Patent Publication Number: US-2006011357-A1

Title: Edging and trenching system

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
      This patent application claims the benefit of U.S. Provisional Patent Application No. 60/588,897, filed Jul. 16, 2004. 
    
    
     FIELD OF THE INVENTION  
      This invention pertains generally to landscape bed edgers and more particularly to combination landscape bed edgers and cable layers. The invention finds particular applicability in the field of commercial landscaping.  
     BACKGROUND OF THE INVENTION  
      Edgers have been used in many landscaping applications to create landscape beds, for example around flower beds, decorative gardens, pools, or trees. Edgers create well-defined edges around a bed by cutting the soil to a depth of several inches. The displaced soil is moved outwardly away from the edger, creating a clean definition of the bed edge.  
      Cable layers have been used to dig a narrow trench and bury cable wire in the trench. Cable layers are useful to lay pet fence or landscape lighting.  
     BRIEF SUMMARY OF THE INVENTION  
      The invention provides a combination bed edger and cable layer having a common platform and interchangeable cutting wheels and shrouds. The bed edger shroud has a pentagon shape with an open bottom and includes baffle plates on its inside surface to direct soil away from the bed edger unit. The bed edger shroud is attachable to the bed edger using knobs, and therefore can be attached and removed from the bed edger without the use of tools. Thus, the operator can remove the shroud without tools in order to clean the edger or change the blade. In this way, the bed edger shroud can be easily removed by an operator without tools, and the cable layer shroud can be easily attached when the operator desires to change applications. The cable layer shroud is also attachable and removable through easy to use knobs.  
      The bed edger shroud has a pentagon shape that directs displaced soil toward the outside of the bed edger. The pentagon shape is strong and easy to manufacture.  
      Both shrouds are provided with a pivot pin through which the bed edger shroud or the cable layer shroud can be pivoted. An operator can thereby remove the knobs and pivot the shroud, exposing the interior surface of the shroud for cleaning purposes, and exposing the cutting blade for replacement, maintenance, and cleaning purposes.  
      For quick change capability between bed edger applications and cable layer applications, the bed edger cutting blade and the cable layer cutting blade are both easily attachable and removable from the drive shaft through a pilot nose mounting arrangement. The pilot nose mounting arrangement allows the cutting blades to be mounted to the drive shaft by bolts on the face of the cutting blade. This allows the operator easy access to loosen and remove the bolts and the cutting blade without the need to clamp the tool drive shaft.  
      The bed edger unit includes a chain drive that provides a direct link between an engine output shaft and the cutting blade drive shaft through a centrifugal clutch. The direct link chain drive supplies reliable power for heavy duty cutting, for example through tree roots. The centrifugal clutch provides a safety release of the drive shaft, for example when the cutting blade hits a rock.  
      The bed edger unit includes a release lever mounted on the handle that allows an operator to convert the unit from an operating position to a transport position. An operator can easily move from one bed to another without having to adjust the unit from the front and without having to move the unit on only two wheels. Moreover, the operating depth of the cutting blade can be modified to dig deeper or shallower ditches.  
      The fully adjustable and folding handle allows for easy transport, storage and comfortable working height. The adjustable handle can be adjusted to one of several heights allowing an operator to customize the unit to his own preferences. The folding handle allows the unit to be conveniently stored without taking up too much storage space.  
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)  
       FIG. 1  is a perspective view of the device configured as a bed edger.  
       FIG. 2  is a perspective view of a device configured as a cable layer.  
       FIG. 3  is a perspective view of the device with a protective shroud removed and with a cutting blade tool removed.  
       FIG. 4  is a top view of the device configured as a bed edger.  
       FIG. 5  is a top view of the device configured as a cable layer.  
       FIG. 6  is a side view of the device configured as a bed edger.  
       FIG. 7  is a side view of the device configured as a cable layer.  
       FIG. 8  is a rear view of the device configured as a bed edger.  
       FIG. 9  is a rear view of the device configured as a cable layer.  
       FIG. 10  is a perspective view of the device shown from a side opposite the cutting blade tool.  
       FIG. 11  is an exploded view of a bed edger shroud and bed edger cutting blade.  
       FIG. 12  is a top view of a bed edger shroud.  
       FIG. 13  is a side view of a bed edger shroud.  
       FIG. 14  is a rear view of a bed edger shroud.  
