EXCAVATING MACHINE FOR ROCKY AND OTHER SOILS

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority from copending provisional patent application

entitled "Excavating Machine for Rocky and Other Soils," serial number 60/634,323 filed

December 8, 2004. The disclosure of provisional patent application serial number 60/634,323 is

hereby incorporated in its entirety.

BACKGROUND OF THE INVENTION

[0002] The invention relates generally to excavating machines of the type having a device

for cutting the earth including bucket wheel trenchers, chain bar trenchers, trencher or trenchless

plows and hoes, vibratory plows, disc wheel cutters, drum cutters, etc., and more particularly to

a cutting plate carried on the trenching wheel or chain for breaking through rocky soils.

[0003] Excavating machines are well known for use in the cutting of an open trench

having either vertical or sloped walls for the purposes of land drainage and irrigation including

agricultural tiling, as well as the installation of utilities such as cable lines, pipelines, water lines,

sewer lines, etc. These excavating machines are often of a vehicular type being self-contained

and suitably driven for either over-the-road travel or movement during use of the earth cutting

device.

[0004] Existing excavating machines usually employ earth cutting buckets or shovels for

cutting into the earth and removing spoil from the trench being made but these elements do not

function well when rocks within the earth to be trenched are encountered. Circular saws have

been utilized for cutting through rocky soils but these machines do not effectively excavate spoil

from a trench. In addition, most trenching excavators are mounted on crawler tractors and are of

very large mass and cannot be driven on hard surface roadways without damage to the roadway

being traversed.

[0005] A need exists for a trench excavator which can penetrate rocky soils, as well as

soils which are sandy or otherwise not populated with rocks, while simultaneously effectively

removing spoil from the trench.

SUMMARY OF THE INVENTION

[0006] The present invention provides a wheel excavating machine which includes a series

of spaced apart plates mounted on the periphery of the wheel. Each plate is provided with one or

more ripping teeth or spikes which extend outward from the plates, with succeeding plates on the

wheel having the spikes arranged in a pattern which is offset from the placement of the spikes on

the adjacent plates. The spikes are directed outwardly in the direction of rotation of the

excavating wheel such that on the spikes are driven against and into the soil wall. In addition,

the plates mounted on the periphery of the wheel may contain spade members which extend from

a leading edge of each plate and are angled slightly outward from the center of the excavating

wheel to claw at softer soils and ground rocks which have first been attacked by the spikes.

[0007] The excavator is equipped with an L-shaped lifting arm to which the excavating

wheel assembly is mounted which allows the excavating wheel assembly and associated shoe

member to be raised or lowered at the rear of the drive unit or tractor. The L-shaped lifting arm

allows downward force to be applied to the wheel assembly. A transverse conveyor is located

within the circumference of the wheel such that spoil carried over the top of the wheel may drop

on the conveyor and be moved to the side of the trench being excavated. A cleaning member

with a cleaning face is located at the top of the digging wheel in such a manner that it removes

the spoil which has accumulated in the rim structure of the digging wheel and directs the spoil

downwardly onto the conveyor.

[0008] A shoe member follows the trenching wheel through the trench being excavated.

The shoe member in cooperation with the L-shaped lifting arm provides a fulcrum for downward

force placed on the L-shaped arm by hydraulic cylinders, thereby forcing the excavating wheel

into the trench and reducing the mass of the drive tractor needed to hold the wheel in the trench.

The drive unit is carried on wheels with tires which permit the machine to be transported under

its own drive power on a roadway.

[0009] Accordingly, it is an object of the present invention to provide an excavating

machine which can trench through rocky soil as well as through non-rocky soil.

[0010] It is a further obj ect of the present invention to provide an excavating machine

which can be operated more efficiently.

[0011] It is also an object of the invention to provide an excavating machine which can

be driven at reasonable roadway speeds on hard surface roadways.

[0012] An additional object of the present invention is to provide an excavating machine

which efficiently removes spoil from the trench being excavated.

