JP2020045044A - Elastic crawler - Google Patents

Abstract

To provide an elastic crawler 4 that improves productivity while suppressing a decrease in durability.SOLUTION: An elastic crawler 4 comprises many plate-like core grids 22 that are arranged at intervals in a circumferential direction, and a cord layer 24 that is extended in the circumferential direction on the outside of the core grid. The cord layer 24 includes a plurality of looped units 40 that are juxtaposed in a width direction. Each of the units 40 is composed of a belt-like body 36 that is spirally wound twice or more, and the belt-like body 36 includes at least one steel cord 34. A starting end 42 and a terminal end 44 of the belt-like body 36 constituting the unit 40 are arranged directly above any one of the core grids 22.SELECTED DRAWING: Figure 4

Description

  The present invention relates to an elastic crawler. More specifically, the present invention relates to an elastic crawler mounted on a traveling device such as an agricultural machine or a construction machine.

  BACKGROUND ART Crawler-type traveling devices such as agricultural machines such as combine harvesters and tractors and construction machines such as backhoes are equipped with endless belt-shaped elastic crawlers.

  In the traveling device, the rotation of the sprocket causes the elastic crawler to move in the circumferential direction. Thereby, the traveling device travels.

  The elastic crawler, as disclosed in Patent Document 1, for example, includes an elastic member made of a crosslinked rubber, a large number of metal cores arranged at intervals in the circumferential direction, and extends circumferentially outside these metal cores. A code layer. In the elastic crawler, the core metal and the cord layer are embedded in an elastic member.

  In elastic crawlers, the cord layer is endless and includes steel cord. As this cord layer, for example, a cord layer is formed by arranging a number of steel cords in parallel in the width direction and joining both ends of the cord bundle (hereinafter, a non-jointless type cord layer). Also, a cord layer (hereinafter, a jointless type cord layer) obtained by spirally winding a belt-like body including a steel cord in a circumferential direction is known.

JP 2015-131536 A

  In the running state, considerable tension acts on the cord layer. In the above-described elastic crawler employing the non-jointless type cord layer, since the joint portion includes many seams of the steel cord, the strength of the joint portion may be insufficient, and sufficient durability may not be obtained.

  On the other hand, the above-mentioned jointless type cord layer has no seam of steel cord, so that this cord layer has sufficient strength throughout. Therefore, an elastic crawler employing a jointless type cord layer is expected to have good durability. However, the formation of this code layer requires a strip having a sufficient length. For this reason, it is necessary to prepare a strip having a length adjusted according to the specifications of the elastic crawler to be manufactured, and there is a possibility that a large number of intermediate products will be generated. In addition, a strip having a short length cannot be used for forming a code layer, and thus must be discarded. An elastic crawler employing a jointless type cord layer tends to have lower productivity than an elastic crawler employing a non-jointless type cord layer.

  The present invention has been made in view of such a situation, and an object of the present invention is to provide an elastic crawler that has improved productivity while suppressing a decrease in durability.

A preferred elastic crawler according to the present invention includes a plurality of plate-shaped cored bars arranged at intervals in the circumferential direction, and a cord layer extending in the circumferential direction outside the cored bar.
In this elastic crawler, the code layer includes a plurality of loop-shaped units arranged in parallel in the width direction, and each unit is formed of a belt-like body wound spirally two or more times, and the belt-like body includes at least one belt-like body. Including steel cord.
In this elastic crawler, the start end and the end of the belt-like body constituting the unit are disposed immediately above any of the cored bars.

  Preferably, in this elastic crawler, the end of one band forming one unit and the other band forming another unit located adjacent to the one unit are provided immediately above one core metal. The start end is arranged so as to face the start end.

  Preferably, in the elastic crawler, the code layer includes a first zone in which the number of cross-sections of the band included in the cross section of the code layer is large, and a second zone in which the number of cross-sections of the band included in the cross section is small. Are configured. The circumferential length of the first zone is shorter than the circumferential length of the second zone.

  Preferably, in this elastic crawler, a start end and an end of the strip are located in the first zone.

  Preferably, in this elastic crawler, the end of one band and the other band are located immediately above the one core metal with respect to the number of cross sections of the band included in the cross section of the cord layer in the second zone. The ratio of the number of portions arranged so as to face the start end is 1% or more and 50% or less.

  Preferably, in this elastic crawler, the end of one band and the beginning of another band are disposed so as to face each other just above the one core with respect to the circumferential length of the core. Is 50% or less.

  In the elastic crawler of the present invention, a band including at least one steel cord is used for forming the cord layer. In particular, this cord layer is configured by combining a plurality of units obtained by spirally winding a belt-shaped body. With this elastic crawler, there is no need to prepare a strip having a sufficient length, unlike the above-described jointless type cord layer. With this elastic crawler, it is possible to reduce the size of the bobbin used for storing the strip. Since a strip which is short in length and cannot be used for forming the cord layer is less likely to be generated, the amount of discarded strip can be reduced. This elastic crawler can contribute to an improvement in productivity.

  Further, in this elastic crawler, each unit constituting the code layer is formed of a belt-like body that is spirally wound two or more times. This unit has a jointless structure. This unit does not include steel cord seams. In this cord layer, the number of seams of the steel cord is smaller than that of the above-mentioned non-jointless type cord layer. The strength of this elastic crawler is sufficiently higher than that of an elastic crawler employing a non-jointless type cord layer. Further, by controlling the number of seams of the steel cord, the elastic crawler can obtain the same strength as that of the elastic crawler employing the above-mentioned jointless type cord layer.

  In this elastic crawler, the start end and the end of the belt-like body constituting the unit are arranged immediately above any of the cored bars. In this elastic crawler, the deformation of the portion where the start or end of the steel cord is located is suppressed, so that the end of the steel cord is effectively prevented from jumping.

  In this elastic crawler, the effect of the cord layer on the durability is effectively suppressed even though the cord layer includes a seam of the steel cord. This elastic crawler can improve productivity while suppressing a decrease in durability.

