JP3883129B2 - Ladder-type crawler - Google Patents

Description

  The present invention relates to a ladder-type crawler.

Ladder type in which lugs for generating traction force are formed in a so-called ladder shape, suitable for running on soft ground such as wet fields among elastic crawlers made of elastic materials such as rubber formed in an endless belt shape A crawler is known (see, for example, Patent Document 1).
FIG. 9 is an outer peripheral side plan view showing an example of a conventional ladder type crawler (hereinafter referred to as “conventional example 1”), and FIG. 10 is another example of a conventional ladder type crawler (hereinafter referred to as “conventional example 2”). FIG. The ladder-type crawler of Conventional Example 1 includes a lug 3a and a belt extending toward one end side in the width direction of the crawler main body 1 embedded with a core metal 2 formed in an endless belt shape. The lugs 3b extending toward the other end in the width direction are alternately protruded integrally at a predetermined interval along the longitudinal direction of the band, and the same direction is provided on both sides of the crawler body 1 in the width direction. The crawler blade 5 having a notch recess symmetrical between the lugs 3a and 3a or between the lugs 3b and 3b is integrally formed. The ladder-type crawler of Conventional Example 2 is not extended with lugs 3c extending toward both sides in the band width direction on the outer peripheral side (ground surface side) of the crawler body 1 embedded with the cored bar 2 formed in an endless band shape. The protruding lugs 3d are alternately projected integrally at a predetermined interval along the longitudinal direction of the belt, and between the lugs 3c, 3c on one side (the right side in FIG. 10) of the crawler body 1 The crawler blade 5 having a symmetric notch recess is integrally formed.

Japanese Patent Laid-Open No. 9-58538 (2nd page, FIG. 1)

  In general, including the ladder-type crawlers of the conventional examples 1 and 2 and the ladder-type crawler disclosed in Patent Document 1, in the ladder-type crawler, in order to improve the running performance in soft ground, the traction force is improved and the contact surface pressure is dispersed. It has become a major technical issue to balance. In other words, the improvement in traction force can be easily achieved if the shear area is increased because the penetration into the soft ground is improved. The problem that it becomes pressure and becomes easy to sink in soft ground will arise. On the other hand, the dispersion of the contact surface pressure can be easily achieved by increasing the contact area, but if the contact area is increased too much, the penetration into soft ground will deteriorate and the necessary traction force will not be secured. Problems arise. Thus, the improvement of traction force and the dispersion of contact surface pressure are in a trade-off relationship, and it is important how to balance the two to improve the running ability in soft ground.

  The present invention has been made in view of such circumstances, and an object thereof is to provide a ladder-type crawler having excellent soft ground running ability.

  The present inventor has conducted intensive research to balance the traction force and the contact surface pressure to improve the running performance in soft ground. In this process, when the ground contact state of the ladder type crawler during traveling is observed, the leading side of the crawler traveling direction in the notch recess of the crawler blade formed between the lugs contributes greatly to the traction force of the ladder type crawler during traveling. Part (H in FIGS. 9 and 10), which greatly contributes to the contact surface pressure of the ladder-type crawler is a rearward side part in the crawler traveling direction in the notch recess of the crawler blade formed between the lugs (FIG. 9, Attention was paid to the point 10). Therefore, as a result of various investigations on the notch recesses of the crawler blades, if the asymmetric notch recesses of a predetermined size are positioned according to the crawler traveling direction, the traction force and the contact surface pressure are balanced and the soft ground As a result, the present invention was completed.

  That is, the first ladder-type crawler of the present invention is formed integrally with the crawler body made of an elastic material formed in an endless belt shape and the grounding surface side of the crawler body, and extends to one end side in the belt width direction. A lug group having a lug pattern formed by alternately arranging lugs having an extending portion and lugs not having the extending portion in the longitudinal direction of the belt, and a band width corresponding to the extending portion of the lug in the crawler body A ladder-type crawler having a crawler blade integrally formed in a range of directions, and an extension side end portion is formed in the same direction at one end edge in the band width direction of the crawler blade and adjacent lugs Asymmetrical cutout recesses that are biased toward one side in the longitudinal direction of the belt satisfying the following formulas (1) and (2) are formed, and the cutout recesses of each asymmetric shape are Arranged in the same direction in the longitudinal direction of the band And wherein the are.