[0013] Other features and advantages of the present invention will become apparent upon

a review of the following description, drawings and claims.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)

[0014] FIG. 1 is a front elevational view of an excavating machine in accordance with

the present invention with its ground cutting means in a raised position;

[0015] FIG. 2 is a front elevational view of the excavating machine shown in FIG. 1 with

its ground cutting means at ground level;

[0016] FIG. 3 is a front elevational view of the excavating machine shown in FIG. 1 with

its ground cutting means partially below ground level;

[0017] FIG. 4 is a front elevational view of the excavating machine shown in FIG. 1 with

its ground cutting means at the bottom of a trench;

[0018] FIG. 5 is a top perspective view of an L-arm assembly in accordance with the

present invention;

[0019] FIG. 6 is a bottom perspective view of the L-arm assembly shown in FIG. 5;

[0020] FIG. 7 is a top perspective view of the L-arm assembly showing a slidable leg

member in its extended position;

[0021] FIG. 8 is a top perspective view of the L-arm assembly shown in FIG. 7 showing

the slidable leg member in its retracted position;

[0022] FIG. 9 is a front elevational view of the supporting frame assembly and the wheel

assembly of the excavating machine shown in FIG. 1;

[0023] FIG. 10 is an end plan view of the rim assembly of the cutting wheel assembly in

section with an engagement plate mounted thereto;

[0024] FIG. 11 is a top perspective view of an exemplary plate member showing the

ripping teeth and spades mounted thereto;

[0025] FIG. 12 is a section view of the plate member of Fig. 11 taken along line 12-12 of

Fig. 11.

[0026] FIGS. 13A and 13B are diagrammatic views of a series of plate members mounted

to the rim structure, shown partly cut away, of the wheel assembly of the excavating machine.

[0027] FIG. 14 is a perspective of a deflecting member of the invention carried on a

support member.

[0028] FIG. 15 is a partial cross-sectional elevational view of the wheel assembly shown

in FIG. 9 taken along lines 15-15;

[0029] FIG. 16 is a front elevational view of an alternative cleaning member and wheel

frame assembly in accordance with the present invention;

[0030] FIG. 17 is a top perspective view of a conveyor assembly in

accordance with the present invention, with most of the endless conveyor belt removed;

[0031] FIG. 18 is a bottom perspective view of the conveyor assembly shown in FIG. 17;

[0032] FIG. 19 is a cross-sectional view of the endless conveyor belt shown in FIG. 17

taken along lines 19—19;

[0033] FIG. 20 is a cross-sectional view of the endless conveyor belt shown in FIG. 17

taken along lines 20-20;

[0034] FIG. 21 is a side elevational view of a shoe assembly and an adjustable groover

assembly in accordance with the present invention;

[0035] FIG. 22 is a sectional front elevational view of the shoe assembly

and the adjustable groover assembly shown in FIG. 21 taken along lines 22—22;

[0036] FIG. 23 is a top perspective view taken from the rear of the adjustable groover

assembly and a mounting assembly shown in FIG. 21 ;

[0037] FIG. 24 is a top perspective view taken from the front of the adjustable groover

assembly and the mounting assembly shown in FIG. 21;

[0038] FIG. 25 is a top perspective view taken from the rear of the adjustable groover

assembly shown in FIG. 21 in its closed position; and

[0039] FIG. 26 is a top perspective view taken from the rear of the adjustable groover

assembly shown in FIG. 21 in its open position.

DETAILED DESCRIPTION OF THE INVENTION

[0040] This invention discloses an improved excavating machine for cutting a trench

through the earth. The invention particularly discloses an improved excavating machine for

trenching through rocky soils. Prior improvements to wheel trenchers invented in whole or in

part by one of the instant inventors are shown in U.S. Patents Nos. 4,890,670; 5,873,186;

5,943,798; and 6,055,750; the disclosures of each of which are incorporated herein by this

reference.

[0041] Referring to Fig. 1, the numeral 30 generally designates the excavating machine of

the present invention. The excavating machine 30 includes a power unit vehicle 32 supported by

wheels 34. Pivotally mounted about a horizontal axis 35 on the power unit vehicle 32 is an L-

arm assembly 36 which is adapted to be raised and lowered by means of a hydraulic cylinder 38.

