×

Pneumatic powder metering apparatus with improved powder throttling mechanism

  • US 4,569,161 A
  • Filed: 11/03/1983
  • Issued: 02/11/1986
  • Est. Priority Date: 11/03/1983
  • Status: Expired due to Term
First Claim
Patent Images

1. Powder metering apparatus for metering powder to a nozzle of a conventional handpiece used in an abrasive jet machining device and the like, said metering apparatus being substantially cylindrical and comprisinga hopper for containing said powder,a powder dispensing member mounted to said hopper in powder receiving relationship thereto, said dispensing member having an axially disposed powder feed orifice at a lowermost portion,a needle valve assembly support plate mounted to an underside of said dispensing member, said support plate having a central bore therethrough, said central bore receiving said powder feed orifice at an upper portion thereof and a throttling needle at a lower portion thereof to form a spaced gap therebetween, said central bore forming a chamber embracing said spaced gap, said throttling needle flattened at its tip or uppermost portion to provide a diameter thereat larger than opening of said powder feed orifice, said throttling needle including an exteriorly threaded portion below its flattened tip and a non-circular head at its lowermost portion,means disposed in said needle valve assembly support plate for directing pressurized air at said gap to entrain powder thereat to provide an air-powder mixture, said powder feed orifice discontinuing powder flow therefrom upon absence of air flow from said means disposed in said needle valve assembly support plate, other means disposed in said support plate for receiving said air-powder mixture for transmission to said nozzle,an interiorly threaded adjusting collar for receiving said exteriorly threaded throttling needle therein,a base plate secured to an underside of said needle valve assembly support plate, said base plate having an opening for matingly receiving said non-circular head of said throttling needle,means for rotating said adjusting collar while said throttling needle is restrained from rotational movement by means of engagement of said non-circular head in said opening, said opening permitting vertical movement of said non-circular head therein and hence, vertical movement of said throttling needle in said central bore, said vertical movement of said throttling needle changing size of said gap for additionally controlling metering of said powder from said powder feed orifice.

View all claims
  • 3 Assignments
Timeline View
Assignment View
    ×
    ×