EP0179567B1 - Demolition and compaction track shoe and assembly for crawler vehicle - Google Patents

Abstract

A demolition and compaction track shoe and assembly for a crawler vehicle includes a central opening (21) and downwardly protruding diagonally oriented demolition blades (28,29) cooperating with transversely oriented grouser blades (22,23). The demolition blades provide support to the shoe intermediate the grouser blades to thereby give a smoother ride. The central opening allows material compacted behind the shoe to escape and channels between the grouser and demolition blades allow such material to discharged from the shoe during the non-ground-engaging part of the track cycle. The invention has application to land fill operations and in agriculture where stubble is to be broken up prior to discing.

Description

• This invention pertains to crawler type vehicles and more particularly to an improved cyclic track assembly for same suitable for demolition and compaction of fill materials such as earth, debris, solid wastes, trash, etc.
• Previously, wheeled vehicles having special compacting feet have been used in compacting sanitary land fills, dumps, construction sites, etc. Also, track type tractors using tracks designed solely for tractive purposes have been used for this purpose. Such vehicles have had certain limitations. For example, they have had difficulty in effectively demolishing large rocks, pieces of concrete, etc., as encountered at construction sites Also, when compacting "wet" materials using the usual track type tractor, it has been observed that the materials become impacted behind the track shoes so as to tighten the tracks unduly.
• Further, in compacting fill materials such as trash and earth at a sanitary land fill site, it has been found to be more efficient if the trash is demolished prior to or during compaction of the fill materials so that smaller debris can be compressed into the earth.
• In addition, where corn stubble has been left in a field after harvesting, wheel-style compactors have a limited ability to break up the stubble prior to discing the stubble into the ground. Since burning of stubble has been prohibited in many areas it must now be disced into the ground.
• A crawler vehicle equipped with track shoes or pads as disclosed herein readily serves to break up the stubble even more thoroughly than when using only the disc.
• Thus, there has been a need for an improved compactor for use on sanitary land fills, transfer stations for garbage, and for construction and demolition sites.
• It is known from GB-A 203 617 to provide an opening through the tread surface and from US-A 3 355 225 to provide diagonally extending blades separated by a gap to prevent accumulation of debris.
• According to the present invention there is disclosed a crawler vehicle for use in compacting a fill of earth and debris, the vehicle being of a type supported by spaced parallel endless tracks in which the tracks include a plurality of articulated links supporting track shoes, said shoes each comprising a broad, rigid plate having top and bottom surfaces, a substantial region of the bottom surface acting as a tread surface for engaging the ground, a relief opening formed to extend centrally through said tread surface, said opening being sufficiently large to readily pass fill materials outwardly therethrough to inhibit buildup of impacted materials on the back side of said track shoes and blade means carried to protrude generally normal to said tread surface of said track shoes, characterised by the blade means comprising a pair of grouser blades and a pair of demolition blades said demolition and grouser blades being disposed to define escape channels therebetween for readily permitting material discharged from said opening to freely leave the track shoe.
• Preferably said pair of grouser blades respectively extend along a substantial portion of the leading and trailing edge margins of said tread surface, said grouser blades being mutually offset laterally to opposite sides of the centerline of the path of movement of the track shoes, and said pair of demolition blades extend diagonally substantially in parallel relation respectively from the leading and trailing edge margins of said tread surface toward said trailing and leading edge margins for demolishing debris, said demolition blades being spaced from said grouser blades to define said channels for passing the material discharged from said opening free of said track.
• Preferably the demolition blades are disposed to substantially continuously support said shoes in the region extending between said grouser blades as the shoe progressively engages the ground to enhance stability of said track.
• Preferably the pair of demolition blades extend diagonally of said path, an end of each of said demolition blades invading the plane of an associated grouser blade, the other end of each of said demolition blades extending substantially through an imaginary plane common to each of said other ends, said imaginary plane being disposed substantially normal to said path and intermediate said pair of grouser blades.
• An object of the invention is to provide an improved compactor vehicle wherein the tread reduces the fill materials (such as concrete blocks, rocks, solid waste, etc.) before it grinds them into the ground.