Pivotally mounted to the L-arm assembly 36 is earth cutting assembly 40. The earth cutting

assembly 40 of the preferred embodiment comprises a rock wheel trencher assembly 42 and a

supporting frame assembly 44. The supporting frame assembly 44 is pivotally mounted about a

horizontal axis 46 as part of a means for controlling the pitch of the earth cutting assembly 40,

and this pivotal movement is controlled by a second hydraulic cylinder 48. Rotatably mounted to

the supporting frame assembly 44 is a wheel assembly 50. Also mounted to the supporting frame assembly 44 are a conveyor assembly 52 and a shoe assembly 54.

[0042] Figs. 1-4 schematically show the excavating machine 30 in its range of positions.

Fig. 1 shows the excavating machine 30 with earth cutting assembly 40 raised to its highest

position, when machine 30 is ready for movement to a new site. Fig. 2 shows the earth cutting

assembly 40 lowered to ground level 55. Fig. 3 shows the earth cutting assembly 40 partially

below ground level 55 as a trench 56 in rocky ground or solid rock 58 is begun. Fig. 4 shows the

earth cutting assembly 40 in a position at the bottom 59 of the trench 56 in the ground 58.

[0043] Figs. 5-8 show the L-arm assembly 36 for raising and lowering the earth cutting

assembly 40. The L-arm assembly 36 is located between the power unit vehicle 32 and the earth

cutting assembly 40. The L-arm assembly 36 includes a first arm 60 having a first end 62 and a

second end 64 opposite to the first end 62. The L-arm assembly 36 further includes a second arm

66 integral with and substantially transverse to the first arm 60. The second arm 66 has a first

end 68 integral with the first end 62 of the first arm 60 and a second end 70 opposite to the first

end 68 of the second arm 66. The second end 64 of the first arm 60 includes apertures 72 for

receiving a pivot member 74 for pivotal attachment to the power unit vehicle 32. The second end

70 of the second arm 66 includes an extended lift member 76 having an apertures 78 for

receiving a pivot member 80 for pivotal attachment to the supporting frame assembly 44 about

horizontal axis 46. The first arm 60 of the L-arm assembly 36 is longer than the second arm 66

of the L-arm assembly 36.

[0044] While it is anticipated that the L-arm assembly 36 could comprise one L-arm of

solid construction (not shown), the preferred embodiment as shown in Figs. 5 and 6 shows an

assembly of two separate L-arms 82 spaced apart by tubular support members 84. In addition,

Figs. 5 and 6 show that the first arm 60 of each L-arni 82 is comprised of a top plate 86 and first

and second side plates 88 and 90, respectively, the first side plate 88 being substantially parallel

with the second side plate 90 with a slight divergence between the first side plate 88 and second

side plate 90 from the first end 62 of the first arm 60 to the second end 64 of the first arm 60. In

addition, the second arm 66 of each L-arm 82 is comprised of a rectangular housing 94 with the

extended lift members 76 extended from the second end 70 thereof.

[0045] The L-arm assembly 36 also includes means for attachment to the hydraulic

cylinder 38 to raise and lower the L-arm assembly 36 in the form of two gusset plates 96 having

apertures 98 therein for receiving a pivot member 100 for pivotal attachment to the hydraulic cylinder 38. It is preferred that these means for attachment to the hydraulic cylinder 38 be

proximate to the first end 62 of the first arm 60 of the L-arm assembly 36.

[0046] In the preferred embodiment wherein the L-arm assembly 36 is made up of two

parallel L-arms 82, one of the parallel second arms 66 includes within its rectangular housing 94

means for extending and retracting the extended lift member 76. Means for extending and

retracting an extended lift member 102 relative to a rigidly connected extended lift member 104

are shown in Figs. 7 (extended) and 8 (retracted). A telescoping housing 106 is operably

attached between a linear actuator 108 (shown uncovered in Figs. 1-4) and the lift member 102.

[0047] While the L-arm assembly 36 of the present invention is shown on an excavating

machine 30 having a rock wheel trencher assembly 42, it is to be understood that this L-arm

assembly 36 could be incorporated with any type of excavating machine having earth cutting

means as original equipment or sold separately as a retrofit part for existing equipment.

