JP5567814B2 - Rubber track sprocket - Google Patents

Description

  The present invention relates to a rubber crawler sprocket, and more particularly to a rubber crawler sprocket that engages with a driving projection formed on an inner peripheral surface of a crawler main body to drive a rubber crawler.

  In recent years, a driving protrusion is formed on the inner peripheral surface of the crawler body, and a tooth of a sprocket attached to the rotational driving shaft of the traveling machine body is engaged with the driving protrusion, and a driving force is applied to apply rubber. A type of driving the crawler around is widely used.

  FIG. 5 is a schematic side cross-sectional view of an engagement portion between a crawler main body and a sprocket tooth portion regarding a rubber crawler disclosed in Patent Document 1. However, the state where the tooth portion 32 of the sprocket 30 is engaged with the driving projection 24 and the driving force is applied is shown. In FIG. 5, the direction in which the sprocket 30 rotates is indicated by an arrow A. 6 is a cross-sectional view (vertical cross-sectional view) taken along the line B-B ′ of FIG. 5 with respect to the sprocket. FIG. 7 is a developed plan view of the inner peripheral surface side of the crawler body.

  A plurality of metal cores 22 are embedded in the crawler main body 34 at predetermined intervals in the circumferential direction of the crawler main body 34 in a posture in which the wing portions 22 a extend in the width direction of the crawler main body 34. In the width direction of the crawler main body 34, a pair of drive protrusions 24, 24 described later are formed. A recess 20 is formed between the cored bar 22 and the cored bar 22 on the inner peripheral surface side of the crawler main body 34. A lug portion 28 is formed on the ground contact surface E side of the crawler body 34.

  The concave portion 20 is formed while the cored bar 22 on the inner peripheral surface side of the crawler main body 34 is embedded, and is formed in a substantially rectangular shape in plan view in the center portion in the width direction of the crawler main body 34. The depth of the recess 20 has such a depth that it is almost completely filled when the tooth portion 32 is engaged with the drive protrusion 24. The crawler body circumferential side wall forming the recess 20 is curved and formed so as to match the outer shape of the tooth portion 32. The concave portion 20 can be regarded as a part constituting the driving protrusion 24, and when the tooth portion 32 of the sprocket 30 is engaged with the driving protrusion 24, the rotational driving force is efficiently applied to the driving protrusion 24. Is formed to do.

  A pair of protrusions 22c and 22c projecting toward the inner peripheral surface of the crawler main body 34 are formed in the central portion of the core metal 22 in the width direction of the crawler main body 34. These are the same rubber members as the crawler main body 34. Covered to form the pair of drive protrusions 24, 24 described above. The drive protrusion 24 has a function of driving the rubber crawler 34 around by receiving a driving force from the tooth portion 32 of the sprocket 30 and a function of guiding a wheel (not shown).

  The sprocket 30 has a circular base portion 31 and a tooth portion 32, and the tooth portion 32 protrudes in the radial direction from the peripheral portion of the circular base portion 31 of the sprocket 30 and has a predetermined shape in the thickness direction of the circular base portion 31. The protrusion is formed. Accordingly, the tooth portion 32 has a predetermined shape as shown in FIG. The tooth portions 32 are provided at regular intervals on the periphery. The width in the thickness direction of the circular base portion 31 of the tooth portion 32 of the sprocket 30 has a length straddling the two drive protrusions 24 and 24 formed at the substantially central portion of the crawler body 34 in the width direction. The length of the recess 20 formed on the inner peripheral surface side of the crawler body 34 is substantially the same as the length in the crawler body width direction. In FIG. 7, a region where the tooth portion 32 contacts the concave portion 20 is indicated by hatching. This is substantially the same as the area of the recess 20 in plan view.

  In addition, between the pair of left and right drive protrusions 24, 24, in the width direction of the crawler body, a raised portion 26 is formed by building up a rubber member in the upper region of the side wall forming the recess 20. Thereby, when the crawler main body 34 is wound around the sprocket 30, the contact area between the tooth portion 32 and the crawler main body 34 can be increased, and the surface pressure applied by the tooth portion 32 can be reduced.

