Rubber crawler
The present invention relates to a rubber crawler including: a joint formed by joining together opposite ends of a crawler body comprising an elastic member shaped like a belt having the opposite ends; and lugs projected at predetermined space intervals along a longitudinal direction of the belt and arranged on an outer circumferential surface of the crawler body. The joint is disposed on the outer circumferential surface of the crawler body, as located in a ground non-engaging portion and at different positions with respect to the longitudinal direction of the belt, the ground non-engaging portion defining an area excluding the lugs. In this way, stress acting on the joint is distributed or reduced.
1. A rubber crawler comprising:
a joint formed by vulcanization joining together opposite ends of a crawler body comprising an elastic member shaped like a belt having the opposite ends; and
lugs projected at predetermined spaced intervals along a longitudinal direction of the belt and arranged on an outer circumferential surface of said crawler body, wherein
said crawler body includes (1) an outer circumferential member constituting the outer circumferential surface thereof (2) and an inner circumferential member disposed on an inner side of the outer circumferential member so as to constitute an inner circumferential surface of the crawler body;
said joint includes (1) an outer circumferential joint portion formed by joining together opposite ends of said outer circumferential member for forming an endless belt shape and (2) an inner circumferential joint portion formed by joining together opposite ends of said inner circumferential member for forming an endless belt shape; and
said outer circumferential joint portion is located in a ground non-engaging portion of the outer circumferential surface of said crawler body and at different positions with respect to the longitudinal direction of the belt, the ground non-engaging portion defining an area excluding said lugs.
2. A rubber crawler according to claim 1 , wherein:
said lugs are separated into left-hand and right-hand lug groups via a portion near a widthwise center of said crawler body or near a sprocket engagement hole and staggeredly arranged in opposing relation; and wherein
said outer circumferential, joint portion is located in said ground non-engaging portion whereas said inner circumferential joint portion is formed substantially along a widthwise direction of said crawler body.
3. A rubber crawler according to claim 2 , wherein:
said lugs are arranged along the longitudinal direction of the belt at a substantially equal pitch; and
said outer circumferential joint portion includes segments, positions of which at widthwise opposite ends of the crawler are shifted from each other along the longitudinal direction of the belt by 0.2 or more times said pitch and 1.5 or less times said pitch.
4. A rubber crawler according to claim 1 , wherein said outer circumferential joint portion includes a portion inclined at 10° or more and 60° or less relative to a widthwise direction of the crawler body as seen in plan viewed from the outer circumferential surface of the crawler.
5. A rubber crawler according to claim 2 , and further comprising:
widthwise reinforcing members embedded at spaced intervals along the longitudinal direction of the belt for the purpose of widthwise reinforcement of the crawler body; and wherein
said inner circumferential joint portion is located substantially centrally of the space between the widthwise reinforcing members.
6. A rubber crawler according to claim 3 , wherein the positions of the segments are shifted from each other along the longitudinal direction of the belt by 0.2 or more times said pitch and 0.8 or less times said pitch.