Trenchers having a shroud assembly

Abstract

A trencher for cutting a trench into a trenching surface. The trencher includes a rotatable cutting wheel and a motor for rotating the cutting wheel. The trencher includes a shroud assembly. The rotatable cutting wheel is at least partially disposed within the shroud assembly. A lift frame raises and lowers the cutting wheel and shroud assembly. A lift frame actuator moves the lift frame from a transport position to a lowered, trenching position. A skid is connected to the lift frame for contacting the trenching surface during trenching operations. The skid is forward of the shroud assembly. The shroud assembly is moveable relative to the skid. A downforce device enables the skid to apply a downforce to the trenching surface during trenching operations. The downforce device is separate from the lift frame actuator.

Description

TRENCHERS HAVING A SHROUD ASSEMBLYCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 640, 319, filed April 30, 2024, which is incorporated herein by referenced in its entirety.FIELD OF THE DISCLOSURE

[0002] The field of disclosure relates generally to trenchers and, in particular, trenchers having a shroud assembly for shrouding the cutting blade during trenching operations.BACKGROUND OF THE DISCLOSURE

[0003] Trenchers are used for installation of underground utilities. "Microtrenchers" are a class of trenchers that include a cutting wheel which cuts a trench into a trenching surface such as concrete or asphalt. While the cutting wheel rotates and forms the trench, the spoil material is removed from the trenching site through a vacuum system. After the trench is formed and the utility is installed, the trench may be filled with filler material.

[0004] During trenching operations, the cutting blade may become unstable due to the forces exerted on the cutting blade during cutting. Further, it is difficult to guard the cutting blade during some trenching operations such as when the cutting blade is plunged into the trenching surface to the desired trenching depth.

[0005] A need exists for a trencher that is stable during trenching operations and that guards the cutting wheel during trenching including while the cutting wheel is plunged into the trenching surface.

[0006] This background section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present disclosure, which are described and / or claimed below. This discussion is believed to be helpful in providing the reader with supporting information to facilitate a better understanding of the various aspects of the present disclosure. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.SUMMARY OF THE DISCLOSURE

[0007] The exemplary embodiments disclosed herein describe a microtrencher for installing a utility.

[0008] One aspect of the present disclosure is directed to a trencher for cutting a trench into a trenching surface. The trencher includes a rotatable cutting wheel, a motor for rotating the cutting wheel, and a shroud assembly. The rotatable cutting wheel is at least partially disposed within the shroud assembly. The trencher includes a lift frame for raising and lowering the cutting wheel and shroud assembly and includes a lift frame actuator for moving the lift frame from a transport position to a lowered, trenching position. The trencher includes a skid connected to the lift frame for contacting the trenching surface during trenching operations. The skid is forward of the shroud assembly. The shroud assembly is moveable relative to the skid. A downforce device enables the skid to apply a downforce to the trenching surface duringtrenching operations. The downforce device is separate from the lift frame actuator.

[0009] Another aspect of the present disclosure is directed to a trencher for cutting a trench into a trenching surface. The trencher includes a rotatable cutting wheel, a motor for rotating the cutting wheel, and a shroud assembly. The rotatable cutting wheel is at least partially disposed within the shroud assembly. The trencher includes a mounting frame for connecting the trencher to a base vehicle and a lift frame that pivotally connects the shroud assembly to the mounting frame for moving the cutting wheel and shroud assembly from a raised position to a lowered position. A pull arm assembly is connected to the lift frame, the mounting frame, or both the lift frame and the mounting frame. A lift frame actuator is pivotally connected to the pull arm assembly to raise the shroud assembly when actuated in a first direction and causes the pull arm assembly to apply a force to a downforce device connected to the lift frame and the pull arm assembly.

[0010] Yet another aspect of the present disclosure is directed to a trencher for cutting a trench into a trenching surface. The trencher includes a rotatable cutting wheel, a motor for rotating the cutting wheel, and a shroud assembly. The rotatable cutting wheel is at least partially disposed within the shroud assembly. The trencher includes a skid for contacting the trenching surface during trenching operations. The skid is forward of the shroud assembly. The skid is separate from the shroud assembly. The trencher includes a downforce device that enables the skid to apply a downforce to the trenching surface during trenching operations.

