JPH08216942A - Core for resilient crawler, manufacture thereof and resilient crawler using the core - Google Patents

Abstract

PURPOSE: To manufacture a light core at a low cost by a method wherein the interior of at least the right and left vane parts of a middle part and right and left vane parts is formed in a hollow part, in a core for a resilient crawler having the middle part and the right and left vane part, to which wheels, such as drive wheels, are related. CONSTITUTION: A resilient crawler 20 is formed in such a manner that a number of cores 1A are embedded at equal intervals in a peripheral direction in a crawler body 2 formed of a resilient material, such as synthetic resin. An engaging hole 16 with which a drive wheel 3 is engaged is formed in a middle part in a lateral direction between the cores 1A and a peripheral tensile body 18 is embedded on both sides of the engaging hole 16 and the outer peripheral side of the core 1A. In this case, the core 1A is formed in a hollow state so as to have a middle part 4, to which a wheel is related, and vane parts 5 on both sides by using a steel or an aluminum alloy. The middle part 4 is formed approximately in an elongated oval shape in cross section. Further, the vane part 5 is molded in such a manner that the central part of a pipe in an oval in cross section is pressed by a pressure and front and rear walls 5C and 5D are formed in the shape of a round.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a core bar of an elastic crawler used in agriculture, civil engineering, etc., a method for manufacturing the core bar, and an elastic crawler using the core bar.

[0002]

2. Description of the Related Art Generally, an elastic crawler is constructed by embedding a cored bar in a crawler body made of an elastic material at circumferential intervals, and embedding a tensile body in the circumferential direction on the outer peripheral side of the cored bar. Is formed with an engagement hole with which the drive wheel is engaged, and a lug is integrally projected on the outer peripheral surface of the crawler body.

The cored bar has a midway portion in which wheels such as driving wheels are involved and left and right wing portions thereof, and the left and right wing portions are gradually thinned in the vertical direction from the midway portion side to the left and right outer end sides. There is also a cored bar which has a pair of left and right protrusions projecting toward the inner circumference of the crawler in the middle portion and which is not provided with the protrusions. Such a cored bar is formed of a casting or a forged product, is a heavy product, and it is desired to reduce its weight.
Japanese Patent No. 243 discloses a technique in which only the inside of the protrusion is hollow.

[0004]

In the above prior art, the weight of the protrusion can be reduced, but the weight of the other portions cannot be reduced, and the shape and material that can be formed by drawing are limited. SUMMARY OF THE INVENTION It is an object of the present invention to provide a core bar for an elastic crawler, in which at least the blade part of the core bar and the blade part are hollow so as to reduce the weight of the core bar.

The present invention is a method for manufacturing a core bar for an elastic crawler, which uses a metal tubular material and presses both ends thereof to form blades so that the core bar can be easily and inexpensively manufactured. The purpose is to provide. An object of the present invention is to provide a lightweight elastic crawler by embedding a cored bar having at least a hollow wing portion in a crawler main body made of an elastic material with a circumferential interval.

[0006]

A first specific means for solving the problem in the present invention is a wheel such as a drive wheel 3 which is embedded in a crawler body 2 made of an elastic material at a circumferential interval. In the mandrel for the elastic crawler having the midway portion 4 and the wing portions 5 on the left and right sides thereof, at least the left and right wing portions 5 of the midway portion 4 and the left and right wing portions 5 are formed to be hollow inside.

The second concrete means for solving the problems in the present invention is that, in addition to the first concrete means, the left and right wing portions 5 have upper and lower walls 5A and 5B and front and rear walls 5C and 5D. Then
The upper wall 5A is inclined so as to gradually approach the lower wall 5B from the midway portion 4 to the outer end of the wing portion 5, and the front and rear walls 5C, 5C,
D is substantially parallel, and its upper edge gradually projects upward from the upper wall 5A.

