Disc sander

Abstract

A disc sander includes a rotary disc on which an abrasive paper is adhered for grinding workpieces. The abrasive paper is replaced by dismantling and replacing a new rotary disc adhered with a new abrasive paper without the need of peeling off the to-be-replaced abrasive paper. The disc sander includes a guard, which is moveable between a sheltered position where the guard covers around a periphery of the rotary disc to ensure the user's safety, and an unsheltered position where the rotary disc is not covered by the guard and accessible by the user, such that the user can conveniently dismantle the rotary disc from an output shaft of a motor and then install a new rotary disc, on which an abrasive paper having required roughness is adhered, on the output shaft.

What is claimed is: 
     
         1 . A disc sander, comprising:
 a base having a bottom portion and a support portion uprightly disposed on the bottom portion;   a worktable disposed on the support portion;   a motor disposed on the support portion and provided with an output shaft adjacent to a lateral side of the worktable;   a rotary disc between the worktable and the motor, the rotary disc being fixedly mounted to the output shaft and provided with a lateral disc surface adjacent to the lateral side of the worktable in a way that an upper half of the rotary disc is located above an imaginary plane at which the worktable is situated;   a guard disposed on the support portion and extending along a periphery of the rotary disc and covering an outside of the periphery of the rotary disc;   wherein the guard is moveably coupled to the support portion and moveable between a sheltered position and an unsheltered position; when the guard is located at the sheltered position, the guard covers an outside of a periphery of the upper half of the rotary disc, such that the guard forms a safety shelter around the periphery of the upper half of the rotary disc; when the guard is located at the unsheltered position, the guard does not cover the outside of the periphery of the upper half of the rotary disc, such that the periphery of the rotary disc is accessible without being sheltered.   
     
     
         2 . The disc sander as claimed in  claim 1 , wherein the guard includes a first end pivotally coupled to the support portion, such that the guard is reciprocatingly swivelable about a pivot shaft provided between the guard and the support portion between the sheltered position and the unsheltered position. 
     
     
         3 . The disc sander as claimed in  claim 2 , wherein the pivot shaft extends in a direction orthogonal to an imaginary plane at which the rotary disc is situated in a way that the direction does not pass through the rotary disc. 
     
     
         4 . The disc sander as claimed in  claim 2 , further comprising a coupling unit disposed with the guard and the support portion for coupling the guard to the support portion. 
     
     
         5 . The disc sander as claimed in  claim 4 , wherein the coupling unit comprises a first coupling member disposed on a second end of the guard, a second coupling member disposed on the support portion; when the guard is located at the sheltered position, the first coupling member and the second coupling member are engaged with each other; when the guard is located at the unsheltered position, the first coupling member is departed away from the second coupling member. 
     
     
         6 . The disc sander as claimed in  claim 5 , wherein the second coupling member is a quick-release handle lever having a shaft, and the first coupling member is a protrusion having a notch; when the guard is located at the sheltered position, the shaft of the quick-release handle lever is engaged with the notch of the protrusion. 
     
     
         7 . The disc sander as claimed in  claim 1 , wherein the guard comprises an end plate located outside the periphery of the rotary disc, and a front plate located outside the lateral disc surface of the rotary disc and fixed to the end plate. 
     
     
         8 . The disc sander as claimed in  claim 1 , wherein the support portion comprises two lateral members spaced from each other, and a mount pivotally connected between the two lateral members and swivelable between an upright position and an inclined position. 
     
     
         9 . The disc sander as claimed in  claim 8 , wherein the worktable is mounted on the two lateral members, and the motor is mounted on the mount. 
     
     
         10 . The disc sander as claimed in  claim 8 , wherein the support portion comprises an elongated rod having an end coupled to one of the two lateral members, and the other end slidably inserted through the mount; a compression spring is sleeved onto the elongated rod; the compression spring has an end abutted against the mount for imparting a spring force on the mount to maintain the mount at the upright position.