Patent Publication Number: US-2015068072-A1

Title: Trenching wheel with front-mounted cleaner

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims priority from U.S. Provisional Application Ser. No. 61/874,656, filed Sep. 6, 2013, entitled TRENCHING WHEEL WITH RIGID FRONT-MOUNTED CLEANER, the contents of which is hereby incorporated in its entirety by reference. 
    
    
     FIELD OF THE INVENTION 
     The invention relates generally to excavating machines, sometimes referred to as trenchers, of the type having a device for cutting the earth including a digging wheel assembly having a rim structure and a series of circumferentially spaced teeth, and more particularly to a cleaning device for removing spoil which has accumulated in the rim structure and teeth. 
     BACKGROUND 
     Excavating machines are 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 or trenching device. 
     It is also known for trenchers of the prior art to have a cleaning device. For example, some bucket wheel trenchers use a straight tooth cleaner which cuts a groove in the spoil which has accumulated in the rim structure and buckets to loosen the spoil so it will fall out of the rim structure and buckets and onto a conveyer which expels the spoil to a spoil bank beside the machine. This method is inefficient, especially when the spoil is packed in the rim structure and buckets due to high moisture or other causes. For example, in these trenchers, much of the spoil continues past the straight tooth cleaner and around the cutting wheel, thereby reducing the amount of spoil that can be removed. 
     U.S. Pat. No. 5,873,186 to Yoder et al. the contents of which are hereby incorporated by reference, describes an excavating machine with a positive cleaner for a U-shaped cutting wheel. The cleaning device positively cleans spoil out of the rim structure and buckets of the digging wheel assembly. The device includes a cleaning face which corresponds substantially in size and shape to the interior profile of the rim structure and the bucket. The cleaning face may be angled downward to force the spoil downwardly onto the conveyor. Moreover, the cleaning face may be biased into contact with the rim structure and bucket of the digging wheel assembly to force the spoil out of the rim structure and bucket. The Yoder et al. cleaner is located at the top of the trenching wheel in the frame. Accordingly, the buckets attached to the cleaning wheel travel through a portion of the frame prior to being cleaned. 
     While the above-described invention to Yoder et al. works well for U-shaped cutting wheels, devices including same are best suited for shallow trenches, such as those less than three feet deep. Deeper trenches require a different digging mechanism. Moreover, the cleaning mechanisms of the prior art are located at the top of the cutting wheel in the wheel frame. Such a configuration does not accommodate the amount of dirt and spoil in deeper trenches. Accordingly, an excavating device employing same becomes bogged down when attempting to dig deeper trenches. Center shank t-shaped buckets are also known. However, cutting wheels employing these buckets do not work well to dig deeper trenches, are slow, and also do not work well in sandy earth. 
     Therefore, there is a need in the art for an excavating a machine having an improved trenching assembly with a positive cleaning element which allows the machine to dig deeper trenches at faster rates. Furthermore, there is a need in the art for an improved digging or earth cutting mechanism which allows the machine to dig deeper trenches and dig trenches at faster rates. 
     SUMMARY 
     Disclosed is an excavating machine having an improved trenching or earth cutting assembly comprising a wheel, a plurality of teeth mounted on the wheel, and a frame retaining a portion of the wheel. Also included is a cleaning assembly. The cleaning assembly removes spoil from the earth moving assembly prior to the wheel entering the frame. The cleaning assembly may be located forward of the wheel (with the direction of forward travel of the trenching machine being the forward direction). In one embodiment, the excavating machine wheel is a T-shaped cutting wheel. Each of the plurality of teeth may include first and second cutting portions. One of the cutting portions may include a narrow leading edge, while the other cutting portion includes a wide leading edge. In some embodiments, the placement of the narrow and wide leading edges may alternate throughout the plurality of teeth. The cleaning assembly may include at least one side cleaning member which removes spoil from the plurality of teeth and the wheel. The cleaning assembly may further include a front cleaning member and/or at least one removable tooth. The cleaning assembly may include right and left cleaning assemblies. Furthermore, the cleaning assembly may include at least one spoil surface which moves spoil that has been removed by the cleaning assembly away from a trench being excavated by the machine. 
