Dust collection device for sanding machine

Abstract

A dust collection device for a sanding machine includes a casing located at the lower end of the upright sanding belt and the casing includes a bottom hole which communicates with the open top of the dust collection part. The dust collection part communicates with an exterior collection area defined within an outer cover. A fan unit an a separation plate are located within the outer cover, so that dust during operation of the sanding belt can be collected into the exterior collection area and brought out via an escape pipe connected to the outer cover. A sanding wheel is located beside the separation plate and a housing is mounted to the sanding wheel. The housing includes a restriction plate so as to guide dust during operation of the sanding wheel into the escape pipe. The sanding belt, the fan unit and the sanding wheel share a common axle.

1 . A sanding machine comprising:
 a base unit including a base and a board mounted on an open top of the base, a space defined in the base and a frame extending upward from the board, a first slot and a second slot defined through the board and communicating with the space, an axle extending through the frame and two ends of the axle protruding from two sides of the frame;   a sanding unit including first and second side panels and a top roller and a lower roller located between the first and second panels, a sanding belt trained on the top roller and the lower roller, a casing accommodating the lower roller and a part of the sanding belt, a bottom hole defined through a bottom of the casing and a guide member located beside the bottom hole, the bottom hole located in alignment with the second slot;   a power unit including a motor located in the space and an active pulley which is driven by an output shaft of the motor, a passive pulley driven by the active pulley by a transmission belt trained on the active and passive pulleys, the axle extending through the passive pulley and a first end of the axle connected to the lower roller and a second end of the axle connected to a fan unit and a sanding wheel, and   a dust collection device including a dust collection part, a hollow hose, an outer cover, the fan unit, a separation plate, the sanding wheel and a housing, the dust collection part located beneath the second slot of the base unit and having an open top which is located in alignment with the second slot, a tube and an outlet located in communicating with the open top of the dust collection part, the hollow hose having a first end connected to the tube;   the outer cover connected to the base unit and the axle extending through an axle hole defined through the outer cover, a shoulder formed on an inside of the outer cover and an air inlet defined through the shoulder of the outer cover, the shoulder located along a periphery of a concaved chamber defined in the inside of the outer cover, a main-air-outlet, a sub-air-outlet and the axle hole located in communicating with the concaved chamber, a second end of the hollow hose connected with the sub-air-outlet in the cuter cover, an escape pipe having a first end engaged with the main-air-outlet;   the fan unit including a central hole and the axle extending through the central hole, the fan unit located in the concaved chamber and the separation plate engaged with the concaved chamber, multiple blades extending radially from a side of the fan unit;   the separation plate including a path, a guide plate, a first hole, a second hole and a suction opening, the path located in communication between the air inlet of the outer cover, the first and second holes and the suction opening, the guide plate located beside the suction opening and a distal end of the guide plate contacting a peripheral wall of the over cover, the air inlet of the outer cover located in communication between the outlet of the dust collection part and the path of the separation plate, and   the sanding wheel mounted to the axle and located between the separation plate and the housing, the housing having a pressing plate extending from an inside thereof so as to define an exterior collection area between the housing, the outer cover and the separation plate, a part of the sanding wheel located within the exterior collection area.   
   
   
       2 . The sanding machine as claimed in  claim 1 , wherein a rear cover is connected between a top of the base unit and a lower end of the casing of the sanding unit, the rear cover includes an opening which is located in alignment with the bottom hole of the casing and the second slot of the base unit. 
   
   
       3 . The sanding machine as claimed in  claim 1 , wherein the casing includes a first part and a second part, the bottom hole is defined through the first part and the guide member is located on the first part. 
   
   
       4 . The sanding machine as claimed in  claim 1 , wherein the outer cover includes multiple connection tubes and bolts extend through the connection tubes and connects the outer cover to the base unit. 
   
   
       5 . The sanding machine as claimed in  claim 1 , wherein the first hole of the separation plate includes two tapered insides and is larger than the second hole, a distal end of the first hole is located at the air inlet. 
   
   
       6 . The sanding machine as claimed in  claim 1 , wherein the first hole of the separation plate includes two tapered insides and is larger than a cross sectional area at the conjunction between the first hole and the path, a distal end of the first hole is located at the air inlet. 
   
   
       7 . The sanding machine as claimed in  claim 1 , wherein the first hole of the separation plate includes two tapered insides and is larger than the suction opening, a distal end of the first hole is located at the air inlet. 
   
   
       8 . The sanding machine as claimed in  claim 1 , wherein the separation plate includes a rib extending from a side thereof and being shaped corresponding to a shape of the concaved chamber, the rib, the path and the guide plate are located on different planes on the separation plate, a plurality of through holes are defined through the separation plate and bolts extend through the through holes and connect the separation plate to the shoulder of the outer cover, the rib encloses the concaved chamber. 
   
   
       9 . The sanding machine as claimed in  claim 2 , wherein the guide member has one end protruding beyond a surface of the first part. 
   
   
       10 . The sanding machine as claimed in  claim 1 , wherein the housing includes a curved restriction plate extending from a side facing the sanding wheel.