Patent ID: 7832243

Claim:
An apparatus for a shot-peening treatment comprising a housing having upper and bottom ends and defining an interior therein, a movable carriage for movably supporting an object to be treated within said interior, at least one shot projection means for projecting shot particles to the object supported on said carriage, a shot circulation system having a collecting level at which said projected and fallen shot particles are collected and returned to said shot projection means to recycle and use the collected shot particles for projection wherein said collecting level is located at a level that is the same as or above that of said bottom end of said housing, said circulation system having at least one cross feeder that is arranged horizontally at said collecting level, for cross feeding collected shot particles, and at least one vertical feeder for upwardly feeding the collected shot particles that are cross fed by said cross feeder, a diversion means that communicates with said vertical feeder at a fixed position above said collecting level and having a closed position and an open position, an aperture of which is adjustable, said diversion means in the closed position diverting all the collected shot particles that arrive at said fixed position by means of said vertical feeder, and in the open position diverting some of the shot particles, based on said adjustable aperture, of the collected shot particles that arrive at said fixed position by said vertical feeder, said diversion means returning the shot particles that have not been diverted to said shot projection means; and at least one removing means provided between said diversion means and said collecting level and disposed below said diversion means such that said shot particles that are diverted by said diversion means pass through therein for removing impurities from these shot particles, said removing means returning the shot particles therefrom to said cross feeder.