Abstract: A belt (30) for suspending and/or driving an elevator car (14) includes a plurality of tension elements (32) extending longitudinally along a length of the belt, at least one tension element of the plurality of tension elements having one or more tension element coating layers (46) applied thereto. A plurality of fibers are interlaced with the plurality of tension elements forming a composite belt structure. A belt coating (44) at least partially encapsulates the composite belt structure.

Abstract: A track for a vehicle having a plurality of wheels for driving the track on a terrain. The track has an endless elastomeric carcass having a wheel-facing side that is mountable onto the plurality of wheels, and a ground-facing side opposite the wheel-facing side. A plurality of elastomeric traction surfaces is positioned on the ground-facing side. Each of the traction surfaces has a first shape when the track is not mounted onto the plurality of wheels. A plurality of primary load distribution members is positioned transversely and distributed longitudinally in the carcass so as to distribute at least parts of downward wheel forces applied by at least one of the wheels when the track is being driven down onto the wheel-facing side of the carcass into the traction surfaces via flexion of the primary load distribution members.

Abstract: A track includes a body formed of an elastomeric material having a series of longitudinally spaced guide-drive lugs, as well as a base and an outer surface disposed upon the upper face of each of the guide-drive lugs. At least one multilayer reinforcement is disposed within each of the guide-drive lugs at a distance inward from the outer surface, where the multilayer reinforcement is a contiguous roll providing a plurality of 360-degree turns of reinforcement material, and the roll has an axial cross-sectional shape selected from one of circular, rectangular, square, ovate and trapezoidal.

Abstract: A rubber crawler includes a rubber belt trained around a drive wheel, plural rubber projections that are provided at the rubber belt at intervals along the crawler circumferential direction, that project toward the crawler circumferential inside, that are each formed in a peaked shape widening from an apex portion to a base portion as viewed from the crawler width direction, and that are input with drive force when an engagement pin provided at the drive wheel engages with a circumferential direction rubber wall face, and an embedded member that is embedded in the rubber projections and has a circumferential direction wall face arranged along the circumferential direction rubber wall face as viewed in cross-section along the crawler circumferential direction.

Abstract: A rubber crawler has: an endless rubber belt that is entrained about plural wheels; plural rubber projections that are disposed on the rubber belt and spaced apart from one another in a crawler circumferential direction, project toward an inner peripheral side of the rubber belt, and come into contact with the wheels to limit the movement of the wheels in a crawler width direction; and a low-hardness rubber portion that configures part of an inner peripheral surface of the rubber belt, is disposed between mutually adjacent rubber projections, and is formed by a rubber having a lower hardness than the rubber projections.

Abstract: A rubber crawler includes a rubber belt, a main cord layer that is incorporated within the rubber belt and includes a main cord extending around the crawler circumferential direction, a bias cord layer that is incorporated further to the crawler circumferential outside than the main cord layer and is configured from bias cords extending at an angle with respect to the crawler circumferential direction, a bias cord layer that is interposed between the bias cord layer and the main cord layer, and is configured from bias cords extending at an angle with respect to the crawler circumferential direction so as to intersect the first bias cords, and a reinforcement cord layer that is interposed between the bias cord layer and the bias cord layer, and is configured from reinforcement cords extending in the crawler width direction.

Abstract: A rubber crawler includes a rubber belt, a main cord layer that is incorporated within the rubber belt and includes a main cord configured from plural twisted strands covered with rubber, the main cord extending around the crawler circumferential direction, and a bias cord layer incorporated within the rubber belt at the crawler circumferential outside of the main cord layer configured by at least one bias ply and configured from at least one bias ply that is formed from a plurality of bias cords extending at an angle with respect to the crawler circumferential direction, disposed side-by-side around the crawler circumferential direction and covered in rubber such that bias cords of the bias ply at the circumferential outermost side of the crawler are, as viewed from the crawler circumferential outside, angled toward an opposite side, with respect to the crawler circumferential direction, from the angled side of the strands.

Abstract: A track formed of a molded rubber base sandwiching a cord layer and a single layer of ply fabric extending longitudinally of the track.