       FIG. 15  is a perspective view of a bed edger shroud.  
       FIG. 16  is an exploded view of the chain drive, frame and housing assemblies.  
       FIG. 17  is an exploded view of the unit and the bed edger shroud.  
       FIG. 18  is a perspective view of a cable layer shroud.  
       FIG. 19  is an exploded view of a cable layer shroud and cable layer cutting blade.  
       FIG. 20  is an exploded view of a chain drive assembly.  
       FIG. 21  is a view of a chain drive assembly mounted to the unit.  
       FIG. 22  is an exploded view of a handle assembly.  
       FIG. 23  is a side view of the unit showing the handle assembly in a first and second position.  
       FIG. 24  is an exploded view of a steering axle assembly for the device.  
       FIG. 25  is a view of the steering axle in a locked position.  
       FIG. 26  is a view of the steering axle in an unlocked position.  
       FIG. 27  is an exploded view of a rear axle assembly.  
       FIG. 28  is a view of the rear axle assembly.  
       FIG. 29  is a side view of the rear axle assembly from the outside in the operating position.  
       FIG. 30  is a side view of the rear axle assembly from the outside in the transport position.  
       FIG. 31  is a side view of the rear axle assembly from the inside in the operating position.  
       FIG. 32  is a side view of the rear axle assembly from the inside in the transport position.  
       FIG. 33  is a perspective view showing the rear axle assembly in a first and second position.  
       FIG. 34  is a perspective view of another embodiment of a bed edger shroud.  
       FIG. 35  is a perspective view of another embodiment of a cable layer shroud.  
       FIG. 36  is an exploded view of another embodiment of the device having a bed edger shroud and a cable layer cutting blade.  
       FIG. 37  is rear view of the device in  FIG. 32  having a bed edger shroud and a cable layer cutting blade. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
      A convertible bed edger and cable layer unit  50  is shown generally in  FIGS. 1-3 . The unit or ground digging device  50  has a common platform with interchangeable cutting blades and protective shrouds. The unit  50  includes an engine  52 , front wheels  54 ,  56 , rear wheels  58 ,  60 , a bed edger shroud  100 , a bed edger tool  150 , a cable layer shroud  200 , a cable layer tool  250 , a handle assembly  300 , a steering axle assembly  330 , a rear axle assembly  400 , and a frame  500 .  
      The engine  52 , which can be either an internal combustion engine or an electric motor, provides power to the unit and drives the cutting blade tool. The handle assembly  300  is attached to the frame  500  through the steering axle assembly  330 .  FIG. 3  shows the unit  50  without a protective shroud or cutting blade tool attached. Knobs  132 ,  133  are provided for easily attaching or removing a protective shroud to the frame  500 . Mounting hub  158  includes a pilot nose, 3-bolt attachment feature to easily attach or detach a cutting blade to the unit. Thus, the common platform as shown in  FIG. 3  can be easily configured as either a bed edger as shown in  FIG. 1 , or a cable layer as shown in  FIG. 2 .  
       FIGS. 4-5  show a top view of the unit  50  configured as a bed edger and configured as a cable layer, respectively.  FIGS. 6-7  show a side view of the working side of the unit  50  configured as a bed edger and configured as a cable layer, respectively.  FIGS. 8-9  show a rear view of the unit  50  configured as a bed edger and configured as a cable layer, respectively.  FIG. 10  shows a perspective view of the unit  50  from a side opposite the working side of the unit.  
      A bed edger shroud  100  is shown generally in  FIGS. 11-15 . The bed edger shroud includes a body  102 , attachment holes  114  and  116 , an attachable rear flap  118 , an attachable main flap  120 , a handle  122 , mounting tabs  130  and a plurality of baffle plates  140 ,  142 , and  144 .  
      The bed edger shroud body  102  has a pentagon shape with an open bottom side, which allows for the removal of dirt. The body  102  includes angled top surfaces  104  and  106 , angled side surfaces  108  and  110 , and a rear surface  112 . Referring to  FIGS. 12-14 , baffle plates  140 ,  142 , and  144  are welded to the interior surface of the shroud body  102 . Baffle plates  140 ,  142 , and  144  are advantageously placed within the interior of the shroud body  102  to efficiently direct the flow of dirt to the side of the bed edger unit. The shape of the shroud body  102  also advantageously directs the flow of dirt to the side of the bed edger unit. The pentagon shaped shroud body is easier and less expensive to manufacture, in comparison to a similar round type design.  