In addition to the first concrete means, the third concrete means for solving the problems in the present invention has the left and right wing portions 5 having upper and lower walls 5A and 5B and front and rear walls 5C and 5D. Then
The upper wall 5A is inclined so as to gradually approach the lower wall 5B from the midway portion 4 to the outer end of the wing portion 5, and the upper and lower walls 5A and 5B are inclined.
That is, the front and rear widths of A and 5B are gradually widened.

The fourth concrete means for solving the problems in the present invention is, in addition to any one of the first to third concrete means, the left and right wing portions 5 have holes 6 at their outer ends which communicate with the inside. Is formed. A fifth specific means for solving the problem in the present invention is that, in addition to the second or third specific means, the lower walls 5B of the left and right wing portions 5 are formed substantially flat. .

The sixth concrete means for solving the problems in the present invention is the concrete means according to any one of the first to third aspects, wherein the midway portion 4 is hollow inside and has a substantially elliptical cross section or a lower surface. Is formed into a flat semi-circular cross section.
The seventh concrete means for solving the problems in the present invention is the sixth concrete means, and in addition to the sixth concrete means, a metal or non-metal core material 7 is inserted in the middle portion 4. That is.

An eighth concrete means for solving the problems in the present invention is, in addition to the first, sixth or seventh concrete means,
A pair of left and right protrusions 9 protruding upward is formed at the left and right ends of the midway portion 4, and the protrusions 9 are formed to be hollow inside. In addition to the first specific means, a ninth specific means for solving the problem in the present invention is such that the midway portion 4 and the left and right wing portions 5 are formed as separate members and welded to each other. That is.

[0012] The tenth for solving the problems in the present invention
The specific means is that, in addition to the ninth specific means, the midway portion 4 is hollow inside and ribs 8 are formed to divide the inside into a plurality of front and rear portions. The eleventh concrete means for solving the problems in the present invention is, in addition to the ninth concrete means, a pair of left and right projecting portions 9 projecting upward are integrally formed at the left and right end portions of the intermediate portion 4. That is what is being done.

The first method for solving the problems in the method of the present invention
The concrete means is to cut a metal tubular material to a required size to form the tubular material 12, leave the middle part 4 of the tubular material 12 for the required size, and reduce both left and right side parts toward the outer end side. That is, the blade portion 5 is formed by press working so that The second concrete means for solving the problem in the method of the present invention is, in addition to the first concrete means, inserting the core material 7 into the midway portion 4 before pressing the left and right side portions. That is.

Third method for solving the problems in the method of the present invention
In addition to the first specific means, the specific means for forming the protruding material 13 is formed by folding a thin metal plate in two, and the protruding material 13 is welded to the left and right ends of the midway portion 4 to form the protruding portion 9. Is being formed. A fourth specific means for solving the problem in the method of the present invention is to form the intermediate member 14 with a metal material, and press the metal tubular material so that it becomes thinner from one end to the other end, and the blade member 15 is formed. That is, the thick side ends of the pair of left and right blade members 15 are welded to both ends of the intermediate member 14.

Fifth for solving the problems in the method of the present invention
In addition to the fourth specific means, the metal intermediate member 14 is a pipe material, a drawn material having ribs inside, a bent material obtained by bending a flat plate, a forged product or a cast product. It is formed by either. The concrete means for solving the problem in the utilization object of the present invention is that the core metal 1 is embedded in a crawler main body 2 made of an elastic material at a circumferential interval, and the core metal 1 is provided in the crawler main body 2 on the outer peripheral side. A pair of left and right tensile members 18 in the circumferential direction are embedded, and engaging holes 16 for engaging the drive wheel 3 are formed between the left and right tensile members 18 and between the core metal 1, and the outer peripheral surface of the crawler body 2 is formed. Engagement hole 16
That is, the lug 17 is integrally molded therebetween.

[0016]

In the core metal 1 embedded in the crawler main body 2 made of an elastic material at a circumferential interval, at least the left and right wing portions 5 of the midway portion 4 and the left and right wing portions 5 are formed to be hollow inside. The weight is reduced by the volume, and the weight is further reduced if the midway portion 4 is also formed to be hollow.