     Also provided is an excavating machine having an earth moving assembly including a wheel, a plurality of teeth mounted on the wheel, and a frame retaining an upper portion of the wheel. The teeth travel through the frame after moving earth and each include at least one cutting portion. The excavating machine may also include a cleaning assembly having at least one cleaning member which removes spoil from the at least one cutting portion. Furthermore, the cleaning assembly removes spoil from the earth moving assembly prior to the wheel entering the frame. The excavating machine may further include a spoil surface to remove spoil that has been cleaned by the cleaning assembly from the top of the trench being excavated. In addition, the plurality of teeth of the excavating machine may include first and second cutting portions, such as a first cutting portion with a narrow leading edge and a second cutting portion with a wide leading edge. The excavating machine may include right and left cleaning assemblies which may each have side and front cleaning members, as well as a removable tooth. 
     In addition, an excavating machine is provided comprising an earth moving assembly. The earth moving assembly may include a wheel, a plurality of teeth mounted on the wheel, and a frame retaining an upper portion of the wheel. Each of the plurality of teeth may include two cutting portions, with the first cutting portion having a narrow leading edge and the second cutting portion having a wide leading edge. The teeth may travel through the frame after moving earth. In addition, a cleaning assembly may be located forward of the wheel, with the cleaning assembly having right and left cleaning assemblies. The right and left cleaning assemblies may each include a side cleaning member, front cleaning member, and a removable tooth. The cleaning assembly may remove spoil from the earth moving assembly prior to the wheel entering the frame. In addition, the excavating machine may include two spoil surfaces which move spoil away from the top of a trench being excavated by the excavating machine. 
     Accordingly, a trenching machine of the present invention includes a positive cleaning element at the front of the cutting wheel. Moreover, the trenching machine of the present invention includes an improved cutting means. The cleaning mechanism positively cleans the earth moving assembly before dirt and spoil is able to move to, and become lodged in, the frame of the earth moving assembly. In the preferred embodiment, a cleaner, which may be rigid, is located on either side of the wheel; however, it is anticipated that other designs may be employed, as will be discussed in further detail herein. 
     The excavating machine of the present invention also includes means for pushing cleaned spoil away from the top of the trench. This prevents the spoil from falling back into the trench as the machine digs same. In another embodiment, an auger or conveyer may be used to move dirt away from the trench. The assembly of the present invention may be used to dig trenches deeper and faster than excavating devices of the prior art. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an elevation view of an excavating machine of the present invention in the lowered position at the bottom of a trench. 
         FIG. 2  is an elevation view of the cutting wheel and frame assemblies of the excavating machine of  FIG. 1 . 
         FIG. 3  is a perspective view of the teeth of the cutting wheel assembly of  FIGS. 1 and 2 . 
         FIG. 4A  is a side elevation view of a tooth of the cutting wheel assembly of  FIGS. 1-3 . 
         FIG. 4B  is a side elevation view of the opposite side of the tooth of the cutting wheel assembly of  FIG. 4A . 
         FIG. 5  is a front elevation view of two teeth of the cutting wheel assembly of  FIGS. 1 and 2 . 
         FIG. 6  is a side perspective view of a preferred embodiment of the cleaning assembly of the excavating machine of  FIG. 1 . 
         FIG. 7  is a side elevation view of the cleaning assembly of  FIG. 6 . 
         FIG. 8  is a side elevation view of the opposite side of the cleaning assembly of  FIG. 7 . 
         FIG. 9  is a side perspective view of a second embodiment of a cleaning assembly of an excavating machine of the present invention. 
         FIG. 10  is a side elevation view of the second embodiment of a cleaning assembly of  FIG. 9 . 