Abstract: A rubber track having: an endless rubber elastic body 1; a plurality of cores 2 arranged at predetermined pitches in the rubber elastic body so as to extend in a width direction of the rubber elastic body; a reinforcing layer extending in the rubber elastic body so as to surround the cores 2; and a plurality of lugs 4 formed on an outer peripheral surface of the rubber elastic body 1 at predetermined intervals and acting on a road surface, the rubber track comprising; a thick wall rubber portion, located between the lugs on the outer peripheral surface of the rubber elastic body, that covers an end portion of each of the cores and communicates with lugs located therebefore and thereafter, wherein an inclined plane of the thick wall rubber portion facing obliquely outward whose thickness gradually decreases toward a side edge side of the rubber elastic body is coplanar with an inclined plane of each of the lugs on the side edge side of the rubber elastic body.

Abstract: A rubber crawler which includes: a rubber crawler body having an endless belt shape and which has a left-right pair of rolling wheel passing surfaces on the inner circumferential surface thereof; a steel cord layer in which a plurality of steel cords extending in the crawler circumference direction are embedded in the rubber crawler body so as to be arranged in the crawler width direction, and a plurality of bias reinforcing layers that are disposed on the outer circumferential side of this steel cord layer in the rubber crawler body, in which the left-right pair of rolling wheel passing surfaces are disposed on the inner circumferential surface of the rubber crawler body at positions corresponding to the respective end portions in the crawler width direction of the steel cord layer and the plurality of bias reinforcing layers; the rubber crawler further includes: a rubber layer disposed between an innermost reinforcing layer that is positioned on the innermost side of the plurality of bias reinforcing layers

Abstract: The present invention relates to a rubber crawler having a metal core for improvement of wheel separation and durability, and comprises metal core extensions formed at predetermined intervals along the lengthwise direction of the metal core of the rubber crawler, thereby avoiding the phenomenon of wheel separation which occurs during crawler operation, and minimizing lug breakage due to foreign objects, bend fatigue of a metal core, metal core exposure and breakage of a tread portion, so that the durability performance is enhanced.

Abstract: A coreless rubber crawler track has an endless rubber elastic body (1), steel cords (3) embedded in the longitudinal direction of the elastic body, rubber protrusions (2) formed at a constant interval from the inner peripheral surface toward the longitudinal direction of the elastic body, and rubber lugs formed on the outer peripheral surface. Bias cords (5, 6) are arranged on the outer peripheral side of the steel cords (3) so as to extend to the lateral right and left in the directions opposite from each other. Both bias cords (5, 6) are overlapped on each other over a width of 10 mm or more directly under the rubber protrusions. With such an arrangement, torsional rigidity and lateral rigidity of the rubber crawler track are improved and, even when the rubber crawler track is passed over sprockets etc., bending rigidity is not high and a tooth skip phenomenon is suppressed.

Abstract: A track formed of a molded rubber base sandwiching a cord layer and a single layer of ply fabric extending longitudinally of the track.

Abstract: The present invention relates to a coreless rubber crawler traveling device in which spring characteristics are achieved by reducing a contact area of a wheel-rolling contact surface on an inner peripheral surface of a rubber elastic body with an outer surface of a tracker roller. A coreless rubber crawler comprises an endless rubber elastic body, main cord rows embedded in the rubber elastic body in a longitudinal direction of the rubber elastic body, rubber projections formed on the inner peripheral surface of the rubber elastic body at uniform pitches, and rubber lugs formed on the outer peripheral surface of the rubber elastic body. In the coreless rubber crawler traveling device, a tracker roller, which is provided at the side of a vehicle body and which straddles the right and left sides of each of the rubber projections in the widthwise direction, rolls in such a manner that an outer surface of the tracker roller comes into contact with the inner peripheral surface of the rubber elastic body.

Abstract: A rubber crawler track having less wear at its left and right end portions to improve its durability. The rubber crawler track has steel cords 12 embedded in the longitudinal direction of the track and has a rubber lug 15 formed on the outer periphery side thereof. The rubber crawler track is constructed from three kinds of rubbers that are an inner peripheral side rubber (a), an outer peripheral side rubber (b), and an edge rubber (c) at the left and right of the rubber crawler track. The edge rubber (c) is a rubber layer having the highest hardness degree. The ground contact side, inner peripheral side and ends in the width direction have different kinds of rubber, and the edge rubber (c) having excellent wear resistance with a hardness degree of 72 (JIS A) or greater is placed in particular at the machine body side end of the rubber crawler track because of the significant wear at this location.

