Trenching Assembly

Abstract

An apparatus for cutting a trench is formed from a housing and a cutting assembly at least partially positioned within the housing. The cutting assembly has a cutting wheel and a plurality of teeth extending from the periphery of the cutting wheel. The cutting wheel features a plurality of layers of cylindrical profile in which at least two of the layers have profiles with different diametrical dimensions. At least some of the teeth are positioned on different layers. A trench is formed by placing the apparatus on a surface of the ground and pushing or pulling the apparatus while the cutting assembly is rotated. In one configuration, at least one layer having a profile of larger diametrical dimension is situated between a pair of layers having profiles of smaller diametrical dimension. In such configuration, the apparatus cuts a t-shaped trench.

What is claimed is: 
     
         1 . An apparatus, comprising:
 a housing having a ground-engaging base, in which an opening is formed in the base; and   a cutting assembly at least partially positioned within the housing and comprising:
 a cutting wheel having a plurality of layers of cylindrical profile in which at least two of the layers have profiles with different diametrical dimensions; and 
 a plurality of teeth extending from the periphery of the cutting wheel in which at least some of the teeth are positioned on different layers. 
   
     
     
         2 . The apparatus of  claim 1  in which the layers are arranged such that a layer having a profile of larger diametrical dimension is situated intermediate a pair of layers having profiles of smaller diametrical dimension. 
     
     
         3 . The apparatus of  claim 1  in which the cutting wheel has a pair of opposed ends and in which the plurality of layers further comprise:
 a pair of outer layers in which one outer layer is situated adjacent each end; and 
 an inner layer situated intermediate the outer layers. 
 
     
     
         4 . The apparatus of  claim 3  in which the profile of the inner layer has a larger diametrical dimension than the profile of either outer layer. 
     
     
         5 . The apparatus of  claim 1  in which the teeth extend through the opening formed in the base. 
     
     
         6 . The apparatus of  claim 1  in which at least two layers are traversed by respective cross planes extending in parallel relationship, each of the at least two layers supporting at least two teeth that extend at different angles relative to that layer's cross plane. 
     
     
         7 . A system, comprising:
 the apparatus of  claim 1 ; and   a t-shaped trench formed in the ground and within which the cutting wheel is partially positioned.   
     
     
         8 . An apparatus, comprising:
 a housing having a pair of first and second spaced side walls, each side wall having an outer surface and an inner surface, the first side wall having an outer slot opening formed in the outer surface, an inner slot opening formed in the inner surface, and a slot extending through the first side wall between the outer slot opening and the inner slot opening;   a plate adjustably positioned over the outer slot opening, the plate characterized by a raised position in which the plate uncovers a portion of the outer slot opening, and a lowered position in which the plate covers the portion of the outer slot opening;   a motor assembly supported on the plate;   a cutting assembly connected to the motor assembly and at least partially positioned within the housing; and   a retractable cover in which the cover extends over at least a portion of the outer slot opening when the plate is in the raised position.   
     
     
         9 . The apparatus of  claim 8 , the cutting assembly, further comprising:
 a cutting wheel having a plurality of layers of cylindrical profile in which at least two of the layers have profiles with different diametrical dimensions; and   a plurality of teeth extending from the periphery of the cutting wheel in which at least some of the teeth are positioned on different layers.   
     
     
         10 . The apparatus of  claim 8  in which the housing has a lower surface having an opening and in which the cutting assembly extends through the lower surface opening. 
     
     
         11 . The apparatus of  claim 8  in which the cover is flexible. 
     
     
         12 . The apparatus of  claim 8 , further comprising:
 a device configured to move the plate relative to the housing and to maintain the plate in a fixed position at any selected point on its path of travel.   
     
     
         13 . The apparatus of  claim 8 , further comprising:
 a vacuum system having a hose; and   a port formed in the housing in which the hose connects the housing to the vacuum system via the port.   
     
     
         14 . The apparatus of  claim 10  in which the lower surface comprises:
 a skid plate. 
 
     
     
         15 . An apparatus, comprising:
 a housing having a pair of opposed ends, each end comprising:
 a coupler in which the couplers are formed as mirror images with respect to a plane that extends through the housing; and 
   a cutting assembly at least partially positioned within the housing.   
     
     
         16 . The apparatus of  claim 15  in which the plane traverses the cutting assembly. 
     
     
         17 . The apparatus of  claim 15 , the cutting assembly, further comprising:
 a cutting wheel having a plurality of layers of cylindrical profile in which at least two of the layers have profiles with different diametrical dimensions; and   a plurality of teeth extending from the periphery of the cutting wheel in which at least some of the teeth are positioned on different layers.   
     
     
         18 . The apparatus of  claim 15 , further comprising:
 a work machine in which the work machine is attachable to either coupler.