JP4675488B2 - Elastic crawler - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an elastic crawler used in a crawler type traveling device used as a traveling unit of a construction / civil engineering work machine or an agricultural work machine, and more specifically, a tensile strength embedded in a crawler body. The present invention relates to the structure of the joint portion of the cord band.
[0002]
[Prior art]
Conventionally, as a traveling device, a drive sprocket disposed on one side in the traveling direction, an idler disposed on the other side, a plurality of wheels disposed between the drive sprocket and the idler, a drive sprocket, an idler, and A pair of endless belt-shaped rubber crawlers wound around the wheels, and a pair of left and right running bodies that rotate and drive the rubber crawler in the circumferential direction by rotating the drive sprocket. There is a crawler type traveling device.
[0003]
In the rubber crawler, a core metal in the crawler width direction is embedded in an endless belt-shaped crawler body made of rubber at intervals in the crawler circumferential direction (band longitudinal direction) and over the entire crawler circumferential direction. The main composition.
In addition, since extremely large tension (tension) acts on the rubber crawler in the crawler circumferential direction, the crawler circumferential tensile strength cord surrounding the cored bar is embedded in the crawler body in parallel in the crawler width direction. Tensile bodies (cord belts) are provided.
[0004]
Japanese Patent No. 2863588 is constructed by arranging a plurality of end-tensioned tensile cords wound in the crawler circumferential direction as a plurality of tension members arranged in parallel in the crawler width direction. (Conventional example 1).
In this structure, one tensile strength cord is formed into an annular shape by overlapping (lap jointing) its end side portions in the crawler body.
[0005]
In addition, the ends of the tensile strength cords are arranged and formed so as to be aligned in the crawler width direction.
Note that the tip of the tensile cord refers to the longest portion of the cord, and the end portion refers to a portion that is at a certain distance from the tip of the tensile cord.
In the prior art, the tips of the tensile strength cords are arranged so as to be aligned in the crawler width direction. Clearly, there is a difference in rigidity before and after this portion (front and rear in the crawler circumferential direction). The difference in rigidity is large. Then, when the rubber crawler is wound around the drive sprocket or the like and is bent and tension in the circumferential direction of the crawler acts on the tensile strength cord, a stress that the end side portion of each tensile strength cord tends to return is generated. However, since the ends of the tensile strength cords are aligned in a straight line in the crawler width direction, stress is concentrated on the straight line in the crawler width direction, which causes the tensile strength cord to peel off (the rubber is peeled off from the cord). .
[0006]
Japanese Patent Laid-Open No. 12-103374 discloses that a rubber elastic body having a long end and a steel cord row embedded in the longitudinal direction and projecting from the end portion are projected. At the endless part where the steel cord rows are overlapped, unvulcanized rubber is arranged on the overlapped portion, and then this unvulcanized rubber is vulcanized to make it endless, the tip of the overlap portion of the steel cord rows Has proposed a structure of an endless portion of a rubber crawler characterized in that a plurality of stepped portions or inclined portions are formed in the width direction of the rubber elastic body (2 of the conventional example).
[0007]
Further, Japanese Patent Laid-Open No. 2000-247272 states that “both ends of a steel cord with ends are overlapped in the direction of the inner and outer peripheral surfaces of the rubber crawler at the overlapping portion, and the steel cord is placed in the rubber elastic body. A rubber crawler which is an embedded rubber crawler, characterized in that the steel cord embedded portion on the rubber crawler inner peripheral side of the overlapping portion is arranged on the rubber crawler inner peripheral side with respect to the other embedded portions. (3 of the conventional example).
[0008]
[Problems to be solved by the invention]
In the conventional example 1 described above, stress is concentrated on a straight line in the crawler width direction, and the cause of peeling of the tensile strength cord has not been eliminated.
Further, in the conventional example 2, since the tip of the overlap portion of the steel cord row forms a plurality of steps or inclined portions in the width direction of the rubber elastic body, the steel cord row is rigid when overlapped. In such a configuration, the life of the endless part is improved.
[0009]
However, considering that the position of the end portion is an important factor in relation to a reinforcing core body (also referred to as a cored bar or a horizontal reinforcing body) embedded in the crawler body with a gap in the longitudinal direction of the belt. It was difficult to relax the rigidity smoothly.
Further, in the conventional example 3, the vibration at the time of traveling at a high speed is reduced, and the rigidity at the joint portion (overlap portion) is not reduced.