[0011] As used herein, "a," "an," and "the" refer to both singular and plural referents unless the context clearly dictates otherwise.

[0012] As used herein, the term "about" refers to a measurable value such as a parameter, an amount, a temporal duration, and the like and is meant to include variations of + / - 15% or less, preferably variations of + / - 10% or less, more preferably variations of + / - 5% or less, even more preferably variations of + / - 1% or less, and still more preferably variations of + / - 0.1% or less of and from the particularly recited value, in so far as such variations are appropriate to perform in the one or more embodiments of the disclosure described herein. Furthermore, it is also to be understood that the value to which the modifier "about" refers is itself specifically disclosed herein.

[0013] As used herein, spatially relative terms, such as "beneath," "below," "lower," "above," "upper," "front," "back," "side," "left," "right," "rear," "top," "bottom," and the like, are used for ease of description to describe one element or feature's relationship to another element(s) or feature(s). It is further understood that the terms "front," "back," "left," and "right" are not intended to be limiting and are intended to be interchangeable, where appropriate. Further, it should be noted that the terms "first," "second," and the like herein do not denote any order, quantity, or relative importance, but rather are used to distinguish one element from another.

[0014] As used herein, the terms "comprise(s)," "comprising," and the like, specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0015] As used herein, the terms "configure(s)" "configuring," and the like, refer to the capability of a component and / or assembly, but do not preclude the presence or addition of other capabilities, features, components, elements, operations, and any combinations thereof.

[0016] All ranges disclosed herein are inclusive of the endpoints, and the endpoints are independently combinable with each other. Each range disclosed herein constitutes a disclosure of any point or sub-range lying within the disclosed range.

[0017] All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., "such as"), is intended merely to better illustrate the present disclosure and does not pose a limitation on the scope of the present disclosure or any embodiments unless otherwise claimed.

[0018] Any combination or permutation of features, functions, and / or embodiments as disclosed herein is envisioned. Additional advantageous features, functions, and applications of the disclosed systems, methods, and assemblies of the present disclosure will be apparent from the description which follows, particularly when read in conjunction with the appended figures. All references listed in this disclosure are hereby incorporated by reference in their entireties.BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Features and aspects of embodiments are described below with reference to the accompanying drawings, in which elements are notnecessarily depicted to scale. Corresponding reference characters indicate corresponding parts throughout the several views of the drawings.

[0020] Exemplary embodiments of the present disclosure are further described with reference to the appended figures. It is to be noted that the various features, steps and combinations of features / steps described below and illustrated in the figures can be arranged and organized differently to result in embodiments which are still within the scope of the present disclosure.

[0021] To assist those of ordinary skill in the art in making and using the disclosed assemblies and systems, reference is made to the appended figures, wherein:

[0022] FIG. l is a side view of a trencher of the present disclosure;

[0023] FIG. 2 is a perspective view of the trencher;

[0024] FIG. 3 is a top view of the trencher;

[0025] FIG. 4 is a detailed perspective view of a mounting frame and lift frame of the trencher;

[0026] FIG. 5 is a detailed perspective view of the lift frame of the trencher;

[0027] FIG. 6 is a detailed perspective view of a four-bar linkage of the lift frame;

[0028] FIG. 7 is a side view of the lift frame in a lowered position with the lower pull arm contacting an up-stop;

[0029] FIG. 8 is a side view of the lift frame in a raised position with the upper pull arm contacting a down-stop;

[0030] FIG. 9 is a side view of the lift frame in a float position;

[0031] FIG. 10 is a perspective view of a linkage of the lift frame connected to the skid;

[0032] FIG. 11 is a perspective view of a motor and cutting wheel of the trencher;

[0033] FIG. 12 is a front view of the shroud assembly and a linkage of the lift frame;

[0034] FIG. 13 is a perspective view of the trencher with the outer shroud and cutting wheel in a lowered position;

[0035] FIG. 14 is a side view of the shroud assembly with the outer shroud in a raised position;

[0036] FIG. 15 is a perspective view of the shroud assembly with the outer shroud in a lowered position;

[0037] FIG. 16 is a perspective view of the shroud assembly and vacuum system of the trencher;

