Patent ID: 8753432

Claim:
Apparatus providing resin material to resin material processing equipment, comprising: a. a housing having a resin material intake, a granular material outlet, the outlet being located for downward, gravity flow of resin material towards the processing equipment, and a suction inlet for drawing vacuum within the housing to convey resin material into the housing under vacuum; b. a dust filter connected to the housing and positioned therewithin between the resin intake and the suction inlet so that air from the resin intake cannot reach the suction inlet without passing through the dust filter; c. apparatus connected to the housing for delivering an air blast to the housing interior for air flow through the dust filter in a direction opposite the direction air is drawn through the filter towards the suction inlet, comprising: i. a shell having an a first aperture communicating with the housing interior and a second aperture for introduction of pressurized air into the shell; ii. a closure member movable slideably within the shell to close the first aperture at one extremity of member travel; iii. a seal between the closure member and the shell interior, permitting air flow between the shell interior and the closure member towards the first aperture, but blocking air flow between the shell interior and the closure member towards the second aperture.