[0010]
The present invention provides a method for arranging reinforcing cores when end portions of cord strips configured by aligning end tensile strength cords in a line are cut into a bias and overlapped in the direction of the inner and outer peripheral surfaces. The object is to find that there is a correlation with the pitch (buried pitch) and to reduce the rigidity of the joint.
In particular, the end of the cord band on the outer peripheral surface is at the position of the traveling lug, and the center of bending (referred to as a neutral bending surface) at the winding portion (spotted portion) is the presence of the cord band on the inner peripheral surface. Although it is configured to be difficult to cut because it moves smoothly to the end, the end of the cord band on the inner peripheral surface is pressed by the cord band on the outer peripheral surface, etc. An elastic crawler is provided in which the end portion is bias-cut to smoothly relax the rigidity, and the bending center position is gradually shifted to the cord on the inner peripheral surface side.
[0011]
[Means for Solving the Problems]
The elastic crawler according to the present invention includes an endless belt-like crawler body 3 in which a reinforcing core body 2 is embedded with an interval in the longitudinal direction of the belt, and an end tensile strength cord 4 in parallel in the width direction of the crawler body 3. and a code of strips 5 which is formed by, and embedded in the crawler body 3 constituted by superposed inner and outer circumferential direction of the crawler body 3 at combined portion R overlapping the ends of the coding band body 5 endlessly an elastic crawler 1 comprising Te, the edge of the end-defined portion 5A is a distal end portion of the inner circumferential side of the crawler body 3 of the opposite ends of the front superimposed Kiko over de band member 5, with respect to the width direction The portion of the cord band 5 which is formed to extend in the circumferential direction while being inclined and is on the outer peripheral side of the crawler body 3 in the overlapping portion R is between the other portions except the overlapping portion R. The overlap start portion 5C of the overlap Positioned on the outer peripheral side of the other part excluding the part R, on the inner peripheral side of the crawler main body 3 of the overlapping start part 5C, and generated by the overlapping start part 5C. A rigidity adjusting body 12 is embedded in the crawler main body 3 between the inner peripheral portion and the other portion so that the thickness in the inner and outer peripheral directions increases and the rigidity is gradually reduced as the overlap portion R is approached. It is characterized by that.
[0012]
The “both ends” in the “both ends of the superimposed cord strip 5” refer to all the overlapped portions having a certain length including both end edges of the cord strip 5. Further, the “other part” in the “other part excluding the superposition part R” does not include the “superposition start part 5C”, and therefore the cord band 5 is a double superposition. It consists of an aligning portion R, an overlapping start portion 5C, and “another portion”.
[0013]
The rigidity adjusting body 12 is embedded over at least one pitch in the embedding pitch P of the reinforcing core body 2.
Preferably, the end edge of the end portion 5A is formed so as to extend in the circumferential direction while being inclined with respect to the width direction over at least two pitches of the embedded pitch P of the reinforcing core body 2.
[0014]
By adopting such a configuration, when the width of the cord strip 5 and the embedding pitch of the reinforcing core 2 are constant, the cord band 5 is 2.0 as compared with the one cut with a bias angle over 1.5 pitches. In the present invention in which the embedded pitch is used, the bias cutting length is increased, and the rigidity can be gradually relaxed, so that high durability can be achieved.
The distal end 5A-1 in the circumferential direction at the edge of the end portion 5A is disposed so as to be located on the center side in the width direction of the crawler body 3 or on the outer side in the width direction of the crawler body 3.
[0015]
Preferably, a running lug in which both or one of the distal end 5A-1 and the rearmost end 5A-2 in the circumferential direction at the edge of the end portion 5A is raised on the reinforcing core 2 and the crawler body 3 is formed. 6 is disposed at a position overlapping one or both of the six in the circumferential direction.
By adopting such a configuration, one or both of the longest and short end portions 5A-1 and 5A-2 of the cord band 5 are sandwiched between the reinforcing core body 2 and the traveling lug 6, and the end portion Peeling is reliably prevented.
[0016]
In here, the rigidity adjusting member 12, hardness of 80 degrees or more rubber material, it is possible to use urethane rubber, as long as supple in the longitudinal direction than the tensile cord 4, also be used code I can .
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of an elastic crawler according to the present invention will be described with reference to the drawings.
1 to 4, the elastic crawler 1 includes an endless belt-like crawler body 3 in which a reinforcing core body 2 is embedded with an interval in the longitudinal direction of the belt, and an end tensile strength cord 4 of the crawler body 3. A cord strip 5 that is arranged in parallel in the width direction, and the ends of the cord strip 5 are overlapped in the direction of the inner and outer peripheral surfaces of the crawler main body 3 at the overlapping portion R to form an endless shape. Buried inside.