  ADVANTAGE OF THE INVENTION According to this invention, the elastic crawler which achieved improvement of productivity, suppressing the fall of durability is obtained.

FIG. 1 is a side view showing a part of a traveling device equipped with an elastic crawler according to an embodiment of the present invention. FIG. 2 is a sectional view showing a section of the elastic crawler of FIG. FIG. 3 is a perspective view showing a part of the band for the cord layer. FIG. 4 is a plan view illustrating the configuration of the code layer. FIG. 5 is a sectional view showing a section of the code layer. FIG. 6 is a side view illustrating the configuration of the code layer. FIG. 7 is a plan view illustrating a modified example of the code layer.

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

[Traveling device]
FIG. 1 shows a part of a traveling device 2 of a crawler type. Examples of the traveling device 2 include agricultural machines such as a combine and a tractor, and construction machines such as a backhoe. The traveling device 2 includes an elastic crawler 4, a sprocket 6, an idler 8, and a wheel 10.

  The elastic crawler 4 has an endless belt shape. The elastic crawler 4 has a hole 12 at the center in the width direction. In this elastic crawler 4, a large number of holes 12 are arranged at intervals in the circumferential direction. The sprocket 6 and the idler 8 have a disk shape, and are rotatably supported by the main body of the traveling device 2. The sprocket 6 has a number of teeth 14 on its outer circumference.

  In the traveling device 2, the elastic crawler 4 is wound around the sprocket 6 and the idler 8. Thereby, a predetermined tension is applied to the elastic crawler 4.

  In this traveling device 2, the sprocket 6 is rotated by driving means (not shown). As a result, the teeth 14 of the sprocket 6 sequentially enter the holes 12 of the elastic crawler 4. The elastic crawler 4 is moved in the circumferential direction by the teeth 14 having entered the holes 12 moving in the rotation direction of the sprocket 6. Thus, the traveling device 2 travels. When the elastic crawler 4 moves, the idler 8 rotates.

  In this traveling device 2, a plurality of wheels 10 are arranged on the road surface side. These wheels 10 are located between the sprocket 6 and the idler 8. The wheels 10 are rotatably supported by the main body of the traveling device 2. In the traveling device 2, the rolling wheels 10 roll on the inner peripheral surface of the elastic crawler 4 that moves in the circumferential direction.

[Elastic crawler 4]
FIG. 2 shows a cross section of the elastic crawler 4 along the line II-II in FIG. FIG. 2 shows a cross section of the elastic crawler 4 along a plane perpendicular to the circumferential direction of the elastic crawler 4.

  2, the left-right direction is the width direction of the elastic crawler 4. 2, the vertical direction is the thickness direction of the elastic crawler 4. As shown in FIG. 1, the elastic crawler 4 forms a loop. The upper side in FIG. 2 is inside the loop, and the lower side in FIG. 2 is outside this loop. In FIG. 2, the direction perpendicular to the paper surface is the circumferential direction of the elastic crawler 4. The circumferential direction of the elastic crawler 4 is also the length direction of the elastic crawler 4. The circumferential direction of the elastic crawler 4 is orthogonal to the width direction.

  The elastic crawler 4 includes a lug 16 and a guide 18 as shape elements in addition to the hole 12 described above.

  The lug 16 projects outward from the main body 4 a of the elastic crawler 4. The lug 16 extends substantially in the width direction of the elastic crawler 4. As shown in FIG. 1, in this elastic crawler 4, a large number of lugs 16 are arranged at intervals in the circumferential direction. The lug 16 contributes to the traction of the traveling device 2.

  The guide 18 protrudes inward from the main body 4 a of the elastic crawler 4. As shown in FIG. 1, in the elastic crawler 4, a large number of guides 18 are arranged at intervals in the circumferential direction. As shown in FIG. 2, in the width direction, two guides 18 are arranged at an interval in the center of the elastic crawler 4. The two guides 18 sandwich the sprocket 6 when the elastic crawler 4 is running. Thereby, the displacement of the elastic crawler 4 in the width direction is suppressed. The guide 18 contributes to the traveling stability of the traveling device 2.

  The elastic crawler 4 includes an elastic member 20, a core 22, a cord layer 24, and a canvas layer 26 as constituent elements.

  The elastic member 20 is made of a crosslinked rubber. The elastic member 20 covers the metal core 22, the cord layer 24, and the canvas layer 26. In the elastic crawler 4, the metal core 22, the cord layer 24 and the canvas layer 26 are embedded in the elastic member 20.

  The core metal 22 is plate-shaped. The core metal 22 includes a pair of flanges 28 and a pair of wings 30. The pair of flanges 28 are arranged at the center of the metal core 22 in the width direction. In FIG. 2, each flange 28 projects inward from the base 32 of the cored bar 22. In the elastic crawler 4, the flange 28 of the core metal 22 forms a part of the guide 18 described above. The pair of wings 30 are plate-shaped. The wings 30 each extend outward in the width direction from the base 32. In the elastic crawler 4, the above-described lug 16 is formed outside the metal core 22.

  In this elastic crawler 4, the core metal 22 is made of metal. Examples of the material of the core metal 22 include ordinary steel and alloy steel.

  The elastic crawler 4 includes a large number of metal cores 22. These metal cores 22 are arranged at intervals in the circumferential direction.

  The code layer 24 extends in the circumferential direction. The code layer 24 has an endless band shape. In the width direction, the outer end of the code layer 24 is arranged so as to be located inside the outer end of the cored bar 22.

  This cord layer 24 includes a steel cord 34. In this cord layer 24, the steel cord 34 extends substantially in the circumferential direction. In the present invention, “substantially in the circumferential direction” means that the angle formed by the steel cord 34 with respect to the circumferential direction is 5 ° or less. In the elastic crawler 4, from the viewpoint of securing the rigidity of the cord layer 24, the angle formed by the steel cord 34 with respect to the circumferential direction is preferably 3 ° or less, more preferably 2 ° or less.