Abstract: A highly durable elastic crawler with a tensile cord having both ends thereof overlapped mutually in a crawler body thus being circumferentially wound around the crawler is provided. An elastic crawler includes; a crawler body including an endless belt-like elastic body; metal cores embedded in the crawler body, each of the metal cores including vanes and arranged at predetermined intervals circumferentially; and tensile cords transversely arranged, wound around the outer circumference side of the vanes, and embedded in the crawler body while vicinity portions of both ends of the tensile cords are overlapped mutually. An inner circumference side end is arranged at an outer circumference side of any one of the vanes. The distance between the vicinity portion of the inner circumference side end and the outer circumference side portion of the tensile cord overlapped there is increased from the vicinity portion toward the inner circumference side end.

Abstract: The present invention relates to a crawler used for transporting continuous-track vehicles for construction, civil engineering, agricultural use or the like. More particularly this invention relates to a structure of a tension member of the crawler, in which a plurality of tension members concentrically wound are juxtaposedly inserted in the transverse direction of the crawler, and therefore the tension member is prevented from being delaminated and the durability and the workability and productivity can be more improved. The present invention is characterized in that each of the tension members is concentrically wound several times, and the wound members are arranged juxtaposedly in the transverse direction of the crawler, thereby forming the tension members in the form of plural layers.

Abstract: A track formed of a molded rubber base sandwiching a cord layer, followed by a cross bar and a single layer of ply fabric extending longitudinally of the track.

Abstract: The present invention relates to a crawler without steel cores (hereinafter referred to as “coreless crawler”), which is used for transporting the caterpillar vehicles for construction, civil engineering, agricultural use or the like. More particularly this invention relates to a coreless crawler for preventing the crawler body from being separated from a wheel or sprocket and the guide roller from riding the guide projection formed on the inward surface of the crawler, by disposing a pair of separation preventing steel cords having an oblique angle, symmetrically with respect to the center portion in the direction of driving so as to balance the deflection forces, thereby extending the lifetime of the crawler product.

Abstract: A rubber track (1) has formed in it simple means that can carry a part of abnormal tensile force acting on substantially the entire length in the circumferential direction of the rubber track (1). The construction secures smooth operation of the rubber track and reliably prevents cutting of a steel cord (s1) due to such abnormal tensile force. A core (3) has an engagement section (3b) located in the center region in the longitudinal direction of the core, guide projections (3a) on the outer sides of the guide projections (3a). The core (3) further has tensile force carrying sections (4a, 4b) arranged at positions that are located in the thickness direction of the core and are closer to the outer periphery of the rubber track than the outer peripheral-side d-surfaces of the wing sections (3c). The tensile force carrying sections (4a, 4b) carry tensile force acting in the lateral direction of the core and also carry pressing force acting in the thickness direction of the core.

Abstract: The present invention relates to a crawler without steel cores (hereinafter referred to as “coreless crawler”), which is used for transporting the caterpillar vehicles for construction, civil engineering, agricultural use or the like. More particularly this invention relates to a coreless crawler for preventing the crawler body from being separated from a wheel or sprocket and the guide roller from riding the guide projection formed on the inward surface of the crawler, by disposing a pair of separation preventing steel cords having an oblique angle, symmetrically with respect to the center portion in the direction of driving so as to balance the deflection forces, thereby extending the lifetime of the crawler product.

Abstract: An elastic endless includes an annular belt-shaped elastic crawler body and a plurality of cords with ends, the cords being disposed substantially parallel with one another at predetermined intervals and embedded in the crawler body, wherein one end and the other end of each cord are overlapped, as seen from the belt side.

Abstract: A rubber crawler having a very good straight driving property is obtained by modifying a method of embedding bias cords in a rubber crawler and neutralizing shear stresses caused by tensile load of bent portions of the crawler when the crawler is entrained about a vehicle main body. The rubber crawler is comprised of an endless rubber elastic body, a main cord row, two layers of bias cords having opposite angles of inclination, guide projections, and a lug. The bias cords of the first layer at a side near the main cord row are embedded over a region having substantially the same transverse dimension as that of the main cord row, at a fixed angle of inclination, and the bias cords of the second layer are divided into two sections, covering a region having substantially the same transverse dimension as that of the bias cords of the first layer other than a portions corresponding to the guide projections.

Abstract: The object of the present invention is to provide a coreless rubber which ensures running stability by compensating shift (deviation) in the width direction even if prepared by combination of usual rollers, and which is easily and in low cost prepared by adoption of simple structure.