The cored bar 1 is formed into an inner hollow by simply cutting a metal cylinder into a required size and pressing both side parts of the metal cylinder so as to become thinner toward the outer end side. When the core metal 1 is embedded in the crawler main body 2 made of an elastic material at a circumferential interval to form the elastic crawler 20, a hollow portion remains in the elastic crawler 20 to reduce the overall weight and reduce the weight of the blade portion 5. If the upper edges of the front and rear walls 5C and 5D project higher than the upper wall 5A, or if the holes 6 communicating with the inside are formed at the outer ends of the left and right wing portions 5, the elastic material forming the crawler body 2 will infiltrate. The coupling strength between the core metal 1 and the crawler body 2 is increased.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. In the first embodiment shown in FIGS. 1 to 5, the elastic crawler 20 is a crawler main body 2 made of an elastic material such as rubber or synthetic resin. Engagement holes 16 for engaging the drive wheels 3 are formed in the middle of the metal 1A in the left-right direction, and a pair of left and right circumferential tensile members 18 are provided on both the left and right sides of the engagement hole 16 and on the outer peripheral side of the core metal 1A. And a lug 17 is integrally formed between the engagement holes 16 on the outer peripheral surface of the crawler body 2.

The core metal 1A is made of a light metal such as steel, iron or aluminum alloy, and has a wheel 4 including a portion facing the engagement hole 16 with which the drive wheel 3 engages.
And left and right wings 5 thereof, and the middle part 4 has left and right protrusions 9 protruding from both ends thereof to the inner circumference side of the crawler. The left and right wings 5 are left and right outside from the middle part 4 side. The upper and lower wall thickness gradually decreases toward the end. Both ends of the midway portion 4 are also thin so as to be continuous with the wing portion 5.

The midway portion 4 and the left and right wing portions 5 are formed to be hollow inside. As shown in FIG. 3, the midway portion 4 has upper and lower walls 4A and 4B and front and rear walls 4C and 4D. It has a substantially elliptical shape with a horizontally long arc. The lateral shape of the left and right wings 5 is
As shown in FIG. 4, as the lower wall 5B is flat, the upper wall 5A gradually comes closer to the lower wall 5B and comes into contact with the outer ends of the front and rear walls 5C and 5D as the lower wall 5B goes from the midway portion 4 to the outer end of the wing portion 5. Are substantially parallel to each other and their upper edges are projected so as to be higher than the upper wall 5A.

That is, the left and right wing portions 5 are formed by pressing the front and rear center of the upper wall 5A with a press while controlling the front and rear width of the elliptical pipe in section to flatten the lower wall 5B and round the front and rear walls 5C and 5D. The wing portion 5 has a substantially uniform front-rear width, and a hole 6 communicating with the hollow portion in the core metal 1A is left in the center of the front-rear rounded portion. The hole 6 of the wing 5
When the core metal 1A is embedded in the crawler main body 2, the material of the crawler main body 2 can invade to increase the bonding strength between the core metal 1A and the crawler main body 2.

The projection 9 is formed by punching out a thin metal plate such as a steel plate material or an iron plate material, bending it by using a die and press, and
It is formed into a square shape by a process such as folding, and is formed separately from the other parts of the core metal 1A, and is welded to both left and right ends of the midway part 4, and the inside thereof is hollow and the groove 10 is formed. It communicates with the outside through. The material of the crawler body 2 can also penetrate from the groove 10.

In the method of manufacturing the core metal 1A, as shown in FIG. 5, a metal tubular material having a substantially elliptical or circular cross section is cut into a required size to form a tubular material 12 (first step). The tube material 12 is divided into three parts of required length, and the middle part is divided into the middle part 4,
The left and right side portions of the tubular material 12 are pressed so as to become thinner toward the outer end side while leaving the intermediate portion 4 by a required size to form a wing portion 5 (second step), and the plate material is folded in two. To form the protrusion material 13 in a square shape (separate process),
The protrusion material 13 of the protrusion 9 is welded to both ends of the intermediate portion 4 to form the protrusion 9 (third step).