  Patent Document 2 discloses a configuration different from Patent Document 1 regarding the tooth portion 32 of the sprocket 30. That is, the sprocket is composed of two ring bodies, and a pin is formed between them. This pin corresponds to the tooth portion 32 of Patent Document 1, and this pin is configured to apply a driving force to a rubber protrusion which is a driving protrusion. However, the pin does not straddle the two rings, but has a configuration in which the central portion is cut away.

  Patent Document 3 discloses a plurality of types of sprockets in which pins are formed between two ring bodies (circular plates), as in Patent Document 2, in which pins are arranged in a so-called staggered pattern. There is something that has been. That is, the distance between the circular plates is kept constant, and the pins erected in the vicinity of the circle edge of the circular plate are alternately erected on the left and right circular plates, and the other end of the pin is fixed. There is no configuration.

JP 2009-78796 A JP 2006-69294 A Japanese Patent Laid-Open No. 11-5572

  As described above, in the rubber crawler of Patent Document 1, the tooth portion 32 of the sprocket 30 is engaged with the driving protrusion 24 formed on the crawler main body 34 so that driving force is applied to the rubber crawler. During this engagement, the tooth portion 32 is completely buried in the recess 20 of the crawler main body 34, so that mud, grass, etc. that are bitten between the tooth portion 32 and the recess 20 are repeatedly bitten by the recess 20. In some cases, the tooth portions 32 of the sprocket 30 are not sufficiently engaged, and it is difficult to transmit the driving force to the rubber crawler satisfactorily. In addition, since the tooth portion 32 of the sprocket 30 is always fitted or brought into contact with the concave portion 20 of the crawler main body 34, the number of times of contact with the tooth portion 32 is large, and the concave portion 20 of the crawler main body 34 is formed. There was also concern about heat generation and wear of the rubber members.

  In addition, in the sprocket disclosed in Patent Document 2, since the middle of the pin is vacant, it is difficult for mud or grass to bite, but there is no central part of the pin, so the driving force is transmitted to the driving protrusion. There is a difficulty in doing. Further, in the sprocket of Patent Document 3, since the end portion of the pin is vacant, it is difficult for mud and grass to bite like the sprocket of Patent Document 2, but the center portion of the pin circulates around the drive protrusion. There is a risk of heat generation and wear due to contact each time.

  The present invention has been made in view of the above problems, and the object thereof is to maintain a good engagement state of the sprocket tooth portion with the drive protrusion portion of the crawler body and contact between the tooth portion and the drive protrusion portion. An object of the present invention is to provide a rubber crawler sprocket capable of reducing the area and suppressing the wear and heat generation of the drive projection.

In order to achieve the above object, the rubber crawler according to claim 1,
A circular base portion having a predetermined thickness that is rotationally driven, and a plurality of tooth portions that are formed on the peripheral portion of the circular base portion so as to protrude at a predetermined interval in the circumferential direction. is formed in the radial direction and the thickness direction so as to have a predetermined protruding shape, the driving protrusion on the inner peripheral surface side are formed at predetermined intervals in an endless belt-like crawler body of the rubber crawler, wherein the toothing In sprockets for rubber crawlers that engage and transmit driving force,
The tooth portions are adjacent to each other in the circumferential direction, and the protruding shape in the thickness direction is configured so as not to overlap in the circumferential direction view.

With this configuration, the adjacent protrusions are formed so that the predetermined shape protruding in the radial direction and the thickness direction of the circular base does not overlap with each other in the circumferential direction. There will always be a part that does not come into contact with the part. Therefore, mud, grass, etc. that are bitten between the drive protrusion and the tooth part will be in contact with another part of the drive protrusion part in the next round. The grass and grass are not bitten and fixed, and are easily released, thereby preventing the rubber crawler from being hindered. In addition, since the number of times of contact between the drive protrusion and the tooth portion is reduced, it is possible to suppress wear and heat generation of the drive protrusion. Furthermore, the sprocket can be made lighter than the conventional one.