  In the elastic crawler 4, a steel cord generally used in the elastic crawler is used as the steel cord 34. Although not shown, in the elastic crawler 4, a cord formed by further twisting a plurality of strands formed by twisting a plurality of filaments is used as the steel cord 34.

  In the elastic crawler 4, the code layer 24 is located outside the metal core 22. As shown in FIG. 2, the elastic crawler 4 includes a pair of cord layers 24. Each of the cord layers 24 extends in the circumferential direction outside each of the wings 30 provided on the left and right of the core metal 22.

  The canvas layer 26 is located inside or outside the cord layer 24 outside the metal core 22 and extends in the circumferential direction. This canvas layer 26 has an endless belt shape.

  This canvas layer 26 is a fabric. Although not shown, the canvas layer 26 includes a canvas cord made of organic fibers. The organic fibers include nylon fibers, polyester fibers, rayon fibers and aramid fibers. In this elastic crawler 4, the canvas cord is inclined with respect to the circumferential direction. The inclination angle of the canvas cord is usually set in the range of 20 ° to 70 °. Preferably, the inclination angle of the canvas cord is 30 °.

  The elastic crawler 4 includes a pair of canvas layers 26. Each of the canvas layers 26 extends along the cord layer 24 outside each of the wings 30 provided on the left and right of the core metal 22. As shown in FIG. 2, the canvas layer 26 of the elastic crawler 4 is formed by wrapping the cord layer 24 with the above-described fabric. This canvas layer 26 covers the code layer 24. In the elastic crawler 4, the canvas layer 26 is located between the cored bar 22 and the code layer 24, that is, inside the code layer 24 and outside the code layer 24. In this elastic crawler 4, the canvas layer 26 may be provided only inside the code layer 24. This canvas layer 26 may be provided only outside the code layer 24.

  As described above, the cord layer 24 extends in the circumferential direction outside the wing portion 30 of the metal core 22. The cord layer 24 includes a steel cord 34 that extends substantially circumferentially. In this elastic crawler 4, the code layer 24 is configured using the belt-like body 36 shown in FIG. The strip 36 includes at least one steel cord 34. In the belt-like body 36, the steel cord 34 is covered with a topping rubber 38. The strip 36 includes a steel cord 34 and a topping rubber 38.

  The band 36 shown in FIG. 3 includes two steel cords 34. In the strip 36, the steel cords 34 are arranged in parallel in the width direction. In this elastic crawler 4, the strip 36 can include a plurality of steel cords 34 arranged in parallel in the width direction.

  In the elastic crawler 4, the number of the steel cords 34 included in the strip 36 is preferably two or more from the viewpoint of contributing to improvement in productivity and obtaining the cord layer 24 having sufficient rigidity. The number of the steel cords 34 included in the band 36 is preferably 5 or less, more preferably 4 or less, and still more preferably 3 or less.

  FIG. 4 shows a part of the code layer 24 together with the core metal 22. 4, the horizontal direction is the width direction of the elastic crawler 4, and the vertical direction is the circumferential direction of the elastic crawler 4. The direction perpendicular to the paper surface is the thickness direction of the elastic crawler 4. The front side of the paper is outside the loop formed by the elastic crawler 4.

  In this specification, the configuration of the code layer 24 will be described based on the left code layer 24a shown in FIG. In the elastic crawler 4, the right code layer 24b has the same configuration as that of the left code layer 24a.

  In this elastic crawler 4, the code layer 24 includes a plurality of loop-shaped units 40 arranged in parallel in the width direction. The code layer 24 shown in FIG. In the elastic crawler 4, the unit 40a located inside in the width direction is the first unit 40a, the unit 40b located outside the first unit 40a in the width direction is the second unit 40b, and the second unit 40b The unit 40c located on the outside in the width direction is the third unit 40c. The code layer 24 includes a first unit 40a, a second unit 40b, and a third unit 40c. In the elastic crawler 4, the first unit 40a is the innermost unit 40 in the width direction among the plurality of units 40 constituting the code layer 24. The third unit 40c is the outermost unit 40 in the width direction among the plurality of units 40 constituting the code layer 24.

  In the elastic crawler 4, the unit 40 forming a part of the code layer 24 is formed by spirally winding the belt-like body 36. In other words, the unit 40 is composed of the strip 36 wound spirally. In FIG. 4, the direction indicated by arrow A is the direction in which the band 36 constituting the code layer 24 circulates. In the elastic crawler 4, the cord layer 24 is formed by winding each band 36 in the direction A of the circumferential direction.

  In the code layer 24 shown in FIG. 4, the first unit 40a, the second unit 40b, and the third unit 40c, that is, all the units 40 constituting the code layer 24 are each spirally wound two or more times. It is composed of a strip 36. In this elastic crawler 4, the band 36a for the first unit 40a is called a first band 36a, the band 36b for the second unit 40b is called a second band 36b, and the third unit 40c Is called a third band 36c.

  In the present invention, the number of turns of the band 36 is obtained by counting the number of times that the band 36 passes the position of the start end 42 of the band 36 in the winding of the band 36. Even if the position of the end 44 of the strip does not coincide with the position of the start end 42 in the circumferential direction, the end 44 is disposed immediately above the core 22 on which the start 42 is disposed. If so, it is determined that the position of the terminal end 44 coincides with the position of the start end 42 in the circumferential direction, and the number of turns of the strip 36 is counted.

  In the elastic crawler 4, the unit 40a located on the inner side in the width direction, that is, the first unit 40a is configured using the first belt-shaped body 36a. In the elastic crawler 4, the starting end 42 a of the first band-shaped body 36 a is disposed immediately above the wing 30 of one of the cores 22 included in the elastic crawler 4. In the elastic crawler 4, the core metal 22a on which the starting end 42a of the first belt-shaped body 36a is disposed is referred to as a first metal core 22a.