In the second embodiment shown in FIGS. 6 to 8, the cored bar 1B is hollow in all parts, and the cored bar 1A is
And the middle part 4 and the protruding part 9 are the same, and only the shape of the wing part 5 is different. By changing the molding die for the wing part 5,
It can be produced in the same manner as in A. The left and right wings 5 are the lower wall 5B.
Is flat, the upper wall 5A is inclined so as to gradually approach the lower wall 5B as it goes from the midway portion 4 to the outer end of the wing portion 5, and the front and rear walls 5A and 5B are formed so that their front and rear widths are gradually widened. 5C and 5D are gradually lowered, and the upper edge protruding higher than the upper wall 5A is not formed.

This core metal 1B is merely squeezed by a press so that both ends of the cylindrical material 12 come into contact with each other, and holes 6 are formed in the ends by post-processing. Third shown in FIGS.
The core metal 1C of the embodiment is the same as the core metal 1A, and a metal or non-metal auxiliary core material 7 is inserted into the midway portion 4. The core material 7 is preferably made of a lightweight material such as synthetic resin, which reinforces the midway portion 4 and maintains the shape during molding without causing an increase in weight.

In the core metal 1C of the third embodiment, as shown by the chain double-dashed line in FIG. 5, a supplementary core material 7 is separately formed, and after the first step, the auxiliary material is added in the central section of the tubular material 12. It can be manufactured by inserting the core material 7 and performing the second step and the third step in that state. Although the lower wall 5B of the wing portion 5 is formed flat in each of the above-described embodiments, the lower wall 4B of the midway portion 4 can also be formed substantially flat. In that case, the core material 7 is inserted. And molding becomes easy. Then, as shown in FIG. 11, the upper wall 4A
It is also possible to make the shape of an arc so that the cross-sectional shape of the midway portion 4 is substantially semicircular. The curvature of the arc upper wall 4A is set to the drive wheel 3
If it is adapted to the shape of the root of the tooth, the driving force can be transmitted smoothly.

12 and 13 show a fourth embodiment,
In this core metal 1D, a midway portion 4, left and right wings 5, and left and right protrusions 9 are separately formed and welded and fixed. This core metal 1
In the production of D, the intermediate portion 4 is formed by pressing the tubular material into the rectangular tubular intermediate member 14, and the wing portion 5 is formed from the one end to the other end by the tubular material or the press as in the first or second embodiment. The blade member 15 is formed by press working so as to be thin, and the projection 9 is formed by welding the plate material in a cross shape in plan view to form the cross plate 16, and the blade member 15 is welded to both ends of the square tube of the intermediate member 15. The cross plate 16 is welded to both ends of the intermediate member 15.

In place of the tubular member, the intermediate member 14 forming the intermediate portion 4 of this fourth embodiment is provided with ribs 8 which divide the inside into front and rear cavities as shown in FIGS. The drawn material formed can be used, or as shown in FIGS. 16 and 17, the strip can be bent into a square shape, and a bent material with opposite edges or rounded edges can be used. FIG. 18 shows a fifth embodiment. In this core metal 1E, the middle part 4 and the left and right protrusions 9 are integrally formed by forging or casting, and the left and right wing parts 5 are the core metal of the fourth embodiment. It is formed by pressing a tubular material or the like as in 1D. The spigots are formed by the protrusions 22 on both the left and right ends of the midway portion 4, and the positioning is performed when the members forming the blade portion 5 are welded.