The rubber crawler sprocket according to claim 2, wherein the rubber crawler sprocket according to claim 1,
The protruding shape of the tooth portion in the thickness direction is formed in a zigzag shape in the circumferential direction. Therefore, the left and right teeth contact the drive protrusions alternately, so that mud, grass, etc. that have been bitten in the previous round are not bitten and are released more easily, hindering the drive of the rubber crawler. Is prevented. Further, since the tooth portions are formed in a zigzag shape, the sprocket can rotate smoothly without losing the balance, and the sprocket can be reduced in weight.

The rubber crawler sprocket according to claim 3 is the rubber crawler sprocket according to claim 1,
The protruding shape in the thickness direction of the tooth portions adjacent to each other in the circumferential direction is a desired shape for transmitting the driving force when viewed in the circumferential direction. Therefore, for example, it is possible to configure the tooth part in two types of shape, a central part and a bifurcated shape on both outer sides of the central part as viewed in the circumferential direction, and the tooth part is adapted to the rubber crawler to be driven. Can be configured. Therefore, it is possible to prevent the rubber crawler from being hindered while maintaining a good driving force of the rubber crawler.

The rubber crawler sprocket according to claim 4 is the rubber crawler sprocket according to any one of claims 1 to 3,
The number of the plurality of teeth formed on the peripheral edge of the circular base is an even number, and the number of the drive protrusions formed on the inner peripheral surface of the crawler body is an odd number. Therefore, the drive protrusions that have contacted the teeth in the previous turn do not contact the teeth in the next turn, and contact in the next turn, which may hinder the driving of the rubber crawler. In addition, heat generation and wear of the rubber member constituting the drive protrusion are prevented, and the life of the rubber crawler is extended.

  According to the rubber crawler of the present invention, when the driving protrusion formed on the inner peripheral surface side of the crawler main body and the tooth portion of the sprocket are engaged, the driving protrusion contacted with the tooth portion is contacted in the previous round. This part will not come into contact in the next round, so mud and grass caught between the drive projection and teeth are prevented from being bitten again, and the rubber crawler is caused by mud and grass being bitten and solidified. In addition, the number of times of contact with the tooth portion is reduced, so that the durability of the rubber crawler is improved, and the traveling machine body can be used for work and the like with confidence over a long period of time.

It is a longitudinal cross-sectional view of a tooth | gear part concerning 1st Embodiment of the sprocket for rubber crawlers of this invention. FIG. 2 is a schematic developed plan view showing a contact portion of a concave portion when the tooth portion of FIG. 1 is engaged with a drive projection portion according to the first embodiment of the rubber track sprocket of the present invention. It is a longitudinal cross-sectional view of a tooth | gear part concerning 2nd Embodiment of the sprocket for rubber crawlers of this invention. FIG. 4 is a schematic developed plan view showing a contact portion of a recess when a tooth portion of FIG. 3 engages with a drive projection portion according to a second embodiment of the rubber track sprocket of the present invention. It is a partial schematic sectional drawing regarding the conventional sprocket for rubber crawlers. However, the state where the tooth portion of the sprocket is engaged with the driving protrusion of the crawler body and the driving force is applied is shown. It is a longitudinal cross-sectional view of a tooth part in connection with the conventional sprocket for rubber crawlers. FIG. 7 is a schematic developed plan view showing a contact portion of a recess when a tooth portion of FIG. 6 is engaged with a driving projection portion in a conventional rubber crawler sprocket.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a longitudinal sectional view of a tooth portion according to a first embodiment of a sprocket for a rubber crawler of the present invention. However, the two types of tooth portions formed on the sprocket are shown in FIGS.

  The crawler body 34 is the same as that shown in the background art. That is, the cored bar 22 is embedded in the circumferential direction of the crawler main body 34 at a predetermined interval in such a manner that the wing portion 22 a extends in the width direction of the rubber crawler 34. A concave portion 20 is formed between the cored bar 22 and the cored bar 22 on the inner peripheral surface side of the crawler main body 34. A pair of protrusions 22b, 22b of the cored bar 22 protrudes inward in the circumferential direction of the crawler body 34, and a pair of drive protrusions 24, 24 are formed by covering a rubber member. In addition, the recess 20 is formed in a substantially rectangular shape on the inner peripheral surface side of the rubber crawler between the core metal 22 and the core metal 22 and in the central portion in the rubber crawler width direction, as shown in the background art. (See FIG. 7 of the background art or FIGS. 2 and 4 described later).