         FIG. 11  is a perspective view of a spoil arm of the excavating machine of  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION 
     The following is a detailed description of an excavating machine  100  having a trenching wheel  108  (also called an earth cutting wheel or cutting wheel) with a front-mounted cleaner. In the preferred embodiment, the front-mounted cleaner is rigidly attached to the machine  100 , although it need not be as will be discussed in further detail below. The machine includes an improved earth cutting or trenching assembly  106 , including a cutting wheel  108  with teeth  110  and a front-mounted cleaning assembly  136  (sometimes “cleaning assembly”). The trenching wheel and cleaning assembly are designed for use with an excavating machine (sometimes “machine”); however, it is anticipated that other uses of such an assembly may exist. References to direction, particularly forward of the cutting wheel or in front of the cutting wheel, refer to the direction which is in front of the excavating machine or in which the excavating machine travels in the forward direction unless otherwise provided. 
     Referring to  FIG. 1 , a trenching machine  100  of the present invention is shown. The trenching machine  100  includes a power unit vehicle  102 . In the illustrated embodiment, the power unit vehicle  102  is supported by wheels  104 . It will be appreciated by one skilled in the art that power unit vehicles  102  other than the type illustrated, as well as means for movement other than the illustrated wheels  104  may be employed by a trenching machine  100  of the present invention. The power unit vehicle  102  may be powered by any means known in the art, now or in the future, such as a typical motor. Also included is an earth cutting or trenching assembly  106 . Also shown in  FIG. 1 , the trenching assembly further includes a trenching wheel  108 . The trenching wheel  108  includes a plurality of circumferentially spaced teeth  110  located on a rim  112 . As will be discussed in further detail below, the trenching assembly  106  is shown in its lowered position at the bottom of a trench  120 . Also shown is a frame  114 , which is connected to the power unit  102  either directly or via one or more arms  116 . The frame  114  supports the trenching wheel  108 . Also shown is a cleaning assembly  136 . As will be discussed in further detail below, the cleaning assembly  136  is a front-mounted cleaner, which is preferably rigid. Accordingly, the cleaning assembly  136  removes spoil from the teeth  110  and wheel  108  prior to these components entering the frame  114 . Operably connected to the frame is a first spoil arm  126 , also called a spoil surface. As will be discussed below, a symmetrical spoil arm is also located on the opposite side of the machine  100 . Moreover, as will also be discussed in further detail below, the spoil arms  126  move spoil away from the trench  120  that is being dug by the machine  100 . 
     The trenching machine  100  further includes a shoe assembly  118 . The shoe assembly  118  is operably connected to the rear  124  of the frame  114 . The shoe assembly further includes a first side plate  122  and a second side plate (not shown) for contact with the side walls of the trench  120 . The contact of the shoe assembly  118  with the side walls of the trench  120  reduces and/or prevents a cave-in of the side walls of the trench  120  during use of the machine  100 . 
     The trenching assembly  106  is movable between raised and lowered positions.  FIG. 1  illustrates the trenching assembly  106  in the lowered position at the bottom of a trench  120  which is being dug by the machine  100 . Arrow A shows the direction of movement of the trenching assembly  106  to the raised position. In the raised position, the trenching assembly  106  is located above ground level. The trenching assembly  106  may also be located at any position between the fully raised and lowered positions. The raising and lowering of the trenching assembly  106  may be by any method known in the art, now or in the future. One such method is disclosed in U.S. Pat. No. 6,055,750, the entire contents of which are hereby incorporated by reference, which employs an arm assembly that is raised and lowered via a hydraulic cylinder. 
     Referring to  FIG. 2 , the trenching assembly  106  is shown in further detail. Shown is the trenching wheel  108  having a rim  112  and plurality of circumferentially spaced teeth  110 . In the preferred embodiment, the wheel  108  is a center shank T-shaped cutting wheel. However, it is anticipated that other types of wheels may be used without departing from the scope of the present invention. Preferably, the teeth  110  are mounted to a center shank ring. The wheel  108  is supported internally by a plurality of wheel support members  130 , which are rigidly connected to the frame  114 . Further, a plurality of wheel support rollers  132  are connected to the plurality of wheel support members  130 . The wheel support rollers  132  contact the rim  112 , allowing the rim  112 , and therefore the wheel  108 , to turn or travel around the rollers  132  and wheel support members  130 . Turning of the wheel  108  about the wheel support rollers  132  may be driven by a drive mechanism, which in the preferred embodiment is a drive motor  134 . The wheel is turned via the drive motor  134  in the direction of arrow B, such that the teeth  100  contact the ground to dig the trench  120 . 