(2P−L) / 10 <A <(2P−L) / 2 (1)
[In formula (1), A is the distance from the center position of the deepest part of the notch recess of the crawler blade to the center position of the lug, P is the distance between the centers of adjacent lugs, and L is the extension of the lugs This is the length in the width direction at the side end. ]
(2P−L) / 10 <F <(2P−L) / 2 (2)
[In Formula (2), F is the depth from the lug surface to the center position of the deepest part of the notch recess of the crawler blade, P is the distance between the centers of adjacent lugs, and L is the lug extension side It is the length in the width direction at the end. ]

  According to the first ladder-type crawler having the above configuration, the notch recesses of the crawler blades between the lugs extending in the same direction are formed in an asymmetric shape having a predetermined dimension, and the notch recesses of each asymmetric shape are formed in the longitudinal direction of the belt. Therefore, the first arrival side portion in the crawler traveling direction has a gentle shape and the rear arrival side portion has a steep shape. For this reason, the contact surface pressure is distributed by the gentle shape of the first landing part, and the traction force is improved by the steep shape of the rear arrival part. As a result, the contact surface pressure and the traction force are more highly balanced. Can be made. Therefore, compared with the conventional ladder type crawler, the running performance in soft ground is very high.

  In the first ladder type crawler having the above-described configuration, the notch recesses of the crawler blades may be formed on both sides in the band width direction, and the notch recesses of the crawler blades may be on one side in the band width direction. It can be set as the formed structure.

  The second ladder-type crawler of the present invention is formed of an elastic material crawler body formed in an endless belt shape, integrally formed on the grounding surface side of the crawler body, and extended to one end side in the belt width direction. A lug group having a lug pattern formed by alternately arranging lugs having portions and lugs not having the extending portions in the longitudinal direction of the belt, and a range in the width direction corresponding to the extending portions of the lugs in the crawler body And a crawler blade formed integrally with the crawler blade, wherein one end edge in the width direction of the crawler blade is formed in the same direction with a gap between adjacent lugs. An asymmetrical cutout recess that is connected and is biased to one side in the longitudinal direction of the belt that satisfies the above formulas (1) and (2) is formed, and on one side or both sides of the crawler body in the width direction , On one side of the belt longitudinal direction Notched recess Tsu asymmetrical shape and the cutout recess of asymmetric shape biased to the opposite side thereof, characterized in that it is arranged alternately in the belt longitudinal direction.

  According to the second ladder-type crawler having the above configuration, the notch recesses of the crawler blades between the lugs extending in the same direction are formed in an asymmetric shape having a predetermined dimension, and the asymmetric shape is biased toward one side in the longitudinal direction of the belt. Notch recesses and asymmetrical notch portions that are biased to the opposite side are alternately arranged in the longitudinal direction of the belt, so that not only in one direction but also in both directions (forward and backward), contact with traction force The ground pressure is more highly balanced, and the running ability in soft ground becomes high.

  The third ladder-type crawler of the present invention is formed integrally with the crawler body made of an elastic material formed in an endless belt shape and the grounding surface side of the crawler body, and extends to one end side in the belt width direction. A lug group having a lug pattern formed by alternately arranging lugs having portions and lugs not having the extending portions in the longitudinal direction of the belt, and a range in the width direction corresponding to the extending portions of the lugs in the crawler body And a crawler blade formed integrally with the crawler blade, wherein one end edge in the width direction of the crawler blade is formed in the same direction with a gap between adjacent lugs. An asymmetrical cut-out recess is formed which is connected and is biased toward one side in the longitudinal direction of the belt that satisfies the above formulas (1) and (2), and on the one side in the width direction of the crawler body , Each asymmetrical notch recess Are arranged in the same direction in the longitudinal direction of the band, and on the other side in the band width direction of the crawler body, the notch recesses of each asymmetric shape are arranged in the direction opposite to the notch recesses on the one side. It is characterized by that.

  According to the third ladder-type crawler having the above configuration, the notch recess of the crawler blade between the lugs extending in the same direction is formed in an asymmetric shape having a predetermined dimension, and on one side of the crawler body in the band width direction. The asymmetrical cutout recesses are arranged in the same direction in the longitudinal direction of the band, and the asymmetrical cutout recesses are defined as the cutout recesses on the one side on the other side in the band width direction of the crawler body. Since they are arranged in the opposite direction, the tractive force and the contact surface pressure are more highly balanced with respect to not only one direction but also two-way progress (forward, reverse), and the running ability in soft ground becomes high.