  In the code layer 24 shown in FIG. 4, the starting end 42a of the first strip 36a is disposed immediately above the wing 30 of the first metal core 22a. The first band-shaped body 36a is spirally wound three turns, and the terminal end 44a of the first band-shaped body 36a is connected to another core metal 22b (hereinafter, referred to as a second metal bar 22b) located next to the first core metal 22a in the circumferential direction A. It is arranged immediately above the wing portion 30 of the second metal core 22b). Thereby, the first unit 40a is obtained.

  In the elastic crawler 4, the first belt-like body 36 a is wound at least two turns, and the terminal end 44 a of the first belt-like body 36 a is placed immediately above the wing 30 of one of the core metals 22 included in the elastic crawler 4. There is no particular limitation on the position of the terminal end 44a of the first belt-like body 36a as long as it is arranged. For example, the terminal end 44a of the first band-shaped body 36a may be disposed directly above the first metal core 22a on which the start end 42a is disposed. The terminal end 44a of the first band-shaped body 36a may be arranged immediately above another core bar 22c (hereinafter, third core bar 22c) located next to the second core bar 22b. The terminal end 44a of the first band-shaped body 36a may be arranged immediately above another core 22d (hereinafter, fourth core 22d) located next to the third core 22c.

  In the elastic crawler 4, the second unit 40b is configured by using the second band-shaped body 36b after the first unit 40a. In the code layer 24 shown in FIG. 4, the starting end 42b of the second strip 36b is disposed immediately above the wing 30 of the second metal core 22b where the end 44a of the first strip 36a is disposed. The second band-shaped body 36b is spirally wound three turns, and the terminal end 44b of the second band-shaped body 36b is disposed immediately above the wing portion 30 of the third metal core 22c. Thereby, the second unit 40b is obtained.

  In the elastic crawler 4, the second belt 36 b is wound at least two times in the same manner as the first belt 36 a, and the terminal end 44 b of the second belt 36 b is included in any of the elastic crawlers 4. There is no particular limitation on the position of the terminal end 44b of the second band-shaped body 36b as long as it is disposed immediately above the wing portion 30 of the cored bar 22.

  In the elastic crawler 4, the third unit 40c is configured by using the third band-shaped body 36c next to the second unit 40b. In the code layer 24 shown in FIG. 4, the starting end 42c of the third strip 36c is disposed immediately above the wing 30 of the third metal core 22c where the end 44b of the second strip 36b is disposed. The third band-shaped body 36c is spirally wound three turns, and the terminal end 44c of the third band-shaped body 36c is disposed immediately above the wing portion 30 of the fourth metal core 22d. Thereby, the third unit 40c is obtained.

  In the elastic crawler 4, the third band 36c is wound at least two times, like the first band 36a and the second band 36b, and the end 44c of the third band 36c is The position of the terminal end 44c of the third band-shaped body 36c is not particularly limited as long as it is disposed immediately above the wing portion 30 of any of the core metals 22 included in the third metal member 22.

  In this elastic crawler 4, the code layer 24 is obtained by sequentially configuring the units 40 using the plurality of strips 36 in this manner.

  In the elastic crawler 4, a band 36 including at least one steel cord 34 is used for forming the code layer 24. In particular, the code layer 24 is configured by combining a plurality of units 40 obtained by spirally winding the belt 36. With this elastic crawler 4, it is not necessary to prepare a strip having a sufficient length unlike the conventional jointless type cord layer. In this elastic crawler 4, the size of the bobbin used for storing the band-like body 36 can be reduced. In the production of the elastic crawler 4, the strip 36 that is short in length and cannot be used for forming the cord layer 24 is less likely to be generated. This elastic crawler 4 can contribute to an improvement in productivity.

  Further, in the elastic crawler 4, each unit 40 constituting the code layer 24 is composed of a belt-like body 36 spirally wound two or more times. This unit 40 has a jointless structure. This unit 40 does not include a seam of the steel cord 34. For this reason, in the cord layer 24, the number of seams of the steel cord 34 is smaller than in the conventional non-jointless type cord layer. The strength of the elastic crawler 4 is sufficiently larger than that of the elastic crawler employing the non-jointless type cord layer. Further, by controlling the number of seams of the steel cords 34, the elastic crawler 4 can obtain the same strength as the elastic crawler employing the above-described jointless type cord layer.

  In the elastic crawler 4, the start end 42 and the end end 44 of the band 36 constituting the unit 40 are disposed immediately above any one of the cores 22. In the elastic crawler 4, deformation of the portion where the start or end of the steel cord 34 is located is suppressed, so that the end of the steel cord 34 is effectively bounced (hereinafter also referred to as the bounce of the steel cord 34). Is prevented. As described above, in the elastic crawler 4, the lug 16 is formed outside the metal core 22. Therefore, in the elastic crawler 4, the deformation of the portion where the start end or the end of the steel cord 34 is located is effectively suppressed by the lug 44 on the core bar 22, so that the steel cord 34 is more effectively prevented from jumping up. .

  In the elastic crawler 4, the effect of the cord layer 24 on the durability is effectively suppressed although the cord layer 24 includes a seam of the steel cord 34. The elastic crawler 4 can improve productivity while suppressing a decrease in durability.

  In this elastic crawler 4, for example, as shown in FIG. 4, immediately above the second core bar 22b, the end 44a of the first band-shaped body 36a constituting the first unit 40a and the next to the first unit 40a The start end 42b of the second band-shaped body 36b that constitutes the second unit 40b is arranged so as to face the second unit 40b. In the elastic crawler 4, the end 44a of the first strip 36a is disposed immediately above the second core 22b, and the starting end 42b of the second strip 36b is located next to the second core 22b. It may be arranged directly above 22c. The end 44a of the first band 36a is disposed immediately above the second core 22b, and the start end 42b of the second band 36b is disposed immediately above the fourth core 22d further adjacent to the third core 22c. You may.