     Also shown is the frame  114 . The wheel  108  is connected to the frame  114  such that the wheel  108  may turn or rotate with respect to the frame  114 . Specifically, as discussed above, the wheel support members  130  may be rigidly connected to the frame  114 . Therefore, the wheel  108  may turn about the wheel support members  130  and wheel support rollers  132  while remaining appropriately positioned with respect to the frame  114 . The frame  114  is operably connected to the power vehicle unit  102  such that the trenching assembly  106 , including but not limited to the frame  114  and wheel  108 , may be raised and lowered as discussed above. To that end, the frame may be connected to the power unit vehicle  102  via at least one arm  116 . In the preferred embodiment, the arm  116  is a hydraulic arm which may be shortened and lengthened in order to raise and lower the trenching assembly  106 . Furthermore, in the preferred embodiment, the machine  100  includes a set of two parallel hydraulic arms. Of course, as one of skill in the art will appreciate, other methods of raising and lowering the trenching assembly  106  may be employed. In addition, other means of connecting the trenching assembly  106  to the power unit vehicle  102  may be used, as well as other mans for connecting the wheel to the frame  114  and/or power unit vehicle  102 . 
     Also connected to the frame  114  is a cleaning assembly  136 . The cleaning assembly  136  includes a front-mounted cleaner. Therefore, the cleaning assembly  136  is located in front of, or toward the direction of travel, with respect to the frame  114 . Therefore, following the direction of arrow B, the teeth  110  of the trenching assembly  106  reach the cleaning assembly  136  prior to entering the frame  114 . It follows, then, that the teeth  110  and corresponding portion of the wheel  108  are cleaned prior to entering the frame  114 . Therefore, cleaning occurs before dirt and spoil is able to move to, and become lodged in, the frame. There are a number of advantages to such a configuration. First, the positive cleaning element allows the machine to dig deeper trenches. Furthermore, the positive cleaning element allows the machine to dig trenches faster. In addition, such a cleaning assembly is more effective in sandy soils than trenching machines of the prior art. The cleaning assembly  136  includes both a right side cleaning assembly  138  (not shown in  FIG. 2 .) and a left side cleaning assembly  140  (looking in the direction of travel). Shown in  FIG. 2  is the preferred embodiment of the left side cleaning assembly  140 , which may be symmetrical to the right side cleaning assembly. In the preferred embodiment, each of the right cleaning assembly  138  and left cleaning assembly  140  includes a side cleaning member and a front cleaning member. Shown in  FIG. 2  is the left side cleaning member  142  and left side front cleaning member  144 . 
     Also shown is the first spoil arm  126 . As discussed above, the machine  100  includes two spoil arms  126 , one of which is shown in  FIG. 2 . The spoil arms  126 ,  128  are configured to move dirt and spoil away from the top of the trench  120 . Therefore, the spoil arms  126 ,  128  prevent dirt and spoil which is cleaned from the trenching assembly  106  or which is otherwise present at the top of the trench  120  from falling back into the trench. In addition to the spoil arm  126  shown in  FIG. 2 , a second spoil arm may be located on the opposite side of the machine  100 . The second spoil arm may be symmetrical to the spoil arm  126  shown in  FIG. 2 . 