  According to the present invention, the crawler blade is formed with the asymmetric cutout recess having a specific size, and the asymmetric cutout recess is positioned corresponding to the crawler traveling direction. The improvement and the dispersion of the surface pressure on the contact surface are balanced, and a ladder-type crawler excellent in running performance in soft ground can be provided.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
(First embodiment)
FIG. 1 is a plan view of the outer peripheral side of a ladder crawler according to a first embodiment of the present invention, and FIG. 2 is a sectional view taken along line XX. The ladder-type crawler K1 according to the present embodiment is used by being wound around a driving wheel of an infinite traveling device such as an agricultural machine or a construction machine, a wheel such as a driven wheel, and an endless crawler body 11; A core metal 12 and a tension member 14 embedded in the crawler main body 11, lugs 13a and 13b for generating traction force integrally projecting on the grounding surface side (outer peripheral surface side) of the crawler main body 11, The crawler body 11 includes crawler blades 15 integrally formed on both sides in the band width direction.

  The crawler main body 11 is formed in an endless belt shape using an elastic material such as rubber or synthetic resin that exhibits elasticity in consideration of low noise, good riding comfort, high road surface protection, and the like. A plurality of metal cores 12 are embedded in the crawler body 11 in order to increase the strength and grounding support of the ladder crawler K1. More specifically, the plurality of core bars 12 are formed of a rigid material such as metal or reinforced synthetic resin into a rod shape having a protrusion at the center, for example. The cored bars 12 are embedded in parallel at equal intervals in the longitudinal direction of the band (the circumferential direction of the ladder crawler K1). In addition, on the lower side (grounding surface side) of each cored bar 12, tensile bodies 14 made of a plurality of steel cords and the like are arranged in parallel in the band width direction at predetermined intervals along the band longitudinal direction of the crawler body 11. Embedded to increase the tensile strength of the ladder crawler K1 in the longitudinal direction of the belt.

  A plurality of lugs 13a and 13b extending in a zigzag manner in the band width direction are integrally projected in parallel in the longitudinal direction of the band on the outer peripheral side (grounding surface side) of the crawler body 11. In detail, each lug 13a of the lug group is formed to extend zigzag on one end side in the band width direction (left side in FIG. 1), and each lug 13b is formed on the other end side in the band width direction (FIG. 1). In the right side), it is formed to extend zigzag. Each lug 13a, 13b is formed with one lug notch 31 at the approximate center thereof. Further, considering the appearance improvement and mud escape, etc., it is formed to extend in a zigzag so as to incline toward the lug notch 31 or the longitudinal ends of the lugs 13a and 13b. In addition, each lug 13a and each lug 13b are arrange | positioned alternately along a strip | belt longitudinal direction, and it is formed so that it may arrange | position with the same pitch so that it may be located directly under the some metal core 12. FIG.

  On both sides of the crawler body 11 in the band width direction, crawler blades 15 are integrally formed in the band width direction range corresponding to the extending portions of the lugs 13a and 13b. One end edge of the crawler blade 15 in the width direction (left side in FIG. 1) is connected to the extended end portions 23a of the adjacent lugs 13a, and is cut in a predetermined shape cut out toward the non-grounding surface side. A notch recess 15a is formed. On the other hand, the other end edge in the width direction of the crawler blade 15 (the right side in FIG. 1) is connected to the extended side ends 23b of the adjacent lugs 13b, and is cut out toward the non-ground surface side. A notch recess 15a is formed.

  And the notch recessed part 15a of the crawler blade 15 has a longitudinal direction distance A from the center position of the deepest part (the part on the most non-contact surface side) to the center position of the lug satisfies the following formula (1), The depth F from the center position of the deepest part (the part closest to the non-grounding surface) to the lug surface is formed so as to satisfy the following formula (2). In both formulas, P is the center-to-center distance between adjacent lugs, and L is the length in the width direction at the end of the lug on the extension side.

(2P−L) / 10 <A <(2P−L) / 2 (1)
(2P−L) / 10 <F <(2P−L) / 2 (2)

That is, the notch recess 15a between the adjacent lugs 13a, 13a or between the lugs 13b, 13b of the crawler blade 15 is prevented from having a symmetrical shape at the center, and is asymmetric with a predetermined size biased to one side in the belt longitudinal direction. It is in shape.
The asymmetric notch recess 15a as described above is positioned corresponding to the traveling direction of the crawler. Specifically, in any of the crawler blades 15 on both sides in the width direction of the crawler main body 11, each notch recess 15a has a gentle shape in the first landing side portion H in the crawler traveling direction (upward in FIG. 1), Thereafter, the wear side portion J is positioned so as to have a steep shape. As a result, the first arrival side portion H has a larger ground contact area than the rear arrival side portion J, so that the contact surface pressure can be dispersed, and the rear arrival side portion J has a steep shape. Improvements can be made.