[0038] FIG. 17 is another perspective view of the shroud assembly;

[0039] FIG. 18 is a side view of the cutting wheel, shroud assembly and vacuum coupling with the cutting wheel in a trenching position;

[0040] FIG. 19 is a side view of the trencher with the cutting wheel plunged into the trenching surface;

[0041] FIG. 20 is a detailed side view of the trencher showing the cutting wheel and skid;

[0042] FIG. 21 is a schematic view of the perimeter formed around the cutting wheel by the shroud assembly at the trenching surface;

[0043] FIG. 22 is a side view of the trencher and a base vehicle, with the trencher in a transport position;

[0044] FIG. 23 is a side view of the trencher and the base vehicle with the trencher in a lowered, trenching position before plunging the cutting blade into the trenching surface;

[0045] FIG. 24 is a side view of the trencher and the base vehicle with the trencher in a lowered position during trenching operations;

[0046] FIG. 25 is a side view of another embodiment of the trencher having an actuator for pivoting the lift frame about a vertical pivot axis; and

[0047] FIG. 26 is a detailed side view of the trencher of FIG. 25 having an up-stop that prevents the inner shroud from pivoting upward with the outer shroud.DETAILED DESCRIPTION OF THE DISCLOSURE

[0048] Referring now to FIGS. 1-2, a microtrencher 10 or more simply "trencher" for cutting a trench into a trenching surface is shown. Trencher 10 includes a rotatable cutting wheel 12 and a motor 16 for rotating the cuttingwheel 12. The trencher 10 includes a mounting frame 20 for connecting the trencher 10 to a base vehicle V (FIG. 22). Example base vehicles include a utility tractor, trailer, truck, and a tool carrier (e.g., mounted to the loader arms of the tool carrier).

[0049] Microtrenchers generally have a cutting width ranging from 0.75 inches to 3 inches. However, the present disclosure should not be limited to a particular trenching width unless stated differently. Further, features of the trencher described and shown herein may also be incorporated within rockwheels, vibratory plows and trenchers having different components and / or arrangement of components.

[0050] The trencher 10 includes a shroud assembly 24 that shrouds the cutting wheel 12 during trenching operations. The trencher 10 includes a lift frame 28 for raising and lowering the cutting wheel 12 and the shroud assembly 24. The lift frame 28 is pivotally connected to the mounting frame 20 and pivots about a vertical pivot axis Y (FIG. 1) defined by a pivot pin 32. In the illustrated embodiment, the lift frame 28 and shroud assembly 24 pivot about the vertical axis Y by rotating the position of adjustment nuts 36 (FIG. 4) on an adjustment pin 38. The adjustment pin 38 extends between a mount plate 40 of the mounting frame 20 and a leg 44 of the lift frame 28.

[0051] The lift frame 28 and shroud assembly 24 may be caused to pivot about the vertical axis Y in other arrangements. For example, in the embodiment of the trencher 1010 shown in FIG. 25, an actuator 1090 (e.g., hydraulic cylinder) pivots the lift frame 1028 (and shroud assembly and cutting wheel) about the pivot axis Y. Pivoting the lift frame 1028 enables the cutting wheel to be positioned correctly to start a cut or when reinserting the blade tocontinue an existing cut. Once the cutting wheel 12 is correctly positioned, the actuator 1090 may be operated in a "float" mode in which the actuator 1090 freely extends or retracts during cutting.

[0052] As shown in FIG. 3, the vertical pivot axis Y is generally aligned with the cutting wheel 12 (which is within the shroud assembly 24) along the cutting axis X12 such that the force to pull the trencher 10 forward during a trenching operation is vertically aligned with the cutting axis X12. The vertical alignment of the pulling force with the vertical pivot axis Y reduces or prevents a bending moment on the cutting wheel 12 and / or mounting frame 20 due to forces generated during trenching operations.

[0053] The mounting frame 20 incudes a slide assembly 48 (FIG. 4) to adjust the lateral position of the cutting wheel 12. The slide assembly 48 includes a slide actuator 52 attached to the mount plate 40. Extension and retraction of the slide actuator 52 causes the mount plate 40 (and cutting wheel 12) to move laterally. The mounting frame 20 includes base vehicle connection plates 54, 58 (FIG. 6) for connecting the trencher 10 to the base vehicle.