     As discussed above, preferably, the teeth  110  are mounted to a center shank ring. Trenching assemblies and wheels of the prior art include U-shaped buckets. Accordingly, the bucket digs into the earth and removes a portion of same, which is carried in the bucket until it falls or is cleaned out of the bucket. The teeth  110  of the present invention include an improved shape. As shown in  FIG. 3 , the teeth  110  may include a center support portion  150  and at least one cutting portion  151 , which extends to one or both sides of the center support portion  150 . The teeth  110  are generally an upside down triangle shape. In the preferred embodiment, the teeth each may include two cutting portions  151 . In addition, the teeth  110  may be offset from the center, which is more clearly shown in  FIG. 5 . As shown in  FIG. 3 , the teeth  110  cutting portions  151  may have a narrow leading edge  152  or a wide leading edge  154 . Moreover, as can be seen in  FIG. 3 , alternating teeth  110  may alternate with respect to whether the narrow edge  152  or wide edge  154  is located to the right or the left. In the preferred embodiment, however, the narrow leading edge  152  is generally centered or nearly centered on the wheel  108 , the advantage of which will be discussed below. 
     Both the narrow edge  152  and wide edge  154  of the cutting portions  151  may be sharp so as to dig into the ground. As mentioned above, the narrow edge  152  cutting portion  151  and wide edge  154  cutting portion  151  of each tooth  110  may alternate. Such an arrangement is beneficial for removing larger pieces of earth. For example, a leading narrow edge  152  cutting portion  151  will cut a groove in the earth. The next tooth will have a wide edge  154  cutting portion  151  where the preceding narrow edge  152  has cut the groove, thereby spreading the size of the groove. Alternating the narrow edge  152  cutting portion  151  and wide edge  154  cutting portion  151  results in less friction than using cutting portions  151  of the same size because fewer and smaller cutting edges are rubbing underneath the dirt. Moreover, the placement of the teeth  110  with respect to the wheel  108  may vary so as to further dig beside the initially-dug groove and widen the trench that is cut by the preceding cutting portions  151 . 
     It is anticipated that the cutting portions may be of any width and sharpness. Moreover, it is anticipated that there may be embodiments where the narrow edge  152  and wide edge  154  are in a different configuration, such as not alternating, without departing from the scope of the invention. It is anticipated that different configurations may be advantageous in varying types of soil. For example, the teeth  110  of the present invention may also be used with a rock tip, such as a carbide rock tip, which may be advantageous in rocky soils. In addition, the trenching wheel  108  of  FIGS. 1-3  includes a cutout  156  between each tooth  110 , as shown in  FIG. 3 . In one embodiment, a cutout  156  may only be included between every third tooth  110 . It is anticipated that the latter configuration may be advantageous in rocky soils, as rocks may become caught in these cutouts  156 . However, it is anticipated that any configuration may be used without departing from the scope of the invention. 
       FIG. 4A  provides a side view of an embodiment of a tooth  110  of the present invention. Specifically, the side of the narrow leading edge  152  is shown. Furthermore,  FIG. 4B , provides a side view of an embodiment of a tooth  110  wherein the wide leading edge  154  is shown. As discussed above, in the preferred embodiment, the narrow leading edge  152  and wide leading edge  154  alternate left and right sides of the teeth  110  projected from the center support portion  150 . This configuration is shown in  FIG. 5 . Furthermore, in the preferred embodiment, the narrow leading edges  152  are located at or near the center line  158  of the wheel  108 . As discussed above, this configuration presents an improvement over the prior art and leads to more efficient trenching, allowing a user to dig trenches faster and trenches which are deeper. 
     Returning to  FIG. 2 , the cutting wheel  108  turns in the direction of arrow B. Accordingly, as the excavating machine  100  moves forward in the direction of arrow C, a trench  120  is created behind the machine  100 . The plurality of teeth  110  cut into the dirt and move same from the trench  120 . In addition, the shoe assembly  118  (shown in  FIG. 1 ), including the two side plates  122 , contact the side of the trench  120  immediately after it is dug by the trenching assembly  106  in order to prevent a cave-in of the side walls of the trench during use of the excavating machine  100 . 