  The ladder-type crawler K1 according to the present embodiment configured as described above has a notch recess 15a between the lugs 13a, 13a or the crawler blades 15 between the lugs 13b, 13b extending in the same direction. Since the asymmetric cutout recess 15a is positioned corresponding to the crawler traveling direction, the traction force and the contact surface pressure are more highly balanced, and excellent soft running performance is exhibited. be able to. More specifically, when driving on soft ground, the steep shape located at the rear landing side portion J of the notch recess 15a makes it easy to bite into the soft ground, and a large traction force can be obtained. On the other hand, the gentle shape of the notched portion 15a located on the first landing side portion H increases the ground contact area to the soft ground, and the ground contact pressure can be dispersed. That is, a conventional ladder-type crawler is provided by causing the first landing side portion H of the notch recess 15a to play a role of dispersing the contact surface pressure and the rear landing side portion J of the notch recess 15a to play a role of improving traction. Compared to the above, the traction force and the contact surface pressure are more highly balanced, and as a result, excellent soft ground running ability can be exhibited. Further, in the ladder-type crawler K1 of the present embodiment, since the rear arrival side portion J of the notch recess 15a is all a steep surface, it is particularly excellent in turning performance and straight running performance because it is particularly difficult to insert. Has the advantage. Further, since the amount of rubber used is reduced by the notch recess 15a, there is an advantage that fuel efficiency can be improved due to weight reduction and bending rigidity reduction.

(Second Embodiment)
FIG. 3 is an outer peripheral side plan view showing a ladder-type crawler according to the second embodiment of the present invention. The ladder-type crawler K2 according to the present embodiment forms an asymmetric cutout recess 15a that satisfies the above formulas (1) and (2) only on one side in the band width direction as compared with the first embodiment. It is different in point. More specifically, an asymmetrical notch recess 15a having a predetermined dimension is formed only on one side in the band width direction (left side in FIG. 3), and a gentle shape is formed on the first arrival side portion H of the notch recess 15a, and the subsequent arrival side portion J The ground contact area of the first arrival side portion H is made larger than the ground contact area of the rear arrival side portion J. Even in such a configuration, as in the first embodiment, the traction force and the contact surface pressure are more highly balanced than in the conventional ladder type crawler, and excellent soft running ability can be exhibited. it can. Further, in the ladder-type crawler K2 of this embodiment, the asymmetric cutout recess 15a is formed only on one side in the band width direction, which is advantageous in terms of manufacturing cost.

(Third embodiment)
FIG. 4 is an outer peripheral side plan view showing a ladder type crawler according to the third embodiment of the present invention. Compared with the first embodiment, the ladder-type crawler K3 according to the present embodiment includes lugs 13c extending on both sides in the band width direction and lugs 13d not extending on both sides in the band width direction along the band longitudinal direction. The difference is that they are arranged alternately. And the asymmetric notch recessed part 15a which satisfy | fills said Formula (1) and (2) is formed with respect to the crawler blade 15 in the width direction both sides between adjacent lugs 13c, and the first arrival side part of the notch recessed part 15a A gentle shape in H and a steep shape in the subsequent arrival side portion J are formed so that the ground contact area of the first arrival side portion H is larger than the ground contact area of the rear arrival side portion J. Even in such a configuration, as in the first embodiment, the traction force and the contact surface pressure are more highly balanced than in the conventional ladder type crawler, and excellent soft running ability can be exhibited. it can.

(Fourth embodiment)
FIG. 5 is an outer peripheral side plan view showing a ladder type crawler according to the fourth embodiment of the present invention. The ladder-type crawler K4 according to the present embodiment is arranged by alternately replacing the asymmetric cutout recesses 15a satisfying the above formulas (1) and (2) along the band longitudinal direction as compared with the first embodiment. It is different in the point that it did. Specifically, on one side in the band width direction (right side in FIG. 5), a gentle shape is formed in the first arrival side portion H1 in the crawler traveling direction (upper side in FIG. 5) in the notch recess 15a, and a sharp shape is formed in the subsequent arrival side portion J1. The asymmetric notch recess 15a adjacent to the asymmetrical notch recess 15a in the longitudinal direction of the band is formed to have a steep shape in the first arrival side portion H and a gentle shape in the subsequent arrival side portion J2. The asymmetric cutout recesses 15a adjacent to each other in the longitudinal direction of the belt are formed in different directions. Similarly, an asymmetric cutout recess 15a is formed on the opposite side in the width direction (left side in FIG. 5). Even in such a configuration, as in the first embodiment, the traction force and the contact surface pressure are more highly balanced than in the conventional ladder type crawler, and excellent soft running ability can be exhibited. it can. Further, the ladder-type crawler K4 of this embodiment is formed so that the asymmetric cutout recesses 15a are formed in different directions along the longitudinal direction of the belt on both sides in the width direction of the belt. With respect to the progress in the vertical direction in FIG. 5, there is an advantage that the soft ground running property is not greatly different and the mounting direction property can be eliminated.