[0018]
The reinforcing core body 2 is made of a metal material or a hard resin material, and has guide protrusions 2A on the left and right of the central portion thereof, and has wings 2B on the left and right sides thereof in an outwardly projecting shape. The longitudinal direction of the reinforcing core body 2 is embedded as the width direction of the crawler main body 3, and each of the left and right wing parts 2 </ b> B is surrounded by a cord band 5.
Tensile cord 4 uses steel cords made of several bundles of steel filaments, a nylon cord composed of several bundles of nylon, tetron cord, other aramid fiber cords, etc. The cord 4 is formed in parallel with the width direction of the crawler main body 3 (aligned) to form a cord band 5, and in order to prevent the variation of the cord 4, topping processing of rubber or the like is performed.
[0019]
The endless belt-like crawler main body 3 is made of rubber or other elastomer material, and a running lug 6 is raised on the outer peripheral surface side with an interval in the belt longitudinal direction. In the embodiment illustrated in FIG. The long and short lugs 6A and 6B of the traveling lug 6 that are in the form of one horizontal character are overlapped on the reinforcing core 2 and arranged in the longitudinal direction of the belt as alternating long and short.
As shown in FIG. 3, the elastic crawler 1 configured as described above is wound around a driving sprocket 7, a driven body (idler) 8, and a rolling wheel 10 arranged in a track frame 9, thereby forming a crawler traveling device. is doing.
[0020]
In addition, an engagement window 11 is opened between the reinforcing cores 2 adjacent in the circumferential direction at the central portion in the width direction of the crawler body 3, and the drive claw of the drive sprocket 7 is engaged with and disengaged from the engagement window 11. Thus, the elastic crawler 1 is configured to circulate in the longitudinal direction of the belt.
However, a drive drum or the like may be used instead of the drive sprocket 7, and in this case, it is not necessary to open the engagement window 11.
[0021]
As shown in FIGS. 1 and 2, the end portion 5A on the inner peripheral surface side of the cord band 5 in the overlapping portion R is crawled over at least two pitches in the embedded pitch P of the reinforcing core 2. It is formed at a bias angle in the width direction.
More specifically, as shown in FIG. 1 and FIG. 2, the overlapping portion or length (overlap length) R is a length 4P over five of the reinforcing cores 2, and is on the inner peripheral surface side. The end portion 5A is located on the inner peripheral side through the step portion 5C in the end portion 5B on the outer peripheral surface side, and the cord end is formed at a bias angle in the length 2P over the five reinforcing cores 2. It is.
[0022]
Here, when the width of the cord strip 5 is L and the pitch P of the reinforcing core 2 is constant, and the bias angle is 1 to 1.5 P, the bias angle is steep and the bias length 5D is 2 . By setting it to 0P or more, the bias angle becomes gradual, and as a result, the bias length 5D becomes longer than when 1 to 1.5P, so that the rigidity in the overlap portion R is gradually relaxed.
[0023]
In addition, although the end 5B on the outer peripheral surface side has a horizontal single-letter shape (straight line), the end 5B may be bias cut.
Thus, the reason why the end portion 5A on the inner peripheral surface side of the cord band 5 is bias-cut is as follows.
That is, the end 5B in the cord band 5 on the outer peripheral surface side is the position of the traveling lug 6, and the center of bending at the winding portions 7 and 8 is smoothly transferred to the inner peripheral surface side, so that peeling is performed. In contrast to the configuration that can prevent breakage and the like, the end portion 5A on the inner peripheral surface side is not only pressed by the stepped portion 5C but also sandwiched by the reinforcing core 2, so that the cord Since a large force is applied to this, the bias is cut in the crawler width direction over at least two pitches to gradually relax the rigidity.
[0024]
Further, in the embodiment of FIG. 1, the longest end portion 5A-1 in the end portion 5A on the inner peripheral surface side of the left and right cord strips 5 is located on the center side in the width direction of the crawler body 3, and the shortest end portion 5A-2 is located on the outer side in the width direction. On the other hand, in the embodiment of FIG. 6, the longest end portion 5A-1 is located on the outer side in the width direction, and the shortest end portion 5A-2 is Located in the center in the width direction.
[0025]
Further, as shown in FIG. 1 and FIG. 6, both the longest end portion 5A-1 and the shortest end portion 5A-2 of the end portion 5A on the inner peripheral surface side of the cord band 5 are the reinforcing core 2. Both the upper and the traveling lugs 6 formed on the crawler main body 3 are positioned.