[0048] Fig. 9 shows an enlarged elevational view of the supporting frame assembly 44

and the wheel assembly 50 mounted rotatably thereon. A hitch 116 having an aperture 118

therein is included for receiving pivot member 46 for pivotal attachment to the second end 70 of

the second arm 66 of the L-arm assembly 36. rn addition to pivotal movement upon extension or

retraction of the hydraulic cylinder 48, when the slidable lift member 102 is extended or retracted

relative to the fixed lift member 104 by linear actuator 108, the supporting frame assembly 44

and the wheel assembly 50 are adjustable from their normal vertical orientation. This is

beneficial when a vertical trench is to be dug on uneven ground or when a non- vertical trench is

to be dug.

[0049] The supporting frame assembly 44 also includes a flange 122 having an aperture

124 therein for receiving a fastening member 126 for operable attachment to the second hydraulic

cylinder 48 for the supporting frame assembly 44. Accordingly, as the second hydraulic cylinder

48 for the wheel frame assembly 44 is extended and retracted, the pitch of the supporting frame

assembly 44 is adjusted up or down in accordance therewith.

[0050] The wheel assembly 50 includes a digging wheel 128 having a rim structure 130

and a series of circumferentially spaced plate members 132 peripherally mounted to the rim

structure 130 of the digging wheel 128. A truck roller assembly 134 is rigidly connected to the

supporting frame assembly 44 for adjustment of the digging wheel 128 and to maintain the

digging wheel 128 in a desired position. The digging wheel 128 is driven in a counter-clockwise

direction as illustrated in Figs. 1-4, by a drive mechanism 136. As the digging wheel 128 rotates,

ripping teeth 138 of each plate member 132 strike a portion of trench leading edge 57, moving

upward against leading edge 57 freeing spoil 140 which is then carried within the plate members

132, arc plate 142, and the rim structure 130 to the top 141 of the digging wheel 128. The arc

plate 142 keeps the spoil from passing through the rim structure 130 until it reaches the top 141

of the digging wheel 128 where it then falls onto the conveyor assembly 52 for expelling laterally

to a spoil bank (not shown) on the side of the excavating machine 30.

[0051] Each plate member 132 comprises a generally flat plate having at least one ripping

tooth 138 mounted thereto, the at least one ripping tooth 138 extending outwardly from rim

structure 130.

[0052] Fig. 10 is a front elevation of rim structure 130 with plate member 132 mounted

thereto. Fig. 11 is a top perspective of an exemplary plate member 132 and Fig. 12 is a section

view taken along line 12-12 of Fig. 11. Exemplary plate member 132 is shown in Figs. 10-12 to

include a rectangular steel plate 133, preferably of steel, having a leading edge 137 which may

be, but need not be, tapered from longer outward face 135 to shorter inward face 139. Plate

member 132 is fixed to rim structure 130 which comprises spaced apart parallel rims 129 and

131. In the exemplary plate member 132 of Figs. 10-12, two ripping teeth 138 are fixed to

outward face 135 of plate member 132. Each ripping tooth 138 comprises a holder 170 and a

spike 172, with holder 170 receiving spike 172 and orienting it at angle a relative to outward face

135. Angle a is optimally between 32° and 62°, preferably approximately 47° to 52° in the

preferred embodiment. It is possible that other inclinations of ripping teeth 138 maybe useful

depending on the type of rocky condition encountered. Spikes 172 are preferably carbide tips

which are driven by wheel assembly 50 against the trench leading edge 57. Various geometries

of spikes 172 are contemplated such as chisels, knives, gouges, scoops and daggers. Variations

in the structures of the holders 170 and attachment of spikes 172 thereto may also be made while

adhering to the invention.

[0053] Each plate member 132 may further be provided with one or more spades 174

which maybe backhoe teeth which extend forward of leading edge 137 of plates 133. Spades

174 may comprise support legs 178, which lie along outward face 135 of plates 133, and shovels

176 which are disposed forward of leading edge 137 of plates 133. Shovels 176 preferably

incline away from outward face 135.