      Referring to  FIG. 11 , the angled side surfaces  108  and  110  include a plurality of attachment holes  116  for the attachment of a main flap  120 . The main flap  120  can be attached to the body  102  through bolts or other attachment devices. Similarly, rear surface  112  includes a plurality of attachment holes  114  for the attachment of rear flap  118 . The rear flap  118  can be attached to the body  102  through bolts or other attachment devices. The main flap  120  and the rear flap  118  further direct the flow of dirt towards the side of the bed edger unit. Advantageously, main flap  120  can be removed to allow replacement of the flap  120 .  
       FIGS. 16-17  show an exploded view of the unit  50 . Chain cover housing  136  is attached to frame  500  with bolts. The chain cover housing  136  serves the dual function of providing a protective cover to the chain drive transmission and of providing an attachment location for the protective shroud. A handle  122  is secured to the top of the shroud body  102 , which allows an operator a convenient grip to remove the bed edger shroud  100 . The bed edger shroud  100  is attachable to the unit  50  through mounting tabs  130 , locating pins  134 , and threaded knobs  132 ,  133 . Four mounting tabs  130  are welded to the shroud body  102 . Locating pins  134  are secured to the chain cover housing  136  and include a nut and bushing arrangement  126 . The mounting tabs  130  include a slot  135 . The slots  135  fit over locating pins  134  and the nut and bushing arrangement  126 . In order to provide a secure connection for the shroud body  102 , a threaded bolt  122  passes through a hole in the chain cover housing  136  and through a hole in the mounting tabs  130 . Nut  124  secures the bolt to the chain cover housing. Knobs  132  include a threaded aperture that engages the threaded bolts  122 , thereby securing the bed edger shroud  100  to the unit  50 . Knobs  133  include threaded stud portion  139 , which engages a threaded aperture  141  on the chain cover housing  136 .  
      The construction allows an operator to easily attach and detach the bed edger shroud  100  to the unit without tools. Knobs  132 ,  133  can be removed manually by hand, and mounting tabs  130  can be slid off the chain cover housing  136 . An operator can simply unscrew the knobs  132 ,  133  and lift the edger shroud  100  off the unit by handle  122 . This design advantageously allows for greater convertibility of the unit. Bed edger shroud  100  can be removed when an operator wants to use the unit as a cable layer. Cable layer shroud  200  can then easily be attached to the frame. Moreover, the design allows an operator a quick and simple way to detach the shroud  100  in order to clean the interior surface of the shroud, or to gain access to the edger tool blade  150 .  
      A cable layer shroud  200  is shown generally in  FIGS. 18-19 . The cable layer shroud  200  is used when the unit is converted to its cable layer function. The cable layer shroud  200  includes a cable guard body  202 , a handle  222 , a spool shaft  204 , a tube  206 , a tube mounting plate  208 , and mounting tabs  230 . The spool shaft  204  is fixed to the top of the cable guard body  202  through holes  212  in protrusions  210 . The spool shaft is fixed using a pin  214  or any other attachment device.  
      Tube mounting plate  208  is fixed to the interior surface of the cable guard body  202  by bolts and wingnuts, or alternatively using any attachment device, and holds tube  206 . A roll of cable sits over the spool shaft  204 , and the cable passes through hole  216  located on the top surface of the cable guard body  202 , and through tube  206 , which directs the cable toward the ditch.  
      Referring to  FIGS. 18 and 19 , the mounting tabs  230  are used to secure the cable layer shroud  200 . A handle  222  is secured to the top of the cable guard body  202 , which allows an operator a convenient grip to remove the shroud. The cable layer shroud  200  is attachable to the unit  50  through mounting tabs  230 , locating pins  134 , and threaded knobs  132 ,  133  as shown in  FIGS. 16 and 17 . In this embodiment, four mounting tabs  230  are welded to the cable guard body  202 . The mounting tabs  230  fit over locating pins  134 . In order to provide a secure connection for the cable guard body  202 , knobs  132 ,  133  secure the mounting tabs to the chain cover housing.  