  In this elastic crawler 4, the end 44 of one strip 36 forming one unit 40 and the starting end 42 of another strip 36 forming another unit 40 located next to the one unit 40. The spacing between them affects the stiffness of the cord layer 24. In this elastic crawler 4, from the viewpoint of securing the rigidity of the code layer 24, the end 44 of one strip 36 constituting one unit 40 and the next to the one unit 40 are provided immediately above the one core bar 22. It is preferable to arrange so as to face the starting end 42 of the other band-shaped body 36 constituting another positioned unit 40.

  As shown in FIG. 4, in this elastic crawler 4, the starting end 42b of the second band-shaped body 36b is spaced from the terminal end 44a of the first band-shaped body 36a in the circumferential direction immediately above the second metal core 22b. Be placed. The start end 42c of the third band-shaped body 36c is disposed immediately above the third core bar 22c and spaced apart from the terminal end 44b of the second band-shaped body 36b in the circumferential direction. In the elastic crawler 4, the starting end 42b of the second band-shaped body 36b and the terminal end 44a of the first band-shaped body 36a may be spliced directly above the second metal core 22b without an interval. The starting end 42c of the third band-shaped body 36c and the terminal end 44b of the second band-shaped body 36b may be spliced directly above the third metal core 22c without any gap.

  In FIG. 4, the double-headed arrow LM indicates the circumferential length of the cored bar 22. The double-headed arrow LD is a space between the end 44 of one strip 36 and the start 42 of the other strip 36, which is disposed right above the metal core 22 so as to face each other, in other words, The circumferential length of the seam of the unit 40.

  In the elastic crawler 4, the circumferential length LD of the joint of the unit 40 affects not only the rigidity of the cord layer 24 but also the jump of the steel cord 34. In the elastic crawler 4, the deformation of the seam is effectively suppressed by the core metal 22 and the spring 40 of the steel cord 34 is more effectively prevented from the viewpoint of the unit 40 relative to the circumferential length LM of the core metal 22. Is preferably 50% or less. When the end 44 of one strip 36 and the start 42 of the other strip 36 are joined together, the length LD in the circumferential direction is 0 mm, so this ratio is 0% or more.

  In the elastic crawler 4, from the viewpoint of preventing the steel cord 34 from jumping up, the core metal 22 is sufficiently overlapped with the band 36, specifically, the steel cord 34 included in the band 36. Specifically, the ratio of the overlap length of the band body 36 and the core metal 22 to the circumferential length LM of the core metal 22 is preferably 25% or more, and more preferably 50% or less.

  FIG. 5 shows a cross section of the code layer 24. FIG. 5A shows a cross section of the code layer 24 along the line aa in FIG. FIG. 5B shows a cross section of the code layer 24 along the line bb in FIG. In FIG. 5, the horizontal direction is the width direction of the elastic crawler 4, and the vertical direction is the thickness direction of the elastic crawler 4. The direction perpendicular to the paper surface is the circumferential direction of the elastic crawler 4.

  In the elastic crawler 4, from the starting end 42a of the first band member 36a constituting the first unit 40a to the terminal end 44c of the third band member 36c constituting the third unit 40c, along the circumferential direction A of the band member 36. In a zone (hereinafter, also referred to as a first zone Z1), as shown in FIG. 5A, the number of the cross-sections of the strip 36 included in the cross-section of the code layer 24 is 10. Since the strip 36 includes two steel cords 34, the number of sections of the steel cords 34 included in the section of the cord layer 24 in the first zone Z1 is 20.

  In the elastic crawler 4, from the end 44c of the third belt 36c constituting the third unit 40c to the starting end 42a of the first belt 36a constituting the first unit 40a, along the circumferential direction A of the belt 36. In a zone (hereinafter, also referred to as a second zone Z2), the number of the cross-sections of the strips 36 included in the cross-section of the code layer 24 is 9, as shown in FIG. Since the belt-like body 36 includes two steel cords 34, the number of sections of the steel cords 34 included in the section of the cord layer 24 in the second zone Z2 is 18.

  In the elastic crawler 4, the number of the cross sections of the strips 36 included in the cross section of the cord layer 24 in the first zone Z1 is larger than the number of cross sections of the strips 36 included in the cross section of the cord layer 24 in the second zone Z2. Many. The code layer 24 of the elastic crawler 4 includes a first zone Z1 in which the number of the cross sections of the strips 36 included in the cross section of the code layer 24 is large, and the number of the cross sections of the strips 36 included in the cross section of the code layer 24. And a second zone Z2 with a small number of radii.

  FIG. 6 shows the cord layer 24 of the elastic crawler 4 mounted on the traveling device 2. In FIG. 6, the position indicated by the reference symbol PS is the position of the terminal end 44c of the third belt-shaped body 36c constituting the third unit 40c. The position indicated by the reference sign PU indicates a position corresponding to the start end 42a of the first belt-shaped body 36a that forms the first unit 40a. The double arrow LZ1 is the circumferential length of the above-described first zone Z1, and the double arrow LZ2 is the circumferential length of the above-described second zone Z2. In the elastic crawler 4, the sum of the circumferential length LZ1 of the first zone Z1 and the circumferential length LZ2 of the second zone Z2 is the circumferential length of the code layer 24.

  As described above, in the second zone Z2, the number of the cross sections of the strip 36 included in the cross section of the cord layer 24 is smaller than that in the first zone Z1. The rigidity of the second zone Z2 is lower than the rigidity of the first zone Z1.

  As shown in FIG. 6, the circumferential length LZ1 of the first zone Z1 is shorter than the circumferential length LZ2 of the second zone Z2. In other words, the ratio of the circumferential length LZ1 of the first zone Z1 to the circumferential length (LZ1 + LZ2) of the code layer 24 is less than 0.5. In the elastic crawler 4, since the code layer 24 is mainly constituted by the second zone Z2, the influence of the second zone Z2 on the rigidity of the code layer 24 is suppressed. The elastic crawler 4 maintains good durability. From this point of view, in the elastic crawler 4, the first zone Z1 in which the number of the cross sections of the strip 36 included in the cross section of the cord layer 24 is large, and the second zone in which the number of cross sections of the strip 36 included in this cross section is small Z2 is formed in the code layer 24, and the circumferential length LZ1 of the first zone Z1 is preferably shorter than the circumferential length LZ2 of the second zone Z2.