  In the fourth embodiment described above, the lugs adjacent to each other in the longitudinal direction of the belt are alternately extended toward one end in the different width direction. Of course, the same effect can be obtained even in the case of a group of lugs in which lugs extended toward the side and non-extending lugs are alternately arranged.

(Fifth embodiment)
FIG. 6 is an outer peripheral side plan view showing a ladder type crawler according to a fifth embodiment of the present invention. The ladder-type crawler K5 according to the present embodiment has an asymmetric cutout recess 15a that satisfies the above formulas (1) and (2) as compared to the first embodiment. It differs in that it is formed differently. Specifically, on one end side in the band width direction (left side in FIG. 6), the first arrival side portion H3 in the crawler traveling direction (upper side in FIG. 6) has a gentle shape and the subsequent arrival side portion J3 has a steep shape. Asymmetric cutout recesses 15a are formed so as to be aligned in the longitudinal direction of the band, and the other end side in the band width direction (the right side in FIG. 6) has a steep shape on the first arrival side portion H4 in the crawler traveling direction, Asymmetrical cutout recesses 15a that have a gentle shape at J4 are formed so as to be aligned in the longitudinal direction of the band. Even in such a configuration, as in the first embodiment, the traction force and the contact surface pressure are balanced, and excellent soft ground running performance can be exhibited. In the present embodiment, since the asymmetric cutout recesses 15a are arranged so as to be different on both sides in the band width direction, there is a large difference in the soft ground running property with respect to traveling in both directions (vertical direction in FIG. 6). In addition, there is an advantage that the mounting directionality can be eliminated. Further, as compared with the fourth embodiment, since the same asymmetric cutout recess 15a is formed on one side in the band width direction, there is an advantage that it is easy to manufacture.

  In the fifth embodiment, the lugs adjacent to each other in the longitudinal direction of the belt are alternately extended toward one end in the different width direction. Of course, the same effect can be obtained even in the case of a group of lugs in which lugs extended toward the side and non-extending lugs are alternately arranged.

  The present invention is not limited to the above embodiments. For example, as shown in FIGS. 7A to 7C and FIGS. 8A and 8B, the lugs 13a, 13b, 13c, and 13d may be formed in a straight line. In addition, the shape of the crawler blade may be changed as appropriate without departing from the object of the present invention. Furthermore, sprocket holes may be formed in the crawler body, the shape and presence of the core bar, the material of the tensile body, etc. may be changed as appropriate, and reinforcing fibers etc. may be embedded inside the crawler body. It may be.

It is an outer peripheral side top view which shows the ladder type crawler which concerns on the 1st Embodiment of this invention. It is XX sectional drawing of the ladder type crawler shown in FIG. It is an outer peripheral side top view which shows the ladder type crawler which concerns on the 2nd Embodiment of this invention. It is an outer peripheral side top view which shows the ladder type crawler which concerns on the 3rd Embodiment of this invention. It is an outer peripheral side top view which shows the ladder type crawler which concerns on the 4th Embodiment of this invention. It is an outer peripheral side top view which shows the ladder type crawler which concerns on the 5th Embodiment of this invention. It is an outer peripheral side top view which shows the modification of the ladder type crawler of this invention. It is an outer peripheral side top view which shows the modification of the ladder type crawler of this invention. It is an outer peripheral side top view which shows an example of the conventional ladder type crawler. It is an outer peripheral side top view which shows the other example of the conventional ladder type crawler.