  The sprocket 10 for a rubber crawler according to the present invention has a circular base portion 11 and tooth portions 12a and 12b, and the tooth portions 12a and 12b are formed so as to protrude from the peripheral edge portion of the circular base portion 11 in the radial direction and the thickness direction. The tooth part 12a shown in FIG. 1 (a) has the right half of the longitudinal sectional view of the tooth part 32 (see FIG. 6) shown in the background art, and the tooth part 12b shown in FIG. It has the left half of the longitudinal cross-sectional view of the part 32 (refer FIG. 6). The teeth 12 a and 12 b of the sprocket 10 are alternately provided on the periphery of the sprocket 10 at equal intervals, and engage with a pair of drive protrusions 24 and 24 formed on the inner peripheral surface side of the crawler body 34. .

  FIG. 2 relates to the first embodiment of the rubber crawler sprocket of the present invention, and is a schematic developed plan view showing the contact location of the recess 20 when the tooth portion 32 of FIG. It is. Since the tooth portions 12a and 12b of the sprocket 10 are alternately provided on the peripheral edge of the sprocket 10, the portion that contacts the recess 20 of the rubber crawler 34 is a portion indicated by hatching in FIG. As shown in FIG. 2, the region where the teeth 12a and 12b are in contact with the recess 20 is half of that in the conventional plan view. That is, if the recess 20 is regarded as a part of the drive protrusion 24, the teeth 12a and 12b come into contact with the drive protrusion 24 alternately.

  The sprocket 10 has an even number of teeth 12a and 12b in total, and the number of the pair of drive protrusions 24 and 24 formed on the rubber crawler 34 is an odd number (therefore, the number of the recesses 20 is also an odd number). Therefore, when the right region 20a in the rubber crawler width direction of the concave portion 20 comes into contact with the tooth portion 12a, the left region 20b of the concave portion 20 comes into contact with the tooth portion 12b in the next round. Therefore, each time the crawler body 34 circulates, the concave portion 20 is configured such that the right region 20 a and the left region 20 b are alternately engaged with the tooth portions 12 a and 12 b and a driving force is applied to the driving protrusion 24.

  As a result, even if mud, grass, etc. are bitten, the opposite side of the bite will contact the teeth 16a, 16b in the next round, so mud, grass, etc. bitten in the previous round will be bitten again. Since there is no, there is no bite. Therefore, mud, grass, and the like are easily released, and a state where the mud, grass, etc. are bitten and the driving force is not transmitted well is suppressed.

  Further, if attention is paid to the half region of the concave portion 20 constituting the driving projection 24, the tooth portion 32 has been engaged every time when the crawler main body 34 circulates until now, but the contact area is half. As a result, heat generation and wear of the drive projection 24 are suppressed. Therefore, biting of mud, grass, or the like is prevented, and the durability of the rubber crawler 34 is improved, so that the traveling machine body can be used for work and the like for a long period of time. In addition, the weight of the sprocket 10 can be reduced.

(Second Embodiment)
FIG. 3 is a longitudinal sectional view of a tooth portion according to a second embodiment of the sprocket for rubber crawler of the present invention. However, two types of tooth portions formed on the sprocket are shown in FIGS.

  The rubber crawler sprocket 14 according to the present embodiment has a circular base portion 15 and tooth portions 16a and 16b, and the tooth portions 16a and 16b are formed so as to protrude from the peripheral portion of the circular base portion 14 in the radial direction and the thickness direction. Yes. The tooth portion 16a shown in FIG. 3A has a bifurcated shape in which the central portion in the rubber crawler width direction is cut out in the tooth portion 32 shown in the background art (see FIG. 6), and is shown in FIG. 3B. The tooth portion 16b has a shape that leaves the above-described notched portion. The teeth 16a and 16b of the sprocket 14 are alternately provided on the peripheral edge of the sprocket 14 at equal intervals, and are alternately engaged with a pair of drive protrusions 24 and 24 formed on the inner peripheral surface of the crawler body 34. To do.