• Another object of the invention is to provide a compactor vehicle having crawler tracks which "run clean", i.e., remain substantially free of any significant impacted buildup of fill material behind or in the tread.
• Yet another object of the invention is to provide an improved crawler track which enhances stability and smoothness of operation of the compaction vehicle. Particular embodiments of the invention will now be disclosed by way of example only and with reference to the accompanying drawings of which;
• Figure 1 shows a diagrammatic perspective view of the leading end of a crawler track, according to the invention;
• Figure 2 shows a diagrammatic perspective view of a track type vehicle supported by track assemblies according to the invention;
• Figure 3 shows an enlarged detail perspective view of a track shoe according to the invention;
• Figures 4 and 5 respectively show bottom plan and end elevation views of a track shoe according to the invention and inverted as when out of contact with the ground;
• Figure 6 shows a diagrammatic representation of the passage of debris from behind the track shoe and away from the tread surface;
• Figure 7 shows a diagrammatic side elevation view of a track assembly for the vehicle in Figure 2; and
• Figure 8 shows a diagrammatic plan view of two links coupled in tandem taken from the track assembly of Figure 7.
• Acrawler vehicle 10 for use in compacting a fill of materials, such as earth and debris, employs a pair of spaced parallelendless track assemblies 11, 12, shown in greater detail in Figures 1 and 7.Track assemblies 11, 12 include a plurality of articulatedlinks 13 coupled in tandem to form an endless or cyclic "belt".Links 13support track shoes 14 secured thereto by means ofbolts 16.
• Vehicle 10 uses its tracks to demolish and compact a fill of materials such as earth and debris, rocks, refuse, etc.
• Eachshoe 14 comprises substantially a rigidrectangular plate 17.Plate 17, for purposes of explanation, includes a top and abottom surface 18, 19 respectively (Figures 4, 5). As used herein the term "bottom" surface pertains to that surface which acts as a tread surface for engaging the ground asvehicle 10 is moved. It will be readily evident, however, that the "bottom"surface 19, when inverted, (as in Figures 4 and 5) becomes a "top" surface during a substantial portion of its cyclic travel.
• A relief opening 21 in the form of a relatively large trapezoidal shaped opening extends centrally throughshoe 14.Opening 21 is sufficiently large to readily release fill material outwardly therethrough so as to inhibit the buildup of compacted materials behindshoe 14.
• As shown, for example, in Figure 5 the leading or left-hand edge 19b curves slightly downwardly so as to slide under thetrailing edge 19c of ashoe 14 preceding it intrack assembly 11. The leadingedge margin 24 ofplate 17 serves to provide a closure between shoes disposed in tandem alongtrack assembly 11. Accordingly, as theshoes 14 travel a horizontal stretch of their path,edge margin 24 will be disposed beneathtrailing edge 19c of a precedingshoe 14. The remainder of the bottom surface ofshoe 14 provides a substantial region for engaging the ground referred to herein as the "tread" surface. Thus, as shown in Figure 4 the region defined within the dimensions x, y comprises the tread surface.
• A drive sprocket 44 engageslink pins 46 to move the track assembly. The sprocket points are aligned to pass directly beneath opening 21 whereby they can assist in urging impacted material out of opening 21.
• As theshoes 14 travel around the ends of their cyclic path,edges 19b and 19c of adjacent shoes move to open and close a gap therebetween. This action as well as that of the drive sprocket 44 causes impacted materials to be urged outwardly through opening 21.
• A pair ofgrouser blades 22, 23 carried from the bottom surface ofshoe 14 protrude generally normal to the tread surface and respectively extend transversely ofshoe 14 along a substantial part of the extent of the leading and trailing transverse edge margins, 26, 27 of tread surface x, y.Grouser blades 22, 23 are mutually offset laterally to opposite sides of the centerline of the path of movement oftrack shoes 14 for reasons described further below.
• In addition,bottom surface 19 carries a pair ofdemolition blades 28, 29 which also protrude generally normal to the region of tread surface x, y.Blades 28, 29 extend diagonally substantially in parallel relation respectively from the leading andtrailing edge margins 26, 31 toward the trailing and leadingedge margins 31, 26 respectively for purposes of demolishing debris while permitting any impacted material emerging from opening 21 to freely leave the track.
• Grouser 22 includes atapered fillet 22a which serves to strengthenplate 17 in the region of the leadingedge 21 a of opening 21 and the openings (not shown) forbolts 32.
• The bolt holes and theelongate edge 21 a cause the adjacent portion ofplate 17 to be the weakest portion. This weakening of a leading portion ofplate 17 has thereby been stiffened by the inclusion of thetapered fillet 22a.