      Another embodiment of a bed edger shroud  1100  is shown in  FIG. 34 . Pivot pin  1146  is located on the surface of the bed edger shroud  1100 . The bed edger shroud  1100  can be pivoted away from the unit about the pivot pin  1146  when the knobs  132 ,  133  are removed. By unfastening the knobs  132 ,  133 , the bed edger shroud  1100  can be pivoted toward the front of the unit, so that the operator can gain access to the edger blade tool  150 . Similarly, a pivot pin  1246  can be provided on the cable layer shroud  1200 , as seen in  FIG. 35 . The cable layer shroud  1200  can be pivoted away from the unit about the pivot pin  1246  when the knobs  132 ,  133  are removed.  
      By pivoting either the bed edger shroud  1100  or the cable layer shroud  1200 , an operator can gain easy access to the interior surface of the shroud for cleaning purposes. The operator can also gain easy access to the cutting tool for either cleaning purposes or for maintenance purposes.  
      A bed edger tool  150  is shown generally in  FIG. 11 . The bed edger tool  150  includes a three-prong backplate  152 , a plurality of carrier plates  154  and a plurality of blades  156 . Three carrier plates  154  are welded to the three-prong backplate  152 . Blades  156  are attached to the carrier plates  154 . Bolts  162  fasten the bed edger tool  150  to a mounting hub  158 , which is connected to the tool drive shaft  178  through mounting hub  158 .  
      A cable layer tool  250  is shown generally in  FIG. 19 . The cable layer tool  250  includes a three-prong backplate  252  and three blades  256 . The cable layer tool  250  is secured to the mounting hub  158  with three bolts  162  that extend through holes  260  on the three prong backplate  252 .  
      Referring to  FIGS. 11 and 19 , The three bolt attachment feature on the backplates  152  and  252  of the bed edger tool  150  and the cable layer tool  250  allows an operator to quickly remove and replace the bed edger tool  150  or the cable layer tool  250 . Because the three bolts are located on the face of the tool, an operator has easy access to the bolts, allowing the operator to quickly remove the tool heads without the need to clamp the tool drive shaft.  
      The chain drive transmission is shown generally in  FIG. 20 . Mounting hub  158  is connected to drive sprocket  172  through drive shaft  178 . In this embodiment, the mounting hub  158  is attached to drive shaft  178  with a key  180  and set screws  182 .  
      Referring to  FIG. 21 , the engine drives an engine sprocket  170 . Engine sprocket  170  is connected to drive sprocket  172  through chain  174 . Chain  174  provides a direct connection from the engine output to the tool head input. Chain  174  also passes over and drives an idler sprocket  176 , which may be used to appropriately tension the chain  174 . Referring to  FIG. 20 , the drive shaft  178  is connected to drive sprocket  172  with a key  183  and a bolt attachment  184 .  
      Referring to  FIGS. 16 and 21 , a bearing attachment plate housing  188  is mounted on frame  500 . A bearing  186  is mounted to the bearing attachment plate housing  188 . The bearing  186  provides additional support for the drive shaft  178 .  
      Referring to  FIG. 21 , a centrifugal clutch  189  is provided between the engine output and the engine sprocket  170 . The clutch allows the engine to disconnect from the main drive when it appears that disconnect is needed, such as when the cutting tool encounters a hard object. The chain  174  provides a heavy duty reliable source of power to drive the edger blades  150  or the cable layer blades  250 .  
      Referring to  FIGS. 22-24 , a handle  300  comprises a first section  302  and a second section  304 . The first section  302  includes handlebars  305  attached at one end and a pivotable mounting hub  306  at the other end. The first section  302  is pivotable around axis  307  with respect to the second section  304 . The second section  304  is fixed to the steering axle assembly  330  at its lower end and includes a fixed mounting hub  308  at the upper end. The handle  300  may also include an operator presence lever  309 , a throttle lever  311  and a release lever  324 .  
      Pivotable mounting hub  306  is pivotably connected to the fixed mounting hub  308  with bolts  320 . Bolts  320  pass through holes  316  in the pivotable mounting hub  306  and holes  318  in the fixed mounting hub  308 . The attachment of the pivotable mounting hub  306  and the fixed mounting hub  308  by bolts  320  define the pivot axis  307  about which the first section  302  can pivot relative to the second section  304 . A plurality of holes  310  are also provided on the pivotable mounting hub  306  that define a second connection point between the pivotable mounting hub  306  and the fixed mounting hub  308 . In order to fix the handle bar at a discrete height, a spring pin  322  is inserted through one of the sets of holes  310  and through holes  312  in the fixed mounting hub  308 . Holes  314  are provided for use in a folding position of the handlebars.  