  FIG. 4 relates to a second embodiment of the sprocket for a rubber crawler according to the present invention, and is a schematic development showing contact portions of the recess 20 when the tooth portions 16a and 16b of FIG. It is a top view. Since the tooth portions 16a and 16b of the sprocket 14 are alternately provided on the peripheral edge of the sprocket 14, a portion that contacts the concave portion 20 of the crawler main body 34 is a portion indicated by hatching in FIG.

  Specifically, when the concave portion 20 is equally divided into four sections in the rubber crawler width direction in a plan view, the tooth portion 16a comes into contact with the two sections 20d on both outer sides of the central two sections 20c. It is configured. Further, the tooth portion 16b is configured to come into contact with the central two sections 20c of the recess 20.

  Further, the sprocket 14 is formed with an even number of teeth 16a and 16b in total, and the number of the recesses 20 formed in the rubber crawler 34 is an odd number (odd links). When the central two sections 20c are engaged with the tooth portions 16b, the two sections 20d on both outer sides of the two sections of the recess 20 are then engaged with the tooth portions 16a. Therefore, each time the rubber crawler 34 circulates in the recess 20, the central two sections 20c and the two outer sections 20d are alternately engaged with the teeth 16a and 16b, and the driving projection 24 is efficiently driven. Will be applied.

  Therefore, according to the rubber crawler sprocket 14 of the present embodiment, in the concave portion 20 constituting the driving projection 24, the portion where the tooth portions 16a and 16b engage is half in the plan view of the inner peripheral surface of the crawler body 34. Since the area is increased, mud and grass are prevented from being bitten, and the durability of the rubber crawler is improved, so that the traveling machine body can be used for work and the like for a long period of time.

  Further, as compared with the first embodiment, when the tooth portions 16a and 16b apply the driving force to the rubber crawler 34, the driving force can be applied in a balanced manner with respect to the center in the width direction of the crawler body 34. It has become. Further, it can be made lighter than conventional sprockets.

  Note that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, in the first and second embodiments, the crawler body has a pair of drive projections and a configuration in which there is a recess with which the teeth contact, but there is only one drive projection, The present invention can also be applied to a crawler body having no recess.

10, 14, 30 Sprocket 11, 15, 31 Circular base 12a, 12b Tooth (first embodiment)
16a, 16b Teeth (second embodiment)
20 Concave portion 20a Right side region 20b Left side region 20c Central two compartments 20d Two outside two compartments of the central two compartments 22 Core bar 22a Wing portion 22b Protrusion portion 24 Drive projection portion 26 Raised portion 28 Lug portion 32 Tooth portion (background technology)
34 Crawler body A Rotation direction E Grounding surface

Claims (4)

A circular base portion having a predetermined thickness that is rotationally driven, and a plurality of teeth that are formed on the peripheral portion of the circular base portion so as to protrude at predetermined intervals in the circumferential direction;
The tooth portion is formed to have a predetermined protruding shape in a radial direction and a thickness direction of the circular base portion,
In a rubber crawler sprocket in which the tooth portion engages with a driving projection formed at a predetermined interval on the inner peripheral surface side of an endless belt-like crawler body of a rubber crawler, and transmits a driving force.
The sprocket for a rubber crawler, wherein the tooth portions are adjacent to each other in the circumferential direction, and the protruding shape in the thickness direction does not overlap with each other when viewed in the circumferential direction.   2. The sprocket for a rubber crawler according to claim 1, wherein the protruding shape of the tooth portion in the thickness direction is formed in a zigzag shape in the circumferential direction.   The sprocket for a rubber crawler according to claim 1, wherein the protruding shape in the thickness direction of the tooth portions adjacent to each other in the circumferential direction is a desired shape for transmitting the driving force as viewed in the circumferential direction.   The number of the plurality of teeth formed on the peripheral edge of the circular base is an even number, and the number of the drive protrusions formed on the inner peripheral surface of the crawler body is an odd number. Item 4. A sprocket for a rubber crawler according to any one of Items 1 to 3.

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