     As shown in  FIGS. 1 and 2 , the trenching machine  100  of the present invention also includes an improved cleaning assembly  136 . Detail of a preferred embodiment of an improved cleaning assembly  136  is shown in  FIGS. 6-8 . The cleaning assembly  136  is located near the front, or lead side, of the wheel  108  (in the direction of arrow C shown in  FIG. 2 ). Because the cleaning assembly  136  is located forward and underneath the frame  114 , the wheel  108  and teeth  110  are cleaned prior to the teeth  110  entering the cutting wheel frame  114 . Therefore, spoil does not collect in the frame  114 . A side view of the left side of the machine  100  (when facing the direction of forward travel shown by arrow C of  FIG. 2 ) showing the left side cleaning assembly  140  is provided in  FIG. 6 . As discussed below, it will be appreciated that similar components are found on the right side of the machine  100 . 
     The left side cleaning assembly  140  includes a left side or side cleaning member  142  and a left side front or left front cleaning member  144 . The left side cleaning assembly  140  may be rigidly attached to the frame  114 . Specifically, in the embodiment illustrated in  FIG. 6 , the side cleaning member  142  may be rigidly attached to the frame  114  using any method known in the art now or in the future. Alternatively, the cleaning assembly  136 , including the left cleaning assembly  140 , need not be rigidly attached to the frame  114  or attached to the frame  114  at all without departing from the scope of the invention. For example spring-loaded or hydraulic powered cleaners may be used without departing from the scope of the invention. The left side cleaning member  142  may be a side plate or plate as shown in  FIG. 6  which is located in close proximity to the wheel  108  and which corresponds in shape to the wheel  108  so as to scrape dirt and spoil off of the wheel. Furthermore, as a tooth  110  travels through the cleaning assembly  136  the narrow leading edge  152  travels between the left cleaning assembly  140  and right cleaning assembly  138  (discussed in further detail below). Therefore, the two cleaning assemblies  138 ,  140  work in cooperation to scrape dirt and spoil from the narrow leading edge  152  cutting portion  151 . 
     Furthermore, the wide leading edge  154  travels outside of the cleaning assembly  136 . As discussed above, and shown in  FIG. 5 , the teeth  100  are offset from the center, and the wide leading edge  154  alternates between being located to the left or right of the wheel  108  center line  158 . Accordingly, the wide leading edge  156  travels outside of the cleaning assembly  136 . Depending on whether the wide leading edge  156  is located to the left or right of the center line  158 , the wide leading edge  156  travels outside of the respective right cleaning assembly  138  or left cleaning assembly  140 . Accordingly, as the two teeth cutting portions  151 , which in the preferred embodiment include a narrow leading edge  154  and wide leading edge  156  travel on either side of one of the two right  138  and left  140  cleaning assemblies, the cleaning assembly cleans each tooth  110  between the cutting portions  151 . In addition, the teeth  110  are cleaned prior to entering the frame  114 . Moreover, the wide leading edge  156  and wheel  108  are also cleaned prior to entering the frame  114 . 
     In the preferred embodiment shown in  FIG. 6 , the left side cleaning member includes a front portion  160  and a back portion  162 . The front portion  160  and back portion  162  are at an angle to each other. Preferably, the back portion  162  is generally parallel or at a small angle to the rim  112  of the wheel  108  in order to scrape spoil off of the rim. The front portion  160  is generally perpendicular to the rim  112  and also the direction of travel of the machine  100 , which is indicated by arrow C in  FIG. 2 . The left side front cleaning member  144  may be attached to the frame  114 , left side cleaning member  142 , or both. In the embodiment shown in  FIG. 6 , the left side front cleaning member  144  is directly attached to the left side cleaning member  142 . Specifically, the front cleaning member  144  is located and attached underneath the left side cleaning member front portion  160  and beside the left side cleaning member back portion  162 . Furthermore, in an alternate embodiment, the left side cleaning member  142  may be configured so as to provide the function of the spoil arm  126 , which is discussed in further detail below. For example, the left side cleaning member  142  may be extended down, back, and/or out to the side of the machine  100  to push the dirt and spoil away from the trench  100 . In such a configuration, the left side cleaning member  142  could resemble a wing. 