[0054] Referring now to FIG. 5, the lift frame 28 includes a four-bar linkage 56. The four-bar linkage 56 includes a frame member 60 that is pivotally connected to the mount plate 40. The frame member 60 is pivotally connected to an upper linkage 64 and is pivotally connected to a lower linkage 68. The four-bar linkage 56 also includes a vertical linkage 72. The vertical linkage 72 is pivotally connected to the upper linkage 64 and is pivotally connected to the lower linkage 68. A lift frame actuator 80 is pivotally connected to the frame member 60 at a first end 82 of the lift frame actuator 80 at a lower pivot pin 86 and is pivotally connected to a pull arm assembly 94 at an upper pivot pin 90.

[0055] The pull arm assembly 94 is pivotally connected to the lift frame 28 (i.e., frame member 60) by pivot pin 98 which defines a pivot axis X94 about which the pull arm assembly 94 rotates. The pull arm assembly 94 is generally v-shaped and includes an upper pull arm 102 and a lower pull arm 104 that are angled with respect to each other. The pull arm assembly 94 has a width greater than the width of the upper linkage 64 such that the upper linkage 64 is at least partially disposed within the pull arm assembly 94. In other embodiments, the pull arm assembly 94 is pivotally connected to the mounting frame 20 or connected to both the lift frame 28 and the mounting frame 20.

[0056] The upper pull arm 102 of the pull arm assembly 94 is pivotally connected to a downforce device 100 at a first end 106 of the downforce device 100. The downforce device 100 is pivotally connected to the upper linkage 64 (FIG. 6, with the pull arm assembly not shown for illustration) at a second end 112 of the downforce device 100. In the illustrated embodiment, the downforce device 100 is a spring element (i.e., a spring having a rod moveable within a barrel (i.e., damper or shock absorber) with the spring applying a downward spring force upon retraction of the rod into the barrel). In other embodiments, the downforce device 100 is an actuator (e.g., pneumatic element or hydraulic element) or is a shock absorber (i.e., without having a spring element) or a combination of spring, pneumatic, or hydraulic elements. The downforce device 100 is separate device from the lift frame actuator 80.

[0057] As discussed further below, the lift frame actuator 80 raises the should assembly 24 and cutting wheel 12 when the actuator 80 is actuated in a first direction (i.e., extended). The lift frame actuator 80 causes the pull arm assembly 94 to apply a force to the downforce device 100 when actuated in a second direction (i.e., retracted).

[0058] The lift frame actuator 80 moves the lift frame 28 from a trenching position (FIG. 23) to a travel position (FIG. 24). Extension and retraction of the lift frame actuator 80 causes the pull arm assembly 94 to pivot about the pivot axis X94. The pull arm assembly 94 moves along a path of travel that is limited by a down-stop 116 (FIG. 5) and an up-stop 120. The stops 116, 120 may be made of any suitable material such as rubber. When the actuator 80 is extended (FIG. 22), the pull arm assembly 94 pivots upward until the lower pull arm 104 contacts the up-stop 120 (FIG. 7, with a side of the pull arm assembly 94 not shown for illustration). Once the lower pull arm 104 contacts the up-stop 120, further extension of the actuator 80 causes the trencher 10 (i.e., shroud assembly 24 and cutting wheel 12) to lift.

[0059] The travel of the pull arm assembly 94 is also limited by the down-stop 116. When the actuator 80 is retracted (FIG. 8, with a side of the pull arm assembly 94 not shown for illustration), the upper pull arm 102 of the pull arm assembly 94 contacts the down-stop 116. In between the positions of the pull arm assembly 94 of FIG. 7 and FIG. 8, the lift frame 28 may be in a "float" position (FIG. 9, with a side of the pull arm assembly 94 not shown for illustration) in which the pull arm assembly 94 does not contact either the down-stop 116 or the up-stop 120. In the float position, the downforce device 100 is compressed which causes the downforce device 100 to apply a downforce to the upper linkage 64 and, in turn, to the vertical linkage 72 and a skid 124 that is discussed further below.