      Different operators of the unit  50  may desire the handlebars to be located at different heights.  FIG. 23  illustrates a first position  323  and a second position  325  for the handle  300 . Depending on the operator&#39;s height and the operator&#39;s strength, an operator may have a differing preference of where the handle  300  should be located. Even the same operator may desire the handle  300  at different heights for different applications. The handle  300  provides the adjustability to allow the operator to quickly change the height of the handle  300  by simply moving the spring pin  322 , pivoting the first section  302 , and reinserting the spring pin  322  through one of the plurality of holes  310  provided on the pivotable mounting hub  306 . In this way, the operator has multiple discrete options at which he can adjust the handle  300 . Moreover, by providing two connections between the pivotable mounting hub  306  and the fixed mounting hub  308  using the bolts  320  and the spring pin  322 , the handle  300  is not susceptible to slippage.  
      When an operator is finished using the unit  50 , the unit  50  is usually stored in a storage area, such as a garage, a tool shed, a trailer or a truck. Because space in such storage areas is often limited, it is desirable for the unit  50  to be stored in a compact state. The operator can fold the handle  300  over the unit  50  folded to position  327  as shown in  FIG. 23 . In order to fold the handle, the spring pin  322  is moved, the first section  302  of the handle  300  is pivoted and the spring pin  322  is inserted into hole  314 .  
      A steering axle assembly  330  is shown generally in  FIG. 24 . The steering axle assembly is advantageously located on the operator side of the unit  50 . The steering axle assembly  330  includes steering axle shafts  334  and  336 , a steering rod  332 , an arm weldment  338 , an axle shaft plate  340 , and steering wheel assemblies  54  and  56 .  
      The unit  50  can be steered from the handle  300 . A lateral movement of the handle  300  will rotate the arm weldment  338 . The rotation of the arm weldment  338  will be translated to the axle shaft plate  340  through the movement of the steering rod  332 . Both the arm welment  338  and the axle shaft plate  340  rotate through the same degree of motion. The steering axle shafts  334  and  336  are likewise both rotated through the same degree of motion, such that the steering wheel assemblies  54  and  56  remain parallel to each other.  
       FIGS. 25-26  illustrate the wagon-style steering and locking feature of the steering axle assembly  330 . The wagon-style steering feature of the present invention is desirable when an operator wishes to cut around curved edges, such as around trees. Other applications exist where the operator may wish to cut in a straight line. In these applications, it is preferable to lock the steering from rotation, so that the operator does not steer the unit  50  off of the straight line. A spring loaded pin  350  is provided to lock the steering so that the unit  50  can only move in a straight line. The spring loaded pin  350  is inserted into hole  352 , which prevents the axle shaft plate  340  from rotating. Removing the spring loaded pin  350  allows the operator to alternate from a steering mode to a straight line mode.  FIG. 25  shows a detailed view of the locking feature, where the spring loaded pin  350  is used to lock the steering axle  330  from rotating.  FIG. 26  shows a detailed view of the locking feature, where the spring loaded pin  350  is removed from the hole  352 , allowing the steering rod  332  to be steered by an operator.  
      The rear axle assembly  400  is shown generally in  FIG. 27 . The rear axle assembly includes a rear axle  402 , a pivot plate  404 , a locking plate  406 , a depth plate  408 , a spring pin  410 , and wheel assemblies  58  and  60 .  
      Wheel assemblies  58  and  60  are rotatably mounted on rear axle  402 . Pivot plate  404  and locking plate  406  are each attached at one end to the rear axle  402 . Pivot plate  404  and locking plate  406  are rotatably attached at the opposite end to frame  500  by bolts  416  and bushings  418 .  
      The depth of the cutting blade for the unit  50  can be conveniently adjusted at the rear axle assembly  400 , as shown in  FIGS. 27 and 28 . In addition, the unit  50  can be converted from an operating position to a transport position by the operator at the handle. A clevis pin  420  fits within the hole  422  on locking plate  406 . The clevis pin  420  can be inserted into one of three operating positions corresponding to one of three holes  423 ,  425 ,  427  on depth plate  408 . The clevis pin  420  is used to select a depth of the cutting blade by selecting one of three operating depth positions. The clevis pin  420  locks the rear axle  402  at one of three different points corresponding to one of three operating depths. Thus, referring to  FIGS. 27, 28  and  30 , an operator can select an operating depth by removing pin  420 , sliding depth plate  408  until the hole  422  aligns with the selected depth hole  423 ,  425 ,  427 , and locking the operating depth into place with clevis pin  420 .  