Abstract: An endless flexible belt track produced from an elastomer comprises a steel cable (30) spirally wound in the thickness of the belt (12) and outer layers embedded in the thickness of the belt and formed successively from the turns (34) of the cable toward the outside, by: a first oblique layer (36) formed from wires that in turn form a first acute angle (A) to a perpendicular to the turns of the cable; a transversal layer (38) formed from wires that in turn form a right angle to the turns of the cable; and a second oblique layer (40) formed from wires that in turn form a second acute angle (B) to a perpendicular to the turns of the cable, the second acute angle (B) extending in the opposite direction to the first acute angle (A). Application to all-terrain vehicles.

Abstract: There is provided an endless track belt laterally reinforced by embedding high elongation cords on each peripheral sides of the endless track belt to prevent cuts formed on the periphery of the belt by sharp objects from propagating further towards the inner width of the endless track belt.

Abstract: An elastic endless crawler including an annular belt-shaped elastic crawler body, the crawler body includes a series of driven elements for operation of the crawler and a reference plane which passes through respective centers of the drive elements and extends in a longitudinal direction of the crawler, and a thickness of one side relative to the reference plane and a thickness of the other side relative to the reference plane are different from one another. The lengths between respective crawler body end surfaces facing in a crawler widthwise direction, and the reference lane are different from one another. A thickness of one side, which is shorter in length, of the crawler body is greater than that of the other side, which is longer in length, of the crawler body.

Abstract: The object of the invention is to provide a rubber crawler which has an excellent driving performance without rubber breakage and a process for manufacturing the same. The object is attained by firstly obtaining a small bending rigidity of a joint part and eliminating disproportional arrangement of main cord embedded in the rubber crawler in a widthwise direction for obtaining durability, and uniform revolution. In a rubber crawler 1 in the form of an endless belt having an inserting joint structure S wherein ends of a number of parallel reinforcing cords 3 as main cords embedded in the rubber crawler are inserted between each other, the number of reinforcing cords are divided in an even number (2 in the embodiments shown with figures) parts, the ends parts 3A1 to 3A6 and 3B1 to 3B6 extending in both directions are arranged axisymmetrically about the dividing line L. Accordingly, the inserting joint structure S is obtained as a prerequisite which is on a same plane when viewed from the side.

Abstract: A rubber crawler includes parallel embedded tensile strength bodies, with each of tensile strength bodies being connected by butt portions. The butt portions of adjacent tensile strength bodies are longitudinally shifted relative to one another in a circumferential direction of the rubber crawler, and at least 75% of the butt portions are positioned on planes of projection of the core bars.

Abstract: An elastic crawler includes a crawler body formed of an elastic material into an endless belt shape; and a tension member including a plurality of tension cords having opposite ends which are embedded in the crawler body so as to extend along a circumferential direction of the crawler and to be arranged in parallel to each other in a widthwise direction of the crawler. The tension member is formed into a loop by overlapping opposite end portions of each tension cord, extremities of the opposite ends of each tension cord of the tension member are aligned diagonally with respect to the widthwise direction of the crawler, and the overlapping width of the overlapped portion of the tension member in the widthwise direction of the crawler is smaller than an entire width of the tension member in the widthwise direction of the crawler at any position in the circumferential direction of the crawler.

Abstract: An elastic endless crawler according to the present invention comprises an annular belt-shaped elastic crawler body and a plurality of cords with ends, said cords being disposed substantially parallel with one another at predetermined intervals and embedded in the crawler body, wherein one end and the other end of each cord are overlapped, as seen from the belt side. Further, at at least one of a crawler inner peripheral side and a crawler outer peripheral side, there are provided a plurality of members for holding the cord ends within the crawler body. As a result, a chance of free ends of embedded steel cords protruding out from the rubber body during use of the rubber crawler and a chance of the rubber crawler running off of a unit for driving for rotation thereof can be eliminated.

Abstract: There is provided an endless track belt laterally reinforced by embedding high elongation cords on each peripheral sides of the endless track belt to prevent cuts formed on the periphery of the belt by sharp objects from propagating further towards the inner width of the endless track belt.

Abstract: A coreless rubber crawler which cancels the difference in the amounts of deformation strains in the main body to improve the durability and which ensures transverse rigidity to prevent coming off of wheels, wherein a peripheral main cord and a reinforcing cord disposed on an outer periphery thereof are embedded in a main body having a thickness T, wherein an embedded depth H of the cord embedded in an outermost peripheral layer of the main body, the depth being measured from an inner peripheral surface of the main body, satisfies H≧½×T.