In the core metal 1E of the fifth embodiment, the inside of the midway portion 4 and the projection portion 9 is formed solid, but as shown by the two-dot chain line, it is opened at the connecting portion with the blade portion 5. It is also possible to form the inside hollow. Similarly to the core metal 1A, the core metal bars 1B to 1E of the second to fifth embodiments are also embedded in the crawler main body 2 made of an elastic material at circumferential intervals so that the elastic crawler 2 can be formed.
0 can be configured.

The protrusion 9 of each of the above-described embodiments is shown as a member for preventing derailment, but in the case of a crawler device provided with a straddle roller, the top surface of the protrusion 9 of the core metal 1 is flattened. It is used by forming it on the surface of a rolling wheel. Further, when the elastic crawler 20 is formed by integrally forming small protrusions projecting forward and backward on the protruding portion 9, the small protrusions of the adjacent cored bar 1 are arranged so as to overlap each other in the circumferential direction. The protrusion may be used to prevent the core metal 1 from swinging in the left-right direction. Further, in the case of a crawler device that does not require the protruding portion 9, the core metal 1 is composed of only the midway portion 4 and the blade portion 5.

[0031]

According to the present invention described in detail above, since at least the left and right wing portions 5 of the middle portion 4 and the left and right wing portions 5 of the core metal 1 are formed to be hollow inside, the weight of the hollow volume is reduced. Can be reduced, and the weight and cost can be reduced. The left and right wing portions 5 have upper and lower walls 5A and 5B and front and rear walls 5C and 5D, and the upper wall 5A is inclined so as to gradually approach the lower wall 5B as going from the midway portion 4 to the outer end of the wing portion 5, The front and rear walls 5C and 5D are substantially parallel to each other, and the upper edges of the front and rear walls 5C and 5D are gradually projected upward from the upper wall 5A, so that the front and rear width of the blade portion 5 can be made substantially uniform over the entire length, and the rigidity of the blade portion 5 can be increased, and When embedded in the crawler body 2, the front and rear walls 5C, 5D
Can be caught with the crawler body 2, and the connection can be more reliably performed.

The left and right wing portions 5 have upper and lower walls 5A and 5B and front and rear walls 5C and 5D. The upper wall 5A gradually approaches the lower wall 5B as it goes from the midway portion 4 to the outer end of the wing portion 5. Since the front and rear walls of the upper and lower walls 5A and 5B are inclined, the front and rear walls are gradually widened, so that the wall thickness of the outer end of the blade portion 5 can be reduced and the crawler on the blade portion 5 when embedded in the crawler body 2 can be reduced. The thickness of the main body 2 can also be reduced.

Since the left and right wing portions 5 are formed with holes 6 communicating with the inside at the outer ends thereof, when embedded in the crawler body 2, the elastic material of the crawler body 2 can invade, so that the core metal 1 and the crawler body 2 can enter. The bond strength of 2 can be improved. Since the lower walls 5B of the left and right wings 5 are formed substantially flat,
When the tensile body 18 is embedded in the crawler body 2 and arranged on the outer peripheral side thereof, the stress applied from the core metal 1 to the tensile body 18 can be reduced, and the durability of the tensile body 18 can be improved.

Since the midway portion 4 is hollow inside and has a substantially elliptical cross section or a semi-circular cross section with a flat lower surface, when it is engaged with the drive wheel 3, the valley of the teeth of the drive wheel 3 is formed. It can be engaged smoothly. Since the metal or non-metal core material 7 is inserted in the middle part 4, the strength of the middle part 4 can be improved, and the shape can be maintained when the wing part 5 is molded.

A pair of left and right projecting portions 9 projecting upward are formed at the left and right end portions of the midway portion 4, and the projecting portions 9 are formed.
Since the core is formed hollow, the weight of the cored bar 1 can be further reduced. Since the midway portion 4 and the left and right wing portions 5 are formed as separate members and welded to each other, the midway portion 4 can be formed in various shapes as well as the tubular shape.