  In the elastic crawler 4, the circumferential length LZ1 of the first zone Z1 with respect to the circumferential length (LZ1 + LZ2) of the code layer 24 from the viewpoint that the effect of the second zone Z2 on the rigidity of the code layer 24 is effectively suppressed. Is preferably 0.4 or less. From the viewpoint that the highly rigid first zone Z1 can effectively contribute to the rigidity of the code layer 24, the ratio of the circumferential length LZ1 of the first zone Z1 to the circumferential length (LZ1 + LZ2) of the code layer 24 is 0.1. One or more is preferable, and 0.2 or more is more preferable.

  As described above, in the first zone Z1, the number of the cross-sections of the strip 36 included in the cross-section of the cord layer 24 is larger than that of the second zone Z2, and the first zone Z1 has higher rigidity than the second zone Z2. .

  As shown in FIG. 4, in the elastic crawler 4, the start end 42a and the end 44a of the first band 36a, the start 42b and the end 44b of the second band 36b, and the start 42c and the end 44c of the third band 36c. That is, the start end 42 and the end 44 of all the strips 36 constituting the code layer 24 are located in the first zone Z1 having high rigidity. In the elastic crawler 4, the influence of the start end 42 and the end end 44 of the strip 36 on the rigidity of the cord layer 24 is effectively suppressed. The elastic crawler 4 maintains good durability. From this viewpoint, in the elastic crawler 4, the start end 42 and the end 44 of all the strips 36 constituting the code layer 24 are formed in the first zone Z1 in which the number of the cross sections of the strip 36 included in the cross section of the code layer 24 is large. Is preferably located at

  As shown in FIG. 4, in the elastic crawler 4, the code layer 24 is composed of three strips 36, a first strip 36a, a second strip 36b, and a third strip 36c. In the first zone Z1 of the cord layer 24, there is a seam between the first band 36a and the second band 36b, and a seam between the second band 36b and the third band 36c. In other words, in the first zone Z1, a portion where the end 44 of one strip 36 and the starting end 42 of the other strip 36 are arranged directly above the metal core 22 so as to face each other. There are two places.

  In the elastic crawler 4, the code layer 24 is constituted by three strips 36. Assuming that the code layer 24 is constituted by one strip, the code layer 24 includes Constitutes nine loops. In the elastic crawler 4, the code layer 24 has the same number of loops as the number of cross sections of the strip 36 included in the cross section of the code layer 24 in the second zone Z <b> 2. The ratio of the number of the aforementioned seams to the number of loops, that is, one strip just above one cored bar 22 with respect to the number of cross sections of the strips 36 included in the cross section of the cord layer 24 in the second zone Z2. The ratio of the number of places where the terminal end 44 of the body 36 and the start end 42 of the other band-shaped body 36 face each other affects the productivity and durability of the elastic crawler 4.

  In the elastic crawler 4, from the viewpoint of improving the productivity, one band-shaped member is provided immediately above one core 22 with respect to the number of the cross-sections of the band-shaped members 36 included in the cross-section of the cord layer 24 in the second zone Z 2. The ratio of the number of locations where the terminal end 44 of 36 and the start end 42 of the other band-shaped body 36 face each other is preferably 1% or more, and more preferably 5% or more. From the viewpoint of effectively suppressing the decrease in the durability of the elastic crawler 4, the ratio is preferably equal to or less than 50%, and more preferably equal to or less than 35%.

  FIG. 7 shows a modification of the code layer 24 shown in FIG. FIG. 7 shows a part of a code layer 52 as a modification of the code layer 24 together with the core metal 22. In FIG. 7, the horizontal direction is the width direction of the elastic crawler 4, and the vertical direction is the circumferential direction of the elastic crawler 4. The direction perpendicular to the paper surface is the thickness direction of the elastic crawler 4. The front side of the paper is outside the loop formed by the elastic crawler 4. Hereinafter, a modified example of the code layer 24 will be described based on the left code layer 52a shown in FIG. 7, but in the elastic crawler 4, the right code layer 52b is also changed to the left code layer 52a. It has a configuration equivalent to the configuration described above.

  The code layer 52 includes four loop-shaped units 54 arranged in the width direction. Of these four units 54, the unit 54a located on the innermost side in the width direction is the first unit 54a, and the unit 54b located on the outer side in the width direction of the first unit 54a is the second unit 54b. A unit 54c located outside the two units 54b in the width direction is a third unit 54c, and a unit 54d located outside the third unit 54c in the width direction is a fourth unit 54d. In the code layer 52, the fourth unit 54d is the outermost unit 54 in the width direction among the plurality of units 54 constituting the code layer 52.

  Also in this code layer 52, the unit 54 is configured by winding the belt-shaped body 56 in a spiral shape two or more times.

  In the code layer 52 shown in FIG. 7, the starting end 58a of the first band-shaped body 56a is disposed immediately above the wing portion 30 of the first core metal 22a. The first belt-like body 56a is spirally wound two turns, and the terminal end 60a of the first belt-like body 56a is disposed immediately above the wing 30 of the first metal core 22a. Thereby, the first unit 54a is obtained.

  In the code layer 52, the second unit 54b is configured using the second band-shaped body 56b next to the first unit 54a. In this cord layer 52, the start end 58b of the second strip 56b is disposed immediately above the wing 30 of the first metal core 22a where the end 60a of the first strip 56a is disposed. The second band-shaped body 56b is spirally wound three turns, and the terminal end 60b of the second band-shaped body 56b is disposed immediately above the wing portion 30 of the second core metal 22b. Thereby, the second unit 54b is obtained.