Abstract: This invention relates to annular or endless elastomeric track 10 for use in vehicles for civil engineering, construction works and agricultural works. The track 10 has a thin belt 20 which includes a primary table 59 made of corrosion resistant galvanized steel. The track 10 further has a plurality of spaced rubber traction tread lugs 30, on the outer surface oriented generally inclined, transverse or substantially perpendicular to the circumferential direction and guide lugs 32 on the internal surface 31.

Abstract: A cover suitable for use in conjunction with a wheelchair wheel. The cover includes a durable nylon fabric and includes a barrier and a cover portion, the barrier being interposed between an inner surface of the cover portion and the tread and sidewalls of the wheel so that foreign matter present on the wheel does not contaminate or otherwise harm any persons or surfaces with which the covered wheel may come into contact. The cover further includes an outer surface and first and second edges. A plurality of straps attached to the first edge of the cover, and configured to be removably attached to the second edge of the cover, permit the cover to be readily attached to, and detached from, the wheel. Finally, a plurality of lateral seams on the outer surface of the cover facilitate traction when the wheelchair passes over relatively smooth surfaces.

Abstract: A rubber crawler which is mounted on a continuous chain tread traveling device, such as an agricultural working vehicle, a civil engineering machine, a construction machine or a transportation vehicle, and designed to improve durability in the connecting section of a tensile strength body embedded therein. A plurality of tensile strength bodies (5) paralleled and arranged in a row widthwise of the rubber crawler (1) along the circumferential direction of the rubber crawler are divided into two along the middle of the rubber crawler. In embedding the two rows of tensile strength bodies in the rubber crawler, the front ends of the opposite ends (5a, 5b) of the individual tensile strength bodies are abutted against each other and connected together into an endless form.

Abstract: In a resilient crawler of this invention, sufficient flexibility at the portion between the lugs is obtained and such problems as separation of rubber are prevented while improving riding comfort by reducing the difference in rigidity between the portion where the lug is formed and the portion between the lugs, and improving lateral rigidity to assure the tractive force. Therefore, a resilient crawler of the present invention comprises a crawler body formed of a resilient material in the shape of an endless belt and having a multiplicity of lugs projecting from the outer peripheral surface at intervals longitudinally along the crawler body; and a multiplicity of linear lateral reinforcing members disposed in the crawler body so as to extend laterally thereof and be arranged longitudinally therealong.

Abstract: In the present invention, cord protruding portions at each of ends of a crawler body are divided into groups such that each group has a protruding length different from those of other groups. The entire cord protruding portions at one end of the crawler body when seen from a direction perpendicular to a belt surface are disposed so as to present a male configuration, and the entire cord protruding portions at the other end of the crawler body are disposed so as to present a female configuration. The lines each connecting ends of cord protruding portions at the ends of the crawler body can be disposed so as to form a configuration that is one of terraced, tiered, and crenellated when seen from a direction perpendicular to a belt surface. When seen from the direction perpendicular to the belt surface, an overlapping portion of steel cords includes two outlines separated from each other in a longitudinal direction of the belt, and each outline includes a bent line.

Abstract: A coreless rubber crawler which cancels the difference in the amounts of deformation strains in the main body to improve the durability and which ensures transverse rigidity to prevent coming off of wheels, wherein a peripheral main cord and a reinforcing cord disposed on an outer periphery thereof are embedded in a main body having a thickness T, wherein an embedded depth H of the cord embedded in an outermost peripheral layer of the main body, the depth being measured from an inner peripheral surface of the main body, satisfies H≧½×T.

Abstract: A rubber crawler includes an endless rubber belt directed around two toothed wheels, whereby in the circumferentrial direction of the rubber belt parallel metal core elements are embedded in the rubber belt and extend in cross direction of the rubber belt and are provided for guiding supporting rolls provided between the toothed wheels, each metal core element includes a guiding for guiding the supporting rolls and a carrier for receiving the guiding, and the carrier and the guiding are made as separate parts and are connected to each other.