[0060] As shown in FIGS. 1 and 5, the skid 124 is forward of the shroud assembly 24 (and in the illustrated embodiment is separate from the shroud assembly 24). The skid 124 contacts the trenching surface that is disposed forward of the surface being trenched during trenching operations. As shownin FIG. 10, the skid 124 is connected to the lift frame 28 and, in the illustrated embodiment, is attached to the vertical linkage 72 (e.g., is integral with the vertical linkage 72). The vertical linkage 72 has a connecting plate 128 that connects the skid 124 to the vertical linkage 72. The shroud assembly 24 is moveable relative to the skid 124.

[0061] The shroud assembly 24 forms a perimeter P (FIG. 21) around the cutting blade 12 at or nearthe trenching surface. The perimeter P is defined by the bottom edges 126, 130 (FIG. 17) of first and second sides 134, 138 of the inner shroud 132. The perimeter P is also defined by a bottom edge 160 of an arcuate plate 164 that extends between the first and second sides 134, 138. The perimeter P is also defined by a bottom edge 192 (FIG. 20) of a rear plate 196. The perimeter P prevents spoil material from being expelled below the inner shroud 132 and helps maintain removal of spoil material through a vacuum system 170 (FIG. 16). As shown in FIG> 21, the skid 124 is forward of the perimeter P formed by the shroud assembly 24.

[0062] As shown in FIGS. 1-2, the rotatable cutting wheel 12 is at least partially disposed within the shroud assembly 24. The shroud assembly 24 includes an inner shroud 132 and an outer shroud 136. The cutting wheel 12 is at least partially received in the inner shroud 132 (in lowered and raised positions of the cutting wheel 12). The motor 16 and cutting wheel 12 are connected to the outer shroud 136. A shaft 18 (FIG. 11) of the motor 16 extends through an arcuate slot 140 (FIG. 1) formed in the inner shroud 132. The motor 16 is mounted to the outer shroud 136 by fasteners 42 (FIG. 5). A protective plate 76 (FIG. 2) is disposed below the motor 16 to protect the motor 16 from impact by the terrain and / or by cutting debris.

[0063] The outer shroud 136 is moveable with respect to the inner shroud 132. The trencher 10 includes a shroud actuator 144 (FIG. 13) that moves the outer shroud 136. The shroud actuator 144 is connected to the outer shroud 136 at a first end 146 (FIG. 13) of the actuator 144 and is connected to the vertical linkage 72 at a second end 152 of the actuator 144. Upon extension of the actuator 144 (FIG. 13), the outer shroud 136 is lowered onto and continually envelops the inner shroud 132.

[0064] The inner shroud 132 and outer shroud 136 both pivot about pivot pin 148 (FIG. 2) which defines a pivot axis X24. The inner shroud 132 remains in a lowered position contacting the trenching surface (due to the weight of the inner shroud 132) and may pivot upward or downward with changes in the terrain. The outer shroud 136 pivots upon operation of shroud actuator 144. The pivot point 148 also extends through the vertical linkage 72 which pivots about the pivot pin 148 about operation of the lift frame actuator 80.

[0065] The inner shroud 132 and outer shroud 136 are each spaced from the trenching surface a distance adjacent the pivot pin 148. Downforce applied by the downforce device 100 translates to the skid 124 and not the inner shroud 132 or outer shroud 136.

[0066] The outer shroud 136 may cover at least 25% or 50% or more of the surface area of the cutting wheel 12 when viewed from the side (FIG. 1). When the cutting wheel 12 is in the raised position (FIG. 1), the inner shroud 132 covers beyond the periphery of the cutting wheel 12. When cutting, the ground-contacting bottom surface 150 of the inner shroud 132 forms a perimeter around the cutting wheel 12. As the cutting wheel 12 is lowered andplunges into the trenching surface, the inner shroud 132 covers the periphery of the cutting wheel 12 that extends below the outer shroud 136 and above the trenching surface. When the cutting wheel 12 is in a raised position, the inner shroud 132 covers beyond the periphery of the cutting wheel 12 that extends below the outer shroud 136.