[0054] Figs. 13A and 13B illustrate a series of plate members 132 a-j carried on rim

structure 130. First plate member 132a of series of plate members 132a-j comprises a single

ripper tooth 138 located generally centrally on outward face 135 of series first plate member

132a. Also mounted to first plate member 132a are a pair of spades 174 spaced on either side of

single ripping tooth 138.

[0055] Spaced from first plate member 132a is second plate member 132b of series of plate

members 132a-j. Spacing between adjacent plate members may be about six inches while each

plate member 132 may be approximately six inches long though variations in both of these

dimensions may be selected, preferably within the range of three inches to fifteen inches, it

further to be understood that the length of the plate members 132 is not dependent on the spacing

between adjacent plate members 132, nor is the converse required. Second plate member 132b

comprises a pair of ripping teeth 138 spaced generally equidistantly from the center line 180 of

rim structure 130. Flanking ripping teeth 138 are pairs of spades 174 which may be mounted to

outward face 135 of second plate member 132b at positions generally equidistant from center line

180.

[0056] Spaced apart from second plate member 132b and mounted to rims 129 and 131 is

third plate member 132c of series of plate members 132a-j which comprises ripping teeth 138

and multiple spades 174. A centered spade 174 in the form of a backhoe tooth lies on center line

180 with the other spades 174 and the ripping teeth 138 spaced apart generally equidistantly from

center line 180.

[0057] Fourth plate member 132d of series of plate members 132a-j is spaced similarly

from third plate member 132c and from the next plate member 132e which will follow. Fourth

plate member 132d comprises a pair of spades 174 flanked by a pair of ripping teeth 138. It can

be observed that ripping teeth 138 on succeeding plate members 132b-j form a pattern with

ripping tooth 138 of first plate member 132a starting on the center line 180 and with ripping teeth 138 moving sequentially outward from the center line 180 with each succeeding plate member

132b-e. Spades 174 are disposed on each plate member 132 and are placed in locations spaced

apart from the ripping teeth 138. Generally ripping teeth 138 and spades 174 are symmetrically

disposed as to center line 180.

[0058] It is to be understood that the pattern of the ripping teeth 138 and spades 174 on

series of plate members 132a-j may repeat or the series of plate members 132a-j may comprise

additional plate members 132, each of which preferably includes at least one ripping tooth 138

and at least one spade 174. However, plate members 132 which have neither ripping teeth 138

nor spades 174 may be interspersed within or between series thereof. Furthermore, the use of

only one or more ripping teeth 138 on a plate member 132 without spades 174, or the use of only

one or more spades 174 without ripping teeth 138 on a selected plate members is also

contemplated.

[0059] Preferably, plate members 132 in series are constructed such that the first of a

series of plate members 132 has a single ripping tooth 138 centered thereon while the next plate

member 132 in the series includes two ripping teeth 138 each spaced approximately three inches

from the centerline 180 of the wheel assembly 50. The next plate member 132 in the series is

provided with two ripping teeth 138 each spaced approximately six inches from the centerline

180 and the subsequent plate member 132 includes two ripping teeth 138 each separated by

approximately nine inches from the centerline 180. Thereafter, the next following plate member

132 includes two ripping teeth each separated from the center line 180 by twelve inches. Then

the series may include a next following plate member 132 which includes two ripping teeth 138

straddling the centerline with each ripping tooth 138 at a distance of one and one-half inches

from the center line 180, followed by the next following plate member 132 provided with two

ripping teeth 138 each spaced approximately four and one-half inches from the centerline 180;

followed by a next plate member 132 including two ripping teeth 138 each spaced approximately

seven and one-half inches from the centerline 180; followed by a next plate member 132

including two ripping teeth 138 each spaced approximately ten and one-half inches from the

centerline 180. Thereafter the next following plate member 132 may be identical to the first plate

member 132a in the series having a centered single ripping tooth 138 and the series may then

repeat as needed to complete the periphery of the rim structure 130.

