JPH027751Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention relates to a rubber crawler for vehicles such as agricultural combines and harvesters. By extending the crawler to the necessary limit, cutting of the crawler or any adverse effect on the machine frame is avoided.

[Prior Art] By the way, as shown in Fig. 5, this type of rubber crawler usually has lugs a protruding from the outer surface of the grounding side at predetermined intervals in the circumferential direction, and the width of the crawler body corresponding to the lugs. A core metal is embedded in the rubber substance at the intermediate portion in the direction, and a pair of right and left detachment prevention protrusions b provided on the core metal are made to protrude toward the inner surface of the main body, and a circumference is further provided to surround the core metal row. A tensile reinforcing material such as a continuous steel cord is embedded in the main body in an endless manner, and the crawler is made by boring holes at regular intervals in the circumferential direction between each of the core metals in the middle of the width direction. The teeth of the drive wheel d are engaged with the provided engagement hole c to drive the drive wheel. However, unlike iron track tracks, rubber crawlers have low torsional rigidity, so they may get caught in stones or large clods while running.
Accidents that come off the train are likely to occur when turning, etc.
However, when the wheels come off, the teeth d' of the drive wheel come off the engagement holes c, and the idler wheels e ride on the protrusions b of the metal core, creating abnormal tension in the crawler body. In the event of such an accident, the rubber crawler as a whole must be stretched by 2 to 3% in the length direction along with the internal tensile reinforcement.
In fact, as shown in the graph in Figure 6, when a tensile load is applied to a rubber crawler in the longitudinal direction, the elongation rate is approximately 0.8% under a load of 8000 kg, and the elongation rate is 1%.
Depending on the elongation rate before and after, the tensile reinforcing material may break, the protrusion b of the core bar may break, or the machine frame may be damaged.

Therefore, in Japanese Utility Model Publication No. 62-36695, the present applicant proposed that on both sides of the crawler body, including the portion where the steel cord was embedded as the tensile reinforcing material, the outer surface of the crawler body is provided with a grounding line between the front and rear core bars when viewed from the side. A rubber crawler having a concave inward concave shape, a corresponding inner surface of the main body convexly inward, and a steel cord in the main body curved so as to conform to the concave and convex shape. According to this proposal, when the above-mentioned abnormal tension occurs, the internal steel cord will also stretch in the circumferential direction along with the curved part in the crawler body, thereby preventing the above-mentioned cutting and other accidents. It is possible.

(Problem to be Solved by the Invention) However, according to this conventional example, the curved portion of the main body is formed up to the side end of the main body where the steel cord does not exist, so that the above-mentioned elongation occurs throughout the width direction. This makes it even more likely that a train will fall off the train. This is because rubber crawlers are originally easy to stretch due to the inherent elasticity of rubber, and accidents that occur when the wheels come off are caused by creating a lengthwise margin in the steel cord, which is difficult to stretch, and the surrounding rubber parts. This can be sufficiently prevented by making the crawler body stand upright.For this reason, if the curved portions are formed all the way to both ends of the crawler body,
This is undesirable because unnecessarily elongation tends to occur, which in turn increases the likelihood of wheel derailment.

In order to deal with this problem, the present invention does not uniformly form the uneven curved portions between each of the core metals all the way to both ends, but instead forms the curved portions between the steel cords and the surrounding area where the cords are buried. This can be realized by forming the curved portion in the wing portion of the crawler main body outwardly from the curved portion, and forming the curved portion gradually shallower toward both ends so as to disappear at both ends.

[Means for solving problems]

That is, the present invention has a crawler body which is formed into an endless shape from an elastic material such as rubber, and has lugs integrally protruding from the outer surface of the grounding side at predetermined intervals. A core metal has a pair of right and left anti-removal protrusions that protrude along the inner surface in accordance with the protruding position, and endless steel cords are embedded in the circumferential direction to surround both sides of the core metal. In the rubber crawler, the outer surface of the grounding edge is concave when viewed from the side, and the inner surface corresponding to the outer surface of the core bar in the central part of the crawler body where the steel cord is buried, except between the left and right detachment prevention protrusions, is concave. is a convex wavy curved portion, and the steel cord is curved approximately along the curved portion, and the curved portion is curved at both wing portions of the crawler body so that it disappears at the side ends. It is characterized by being formed so that it becomes gradually shallower toward the end.

