AU9608198A - An endless belt for use with heavy duty track vehicles - Google Patents

Description

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AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT Name of Applicant: Actual Inventor: CAMOPLAST INC.

Alain LUSSIER

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Address for Service: CULLEN CO., Patent Trade Mark Attorneys, 240 Queen Street, Brisbane, QId. 4000, Australia.

AN ENDLESS BELT FOR USE WITH HEAVY DUTY TRACK VEHICLES Invention Title:

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The following statement is a full description of this invention, including the best method of performing it known to us I1 S S

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*5Oe 0* S. S TITLE OF THE INVENTION AN ENDLESS BELT FOR USE WITH HEAVY DUTY TRACK

VEHICLES

FIELD OF THE INVENTION The present invention pertains to an endless belt for use with a heavy duty track vehicle, such as a crawler-type vehicle, a tractor or equipment having tracks over wheels that provide both ground support and tractive effort.

BACKGROUND OF THE INVENTION The propulsion system found on heavy duty vehicles consists of a pair of longitudinally spaced apart wheel structures which are arranged on opposite sides of the vehicle chassis which is driven by a pair of endless, substantially inextensible belts, each having an inner surface and an outer surface. The inner surface is provided with a series of longitudinally spaced 15 members which guide the track relative to driving and tracking wheels forming part of the wheel structures. The outer surface of the belt is formed of a plurality of longitudinally spaced tread members that provide traction to the vehicle when travelling on various ground conditions.

One such belt structure is illustrated and described in US 20 patent 5,279,378 issued January 18, 1994 to Caterpillar Inc. A similar track is also illustrated and described in US patent 5,005,922 issued April 9, 1991 to Edwards Co.

These endless belts, although inextensible, are subject to bending as they engage the necessary supporting wheels such as drive and 25 idler wheels or rollers. As the belt passes around and contact these wheels, they are subject to stress and it is noted that the greatest stress occurs at the base of the tread member or its junction with the top surface of belt. Belt slitting is also noted whenever the construction of the belt consists of a tread member and a guide member in the same vertical plane.

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55 .555 S S 55 5 S S S S 55 -2- 0@ 0 OBJECTS AND STATEMENTS OF THE INVENTION It is an object of the present invention to provide a geometry to an endless belt of a heavy duty track propelled vehicle which greatly reduces the stress exerted on the belt, especially during its bending occurrence when driven. This is achieved by precisely locating the relative positions of the tread members on the outer surface of the belt to that of the guide members on the inner surface of the track.

The present invention therefore relates to an endless belt for use on a heavy duty track propelled vehicle which comprises: an elongated endless body made of polymeric material body having an outer surface and an inner surface; a plurality of longitudinally spaced guide members integrally formed to the inner surface; two rows of longitudinally spaced tread members integrally formed to the outer surface; the tread members of a first row being longitudinally offset relative to the tread members of the second row; each tread member of the first and second rows having an outer edge area and an inner edge area located at mid-section of the body; each inner edge area of a tread member being in vertical alignment with a corresponding one of the guide members on the inner surface of the body.

In one form of the invention, the tread members define a series of pitches on the outer surface of the track; wherein a pitch is defined as including a tread member of the first row and an adjacent tread member of the second row; and wherein two longitudinally spaced guide members are 25 provided on the inner surface for each pitch of the outer surface.

Other objects, advantages and features of the present invention will become more apparent upon reading of the following non restrictive description of preferred embodiments thereof, given by way of example only with reference to the accompanying drawings.

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-3- BRIEF DESCRIPTION OF THE DRAWINGS: Figure 1 is a perspective view showing a belt made in accordance with the present invention, mounted on idler and drive wheels; Figure 2 is a cross-sectional view taken along lines 2-2 of Figure 3; Figure 3 is a top plan view of the belt; Figure 4 is a cross-sectional view taken along lines 4-4 of Figure 3; and Figure 5 is a side elevational view of the belt.

DESCRIPTION OF PREFERRED EMBODIMENTS Referring to Figure 1, there is shown a wheel structure, generally denoted 10, which may be found on each opposite side of the chassis of a heavy duty track propelled vehicle (not shown). The structure usually includes a rear drive wheel 12, a front idler wheel 14 and a series of 15 track contacting rollers 16, all wheels being included within the loop defined by an endless track or belt 18. Traction to the belt is achieved by a high frictional engagement of the belt with the wheels 12 and 14. The endless belt made in accordance with the present invention comprises an endless elongated body made of polymeric material having an outer surface 20 and an inner surface 22.

The outer surface 20 comprises two rows of longitudinally spaced tread members 26 and 28 that provide traction to the vehicle while the inner face comprises a series of longitudinally spaced guide members o.

which are adapted to provide guiding of the track relative to the wheels of the drive structure. The core of the belt may be reinforced with steel cables and *wires 32 as is conventionnally known.

Referring to figure 2, each tread member 26, 28 has a generally trapezoidal shape; it is defined by a sloping end wall 26a, 28a, adjacent to the outer edges 34 and 36 of the belt, a flat top wall 26b and 28b and opposite generally parallel side faces 26c and 26d, 28c and 28d. The -4tread members define an inner edge area 26', 28' and an outer edge area 26", 28" that extends obliquely relative to the longitudinal plane of the track.

Referring to Figure 2, the guide member 30 is centrally located on the inner surface of the belt and is defined by opposite front and rear faces 40 and 42, opposite side faces 44 and 46 and a rounded lower face 48. Each side face has an inwardly sloping lower section 44' and 46'.

As can be seen in Figure 3, the guide members 20 define a longitudinal mid-section area x "which includes, on the outer surface of the belt, the inner edge areas 26' and 28' of the tread members. An important feature of the present invention is that these areas 26' and 28' extend in a same vertical plane as that of a corresponding guide member 30 located on the inner surface. Referring to figure 5, a pitch of the track is defined on the outer surface of the belt as including one tread member 26 and one tread member 28; there is thus provided, in each pitch, two guide members 0oo S 15 Although the invention has been described above with respect with one specific form, it will be evident to a person skilled in the art that it may be modified and refined in various ways. It is therefore wished to have it understood that the present invention should not be limited in scope, except by the terms of the following claims.

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Claims (4)

1. An endless belt for use with a heavy duty track vehicle comprising: an elongated endless body made of polymeric material, said body having an outer surface and an inner surface; a plurality of longitudinally spaced guide members integrally formed to said inner surface; and two rows of longitudinally spaced tread members integrally formed to said outer surface; the tread members of a first of said rows being longitudinally offset relative to the tread members of a second of said rows; each said tread member of said first and said second rows having an inner edge area located at a mid-section of said body and an outer edge area; each said inner edge area of said tread members being in vertical alignment with a corresponding one of said guide members on said e 15 inner surface of said body.

2. An endless belt as defined in claim 1, wherein said tread members define a series of pitches on said outer surface of said track; wherein a pitch is defined as including a tread member of the first row and ego 20 an adjacent tread member of the second row; and wherein two longitudinally spaced guide members are provided on the inner surface for each pitch of o said outer surface. S*. o

3. An endless belt as defined in claim 2, wherein said inner 25 edge area is defined by opposite parallel side faces and a rounded inner end face; said side faces extending in a plane perpendicular to the longitudinal plane of said endless body. -6-

4. An endless belt as defined in claim 3, wherein said outer edge area of each said tread member extends obliquely from said inner edge area thereof to the outer edge of said body. DATED this 7th day of December 1998 CAMOPLAST INC. By their Patent Attorneys CULLEN CO. 4 b