• Both ofblades 22, 23 extend only part way across the full width, y, ofshoe 14 and are mutually offset to opposite sides of the centerline of the path of its associated track. Eachdisplacement 33, 34 (Figure 4) respectively defined between the laterally inner ends of an associatedgrouser blade 22, 23 and aside edge 36, 37 of the rigid plate includes agap 38, 39 respectively defined between the laterally inner end of an associated grouser blade and a portion of a demolition blade invading the plane of the grouser blade.Gaps 38, 39 serve tochannel debris 42 away fromshoe 14. Additional gaps or channels for debris to fall through are indicated at 38' and 39'.Demolition blades 28, 29 lie mainly behind an associated one ofgaps 38, 39 in the path offill materials 42 passing therethrough.
• Assuming that Figure 6 represents atrack shoe 14 moving upwardly in the direction ofarrow 43 as the vehicle moves in a reverse direction, i.e., as the track assembly is viewed from in front, impacteddebris 42 in back ofshoe 14 will be shaken loose by the relative movement betweenshoes 14 as they move around the end of their cyclic path as well as by the action of thedrive sprocket 44.
• Asshoe 14 travels upwardlychannels 38, 38' permit the looseneddebris 42 to pass freely fromshoe 14 by gravity.Channels 39, 39' perform this function when the track moves in a forward direction.
• Thus, as noted above, the tracks are designed to run "clean" so as to rid themselves of refuse and other fill materials rather quickly. For a demolition and compaction vehicle, use of the crawler style tracks further enhances this feature inasmuch as the shoes are drawn apart as they pass around the ends of the track. In this manner the tracks further tend to release material. This "track break" between consecutive shoes opens up a slot between shoes giving entrapped debris an opportunity to fall out. Further, by reducing the material in size before grinding it into the ground, the vehicle described above achieves compaction by a substantially different technique than previously.
• It has been observed thattrack shoes 14 of the kind described serve to provide an improved and enhanced stability and smoother ride. Accordingly,shoe 14 includes means protruding therefrom to form a substantially continuous support beneathplate 17 in the region extending betweengrouser blades 22, 23. Thus, as each tread surface progressively engages the ground, it will be continuously supported fromgrouser 22 togrouser 23.
• As shown best in Figures 1 and 3, and as indicated byarrow 43, as the track moves forward (for purposes of explanation) the leadinggrouser blade 22 will be the first to strike the ground. At substantially the same time, theleading end 28a ofdemolition blade 28 will make contact with the ground followed bydemolition blade 29. Ultimately,grouser blade 23 engages the ground and the entire shoe will then be in a substantially horizontal downwardly facing position while moving along the bottom reach of its track.
• This progressive contact and continuous support beneath each shoe serves to eliminate much of the instability previously noted and causes the vehicle to ride more smoothly.
• More particularly, oneend 28a, 29a of each ofdemolition blades 28, 29 invades the plane defined by an associated one of the twogrouser blades 22, 23 respectively. Theother end 28b, 29b of each ofblades 28, 29 extend substantially beyond an imaginary plane 41 common to each of theends 28b, 29b, and disposed substantially to the path of an associated one of thetracks 11, 12. Plane 41 lies between the pair ofgrouser blades 22, 23.
• It has been observed that the use of acompaction vehicle 10 of the kind described characterized by the demolition blades and shoe design provides enhanced reduction of concrete blocks, rocks, wood products and the like encountered at building sites so that the debris material is reduced in size merely by driving the vehicle back and forth across the debris.
• It has further been observed that a vehicle equipped with tracks of the kind described achieves the desired results more quickly than previously whereby the machine actually is called upon to work fewer hours with attendant fuel and labor savings.
• The smoother ride created by the diagonal segments prevents the machine from rocking and falling from one grouser to the next and enhances the comfort of the operator as well as reducing metal fatigue and machine damage.
• Finally, it has been noted that in many farming communities it is unlawful to burn corn stubble so that farmers in such areas are required to disc the corn stubble back into the ground. The crawler vehicle described above can break up such corn stubble prior to discing so as to achieve a more thorough discing. Further, this can be done all at once if the vehicle tows a disc through the field.
• It has further been observed that since theshoes 14 are carried by conventional track links 13,shoes 14 can be employed together with conventional shoes of the type used on track-type tractors. For example,shoe 14 can be alternated with a standard shoe as desired at the expense of a commensurate loss in function and efficiency.
• According to one method of operation, after first reducing debris material in size, tracks 11, 12 can be driven in opposite directions onto the debris and in this manner virtually "screw" the material into the ground.