[0060] As seen in Figs. 13 A and 13B, the spades 174 are located on plate members 132

such that they are spaced laterally from the ripping teeth 138 and also symmetrically to the

centerline 180, including in some cases when three spades 174 may be utilized on a plate

member 132 with the middle of the spades 174 thereon centered on the centerline 180. In each

case, the spades 174 are directed toward the direction of movement of the plate members 132 as

the wheel assembly 50 is turned while the ripping teeth 138 are each angularly directed outward

from the plate members 132 with the spikes 172 thereof directed toward the direction of

rotational movement of the rim structure 130. Spades 174 extend forward of leading edges 137

of plate member 132 while spikes 172 are preferably located near the trailing edges 133 of plate

members 132.

[0061] The ripping tooth 138 of first plate member 132a shatters the trench leading edge

57 of the rocky ground 58 while the ripping teeth 138 of each succeeding plate member 132

strike a different area and may clear the spoil 140 created by the ripping tooth 138 of the

preceding plate members 132 or the ripping teeth 138 of the following plate members 132 may

shatter a different area of the trench leading edge 57.

[0062] The shovels 176 of each spade 174 do not extend outward from plate 133 as far as

the ripping teeth 138 do but do serve to scoop rock pieces and rocky soil in the trench, feeding

the spoil 140 toward the arc plate 142 and upward such that spoil 140 will pass to the top 141 of

wheel assembly 50 and be deflected by deflective face 150 (Fig. 14) onto the conveyor assembly

52. m addition, shovels 176 serve to excavate non-rocky soil which may be encountered, thereby

permitting the invention machine to be used on both rocky and non-rocky soils.

[0063] Deflecting member 144 is operably attached to the wheel frame assembly 44 at

146. The deflecting member 144 is shown in detail in Fig. 14 and is positioned within an interior

profile 148 defined by of the rim structure 130 and the plate members 132 of the digging wheel

128 in Fig. 15. The deflecting member 144 is positioned at an angle with a deflecting face 150

located at the top 141 of the digging wheel 128 in such a manner that it removes the spoil 140

which has accumulated in the rim structure 130 between the plate members 132 of the digging

wheel 128 and the arc plate 142. Deflecting member 144 directs the spoil 140 downwardly onto

the conveyor assembly 52. The deflecting face 150 corresponds substantially in size and shape to

the interior profile 148 of the rim structure 130 and the plate members 132, the deflecting face

150 thereby fitting within the interior profile 148 formed by the rim structure 130 and the plate

members 132 to remove substantially all of the spoil 140 which has accumulated within interior

profile 148.

[0064] The deflecting face 150 may be arcuate in lateral cross-section (Fig. 14) and in

longitudinal cross-section resulting in a concave shape in order to deflect the spoil 140

downward.

[0065] In the preferred embodiment, the deflecting face 150 is rigidly attached to a

support member 152 which is carried on the frame assembly 144. Compression coil springs (not

shown) within housing 154 may longitudinally bias the deflecting face 150 into position within

the interior profile 148 of the rim structure 130 and the plate member 132 as well as permit the

deflecting face 150 to retract upon contact with an obstruction (not shown) within the interior

profile 148 of the rim structure 130 and the plate member 132. This configuration allows for

positive cleaning while preventing damage upon contact with an obstruction.

[0066] An alternative embodiment of the cleaning member 144 is shown in FIG. 16. In this

embodiment, a cleaning face 170 is attached directly to a mounting arm 172 which is pivotally

mounted to a wheel frame assembly 174 about a horizontal axis 176. A coiled spring 178 is

rigidly connected between the mounting arm 172 at 180 and the wheel frame assembly 174 at

182 to provide alternative biasing and retraction means. However, the cleaning face 184 and the

ultimate position of the cleaning face 184 within the interior profile 148 of the rim structure 130

and the bucket member 132 would be identical.

[0067] In the preferred embodiment, it is found that the wheel speed may be accelerated

over that which is known in the art and that the cutting effect of the earth cutting assembly 40

may be improved by rotation of the wheel assembly 50 at a sufficient speed that the speed of

travel of any of ripping teeth 138 across the leading trench edge 57 is not less than approximately

fifteen feet per second, and preferably approximately at least eighteen feet per second. The

inclusion of the deflecting member 144 and the conveyor assembly 52 in coordination with the

novel plate members 132 mounted on the rim structure 130 enables the rapid rotation of the

wheel assembly 52 such that the ripping teeth 138 pass the leading trench face 57 at an angular

velocity of in excess of fifteen feet per second. In some ground conditions however, it may be

necessary to operate the wheel assembly 50 at a slower speed at which the excavating machine

will remain fully functional.