Since the midway portion 4 is hollow inside and ribs 8 are formed to divide the inside into a plurality of front and rear portions, the midway portion 4 can be formed to be lightweight and high in strength. Since a pair of left and right protrusions 9 projecting upward are integrally formed at the left and right ends of the midway portion 4, the protrusions 9 can be easily formed. A metal tubular material is cut to a required size to form a tubular material 12, and the middle part 4 of the tubular material 12 is left with a required size, and the left and right both sides are pressed so that the thickness becomes thinner toward the outer end side. Since the wing portion 5 is formed by the above, the cored bar 1 can be easily and lightweight formed from a tubular material.

Since the core material 7 is inserted into the middle part 4 before the left and right sides are pressed, the core material 7 can be easily inserted and molded using the core material 7. Since the thin metal plate is folded in two to form the protruding material 13, and the protruding material 13 is welded to the left and right ends of the midway portion 4 to form the protruding portion 9, the protruding portion 9 can be formed easily and lightly. .

The intermediate member 14 is formed of a metal material, and the metal tubular material is pressed so as to become thinner from one end to the other end to form the blade member 15, and the pair of left and right blades are formed at both ends of the intermediate member 14. Since the thick side end of the member 15 is welded, the core metal 1 having the intermediate portions 4 of various shapes can be easily manufactured. Since the intermediate member 14 made of a metal material is formed of any one of a pipe material, a drawn material having ribs inside, a bent material obtained by bending a flat plate, a forged product, or a cast product, the intermediate part 4 is made of various materials. And can be formed into a shape, and can easily be manufactured with required strength.

The elastic crawler is the core metal 1 of any of the above.
Are embedded in the crawler body 2 made of an elastic material with a circumferential interval, and a pair of left and right circumferential tensile members 18 are embedded in the crawler body 2 on the outer peripheral side of the core metal 1.
Since the engaging holes 16 for engaging the drive wheels 3 are formed between 8 and the core 1, and the lugs 17 are integrally formed between the engaging holes 16 on the outer peripheral surface of the crawler main body 2, lightweight and inexpensive. Can be manufactured.

[Brief description of drawings]

FIG. 1 is a sectional front view of an elastic crawler having a cored bar embedded therein according to a first embodiment of the present invention.

FIG. 2 is a plan view of the same.

FIG. 3 is a sectional side view of the cored bar according to the first embodiment.

FIG. 4 is a side view of the cored bar according to the first embodiment.

FIG. 5 is an explanatory diagram showing a method of manufacturing a cored bar according to the first embodiment.

FIG. 6 is a front view showing a core metal according to a second embodiment.

FIG. 7 is a plan view of the same.

FIG. 8 is a side view of the same.

FIG. 9 is a sectional front view showing a core metal according to a third embodiment.

FIG. 10 is a sectional side view of the same.

FIG. 11 is a sectional side view showing a modification of the cored bar of the third embodiment.

FIG. 12 is a front view showing a cored bar according to a fourth embodiment.

FIG. 13 is a plan view of the same.

FIG. 14 is a sectional view showing a first modification of the intermediate member of the cored bar of the fourth embodiment.

FIG. 15 is a sectional view showing a second modification of the intermediate member of the cored bar according to the fourth embodiment.

FIG. 16 is a sectional view showing a third modification of the intermediate member of the cored bar of the fourth embodiment.

FIG. 17 is a sectional view showing a fourth modification of the intermediate member of the cored bar of the fourth embodiment.

FIG. 18 is a sectional front view showing a core metal according to a fifth embodiment.