  In the code layer 52, the third unit 54c is configured by using the third band-shaped body 56c next to the second unit 54b. In this cord layer 52, the start end 58c of the third band-shaped body 56c is disposed immediately above the wing portion 30 of the second metal core 22b on which the terminal end 60b of the second band-shaped body 56b is disposed. The third belt-like body 56c is spirally wound two turns, and the terminal end 60c of the third belt-like body 56c is disposed immediately above the wing portion 30 of the second core metal 22b. Thus, a third unit 54c is obtained.

  In the code layer 52, the fourth unit 54d is configured using the fourth belt-like body 56d next to the third unit 54c. In this cord layer 52, the start end 58d of the fourth strip 56d is disposed immediately above the wing 30 of the second metal core 22b on which the end 60c of the third strip 56c is disposed. The fourth belt-like body 56d is spirally wound three turns, and the terminal end 60d of the fourth belt-like body 56d is disposed immediately above the wing portion 30 of the third metal core 22c. Thus, a fourth unit 54d is obtained.

  In this elastic crawler 4, the code layer 52 is obtained by sequentially configuring the units 54 using the plurality of strips 56 in this manner. The code layer 52 is configured by alternately combining units 54 each formed by winding the belt 56 twice and units 54 each formed by winding the band 56 three times.

  In FIG. 7, the zone indicated by reference numeral Z1 is the above-described first zone Z1. As shown in FIG. 7, in the cord layer 52, the seam between the first strip 56a forming the first unit 54a and the second strip 56b forming the second unit 54b is connected to the first zone Z1. , That is, in the above-mentioned second zone Z2.

  In the present invention, in the width direction, which is the reference position of the first zone Z1, the core metal 22 on which the starting end 58 of the innermost strip 56 is arranged, or the end of the outermost strip 56. When the seam of the band-shaped body 56 is located immediately above the core metal 22 on which the core 60 is disposed, this seam is considered as a seam included in the first zone Z1. Therefore, in the code layer 52 shown in FIG. 7, the seam between the first strip 56a forming the first unit 54a and the second strip 56b forming the second unit 54b is located in the first zone Z1. To be treated as a seam. In the code layer 52 shown in FIG. 7, the start end 58 and the end 60 of all the strips 56 constituting the code layer 52 have a large number of cross sections of the strips 56 included in the cross section of the code layer 52. It is located in the first zone Z1.

  Also in the elastic crawler 4 including the cord layer 52, the band layer 56 including at least one steel cord 34 is used for forming the cord layer 52. In particular, the code layer 52 is configured by combining a plurality of units 54 obtained by spirally winding a strip 56. With this elastic crawler 4, it is not necessary to prepare a strip having a sufficient length unlike the conventional jointless type cord layer. In this elastic crawler 4, the size of the bobbin used for storing the belt-like body 56 can be reduced. Since the strips 56 that are short in length and cannot be used for forming the code layer 52 are less likely to be generated, the amount of discarded strips 56 can be reduced. This elastic crawler 4 can contribute to an improvement in productivity.

  Further, in the elastic crawler 4, each unit 54 constituting the code layer 52 is composed of a belt-like body 56 wound spirally two or more times. This unit 54 has a jointless structure. This unit 54 does not include the seam of the steel cord 34. For this reason, in the cord layer 52, the number of seams of the steel cord 34 is smaller than in the conventional non-jointless type cord layer. The strength of the elastic crawler 4 is sufficiently larger than that of the elastic crawler employing the non-jointless type cord layer. Further, by controlling the number of seams of the steel cords 34, the elastic crawler 4 can obtain the same strength as the elastic crawler employing the above-described jointless type cord layer.

  In the elastic crawler 4, the starting end 58 and the ending end 60 of the strip 56 forming the unit 54 are disposed immediately above any one of the metal cores 22. In the elastic crawler 4, the deformation of the portion where the start or end of the steel cord 34 is located is suppressed, so that the steel cord 34 is effectively prevented from jumping up.

  In the elastic crawler 4, the effect of the cord layer 52 on the durability is effectively suppressed even though the cord layer 52 includes a joint of the steel cord 34. The elastic crawler 4 can improve productivity while suppressing a decrease in durability.

  As described above, according to the present invention, it is possible to obtain the elastic crawler 4 that achieves an improvement in productivity while suppressing a decrease in durability. From the viewpoint of effectively restraining the steel cord 34 from jumping, the present invention has a remarkable effect particularly in a large combine having a large sprocket diameter.

  The embodiment disclosed this time is an example in all respects and is not restrictive. The technical scope of the present invention is not limited to the above-described embodiment, and includes all modifications within a scope equivalent to the configuration described in the claims.

  Hereinafter, the present invention will be described in more detail with reference to Examples and the like, but the present invention is not limited to only such Examples.

[Example 1]
An elastic crawler having the basic configuration shown in FIG. 2 was manufactured. In Example 1, the cord layer was formed using two strips having the same length including one steel cord. Each of the strips was spirally wound by 10 turns, and two loop-shaped units arranged in the width direction were formed in this code layer.

  In the first embodiment, the start end and the end of the band forming each unit are arranged in the manner shown in FIG. 4, and the start end of the first band is disposed immediately above the wing of the first metal core. The terminal end of the first band was disposed immediately above the second metal core. The starting end of the second band was disposed directly above the wing of the second core, and the end of the second band was disposed immediately above the third core. Therefore, in the first embodiment, immediately above the second metal core, the end of the first band forming the first unit and the second band forming the second unit located next to the first unit are formed. It was arrange | positioned so that the starting end might face. In this code layer, the number of seams of the strip is one.

  In the code layer of the first embodiment, the number of loops constituted by the band, that is, the number of cross sections of the band included in the cross section of the code layer in the second zone was set to 20. With respect to the number of cross-sections of the strips included in the cross-section of the cord layer in the second zone, the end of one strip and the beginning of the other strip are arranged immediately above one core bar so as to face each other. The ratio of the number of locations, that is, the number of seams of the band (unit) is 5%. This is shown in the column of seam ratio in Table 1 below.

  In the first embodiment, since the number of steel cords included in the strip is one, the number of loops constituted by the steel cords is also twenty.