With this configuration, warpage of the longest and short end portions 5A-1, 5A-2 can be suppressed by the reinforcing core body 2 and the traveling lug 6, cracks of the crawler body 3 can be prevented, In other words, when the cord band 5 is steel or the like, the rusting can be prevented.
[0026]
In addition, the crawler main body 3 between the cores 2 in which either one of the longest / short end portions 5A-1 and 5A-2 is shifted from the reinforcing core 2 or the crawler main body between the travel lugs 6 shifted from the travel lugs 6 is used. 3 is also possible.
Further, as shown in FIG. 1, it is desirable that the overlap portions R of the left and right cord strips 5 have the same phase in the longitudinal direction of the belt, but as shown in FIG. It may be.
[0027]
That is, as shown in FIG. 7, when the traveling lug 6 is configured by a so-called slanted lug in an oblique direction, either one of the left and right traveling lugs 6 is always in contact with the ground during traveling to prevent traveling vibration. In this sense, since the lugs 6 are arranged with a phase shift in the circumferential direction (band longitudinal direction), at this time, it is desirable that the overlap portion R be shifted in the circumferential direction on the left and right.
[0028]
As is clear from FIG. 7, when an inclined lug is raised as the traveling lug 6 from the crawler body 3, it is desirable that the bias cut direction in the cord band 5 is a direction along the longitudinal direction of the lug 6. 7, the overlap length R is 7P, the bias angle (length) is 2.5P, the shortest end 5A-2 is on the outer side in the width direction, and the main body between the core bodies 2 3 and the end 5B of the cord band 5 on the outer peripheral surface side is also a bias cut edge.
[0029]
In the case of a short pitch crawler (a crawler in which the arrangement interval P of the cores 2 is shortened), the bias length (angle) may be 3 to 4P.
Furthermore, although the shape of the bias cut edge 5D is illustrated as a straight line in the crawler width direction, it may be a concave curve, a convex curve, or a waveform.
[0030]
The elastic crawler 1 shown in FIGS. 8 to 10 is an overlap start portion between the end portion 5A on the inner peripheral surface side of the cord band 5 and the cord band 5 on the outer peripheral surface side 5B in the overlapping portion R. 5C (step portion 5C of the outer peripheral surface side cord) shows that the rigidity adjusting body 12 is embedded (inserted) in the crawler main body 3, and the basic configuration other than the insertion of the rigidity adjusting body 12 has been described above. Since they are common with the elastic crawler 1, common portions are indicated by common symbols.
[0031]
The rigidity adjusting body 12 is desirably a material having high hardness as long as it is more flexible in the longitudinal direction of the cord than the tensile cord 4 constituting the cord band 5.
For example, in the case of an elastic material (elastomer material) such as rubber or urethane, the JIS shore hardness A may be 80 degrees or more, and may be a knitted fabric such as a steel cord or an organic fiber cord.
[0032]
Also, the insertion length (embedding length) is 1.0 P or more, as long as it extends between the two core bodies 2 as shown in FIG. 9, and as shown in FIG. The stepped portion 5C has a wedge shape in cross section, and the thicker cross section is on the overlap portion R side, whereby the rigidity is gradually reduced.
In the elastic crawler 1 shown in FIG. 8, the overlap length R of the left and right cord bands (configured by arranging the cords 4) 5 is 3P, and the ends of the end portions 5A and 5B in the inner and outer peripheral surface directions. The edge is overlapped with the reinforcing core body 2 and the traveling lug 6 and is cut into a single horizontal shape, and the rigidity adjusting body 12 has the same width as the width L of the cord band 5 at the step portion 5C and is adjacent in the circumferential direction. It is inserted between the matching cores 2.
[0033]
In the elastic crawler 1 shown in FIG. 9, the overlap length R of the cord band 5 formed by aligning the cords 4 is 4P, and the edges of the end portions 5A and 5B in the inner and outer peripheral surface directions are A rigidity adjusting body 12 having a wedge cross section is inserted between the two core bodies 2 adjacent to each other in the circumferential direction on the reinforcing core body 2 and in the step portion 5C.
The elastic crawler 1 shown in FIG. 10 has a left and right cord belt body in which a traveling lug 6 shown as an inclined lug is formed on the crawler body 3 so as to protrude from the left and right in the circumferential direction, and the tensile cords 4 are aligned. The overlap length R in the direction of the inner and outer peripheral surfaces in 5 extends over the seven reinforcing cores 2 in the circumferential direction, that is, 6P, and the end portions 5A and 5B are both biased edges. The phase is shifted in the circumferential direction, and accordingly, both end edges of the rigidity adjusting body 12 are also bias end edges.