[0067] Referring now to FIG. 14 in which a side of the outer shroud 136 is not shown for illustration, the trencher 10 includes an inner shroud down-stop 154 which prevents the inner shroud 132 from pivoting downward beyond the outer shroud 136 such that a portion of the inner shroud 132 overlaps a portion of the outer shroud 136 when viewed from the side (FIG. 1) continually during trenching to prevent a gap from forming between the upper edge 142 (FIG. 14) of the inner shroud 132 and the lower edge 156 of the outer shroud 136. The downward pivoting movement of the inner shroud 132 (by gravity) allows the shroud assembly 24 to extend beyond the periphery of the cutting wheel 12 for the portion of the cutting wheel 12 that is above the trenching surface T. A first set of projections 158 of the inner shroud 132 contacts the down-stop 154 upon downward pivoting of the inner shroud 132. The trencher 10 includes an inner shroud up-stop 162 (FIG. 15, with a side of the outer shroud 136 not being shown for illustration) that limits upward rotation of the inner shroud 132. A second set of projections 166 of the inner shroud 132 contact the up-stop 162 upon full upward pivoting of the inner shroud 132. The extension length of the shroud actuator 144 is set (i.e., limited) to prevent the outer shroud 136 from pivoting to the extent that the outer shroud 136 contacts the inner shroud 132 and causes the inner shroud 132 to apply a downforce to the trenching surface T (i.e., a downforce greater than the weight of the shroud assembly 24).

[0068] In the embodiment of FIG. 26, the trencher 1010 includes an inner shroud up-stop 1118 that prevents the inner shroud 1132 from pivoting upward with the outer shroud 1136 such as when an object (e.g., a rock or portion of trenched material) becomes lodged between the outer shroud 1136 and the inner shroud 1132 during cutting.

[0069] The trencher 10 may include a vacuum system 170 (FIG. 16) for removing spoil material during trenching operations. The vacuum system 170 may include a vacuum coupling 174 that extends into the shroud assembly 24 and is replaceably removable from the shroud assembly 24. The vacuum coupling 174 is connected to the outer shroud 136 which allows the coupling to move with the cutting wheel 12 and remain in close proximity to the cutting wheel 12 when the outer shroud 136 pivots downward such that a portion of the cutting wheel 12 is below the trenching surface T during trenching operations. This arrangement enables the central axis A of the vacuum inlet 184 (FIG. 19, with a side of the shroud assembly not shown for illustration) and the projection of spoils from the trench to be tangential to the cutting wheel 12 (and to the forwardmost edge FE of the trench) during rotation of the cutting wheel 12 (in direction R) regardless of the cutting depth D. The vacuum system 170 may include spoils separation device(s) 176 (FIG. 16) and a vacuum pump 178 for removal of spoils during trenching and as the trencher 10 moves forward (indicated by arrow F). The vacuum coupling 174 may include a pipe pressure fitting 194 (FIG. 18) that compresses against the vacuum inlet 184 when tightened. The vacuum coupling 174 (including inlet 184) may be interchanged with a new vacuum coupling 174 by loosening the pipe pressure fitting 194. The coupling 174 is then removed from the shroud assembly 24 and interchanged with a new coupling 174. The pipe pressure fitting 194 alsoY1 enables the depth of the inlet 184 within the shroud assembly 24 to be adjusted.

[0070] The outer shroud 136 may include an outer shroud access panel 186 (FIG. 17) that swings open via outer shroud hinges 180 to provide access to the cutting wheel 12. The inner shroud 132 may similarly include an inner shroud access panel 188 that swings open by hinges 182 to access the cutting wheel 12.

[0071] To conduct a trenching operation, the mounting frame 20 of the trencher 10 is mounted to a base vehicle V as shown in FIG. 22. The lift frame actuator 80 is extended such that the lower pull arm 104 of the pull arm assembly 94 contacts the up-stop 120 (FIG. 7). The actuator 80 is further extended such that the actuator 80 causes the trencher 10 to be lifted from the ground (FIG. 22). Once raised, the base vehicle V moves to position the trencher 10 at the starting position for the trench. The lift frame actuator 80 is retracted to lower the trencher 10 until the skid 124 contact the trenching surface T. The actuator 80 is further retracted until the pull arm assembly 94 is in its "float position" (FIG. 23) in which the downforce device 100 is compressed to cause the skid 124 to apply a downforce on the trenching surface that is forward of the shroud assembly 24.

