Concrete dowel placement system and method of making the same

Abstract

A concrete dowel placement system and methods for making the same. The system allows for accurate and easy substantially-parallel or parallel placement of slip dowels within sections of concrete so that adjacent sections of concrete may be allowed to undergo thermal expansion and contraction while remaining in a common plane without cracking or faulting. The system includes a coupler and a sheath. The sheath is configured to be slidably extensible over the coupler and may be held to the coupler by friction. Additionally, a method of constructing the concrete dowel placement system includes extruding material to form two tubes of different sizes. The tubes are then attached to each other, then material is extruded to form a sheath. Alternatively, construction may include extruding material to form a tube, then removing some of the material from the tube in order to form a coupler.

1 - 10 . (canceled) 
     
     
         11 . A concrete dowel placement system comprising:
 a coupler comprising:
 an extruded first tubular element comprising:
 an inner sleeve disposed about a central axis to define an aperture; and 
 an outer body disposed radially outward of the inner sleeve; 
 
 an extruded second tubular element comprising:
 an inner sleeve disposed about a central axis to define an aperture; and 
 an outer body disposed radially outward of the inner sleeve; 
 
 the second tubular element having a dimensional size different from a dimensional size of the first tubular element and an end portion of the outer element of the second tubular element being attached to an end portion of the outer element of the first tubular element; and 
   an elongated, extruded, tubular, dowel-receiving sheath having at least one interior opening extending along the entire length of the sheath and being slidably extensible over the coupler to frictionally engage one of the first tubular element and the second tubular element.   
     
     
         12 . (canceled) 
     
     
         13 . The system of  claim 11 , further comprising an end cap attachable to an end portion of the sheath to completely cover the at least one opening at an end of the sheath. 
     
     
         14 . The system of  claim 11 , wherein the sheath further comprises at least one linear rib protrusion or linear groove along a longitudinal axis of the sheath on an outer surface of the sheath. 
     
     
         15 . The system of  claim 11 , wherein the sheath further comprises at least one helical element on an outer surface of the sheath. 
     
     
         16 - 20 . (canceled) 
     
     
         21 . The system of  claim 11 , wherein the first and second tubular elements are separately extruded and the end portion of the outer element of the second tubular element is subsequently attached to the end portion of the outer element of the first tubular element. 
     
     
         22 . The system of  claim 11 , further comprising an additional elongated, extruded, tubular, dowel-receiving sheath having at least one interior opening extending along the entire length of the sheath and being slidably extensible over the coupler to frictionally engage the other of the first tubular element and the second tubular element. 
     
     
         23 . A concrete dowel placement system comprising:
 a coupler comprising:
 a tubular element having an unchanging or continuously changing cross section allowing formation of the tubular element by extrusion, the tubular element comprising:
 an inner sleeve disposed about a central axis to define an aperture; and 
 an outer body disposed radially outward of the inner sleeve; and 
 
   an elongated, tubular, dowel-receiving sheath having an unchanging or continuously changing cross section allowing formation of the sheath by extrusion, the sheath having at least one interior opening extending along the entire length of the sheath and being slidably extensible over the coupler to frictionally engage the tubular element.   
     
     
         24 . The system of  claim 23 , further comprising an end cap attachable to an end portion of the sheath to cover the at least one opening at an end of the sheath. 
     
     
         25 . The system of  claim 23 , wherein the sheath further comprises at least one linear rib protrusion or linear groove extending along a longitudinal axis of the sheath on an outer surface of the sheath. 
     
     
         26 . The system of  claim 23 , wherein the sheath further comprises at least one helical element extending on an outer surface of the sheath. 
     
     
         27 . A concrete dowel placement system comprising:
 a coupler comprising:
 a tubular element having an unchanging or continuously changing cross section allowing formation of the tubular element by extrusion, the tubular element comprising:
 an inner sleeve disposed about a central axis to define an aperture; and 
 a plurality of splines extending radially outward from the inner sleeve to provide an outer engagement surface; and 
 
   an elongated, tubular, dowel-receiving sheath having at least one interior opening extending along the entire length of the sheath and being slidably extensible over the coupler to frictionally engage the outer engagement surface of the coupler.   
     
     
         28 . The system of  claim 27 , wherein the sheath has an unchanging or continuously changing cross section allowing formation of the sheath by extrusion. 
     
     
         29 . The system of  claim 27 , further comprising an end cap attachable to an end portion of the sheath to cover the at least one opening at an end of the sheath. 
     
     
         30 . The system of  claim 27 , wherein the sheath further comprises at least one linear rib protrusion or linear groove extending along a longitudinal axis of the sheath on an outer surface of the sheath. 
     
     
         31 . The system of  claim 27 , wherein the sheath further comprises at least one helical element extending on an outer surface of the sheath.