Explanation of symbols

11 Crawler Body 12 Core Bar 13a, 13b Lug 14 Tensile Body 15 Crawler Blade 15a Notch Recess 23a, 23b Extension Side End 31 Lug Notch K1 Ladder Type Crawler H First Arrival Side J Last Arrival Side

Claims (5)

A crawler main body made of an elastic material formed in an endless belt shape, and a lug that is integrally formed on the grounding surface side of the crawler main body and has an extended portion toward one end side in the belt width direction. A lug group having a lug pattern in which the lugs are not arranged alternately in the longitudinal direction of the belt, and a crawler blade integrally formed in the width direction range corresponding to the extending portion of the lug in the crawler body. A ladder-type crawler,
The one end edge in the band width direction of the crawler blade has an extension side end formed in the same direction, connecting adjacent lugs, and satisfying the following formula (1) and formula (2). An asymmetrical cutout recess that is biased to one side is formed,
And the ladder type crawler characterized by notch recessed part of each asymmetrical shape being arranged in the same direction in the strip | belt longitudinal direction.
(2P−L) / 10 <A <(2P−L) / 2 (1)
[In formula (1), A is the distance from the center position of the deepest part of the notch recess of the crawler blade to the center position of the lug, P is the distance between the centers of adjacent lugs, and L is the extension of the lugs This is the length in the width direction at the side end. ]
(2P−L) / 10 <F <(2P−L) / 2 (2)
[In Formula (2), F is the depth from the lug surface to the center position of the deepest part of the notch recess of the crawler blade, P is the distance between the centers of adjacent lugs, and L is the lug extension side It is the length in the width direction at the end. ]   The ladder-type crawler according to claim 1, wherein the cutout recesses of the crawler blade are formed on both sides in the band width direction.   The ladder-type crawler according to claim 1, wherein the notch recess of the crawler blade is formed on one side in the band width direction. A crawler main body made of an elastic material formed in an endless belt shape, and a lug that is integrally formed on the grounding surface side of the crawler main body and has an extended portion toward one end side in the belt width direction. A lug group having a lug pattern in which the lugs are not arranged alternately in the longitudinal direction of the belt, and a crawler blade integrally formed in the width direction range corresponding to the extending portion of the lug in the crawler body. A ladder-type crawler,
The one end edge in the band width direction of the crawler blade has an extension side end formed in the same direction, connecting adjacent lugs, and satisfying the following formula (1) and formula (2). An asymmetrical cutout recess that is biased to one side is formed,
In addition, on one side or both sides of the crawler body in the width direction of the crawler, an asymmetrical cutout concave portion biased to one side in the longitudinal direction of the belt and an asymmetrical cutout recess portion biased to the opposite side are alternately arranged in the longitudinal direction of the belt. Ladder type crawler characterized by being.
(2P−L) / 10 <A <(2P−L) / 2 (1)
[In formula (1), A is the distance from the center position of the deepest part of the notch recess of the crawler blade to the center position of the lug, P is the distance between the centers of adjacent lugs, and L is the extension of the lugs This is the length in the width direction at the side end. ]
(2P−L) / 10 <F <(2P−L) / 2 (2)
[In Formula (2), F is the depth from the lug surface to the center position of the deepest part of the notch recess of the crawler blade, P is the distance between the centers of adjacent lugs, and L is the lug extension side It is the length in the width direction at the end. ] A crawler main body made of an elastic material formed in an endless belt shape, and a lug that is integrally formed on the grounding surface side of the crawler main body and has an extended portion toward one end side in the belt width direction. A lug group having a lug pattern in which the lugs are not arranged alternately in the longitudinal direction of the belt, and a crawler blade integrally formed in the width direction range corresponding to the extending portion of the lug in the crawler body. A ladder-type crawler,
The one end edge in the band width direction of the crawler blade has an extension side end formed in the same direction, connecting adjacent lugs, and satisfying the following formula (1) and formula (2). An asymmetrical cutout recess that is biased to one side is formed,
In addition, on one side of the crawler body in the band width direction, the asymmetrical cutout recesses are arranged in the same direction in the band longitudinal direction, and on the other side of the crawler body in the band width direction, The ladder-type crawler, wherein the notch recesses are arranged in a direction opposite to the notch recess on the one side.
(2P−L) / 10 <A <(2P−L) / 2 (1)
[In formula (1), A is the distance from the center position of the deepest part of the notch recess of the crawler blade to the center position of the lug, P is the distance between the centers of adjacent lugs, and L is the extension of the lugs This is the length in the width direction at the side end. ]
(2P−L) / 10 <F <(2P−L) / 2 (2)
[In Formula (2), F is the depth from the lug surface to the center position of the deepest part of the notch recess of the crawler blade, P is the distance between the centers of adjacent lugs, and L is the lug extension side It is the length in the width direction at the end. ]

Images