[0068] The conveyor assembly of the present invention is shown in Figs. 17-20. The

conveyor assembly 52 is operably attached to the wheel frame assembly 44 in a suspended

manner at 186 and 188. This allows the conveyor assembly to be tilted from one side to another

depending upon from which side the spoil 140 is to be expelled. The conveyor assembly 52

comprises an interior portion 190 bounded by a first end roller 192 and a second end roller 194

opposite to the first end roller 192, an endless conveyor belt 196 about the first end roller 192 and

the second end roller 194, a first side assembly 198 and a second side assembly 200 opposite to

the first side assembly 198, all to prevent the spoil 140 from entering the interior portion 190 of

the conveyor assembly 52.

[0069] The conveyor assembly 52 further comprises a top plate 202 on which the endless

conveyor belt 196 slides, hi the preferred embodiment, this top plate 202 is made of an ultra¬

high molecular weight plastic to provide a minimal amount of friction between the endless

conveyor belt 196 and the top plate 202. However, it is anticipated that other materials could be

used. While the top plate 202 is shown in the preferred embodiment as separate plates 204 and

206 which are located side-by-side with a longitudinal channel 208 therebetween, it is to be

understood that a single top plate could also be used having a longitudinal groove therein (not

shown). The top plates 204 and 206 of the conveyor assembly 52 extend laterally beyond the

first side assembly 198 and the second side assembly 200, respectively, in a manner so as to

overlap the side assemblies 198 and 200 to prevent spoil 140 from entering the interior portion

190 of the conveyor assembly 52.

[0070] In the preferred embodiment, the endless conveyor belt 196 includes a series of

finger-like projections 210 (Figs. 19 and 20) along its underside 212 corresponding in alignment

with the longitudinal channel 208 between the first top plate 204 and the second top plate 206 of

the conveyor assembly 52 in order to act in combination as a guide for centering the endless

conveyor belt 196 on the conveyor assembly 52. hi addition, the first end roller 192 and the

second end roller 194 each include an annular groove 214 and 216, respectively, in alignment

with the longitudinal channel 208 between the first top plate 204 and the second top plate 206 of

the conveyor assembly 52 in order to receive the finger-like projections 210 on the underside 212

of the endless conveyor belt 196 again to center the endless conveyor belt 196 on the conveyor

assembly 52. The centering of the endless conveyor belt 196 on the conveyor assembly 52 is also

assisted by a tapering of the first end roller 192 and the second end roller 194 wherein the center

portion 218 and 220 of the first end roller and second end roller, respectively, is larger in

diameter than the end portions 222 and 224 and 226 and 228 of the first end roller 192 and the

second end roller 194, respectively.

[0071] A belt tension adjuster 230 allows an end member 232 of the first side assembly

198 and an end member 234 of the second side assembly 200, respectively, to be extended or

retracted as necessary The tension adjuster 230 comprises a thumb screw 231 which, upon

turning along threaded rod 236, either extends or retracts the end members 232 and 234 of the

first side assembly 198 and the second side assembly 200, respectively, along with the second

end roller 194. The first end roller 192 is rigidly connected along with end members 238 and 240

of the first side assembly 198 and the second side assembly 200, respectively.

[0072] The first side assembly 198 and the second side assembly 200 further includes

downwardly extended flanges 242 and 244, respectively, for preventing the spoil 140 from

entering the interior portion 190 on the underside 246 of the conveyor assembly 52. For the

minimal amount of spoil 140 that does enter the interior portion 190 of the conveyor assembly

52, a plow assembly is operably attached therein to direct the spoil 140 back out from the interior

portion 190 of the conveyor assembly 52. The shoe assembly 54 is a diamond-shaped

configuration of stop plates 250, 252, 254 and 256 which are angled towards the first side

assembly 198 and the second side assembly 200. Accordingly, as spoil riding on the underside

212 of the endless conveyor belt 196 comes into contact with the stop plates 250-256 it is

directed out of the conveyor assembly 52.