[Comparative Example 1]
An elastic crawler of Comparative Example 1 was obtained in the same manner as in Example 1, except that the cord layer was constituted by winding one belt-like body including one steel cord into 20 turns. Comparative Example 1 is a conventional elastic crawler, and the cord layer of Comparative Example 1 is a conventional jointless type cord layer. This cord layer is not provided with a seam of the strip. In Comparative Example 1, the joint ratio is 0%.

[Comparative Example 2]
The elastic crawler of Comparative Example 2 was constructed in the same manner as in Example 1 except that a cord bundle was formed by arranging 20 steel cords in parallel in the width direction and a cord layer was formed by joining both ends of the cord bundle. Obtained. Comparative Example 2 is a conventional elastic crawler, and the cord layer of Comparative Example 2 is a conventional non-jointless type cord layer. This cord layer was provided with 20 joints of cords. In Comparative Example 2, the joint ratio is 100%.

[Example 2]
An elastic crawler of Example 2 was obtained in the same manner as in Example 1 except that the cord layer was formed using five strips including one steel cord. In the code layer of Example 2, each band was wound four turns at a time, and the number of seams of the band was set to four. In the second embodiment, the joint ratio is 20%.

[Example 3]
An elastic crawler of Example 3 was obtained in the same manner as in Example 1 except that the cord layer was constituted by using ten strips including one steel cord. In the cord layer of Example 3, each band was wound by two turns, and the number of seams of the band was set to nine. In the third embodiment, the joint ratio is 45%.

[Example 4]
An elastic crawler of Example 4 was obtained in the same manner as in Example 1 except that a cord layer was formed using two strips including two steel cords. In the cord layer of Example 4, each band was wound five times, and the number of seams of the band was set to one. In the fourth embodiment, the joint ratio is 10%. In the fourth embodiment, the number of loops formed by the steel cord is 20, which is the same as that of the first embodiment.

[Breaking force]
The tensile breaking strength of the elastic crawler was evaluated using a tensile tester. The results are shown in Table 1 below as indices. The larger the numerical value is, the larger the breaking force is, which is preferable.

[Bending rigidity]
The bending stiffness of the elastic crawler was evaluated using a compression tester. A portion including the first zone of the cord layer was sampled from the elastic crawler and used as a test sample. A disk simulating a sprocket was prepared. The load required when the test sample was wound around this disk was measured, and the maximum value of the load as an index of bending rigidity was obtained. The results are shown in Table 1 below as indices. The larger the numerical value is, the larger the bending rigidity is, which is preferable.

[Bounce]
The bending tester was used to evaluate the jump of the steel cord in the elastic crawler. A portion including the first zone of the cord layer was sampled from the elastic crawler and used as a test sample. The test sample was repeatedly bent, and the time until the steel cord jumped up was measured. The results are shown in Table 1 below as indices. The larger the numerical value is, the less the steel cord jumps up and the more preferable.

[Productivity]
Each of the length of the strip required for the configuration of the unit and the time required for forming the code layer as an index of the amount of disposal of the strip was represented by an index based on Comparative Example 1, and the total value was calculated. The reciprocal of this total value was represented by an index, and the productivity was evaluated. The results are shown in Table 1 below as indices. The larger the value, the better the productivity and the better. In Comparative Example 1, the index was calculated by replacing the length of the strip necessary for the configuration of the unit with the length of the strip required for the configuration of the code layer. In Comparative Example 2, the index was calculated by replacing the length of the strip necessary for the configuration of the unit with the length of one steel cord included in the cord layer.

[Overall performance]
The sum of the indices obtained in each evaluation was calculated. The results are shown in Table 1 below as indices. The larger the value, the better.

  As shown in Table 1, in the example, the productivity is improved while suppressing the decrease in the durability. From the evaluation results, the superiority of the present invention is clear.

  The technology related to the code layer described above can be applied to various elastic crawlers.

DESCRIPTION OF SYMBOLS 2 ... Traveling device 4 ... Elastic crawler 6 ... Sprocket 8 ... Idler 10 ... Roller wheel 12 ... Hole 16 ... Lug 18 ... Guide 20 ... Elastic member 22 ... Core metal 24,52 ... Cord layer 26 ... Canvas layer 28 ... Flange part 30 ... Wing part 34 ... Steel cord 36,56 ... Strip 40,54 ... · Unit 42 · · · Start end of band 36 · · · End of band 36 54 · Unit 58 · Start end of band 56 60 · End of band 56

Claims (6)

Numerous plate-shaped cored bars arranged at intervals in the circumferential direction,
A cord layer extending circumferentially outside the cored bar,
The code layer includes a plurality of loop-shaped units parallel in the width direction,
Each unit consists of a strip that is spirally wound two or more turns,
The strip comprises at least one steel cord;
An elastic crawler, wherein a starting end and a terminating end of a belt-like body constituting the unit are disposed immediately above one of the cored bars.   Immediately above one cored bar, the end of one band forming one unit and the starting end of another band forming another unit located next to the one unit face each other. The elastic crawler of claim 1, wherein the crawler is disposed. In the code layer, a first zone having a large number of cross-sections of the band-shaped body included in the cross-section of the code layer, and a second zone having a small number of cross-sections of the band-shaped body included in the cross-section are configured.
The elastic crawler according to claim 1, wherein a circumferential length of the first zone is shorter than a circumferential length of the second zone.   The elastic crawler according to claim 3, wherein a start end and an end of the strip are located in the first zone.   With respect to the number of cross-sections of the strips included in the cross-section of the cord layer in the second zone, the end of one strip and the beginning of the other strip are disposed immediately above the one core bar. The elastic crawler according to claim 3, wherein a ratio of the number of the locations is 1% or more and 50% or less.   With respect to the circumferential length of the core, the circumferential length between the end of one band and the beginning of the other band, which are disposed so as to face each other immediately above the one core. The elastic crawler according to any one of claims 2 to 5, wherein the ratio is 50% or less.