Claims (6)

1. A crawler vehicle for use in compacting a fill of earth and debris, the vehicle being of a type supported by spaced parallel endless tracks in which the tracks include a plurality of articulated links (13) supporting track shoes (14), said shoes each comprising a broad, rigid plate (17) having top and bottom surfaces (18, 19), a substantial region of the bottom surface (19) acting as a tread surface for engaging the ground, a relief opening (21) formed to extend centrally through said tread surface, said opening being sufficiently large to readily pass fill materials outwardly therethrough to inhibit buildup of impacted materials on the back side of said track shoes and blade means carried to protrude generally normal to said tread surface of said track shoes, characterised by the blade means comprising a pair of grouser blades (22, 23) and a pair of demolition blades (28, 29) said demolition and grouser blades being disposed to define escape channels (38, 39) therebetween for readily permitting material discharged from said opening to freely leave the track shoe.

2. A crawler vehicle according to claim 1 characterised in that said pair of grouser blades (22) respectively extend along a substantial portion of the leading and trailing edge margins (26, 27) of said tread surface, said grouser blades being mutually offset laterally to opposite sides of the centerline of the path of movement of the track shoes, and said pair of demolition blades (29) extend diagonally substantially in parallel relation respectively from the leading and trailing edge margins of said tread surface toward said trailing and leading edge margins for demolishing debris, said demolition blades being spaced from said grouser blades to define said channels for passing the material discharged from said opening free of said track.

3. A crawler vehicle as claimed in claim 2 wherein each of the grouser blades extends from an end of one of said edge margins along a substantial portion thereof and terminates sufficiently short of the other end of said one edge margin to define a gap therebetween for fill materials to pass therethrough, each said demolition blade being disposed to lie mainly behind its associated said gap and in the path of fill materials emerging from said central opening said demolition blades serving to direct fill materials via said gap.

4. A crawler vehicle as claimed in any preceding claim wherein said demolition blades are disposed to substantially continuously support said shoes in the region extending between said grouser blades as the shoe progressively engages the ground to enhance stability of said track.

5. A crawler vehicle as claimed in any preceding claim wherein the demolition blades (28, 29) extend diagonally of the track path, an end of each of said demolition blades invading the plane of an associated grouser blade, the other end of each of said demolition blades extending substantially through an imaginary plane common to each of said other ends, said imaginary plane being disposed substantially normal to said path and intermediate said pair of grouser blades.

6. A crawler vehicle as claimed in any preceding claim wherein the grouser blade (22) which extends along the leading edge margin includes a tapered fillet (22a) for strengthening the plate in the region of a leading edge (21 a) of the opening (21).

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