[0072] Once a downforce is applied through the skid 124, the cutting wheel 12 is caused to rotate and the shroud actuator 144 is extended to plunge the cutting wheel 12 into the trenching surface to the desired trenching depth. During plunging, the outer shroud 136 is lowered from its raised position (FIG. 23) to increasingly envelop the inner shroud 132 and reach a lowered position (FIG. 24) in which the inner shroud 132 is at least partially received in the outershroud 136. Once the desired trench depth is achieved, the base vehicle V is moved forward (shown by arrow F) to cut the trench into the trenching surface T.

[0073] Various adjustments may be made during the trenching operation including, for example, adjustment of downforce applied to the trenching surface T through skid 124, adjusting the trenching depth, operating the vacuum system 170 for spoils removal, changing the speed of the cutting wheel 12, starting and stopping the cutting wheel 12, and changing the travel speed of the base vehicle V.

[0074] Compared to conventional trenchers, the trencher of the present disclosure have several advantages. By use of a skid that applies downforce to the trenching surface forward of the shroud assembly, the cutting wheel remains stable during trenching operations (i.e., side-to-side "wobble" of the cutting wheel is reduced). The downforce device allows a consistent downforce to be applied through the skid even when protrusions and dips in the trenching surface are encountered. Use of a shroud assembly having an inner shroud and an outer shroud that is lowered to envelop the inner shroud allows the cutting blade to be shrouded during all trenching operations including plunging of the cutting wheel. When the trencher encounters protrusions and dips in the trenching surface, the pull-arm assembly may move upward or downward which provides more consistent operation. Up-stops and down-stops for the inner shroud allow the cutting wheel to be continually shrouded during trenching operation. By aligning the cutting wheel with the vertical pivot axis, turning forces generated during trenching operations may be reduced. Use of a pipe pressure fitting in the vacuum coupling allows for the coupling to be switched out and for the depth of the inlet to be adjusted. Beextending the motor shaft rather than the motor housing through the slot in the inner shroud, the size of the slot may be reduced which increases vacuum efficiency.

[0075] The following clauses further define particular aspects and embodiments of the present disclosure.

[0076] While the disclosure has been described with reference to preferred embodiments, it will be understood by those skilled in the art that various changes may be made, and equivalents may be substituted for the elements thereof without departing from the scope of the disclosure. In addition, many modifications may be made to adapt the teaching of the disclosure to particular use, application, manufacturing conditions, use conditions, composition, medium, size, and / or materials without departing from the essential scope and spirit of the disclosure. Therefore, it is intended that this disclosure is not limited to the exemplary embodiments and best mode contemplated for carrying out the embodiments of this disclosure as described herein. Since many modifications, variations, and changes in detail can be made to the described examples, it is intended that all matters in the preceding description and shown in the accompanying figures be interpreted as illustrative and not in a limiting sense.

Claims

WHAT IS CLAIMED IS:

1. A trencher for cutting a trench into a trenching surface, the trencher comprising: a rotatable cutting wheel; a motor for rotating the cutting wheel; a shroud assembly, the rotatable cutting wheel being at least partially disposed within the shroud assembly; a lift frame for raising and lowering the cutting wheel and shroud assembly; a lift frame actuator for moving the lift frame from a transport position to a lowered, trenching position; a skid connected to the lift frame for contacting the trenching surface during trenching operations, the skid being forward of the shroud assembly, the shroud assembly being moveable relative to the skid; and a downforce device that enables the skid to apply a downforce to the trenching surface during trenching operations, the downforce device being separate from the lift frame actuator.

2. The trencher as set forth in claim 1 wherein the lift frame actuator compresses the downforce device during trenching operations to cause the skid to apply a downforce to the trenching surface.

3. The trencher as set forth in claim 2 wherein the lift frame has a four- bar linkage, the shroud assembly being connected to the lift frame.

4. The trencher as set forth in claim 3 wherein the lift frame comprises a pull arm assembly, the actuator and downforce device being connected to the pull arm assembly, the downforce device being connected to the four-bar linkage.

