Grinding apparatus with adjustable weighting

Abstract

A grinding apparatus includes a table, a grinding disk assembled on the table, three support plates for supporting workpieces, three weights, and a mechanism to suspend and lower any of the weights over the grinding disk. The three support plates are assembled on the table and located upon the grinding disk. The lifting mechanism includes a drive cylinder, a board member, a connecting member connecting the drive cylinder and the board member, and three fastening members rotatably attached to the board member, for hooking the weight blocks. The drive cylinder drives the board member bringing with the weight blocks to move towards the support plates until the weight blocks loaded on the support plates, to increase a grinding force.

What is claimed is: 
     
         1 . An lifting mechanism for hooking weights of a grinding apparatus, the lifting mechanism comprising:
 a drive cylinder having a cylinder rod;   a board member;   a connecting member connecting the drive cylinder and the board member, and   three fastening members each comprising a shaft, a second latching member for hooking the weights, and a linkage connecting the shaft and the second latching member, the three fastening members being rotatably attached to the board member through the shafts.   
     
     
         2 . The lifting mechanism as claimed in  claim 1 , wherein the board member has a shape of an equilateral triangle and has a retaining ring attached to a substantially middle portion of a surface; the connecting member has a connector, a first latching member, and a connecting chain connecting the connector and the first latching member; the first latching member is interlinked with the retaining ring; the connector is connected to the drive cylinder. 
     
     
         3 . The lifting mechanism as claimed in  claim 2 , wherein the board member has three mounting holes each defined in a corner position of the board member; the shafts extend through the mounting holes, respectively, to be rotatably attached on the board member;
 the second latching members and the connecting member are located at two opposite sides of the board member.   
     
     
         4 . The lifting mechanism as claimed in  claim 1 , wherein each of the second latching members is formed by two arc blocks; each of the two arc blocks has two opposite fastening ends; the two arc blocks of each second latching member are oppositely positioned and detachably assembled by the fastening ends being fixed together by screws. 
     
     
         5 . The lifting mechanism as claimed in  claim 4 , wherein each of the second latching members has a base pressure block attached to; each base pressure block has a retaining ring attached to a substantially middle portion of a surface thereof; the retaining ring is interlinked with one of the second latching members; the weights are attached to the base pressure blocks. 
     
     
         6 . A grinding apparatus comprising:
 a table;   a grinding disk assembled on the table;   three support plates for supporting workpieces, the three support plates assembled on the table and located upon the grinding disk;   weights; and   a lifting mechanism comprising:
 a drive cylinder; 
 a board member; 
 a connecting member connecting the drive cylinder and the board member; and 
 three fastening members rotatably attached to the board member, for hooking the weights; 
 wherein the drive cylinder drives the board member bringing with the weights to move towards the support plates until the weights loaded on the support plates, to increase a grinding force. 
   
     
     
         7 . The grinding apparatus as claimed in  claim 6 , wherein each of the three fastening members comprises a shaft, a latching member for hooking the weights, and a chain connecting the shaft and the latching member, the three fastening members being rotatably attached to the board member through the shafts. 
     
     
         8 . The grinding apparatus as claimed in  claim 7 , wherein each of the latching members is formed by two arc blocks; each of the two arc blocks has two opposite fastening ends; the two arc blocks of each second latching member are oppositely positioned and detachably assembled by the fastening ends fixed together by screws. 
     
     
         9 . The grinding apparatus as claimed in  claim 8 , wherein each of the latching members has a base pressure block attached; each base pressure block has a retaining ring attached to a substantially middle portion of a surface thereof; the retaining ring is interlinked with one of the latching members. 
     
     
         10 . The grinding apparatus as claimed in  claim 9 , wherein the weights are attached to the base pressure blocks. 
     
     
         11 . The grinding apparatus as claimed in  claim 10 , wherein each of the weights has a threaded hole and a locking recess defined on two opposite surfaces, respectively; each of the base pressure blocks has a bolt; each of the support plates has a protrusion protruding from a surface; the weigh blocks are attached to the base pressure blocks by the bolts threadedly secured into the threaded holes; the protrusions are engaged with locking recesses. 
     
     
         12 . The grinding apparatus as claimed in  claim 7 , wherein the table includes a panel and a motor; the panel defines a receiving hole; the grinding disk includes a grinding surface and is received in the receiving hole; the grinding disk is driven by the motor to rotate. 
     
     
         13 . The grinding apparatus as claimed in  claim 12 , further comprising three ledges each including a fixing post fixed to the panel, a retaining board attached to the fixing post and located upon the receiving hole, and two leather wheels mounted to the retaining board; wherein the fixing posts are evenly positioned along a periphery of the receiving hole; a distal end of each retaining board furthest from a corresponding fixing post has an arcuate notch; the two leather wheels of each ledge are located at two ends of the arcuate notch; one of the two leather wheels of each ledge faces the arcuate notch of an adjacent ledge; each support plate is mounted in one of the arcuate notches, with a periphery in contact with the two leather wheels located at two ends of the arcuate notche and in close proximity to the leather wheel of another ledge facing the arcuate notch.