      Referring to  FIG. 30 , the locking plate  406  includes three holes  433 ,  435 ,  437  which are spatially related to holes  423 ,  425 ,  427 . In addition, these holes  433 ,  435 ,  437  can be selectively aligned with a slot  432  in depth plate  408  depending upon the position of holes  423 ,  425 ,  427  with hole  422  and pin  420 . By moving the depth plate  408  to a specific hole  423 ,  425 ,  427 , two of the holes  433 ,  435 ,  427  are blocked. Thus, if pin  420  is in hole  425 , then the slot  432  will be aligned with hole  435  and holes  433  and  437  are not aligned with the slot  432  as shown in  FIG. 30 . Similarly, if pin  420  is aligned with hole  423 , then the slot  432  will be aligned with hole  433  and holes  435  and  437  are not aligned with the slot  432 . Referring to  FIGS. 29 and 31 , the spring pin  410  engages the slot  432  when the device is in the cutting position. Thus, depending upon the selected hole  423 ,  425 ,  427 , the spring pin  410  will only engage the respective hole  433 ,  435 ,  437  through the slot  432 .  
      Depth plate  408  includes a flat portion that is suitable for attaching a decal  429  as shown in  FIG. 28 . The decal  429  shows the operator the position on the depth plate corresponding to a particular operating depth of the cutting blade.  
      Referring to  FIG. 33 , the handle  300  includes a release lever  324  that allows the operator to alternate between an operating position of the unit, where the cutting blade is at an operating depth, and a transport position, where the cutting blade is above the tires. The unit  50  is shown in  FIG. 33  in a transport position  441  with solid lines and in an operating position  443  with dashed lines. Release lever  324  actuates a spring cable  326 . Referring to  FIG. 27 , the spring cable  326  releases the spring pin  410  from engagement with the locking plate  406  and the depth plate  408 . Once the spring pin  410  is released, the rear axle  402  is free to pivot about axis  451 . Referring to  FIG. 33 , the operator can then exert a downward force on the handle  300  and allow the rear axle  402  to pivot downward. Once the rear axle  402  is in a transport position  441 , the operator can release the release lever  324  and the spring pin  410  will engage the hole  460  in the locking plate  406  as shown in  FIGS. 30 and 32 . When the operator wishes to return the unit to the operating position, the operator pulls the release lever  324  to release spring pin  410  from hole  460 , allows the rear axle  402  to pivot upward, releases the lever  324  and the spring pin  410  engages the slot  432  and the aligned hole  435  as shown in  FIGS. 29 and 31 .  
      Thus, the rear axle assembly  400 , by providing a pivotable rear axle  402 , is capable of operating at different operating depths. Moreover, an operator can conveniently alternate the unit between an operating mode and a transport mode by pulling on release lever  324 , which releases the rear axle  402  from a locked position to allow the rear axle to pivot from either an operating depth or a transport depth.  
      Another embodiment of the ground digging device  50  is shown generally in  FIGS. 36-37 .  FIG. 36  shows the device  50  utilizing the cable layer tool  250  in combination with the bed edger shroud  100 . In this configuration, the device  50  is capable of digging a narrow trench with the cable layer tool  250  and directing the dirt away and to the side of the narrow trench using the bed edger shroud  100 .  FIG. 37  shows a rear view of the device configured with the cable layer tool  250  and the bed edger shroud  100 .  
      The configuration shown in  FIGS. 36-37  is desirable in applications where the operator does not wish to refill the trench. Thus, the device  50 , by using the cable layer tool  250  in combination with the bed edger shroud  100 , is capable of creating a narrow trench that may, for example, be used for installing plastic edging around flower beds.  
      All references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein.  
      The use of the terms “a” and “an” and “the” and similar referents in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms “comprising,” “having,” “including,” and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to,”) unless otherwise noted. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. 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”) provided herein, is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention.  
      Preferred embodiments of this invention are described herein, including the best mode known to the inventors for carrying out the invention. Variations of those preferred embodiments may become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventors expect skilled artisans to employ such variations as appropriate, and the inventors intend for the invention to be practiced otherwise than as specifically described herein. Accordingly, this invention includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context.