Powder feed cylinder assemblies and powder feeders

A powder feed cylinder assembly, comprising:

• a cylinder having a first end, a second end, a main passage, a first feed channel, and a second feed channel, the main passage extending axially through the cylinder, the first feed channel formed radially through the cylinder at a first axial location between the first and the second ends and in communication with the main passage, and the second feed channel formed radially through the cylinder at a second axial location between the first and the second ends and in communication with the main passage;
• a bit extending through the cylinder and having a first end, a second end, and an outer surface including a helical channel formed on the outer surface;
• a center bushing disposed in the main passage between the first and second axial locations, the center bushing having a first axially-extending passage through which a first portion of the bit extends;
• a first powder retention assembly disposed in the main passage on a first side of the center bushing between the center bushing and the first end of the cylinder, the first powder retention assembly including:
• a first end bushing disposed in the main passage and having a second axially-extending passage through which a second portion of the bit extends, the first end bushing disposed on a first side of and spaced apart from the center bushing,
• a first fitting disposed in the main passage between the first end of the bit and the first end bushing, the first fitting including a first opening through which a third portion of the bit extends, and
• a slinger disposed in the main passage between the first end of the bit and the first end bushing;
• and
• a second powder retention assembly disposed in the main passage on a second side of the center bushing between the center bushing and the second end of the cylinder, the second powder retention assembly including:
• a second end bushing disposed in the main passage and having a third axially-extending passage through which a fourth portion of the bit extends, the second end bushing disposed on a second side of and spaced apart from the center bushing, and
• a second fitting disposed in the main passage between the second end of the bit and the second end bushing, the second fitting including a second opening through which a fifth portion of the bit extends.

A powder feeder, comprising:

• a hopper having an outlet;
• a powder feed assembly coupled to the hopper, the powder feed assembly including:
• a housing assembly including:
• a connector plate coupled to the hopper, and
• a housing block coupled to the connector plate;
• and
• a powder feed cylinder assembly disposed between the connector plate and the housing block, the powder feed cylinder assembly including:
• a cylinder having a first end, a second end, a first opening, and a second opening, the first opening formed at a first axial location between the first and the second ends and in communication with the outlet of the hopper, and the second opening formed at a second axial location between the first and the second ends,
• a bit extending through the cylinder and having a first end, a second end, and an outer surface including a helical channel formed on the outer surface,
• a center bushing disposed in the cylinder between the first and second axial locations, the center bushing having a first axially-extending passage receiving a first portion of the bit, the first axially-extending passage defined by an inner surface spaced apart from the outer surface of the bit to form a gap,
• a first end bushing disposed in the cylinder and having a second axially-extending passage receiving a second portion of the bit, the first end bushing disposed on a first side of and spaced apart from the center bushing, and
• a second end bushing disposed in the cylinder and having a third axially-extending passage receiving a third portion of the bit, the second end bushing disposed on a second side of and spaced apart from the center bushing.