[0073] Once again, while the conveyor assembly 52 of the present invention is shown on

an excavating machine 30 having a rock wheel trencher assembly 42, the conveyor assembly 52

could be incorporated with any type of excavating machine having earth cutting means either as

original equipment or sold separately as a retrofit part for existing equipment.

[0074] The shoe assembly 54 of the present invention is shown in Figs. 21-26. The shoe

assembly 54 includes a post member 258 for operable attachment at 260 with the supporting

frame assembly 44. The shoe assembly further includes side plates 262 and 264 for contact with

the side walls of the trench 56 in order to prevent a cave-in of the side walls of the trench 56

during use. The side plates 262 and 264 are supported and maintained in a spaced relationship

by a tubular support assembly 266 which extends downwardly from the post member 258.

[0075] Grooving means 268 are operably attached along the bottom edge 270 of the shoe

assembly 54 and extend therebelow to form a groove 272 in the bottom 274 of the trench 56. In

the preferred embodiment, the grooving means 268 comprise adjustable groove means 276 for

adjusting the radial dimension of the groove 272. The adjustable groove means 276 includes a

mounting assembly 278 including a mounting plate 280 rigidly connected to a bottom member

282 of the shoe assembly 54. The mounting assembly 278 of the adjustable groove means 276

also includes side mounting plates 284 and 286 rigidly connected to sidewalls 262 and 264,

respectively, of the shoe assembly 54 and a rear mounting plate 288 operably attached between

the side mounting plates 284 and 286.

[0076] Suspended within the mounting assembly 278 and pivotally connected about a

pivot member 290 extended rearwardly from the front mounting plate 280 is the adjustable

groover assembly 291 of the adjustable groove means 276. The adjustable groover assembly 291

comprises a first arcuate groove plate 292 and a second arcuate groove plate 294 having apertures

296 and 298, respectively, for receiving the pivot member 290 extended rearwardly from the

front mounting plate 280, the first arcuate groove plate 292 and the second arcuate groove plate

294 in combination resulting in an arc 300 of varying radius for forming the groove 272 in the

bottom 274 of the trench 56.

[0077] Means for pivoting the first arcuate groove plate 292 relative to the second arcuate

groove plate 294 are included comprising a linear actuator 302 having a first end 304 and a

second end 306 opposite to the first end 304.

[0078] The first end 304 of the linear actuator 32 is operably attached to a hand-crank

assembly 308 which is operably attached at the top edge 310 of the shoe assembly 54. The

second end 306 of the linear actuator 302 is operably attached to a yoke member 312 having an

aperture 314 for receiving a pivot member 316 therein. First and second link members 318 and

320 each having a first end 322 and 324, respectively, and a second end 326 and 328,

respectively, are pivotally attached at their first ends 322, 324 to the yoke member 312 and at

their second ends 324, 326 to the first arcuate groove plate 292 and the second arcuate groove

plate 294, respectively, at pivot points 328 and 330, respectively.

[0079] Accordingly, as the linear actuator 302 is extended, the link members 318 and 320

extend the first arcuate groove plate 292 and the second arcuate groove plate 294 apart to form a

groove of a larger radius. Likewise, when the linear actuator 302 is retracted, the link members

318 and 320 retract the first arcuate groove plate 292 relative to the second arcuate groove plate

294 to create a groove of a smaller radius.

[0080] A nose cone member 332 extends in front of the front mounting plate 280 in the

direction of travel of the excavating machine 30 to penetrate the ground 58 to make way for the

adjustable groover assembly 291.

[0081] And again, while the adjustable groover assembly 276 of the present invention is

shown on an excavating machine 30 having a rock wheel trencher assembly 42, it is to be

understood that the adjustable groover assembly 276 could be incorporated with any type of

excavating machine having earth cutting means as original equipment or sold separately as a

retrofit part for existing equipment.

[0082] The foregoing description and drawings merely explain and illustrate the

invention, and the invention is not limited thereto, except insofar as the claims are so limited as

those skilled in the art who have the disclosure before them will be able to make modifications

and variations therein without departing from the scope of the invention.