[Explanation of symbols]

 1 core metal 2 crawler main body 3 drive wheel 4 midway portion 5 wing portion 6 hole 7 auxiliary core material 8 rib 9 protrusion

Claims (17)

[Claims] 1. A midway portion (4) embedded in a crawler body (2) made of an elastic material at a circumferential interval and involving wheels such as a drive wheel (3) and left and right wing portions (5) thereof. A cored bar for an elastic crawler, wherein the middle part (4) and the left and right wings (5) are formed so that at least the left and right wings (5) are internally hollow. 2. The left and right wing parts (5) have upper and lower walls (5A, 5A).
B) and front and rear walls (5C, 5D), the upper wall (5A) is inclined so as to gradually approach the lower wall (5B) from the midway part (4) to the outer end of the wing part (5). , Front and rear walls (5
C and 5D) are substantially parallel to each other, and the upper edge of the
2. A protrusion upward from A).
The core bar for the elastic crawler according to. 3. The left and right wings (5) are provided on upper and lower walls (5A, 5A, 5A).
B) and front and rear walls (5C, 5D), the upper wall (5A) is inclined so as to gradually approach the lower wall (5B) from the midway part (4) to the outer end of the wing part (5). The core bar for an elastic crawler according to claim 1, wherein the front and rear walls (5A, 5B) are formed such that the front-rear width thereof is gradually widened. 4. The mandrel for an elastic crawler according to claim 1, wherein the left and right wing parts (5) are formed with holes (6) communicating with the inside at the outer ends. . 5. The lower wall (5B) of the left and right wing parts (5) is formed to be substantially flat.
The core bar for the elastic crawler according to. 6. The halfway portion (4) is hollow inside and is formed to have a substantially elliptical cross section or a substantially semicircular cross section with a flat lower surface. Core bar for elastic crawlers. 7. The mandrel for an elastic crawler according to claim 6, wherein a metallic or non-metallic supplementary core material (7) is inserted in the middle part (4). 8. A pair of left and right protrusions (9) projecting upward are formed at the left and right ends of the midway portion (4), and the protrusions (9) are formed to be hollow inside. The core metal for an elastic crawler according to claim 1, 6 or 7. 9. The core metal for an elastic crawler according to claim 1, wherein the midway portion (4) and the left and right wing portions (5) are formed as separate members and welded to each other. 10. The core bar for an elastic crawler according to claim 9, wherein the midway portion (4) is hollow inside and has ribs (8) dividing the inside into a plurality of front and rear portions. 11. The core for an elastic crawler according to claim 9, wherein a pair of left and right protrusions (9) projecting upward are integrally formed at left and right ends of the midway portion (4). Money. 12. A metal tubular material is cut into a required size to form a tubular material (12), and the left and right both side portions are outer ends while leaving the midway portion (4) of the tubular material (12) by the required size. A method for manufacturing a core bar for an elastic crawler, characterized in that the blade portion (5) is formed by press working so as to become thinner toward the side. 13. The manufacturing of a core bar for an elastic crawler according to claim 12, wherein a supplementary core material (7) is inserted into the middle part (4) before pressing the left and right side parts. Method. 14. A thin metal plate is folded in two to form a protruding material (13), and the protruding material (13) is welded to both left and right ends of the midway portion (4) to form a protruding portion (9). The method for manufacturing a core bar for an elastic crawler according to claim 12, wherein 15. A midway member (14) is formed by forming a midway member (14) from a metal material, and a metal tubular material is pressed so as to become thinner from one end to the other end to form a blade member (15). ), The thick side ends of the pair of left and right blade members (15) are welded to both ends of the above (3). 16. The intermediate member (14) made of a metal material,
The core for an elastic crawler according to claim 15, which is formed of a pipe material, a drawn material having ribs (8) therein, a bent material obtained by bending a flat plate, a forged product, or a cast product. Gold manufacturing method. 17. The cored bar (1) according to any one of claims 1 to 11 is embedded in a crawler main body (2) made of an elastic material at circumferential intervals, and the outer periphery of the cored bar (1). In the crawler body (2) on the side, a pair of left and right circumferential tension members (1
8) is embedded and an engaging hole (16) for engaging the drive wheel (3) is formed between the left and right tensile members (18) and between the core metal (1), and the outer periphery of the crawler body (2) is formed. Surface engagement holes (16)
An elastic crawler characterized in that a lug (17) is integrally molded therebetween.