view showing a belt guide portion provided by a contact roller during traveling on level ground. FIG. 8 is a plan view of a lug pattern. FIG. 9 is a cross-sectional view taken along a line AA in FIG. 8. FIG. 10 is a perspective view showing a part of a crawler belt.
8 Crawler belt 15a Long lug 15b Short lug F Belt advance rotation direction M1 Inclined chamfer M2 Inclined chamfer S Top contact surface

Claims (4)

On the outer peripheral surface of the rubber crawler belt, a long lug reaching the outer end of the belt and a short lug not reaching the outer end of the belt are alternately arranged in the circumferential direction of the belt. A crawler traveling device, wherein a slanted chamfer is formed in a direction opposite to the belt forward rotation direction toward a laterally outward direction. The long lug is formed from the intermediate portion of the belt width to the outer end of the belt, and the short lug is formed from the intermediate portion of the belt width to just before the outer end of the belt. 2. The crawler travel device according to claim 1, wherein the crawler travel device is arranged in a zigzag shape that narrows in a movement direction. The crawler traveling device according to claim 2, wherein an outer end portion of the long lugs arranged in a C shape is bent so as to be substantially perpendicular to a belt circumferential direction. The crawler travel device according to claim 2 or 3, wherein an inclined chamfered portion directed toward the bell forward rotation direction is formed at a front end portion of the long lug and the short lug in the belt forward rotation direction.

Images