Method and apparatus for blasting

Claim 1

A method for blasting, which comprises: disposing (1) an endless belt supported in position by two rollers, (2) a contact roller held in contact against said endless belt at a point separated from the zones in which said endless belt comes into contact with said supporting rollers, (3) an abrasive feeder the opening of which is directed toward the point at which said contact roller and said endless belt reach the starting point of contact when said endless belt is put to motion and (4) an object subjected to blasting treatment which is positioned at a distance from the point at which the contact between said contact roller and said endless belt terminates and causing said endless belt to revolve and said contact roller to rotate at substantially the same high rate of speed and in opposite directions, and at the same time allowing the abrasive feeder to discharge the abrasive for thereby delivering said abrasive between the mutually approaching surfaces of said contact roller and said endless belt, whereby the abrasive is projected at a high rate of speed by means of the momentum of the motion of said roller and said endless belt so as to impinge upon the object being treated.

Claim 2

A method for blasting, which comprises: disposing (1) an endless belt supported in position by two rollers, (2) a contact roller held in contact against said endless belt at a point separated from the zones in which said endless belt comes into contact with said supporting rollers, (3) an abrasive feeder the opening of which is directed toward the point at which said contact roller and said endless belt reach the starting point of contact when said endless belt is put to motion and (4) an object subjected to blasting treatment which is positioned at a distance from the point at which the contact between said contact roller and said endless belt terminates and causing said endless belt to revolve and said contact roller to rotate at substantially the same high rate of speed and in opposite directions, and at the same time allowing the abrasive feeder to discharge the abrasive for thereby delivering said abrasive between the mutually approaching surfaces of said contact roller and said endless belt, whereby the abrasive is projected at a high rate of speed by means of the momentum of the motion of said roller and said endless belt so as to impinge upon the object being treated.

Claim 3

An apparatus for blasting, which comprises: 1. a device for projecting an abrasive, consisting of (a) a roller, (b) an adjusting roller positioned at a distance from said roller and movable so as to permit adjustment of said distance from said roller, (c) an endless belt held in position by said roller (a) and said adjusting roller (b), (d) a contact roller held in contact against said endless belt (c) at a point separated from the zones in which said endless belt comes into contact with said rollers (a) and (b) and movable so as to permit adjustment of the strength with which the contact roller is kept in contact with the endless belt and (e) a feeder having an opening directed toward the point of contact between said endless belt and said contact roller and disposed so as to permit the abrasive to be fed in the direction of the travel of the endless belt, 2. a means for accommodating the object subjected to blasting treatment, which means is separated by fixed distances from said roller and said contact roller and disposed opposite from said feeder with reference to said roller and said contact roller, 3. a blasting chamber containing therein said device for projecting the abrasive and said means for accommodating the object, 4. a hooper disposed above said feeder and provided with a means for delivering into the feeder its contents, 5. a discharge outlet formed at the bottom of the blasting chamber and adapted to discharge the used abrasive from within the blasting chamber, 6. a means adapted to form a path leading from said discharge outlet to said hopper for thereby returning to said hopper what has been discharged from said discharge outlet and 7. a driving means for imparting high-speed rotations to the rollers and said endless belt, said rollers and said belt being driven at substantially the same rate of speed and in opposite directions.

Claim 4

An apparatus for blasting, which comprises: 1. a device for projecting an abrasive, consisting of (a) a roller, (b) an adjusting roller positioned at a distance from said roller and movable so as to permit adjustment of said distance from said roller, (c) an endless belt held in position by said roller (a) and said adjusting roller (b), (d) a contact roller held in contact against said endless belt (c) at a point separated from the zones in which said endless belt comes into contact with said rollers (a) and (b) and movable so as to permit adjustment of the strength with which the contact roller is kept in contact with the endless belt and (e) a feeder having an opening directed toward the point of contact between said endless belt and said contact roller and disposed so as to permit the abrasive to be fed in the direction of the travel of the endless belt, 2. a means for accommodating the object subjected to blasting treatment, which means is separated by fixed distances from said roller and said contact roller and disposed opposite from said feeder with reference to said roller and said contact roller, 3. a blasting chamber containing therein said device for projecting the abrasive and said means for accommodating the object, 4. a hooper disposed above said feeder and provided with a means for delivering into the feeder its contents, 5. a discharge outlet formed at the bottom of the blasting chamber and adapted to discharge the used abrasive from within the blasting chamber, 6. a means adapted to form a path leading from said discharge outlet to said hopper for thereby returning to said hopper what has been discharged from said discharge outlet and 7. a driving means for imparting high-speed rotations to the rollers and said endless belt, said rollers and said belt being driven at substantially the same rate of speed and in opposite directions.