     Returning again to the illustrated preferred embodiment, the cleaning assembly  136  and specifically the left side cleaning assembly  140  may further include a removable tooth  164 , which may be attached to the bottom of the left side front member  144  and located at or near the bottom of both the left side front member  144  and left side cleaning member  142 . It will be understood that preferably the tooth  164  is removable, although a non-removable or permanent tooth may be employed without departing from the scope of the invention. The tooth  164  may be made of steel or any other material suitable for the application, which will be understood by one of skill in the art. The advantage of a removable tooth  164  is that the tooth  164  may be replaced if necessary, such as due to damage or wear, without replacing the entire cleaning assembly  136  or respective side cleaning assembly. 
       FIG. 7  provides an elevation view of the left side cleaning assembly  140 . Shown are the left side cleaning member  142  and front cleaning member  144 . Both the back portion  162  and front portion  164  of the left side cleaning member  142  may be seen. Also shown is the left side removable tooth  164 . The left cleaning assembly  140  is attached to the frame  114 , which is also connected to the plurality of wheel support members  130 . Attached to the wheel support members  130  are the wheel support rollers  132 , about which the wheel  108  travels. As discussed above, the teeth  110  extend outside of the wheel  108  from the rim  112  and include a center support portion  150  and cutting portion  151 . Shown is a cutting portion  151  having a narrow leading edge  152 . 
       FIG. 8  illustrates an elevation view of the right side cleaning assembly  138 . In the preferred, illustrated embodiment, the right cleaning assembly  138  and left cleaning assembly  140  are symmetrical. Accordingly, the above discussion of the left side cleaning assembly  140  is relevant to the right side cleaning assembly  138  and will not be repeated in detail, including potential alternate embodiments of the machine  100  and/or cleaning assembly. However, it will be understood by one of skill in the art that the right  138  and left  140  cleaning assemblies need not be symmetrical. Shown in  FIG. 8  is the frame  114  to which the right side cleaning assembly  138  is preferably rigidly attached. Also shown is a tooth  110  including a support portion  150  and a cutting portion  151 , which includes a narrow leading edge  152 . As discussed above, the cutting portion  151  could also include a wide leading edge  154 , which would travel outside of the cleaning assembly  138 . The cleaning assembly includes a right side cleaning member  146  and a right side front cleaning member  148 . Furthermore, the right side cleaning member  146  includes a front portion  166  and back portion  168 . The back portion  168  is rigidly connected to the frame  114 , although the cleaning assembly  138  need not be non-rigidly connected to the frame  114  or not directly connected to the frame  114  at all. Alternatively, the cleaning assembly  138  may be attached to the frame by any other method known in the art now or in the future. Further, the frame  114  is connected to the plurality of wheel support members  130  and wheel support rollers  132  about which the wheel  108  turns. Moreover, the right cleaning assembly  138  includes a removable tooth  170 . The tooth  170  need not be removable; however, as discussed above, employing a removable tooth  170  has the benefit of ease of repair and replacement. 
       FIGS. 9-10  illustrate a second embodiment of a cleaning assembly  172  and specifically the left cleaning assembly  174  of the second embodiment  172 . The right side of the cleaning assembly  172  is preferably symmetrical to the left cleaning assembly  174 . Accordingly, the right side of the cleaning assembly will not be illustrated or discussed in detail, as the discussion of the left cleaning assembly  174  is relevant to the right side. However, it will be understood by one of skill in the art that the left and right sides need not be symmetrical. The illustrated second embodiment of the cleaning assembly includes a single left cleaning plate  176 . The left cleaning plate  176  includes a front portion  178  and back portion  180 . The front portion  178  is generally perpendicular to the wheel  108  and direction of travel. The back portion  180  is generally parallel or at a small angle to the wheel  108  so as to clean same, such as by scraping the dirt and spoil off the wheel  108 . However, one of skill in the art will recognize that the left cleaning plate  176  may be at any angle to the wheel  108  that allows the wheel  108  to be cleaned. Furthermore, one of skill in the art will recognize that the left cleaning plate  176  need not include multiple portions and may be configured in any arrangement which results in removing at least a portion of the dirt and spoil from the wheel  108 . 