Abstract: In a resilient crawler of this invention, sufficient flexibility at the portion between the lugs is obtained and such problems as separation of rubber are prevented while improving riding comfort by reducing the difference in rigidity between the portion where the lug is formed and the portion between the lugs, and improving lateral rigidity to assure the tractive force. Therefore, a resilient crawler of the present invention comprises a crawler body formed of a resilient material in the shape of an endless belt and having a multiplicity of lugs projecting from the outer peripheral surface at intervals longitudinally along the crawler body; and a multiplicity of linear lateral reinforcing members disposed in the crawler body so as to extend laterally thereof and be arranged longitudinally therealong.

Abstract: Disclosed is a track belt for a snowmobile, which comprises a track belt main body, a core body arranged along a longitudinal direction of the track belt main body, reinforcing woven cloths disposed respectively in the outside and inside of the core body, cover layers for covering these reinforcing woven cloths and a plurality of horizontal rigid members placed at specified intervals in the longitudinal direction of the track belt main body and in the cross direction of the same. Overlapping of the reinforcing woven cloth is disposed respectively in the outside and inside of the horizontal rigid members. Reinforcing woven cloth is made by spirally winding a belt-like woven cloth having a specified width on a circumference of the track belt main body at a specified angle to the longitudinal direction of the track belt main body. Reinforcing woven cloths are made of tire fabric cords.

Abstract: Two endless wire rope loops spaced lengthwise of elongated grouser-mounting base plates of a tractor endless tread are secured to the grouser-mounting base plates by spaced U-shaped bows of clamping strips bolted to the grouser-mounting base plates, and the adjacent edges of adjacent clamping strips have interfitting projections and sockets for transmitting shear forces between such adjacent clamping strips.

Abstract: In a rubber crawler, lags are generally are formed on the outer surface of an endless belt-like elastomer, and rubber projections for transmission of driving force and prevention of the rubber crawler from coming of off from a wheel are formed on the inner surface of the elastomer at regular pitches. Rein forcing cord layers are embedded in the elastomer along its longitudinal direction. An abrasion resistant member is embedded in the rubber projection along the width direction of the rubber crawler. Its both end portions are exposed at the sides of the rubber projection. The abrasion-resistant member has a central portion having a small diameter and a pair of end portions connected to the ends of the central portion and having a large diameter. In the exposed portion of the end portion which is exposed at the side surface of the rubber projection, its most interior portion in the radial direction is positioned above the base portion of the rubber projection.

Abstract: Endless loops spaced lengthwise of elongated grouser-mounting plates of a tractor endless tread in which each loop includes two side-by-side stretches of wire rope having the interstices between the strands of both wire rope stretches filled with elastomer material, and both stretches of wire rope being embedded in elastomer material integrating the two stretches into a single embedment, the two wire rope loops being secured to the grouser-mounting plates by spaced U-shaped bends of clamping strips bolted to the grouser-mounting plates, and spacer plates bridge between adjacent grouser-mounting plates and make loose tongue-and-groove joints therewith for enabling the grouser-mounting plates and the spacer plates to tilt relatively as the endless tread travels around a tractor wheel, but the straight tread portion of the tread extending between tractor wheels spaced lengthwise of the tractor is substantially inflexible inward.

Abstract: An elastomeric belt laying vehicle is disclosed for transmitting greater tractive effort to the earth as compared to comparably powered wheel vehicles and being operable at high speed on improved road surfaces without inflicting damage thereto. A pair of the wheels are arranged on each lateral side of the vehicle's chassis for support thereof. An inextensible, endless belt is highly tensioned throughout its length, is entrained about each pair of wheels, and is frictionally, drivingly coupled to at least one wheel of each pair. The structure of the belt, structure of the wheels and cooperating components thereof ensure engagement therebetween, provides long service with minimum maintenance thereof, and supplies the necessary frictional couple to effectively transmit driving torque from the wheels to the belt.

Abstract: An elastomeric belt laying vehicle is disclosed for transmitting greater tractive effort to the earth as compared to comparably powered wheel vehicles and being operable at high speed on improved road surfaces without inflicting damage thereto. A pair of the wheels are arranged on each lateral side of the vehicle's chassis for support thereof. An inextensible, endless belt is highly tensioned throughout its length, is entrained about each pair of wheels, and is frictionally, drivingly coupled to at least one wheel of each pair. The structure of the belt, structure of the wheels and cooperating components thereof ensure engagement therebetween, provides long service with minimum maintenance thereof, and supplies the necessary frictional couple to effectively transmit driving torque from the wheels to the belt.