Edge Grinding Tool

Abstract

An edge grinding tool is disclosed for dressing the edge of a workpiece using a hand grinder. The tool includes an elongated fence plate with a centrally aligned raised fence that has symmetrical, downward-diverging side surfaces. A grinder holder, attachable to various grinder heads via an optional adapter plate, features a guide plate with wheels that engage the fence's diverging surfaces, enabling smooth, controlled longitudinal movement. A second embodiment features a dual-guide plate system with spring-loaded engagement and a lever mechanism, enabling secure, hands-free operation by locking the grinder holder onto the fence. The tool supports different grinder configurations and includes optional wear and friction strips for added stability. The symmetrical fence design enables the fence plate to be rotated and reused on opposing workpiece edges, resulting in seamless joints. This invention improves precision, repeatability, and ease of use in edge dressing applications, especially for stone or concrete countertops.

We claim: 
     
         1 . An edge grinding tool for grinding an edge of a workpiece with a grinder that includes a head, a body, a perpendicular drive shaft, and a grinding disc attached to the drive shaft, the tool comprising:
 a. an elongated fence plate that includes a longitudinal axis, two parallel outer edges, a top surface, and a raised longitudinally aligned fence formed on the top surface, the fence includes two downward diverging side surfaces, each diverging side surface being the same distance from the adjacent outer edge;   b. a grinder holder including a bracket selectively attached to the head of the grinder, the grinder holder also includes a guide plate, two slide arms, and an adjustment rod, the bracket includes an inside surface and an outside surface, the slide arms and the adjustment arm extending outward from the bracket, the guide plate being configured to slide over freely the slide arms, the adjustment rod being affixed to the guide plate and configured to selectively move and hold the guide plate in a fixed position from the bracket, the guide plate includes two guide wheels spaced apart on the guide plate, each wheel includes a converging outer surface configured to roll against one of the diverging side surfaces on the fence; and,   c. a handle attached to the guide plate.   
     
     
         2 . The edge grinding tool, as recited in  claim 1 , further including the bracket with an outer surface and an adapter plate attached to the outer surface used to connect the head of the grinder to the bracket. 
     
     
         3 . The edge grinding tool, as recited in  claim 1 , further including a shield mounted on the grinder holder that surrounds the body of the grinder. 
     
     
         4 . The edge grinding tool, as recited in  claim 1 , wherein the fence includes a hollow center channel. 
     
     
         5 . The edge grinding tool, as recited in  claim 1 , further including a second guide plate attached to the first guide plate, the second guide plate includes two guide wheels, two slide arms, at least one biasing spring and a lever, the slide arms extend between the first guide plate and the second guide plate, the spring bias the second guide plate inward towards the first guide plate, the lever and the spring are configured so that when the lever is activated or pulled, the second guide plate moves away from the first guide plate enabling both sets of guide wheels to be positioned on opposite sides of the fence, when the lever is released, the first guide plate and the second guide plate slide together so that the guide wheels engage opposite the diverging side surfaces on the fence. 
     
     
         6 . An edge grinding tool for dressing an edge of a workpiece using a grinder, the tool comprising:
 a. an elongated fence plate having a longitudinal axis, two parallel outer edges, a top surface, and a raised fence aligned along the longitudinal axis of the top surface, the fence having a center axis and two downward diverging side surfaces, each diverging side surface being equidistant from its adjacent outer edge;   b. a grinder holder comprising:
 a bracket configured to attach to a head of the grinder; 
 a guide plate slidably connected to the bracket via two slide arms and an adjustment rod, the guide plate including two guide wheels, each guide wheel having a converging outer surface configured to engage one of the diverging side surfaces of the fence; 
 a handle attached to the guide plate for manual operation; and, 
   c. wherein the grinder holder is configured to slide longitudinally along the fence plate while maintaining engagement between the guide wheels and the diverging side surface of the fence.   
     
     
         7 . The edge grinding tool of  claim 6 , wherein the bracket includes an adapter plate configured to interface with various grinder head configurations. 
     
     
         8 . The edge grinding tool of  claim 6 , further comprising a shield mounted on the grinder holder and configured to surround the body of the grinder. 
     
     
         9 . The edge grinding tool of  claim 6 , wherein the fence includes a hollow center channel and a slot formed on the bottom surface of the fence plate, the channel configured to receive clamps for securing the fence plate to the workpiece. 
     
     
         10 . The edge grinding tool of  claim 6 , further comprising a second guide plate attached to the first guide plate, the second guide plate including:
 a. two guide wheels configured to engage the opposite diverging side surface of the fence;   b. two slide arms extending between the first and second guide plates;   c. at least one biasing spring configured to urge the second guide plate toward the first guide plate;   d. a lever configured to move the second guide plate away from the first guide plate to facilitate positioning of the guide wheels; and   e. wherein, upon release of the lever, the guide wheels of both guide plates engage opposite diverging side surfaces of the fence, thereby stabilizing the grinder holder against vertical disengagement.   
     
     
         11 . The edge grinding tool of  claim 6 , wherein the grinder comprises an electric or pneumatic hand grinder having an elongated body, a head at one end of the body, a drive shaft extending perpendicularly from the head, and a grinding disc mounted on the distal end of the drive shaft, the grinder holder being configured to support the grinder such that the grinding disc is oriented vertically and perpendicularly aligned with the edge of the workpiece. 
     
     
         12 . A method for dressing an edge of a workpiece using an edge grinding tool and a hand grinder, comprising the steps of:
 a. positioning an elongated fence plate on a top surface of the workpiece adjacent to the edge on the workpiece to be dressed, the fence plate including a raised longitudinal fence with two downward diverging side surfaces;   b. securing the fence plate to the workpiece using clamps inserted into a center channel formed in the fence;   c. attaching a grinder holder to a head of the hand grinder, the grinder holder including a bracket, a guide plate, two slide arms, and an adjustment rod;   d. positioning the guide plate such that two guide wheels with converging outer surfaces engage one of the diverging side surfaces of the fence;   e. adjusting the position of the guide plate relative to the bracket using the adjustment rod to align a grinding disc of the grinder with the edge of the workpiece;   f. activating the hand grinder and sliding the grinder holder longitudinally along the fence plate to grind the edge of the workpiece.   
     
     
         13 . The method of  claim 12 , further comprising the step of attaching an adapter plate between the grinder head and the bracket to accommodate different grinder configurations. 
     
     
         14 . The method of  claim 12 , further comprising the step of attaching a shield to the grinder holder to surround the body of the hand grinder during operation. 
     
     
         15 . The method of  claim 12 , wherein the guide plate includes a rub plate on its bottom surface to reduce friction with the fence plate during sliding. 
     
     
         16 . The method of  claim 12 , further comprising the steps of:
 a. attaching a second guide plate to the first guide plate via extended slide arms;   b. activating a lever to move the second guide plate away from the first guide plate;   c. positioning a second set of guide wheels on the second guide plate to engage the opposite diverging side surface of the fence;   d. releasing the lever to allow springs to bias the second guide plate toward the first guide plate, thereby securing the grinder holder to the fence.   
     
     
         17 . The method of  claim 12 , wherein the fence plate is rotated 180 degrees and repositioned on a second workpiece to create a matching dressed edge for forming an inconspicuous seam with the first workpiece.