[Effect]

In the rubber crawler of the present invention, in the running state shown in FIG. When the crawler body rides on the protrusion b of the core metal and comes off the track, the abnormal tension generated in the longitudinal direction causes the crawler body to bend the curved part of the internal steel cord into the uneven curved part around the reinforcing material. By stretching the crawler body, which includes a rubber part that is curved, a main body wing part that is provided so that the curved part becomes shallower toward both ends, and both ends that are straight in the front-rear direction, the abnormal tension can be alleviated. By mitigating this, it is possible to prevent accidents such as the crawler or steel cord breaking or having a negative impact on the machine frame.

〔Example〕

Next, the present invention will be explained with reference to the embodiment shown in the figure.
In FIGS. 1 to 4, 1 is an endless crawler body made of an elastic material such as rubber, and 2 is a lug provided on the outer surface of the grounding side of the main body 1 at predetermined intervals in the circumferential direction. The main body 1 has a main body central portion 5 including a row of core metals 3 buried in parallel in the circumferential direction within the rubber substance corresponding to the lugs 2, and a main body center portion 5 including a steel cord 4 buried so as to surround the core metal rows. It consists of an extended wing section 6. Reference numeral 7 denotes a detachment prevention protrusion formed as a pair on the left and right sides of the core bar 3, which protrudes along the inner periphery of the central part 5 of the main body, and 8 indicates a drive wheel projection formed at the widthwise middle part of the main body 1 between the core members. This is an engagement hole for engaging teeth. As shown in Fig. 4, the lugs 2 are of two types, one long enough to extend across the entire width of the main body 1, and the other short enough to roughly correspond to the width of the central part 5 of the main body. However, the length, shape, and pattern of the lugs can be freely selected. 9 is a concave outer surface of the grounding edge when viewed from the side in the central part 5 of the main body between the front and rear of each core bar 3 except between the left and right detachment prevention protrusions 7, 7, and a corresponding inner surface is concave. The steel cord 4 is curved 9' approximately along this curved part, and the curved part is formed at both ends 1' of the crawler body 1. The side edges of the wing portion 6 are formed to become gradually shallower so as to disappear.

〔effect〕

When using the rubber crawler of the present invention, if a derailment accident occurs for some reason, the steel cord, which is originally difficult to stretch, is bent so as to roughly follow the surrounding uneven and wavy curved parts, so that both parties can The steel cord stretches in sync with the crawler body without slipping or peeling, thereby preventing cuts and other accidents.Moreover, both wings of the main body where the steel cord does not exist are necessary. Therefore, unlike the case where a curved part is formed over the width from both wing parts to the side end, it is possible to suppress the occurrence of easy derailment. be. Furthermore, when using the present invention, on muddy ground such as wet rice fields, more mud can be trapped in the concave curved part of the outer surface of the grounding edge, so the height of the lug can be substantially increased accordingly. At the same time, since this curved part disappears at the side edge, it prevents the trapped mud from escaping outward, thereby increasing the traction force on the wet field as much as possible. It is played.

[Brief explanation of drawings]

Figure 1 is a plan view showing the cut end and inner surface of the rubber crawler of the present invention, Figure 2 is an enlarged side view, Figure 3 is an enlarged side view,
Figure 4 is a cross-sectional view taken along lines A-A and B-B in Figure 1, Figure 5 is a side view showing an example of how a normal rubber crawler is used, and Figure 6 is a longitudinal tensile load applied to the rubber crawler. It is a graph showing the limit of the actual elongation rate. 1 is the crawler main body, 2 is the lug, 3 is the core metal, 4
5 is a tensile reinforcing material, 5 is a central part of the main body, 6 is a wing part, 7 is a protrusion of a metal core, and 9 and 9' are curved parts.

Claims (1)

[Scope of utility model registration request] The crawler body is made of an elastic material such as rubber and has an endless shape, and lugs are integrally protruded at predetermined intervals from the outer surface of the ground contact surface.The crawler body has lugs protruding from the outer surface thereof at predetermined intervals, and corresponds to the protruding positions of the lugs within the rubber substance at the middle part in the width direction. In a rubber crawler, a core metal has a pair of right and left detachment prevention protrusions protruding from the inner surface thereof, and a steel cord having an endless shape in the circumferential direction is embedded in each side so as to surround both sides of the core metal. When viewed from the side, the outer surface of the grounding edge between the front and back of each core bar in the central part of the crawler body in which the steel cord is buried, except for the areas between the left and right detachment prevention protrusions, is made concave, and the corresponding inner surface is made convex. The steel cord has a wavy curved portion, and the steel cord is curved approximately along the curved portion, and the curved portion is gradually bent toward the side edges of both wing portions of the crawler body so that the curved portion disappears at the side edges. A rubber crawler characterized by being formed to be shallow.