     Also shown is the frame  114  to which the cleaning assembly  172 , including the left cleaning plate  176 , is preferably attached, as well a wheel support roller  132  about which the wheel  108  turns. Further included is a tooth  110 , which is attached to the rim  112  of the wheel  108 . The tooth  110  includes a center support portion  150  and two cutting portions  151 . The tooth includes both a narrow leading edge  152  cutting portion and a wide leading edge  154  cutting portion. 
     The preferred embodiment of the excavating machine  100  also includes a pair of spoil arms.  FIG. 11  provides a view of the left spoil arm  126 . It will be understood by one of skill in the art that, in the preferred embodiment, the right spoil arm is symmetrical to the left spoil arm  126 . Accordingly, it will not be shown or discussed in detail. However, it will also be understood by one of skill in the art that the right and left spoil arms need not by symmetrical. The spoil arm  126 , which may also be seen in  FIGS. 1 and 2 , push spoil away from the top of the trench  120 , including spoil which has been removed by the cleaning assembly  136  or  172 . Accordingly, cleaned spoil does not fall back into the trench  120 . In the illustrated embodiment, the spoil arm  126  is a foldable arm that includes at least a portion which is generally at an angle to the wheel  108  so as to push spoil out and away from the top of the trench  120 . As one of skill in the art will recognize, the spoil arm  126  may be any shape, size, or assembly that serves the purpose of pushing soil away from the top of the trench  120 . For example, in an alternative embodiment, hinged assemblies could be used, such as those having a general shape of a less than sign (“&gt;”). In another embodiment, the spoil arm  126  may be rigid rather than foldable or hinged, such as by a rigid connection to the frame  114 . In addition, it is anticipated that the cleaning assembly  136  or  172  could be used with an auger or conveyer (not shown) to move dirt out of the machine  100  and away from the trench  120 . The spoil arm  126  may be connected to the frame  114 , such as by a rotatable connection  186 . Accordingly, the spoil arm  126  may be located in a lowered position, shown in solid lines in  FIG. 11  or a raised position, shown in dotted lines in  FIG. 11 . 
     By utilizing the improved teeth  110  and placing a positive cleaner at the front of the cutting wheel  108  and frame  114 , the trenching machine  100  herein disclosed provides a means for digging deeper trenches and for digging trenches faster than prior art trenching machines. For example, in one embodiment, a four foot trench may be dug at a rate of 75-100 feet per minute or faster. Machines of the prior art generally dig a 4 feet deep trench at 50 feet per minute if even capable of digging a trench deeper than 3 feet. Moreover, trenches six feet deep may be dug. 
     Although various representative embodiments of this invention have been described above with a certain degree of particularity, those skilled in the art could make numerous alterations to the disclosed embodiments without departing from the spirit or scope of the inventive subject matter set forth in the specification and claims. Joinder references (e.g. attached, adhered, joined) are to be construed broadly and may include intermediate members between a connection of elements and relative movement between elements. As such, joinder references do not necessarily infer that two elements are directly connected and in fixed relation to each other. In some instances, in methodologies directly or indirectly set forth herein, various steps and operations are described in one possible order of operation, but those skilled in the art will recognize that steps and operations may be rearranged, replaced, or eliminated without necessarily departing from the spirit and scope of the present invention. It is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative only and not limiting. Changes in detail or structure may be made without departing from the spirit of the invention as defined in the appended claims. 
     Although the present invention has been described with reference to the embodiments outlined above, various alternatives, modifications, variations, improvements and/or substantial equivalents, whether known or that are or may be presently foreseen, may become apparent to those having at least ordinary skill in the art. Listing the steps of a method in a certain order does not constitute any limitation on the order of the steps of the method. Accordingly, the embodiments of the invention set forth above are intended to be illustrative, not limiting. Persons skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention. Therefore, the invention is intended to embrace all known or earlier developed alternatives, modifications, variations, improvements, and/or substantial equivalents.