[0034]
8 to 10 can be inserted into the crawler main body 3 in the step portion 5C of the elastic crawler 1 shown in FIG. 1, FIG. 2, FIG. 5 and FIG.
Moreover, in each elastic crawler 1 mentioned above, as shown with the code | symbol 13 in FIG. 4, a fiber band can also be inserted (embedded) over the outer peripheral surface of the left and right cord band bodies 5 over the full length of the circumferential direction.
[0035]
The fiber band 13 may be inserted into the inner peripheral surface of the cord band 5 or may be inserted into the inner / outer peripheral surface of the cord band 5 and sandwich the cord band 5.
Furthermore, the left and right fiber bands 13 may be short fibers biased or knitted or woven.
[0036]
【The invention's effect】
According to the present invention described in detail above, when the endless cord band formed by aligning the tensile cords is inserted (embedded) in the crawler body, it is unavoidable at the overlap portion in the inner and outer peripheral surface direction of the cord band. The cord breakage and peeling due to the excessive rigidity can be suppressed, and the durability can be greatly improved. The vibration can also be suppressed.
[Brief description of the drawings]
1 is a plan view showing a first main part of the elastic crawler.
FIG. 2 is a cross-sectional view of FIG.
FIG. 3 is a side view showing an example of a traveling device using an elastic crawler.
4 is a partially enlarged cross-sectional view of the elastic crawler of FIG. 3;
FIG. 5 is a perspective view showing a main part of an elastic crawler .
FIG. 6 is a plan view of a main part of another elastic crawler .
FIG. 7 is a plan view of a main part of another elastic crawler .
FIG. 8 is a plan view of a main part of another elastic crawler .
FIG. 9 is a cross-sectional view of a main part of another elastic crawler .
FIG. 10 is a plan view of a main part of another elastic crawler .
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Elastic crawler 2 Reinforcement core 3 Crawler main body 4 Tensile cord 5 Cord belt 5A, 5B Ended part
12 Stiffness adjustment body
5C Overlay start part
P Embedding pitch R Overlap part (length)

Claims (5)

An endless belt-like crawler body (3) in which reinforcing cores (2) are embedded with an interval in the longitudinal direction of the belt and an endured tensile cord (4) in parallel in the width direction of the crawler body (3) and a code of strips (5) comprising, configured to the code of strips (5) inside and outside circumferential direction overlapping with endless countercurrent mating portion overlapping both ends crawler body at (R) (3) of An elastic crawler (1) embedded in the crawler body (3),
Edge of end-defined portion is the tip portion of the inner circumferential side of the crawler body (3) of the ends of the superimposed pre-Kiko over de band body (5) (5A) is inclined with respect to the width direction While being formed to extend in the circumferential direction,
The portion of the cord band (5) on the outer peripheral side of the crawler main body (3) in the overlapping portion (R) is the overlapping start portion with the other portions excluding the overlapping portion (R) By (5C), it is located on the outer peripheral side with respect to the other portion excluding the overlapping portion (R),
On the inner peripheral side of the crawler body (3) of the overlapping start portion (5C), the inner peripheral side portion and the other portion of the overlapping portion (R) generated by the overlapping start portion (5C) In between the crawler body (3), a rigidity adjusting body (12) that gradually increases the thickness in the inner and outer peripheral directions and gradually relaxes the rigidity as it approaches the overlapping portion (R). Elastic crawler characterized by. The elastic crawler according to claim 1, wherein the rigidity adjusting body (12) is embedded over at least one pitch in the embedded pitch (P) of the reinforcing core body (2) . The edge of the end portion (5A) is
The elastic crawler according to claim 1, wherein the elastic crawler is formed so as to extend in the circumferential direction while being inclined with respect to the width direction over at least two pitches of the embedding pitch (P) of the reinforcing core body (2). . The most distal end (5A-1) in the circumferential direction at the edge of the end portion (5A) is located at the center in the width direction of the crawler body (3) or the outer side in the width direction of the crawler body (3).
The elastic crawler according to claim 1 . Either or either of the most distal end (5A-1) and the last end (5A-2) in the circumferential direction at the edge of the end portion (5A) is on the reinforcing core (2) and the crawler body (3). 5. The elastic crawler according to claim 3 , wherein the elastic crawler is arranged at a position overlapping with one or both of the traveling lugs (6) formed in a circumferential direction in the circumferential direction .

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