5. The trencher as set forth in claim 4 wherein the pull arm assembly is pivotal relative to the four-bar linkage.

6. The trencher as set forth in claim 4 or claim 5 wherein the lift frame comprises a down-stop and an up-stop that limits travel of the pull arm assembly.

7. The trencher as set forth in any one of claims 3 to 6 comprising a mounting frame for connecting the trencher to a base vehicle, the lift frame being pivotally connected to the mounting frame about a vertical pivot axis, the mounting frame having a sliding assembly for moving the lift frame and shroud assembly laterally.

8. The trencher as set forth in any one of claims 1 to 7 wherein the downforce device is a spring element, pneumatic element, a hydraulic element or a combination thereof.

9. The trencher as set forth in any one of claims 1 to 8 wherein the shroud assembly comprises an inner shroud and an outer shroud, the rotatable cutting wheel being connected to the outer shroud, the outer shroud being moveable with respect to the inner shroud from a raised position to a lowered position.

10. The trencher as set forth in claim 9 wherein the cutting wheel and motor are connected by a shaft and the inner shroud comprises an arcuate slot, the shaft extending through the arcuate slot.

11. The trencher as set forth in claim 9 or claim 10 comprising a shroud actuator connected to the lift frame and to the outer shroud to move the outer shroud relative to the inner shroud.

12. A trencher for cutting a trench into a trenching surface, the trencher comprising: a rotatable cutting wheel; a motor for rotating the cutting wheel; a shroud assembly, the rotatable cutting wheel being at least partially disposed within the shroud assembly; a mounting frame for connecting the trencher to a base vehicle; a lift frame that pivotally connects the shroud assembly to the mounting frame for moving the cutting wheel and shroud assembly from a raised position to a lowered position; a pull arm assembly connected to the lift frame, the mounting frame, or both the lift frame and the mounting frame; and a lift frame actuator pivotally connected to the pull arm assembly to raise the shroud assembly when actuated in a first direction and causes the pull arm assembly to apply a force to a downforce device connected to the lift frame and the pull arm assembly.

13. The trencher as set forth in claim 11 wherein the lift frame is connected to a skid that contacts a trenching surface when the shroud assembly isin a trenching position, the downforce device enabling the skid to apply a downforce to the trenching surface during trenching operations.

14. The trencher as set forth in claim 13 wherein the skid is integral with the lift frame.

15. The trencher as set forth in claim 13 or claim 14 wherein the skid is forward of the shroud assembly.

16. The trencher as set forth in any one of claims 12 to 15 wherein the shroud assembly comprises: an inner shroud, the inner shroud comprising an arcuate slot, a shaft of the motor extending through the arcuate slot; and an outer shroud, the rotatable cutting wheel being connected to the outer shroud, the outer shroud being moveable with respect to the inner shroud from a raised position to a lowered position, the inner shroud being at least partially received in the outer shroud in the lowered position.

17. The trencher as set forth in any one of claims 12 to 16 comprising a vacuum system for removing spoil material from the shroud assembly, the vacuum system comprising a vacuum inlet that is replaceably removable from the shroud assembly.

18. The trencher as set forth in claim 17 wherein the vacuum inlet has a central axis that is tangential to the cutting wheel.

19. The trencher as set forth in claim 17 or claim 18 wherein the vacuum inlet has a central axis and the cutting wheel is configured to cut a trench having a forwardmost edge, the central axis being tangential to the forwardmost edge.

20. The trencher as set forth in any one of claims 12 to 19 wherein the downforce device is a spring element, pneumatic element, a hydraulic element, or a combination thereof.

21. The trencher as set forth in any one of claims 12 to 20 wherein the lift frame comprises a four-bar linkage.

22. The trencher as set forth in claim 21 wherein the lift frame comprises a down-stop and an up-stop that limits travel of the pull arm assembly.

23. A trencher for cutting a trench into a trenching surface, the trencher comprising: a rotatable cutting wheel; a motor for rotating the cutting wheel; a shroud assembly, the rotatable cutting wheel being at least partially disposed within the shroud assembly; a skid for contacting the trenching surface during trenching operations, the skid being forward of the shroud assembly, the skid being separate from the shroud assembly; and a downforce device that enables the skid to apply a downforce to the trenching surface during trenching operations.

Images