Particle coating apparatus

Claim 2

A particle coating apparatus having an upstanding first casing having a generally cylindrical upper section and a downwardly tapered frusto-conical lower section terminating in an air inlet, a nozzle for spraying a coating liquid upwardly into the lower section of said casing, means for supplying coating liquid under pressure to said nozzle, and means for directing air under pressure upwardly through said inlet about said nozzle to suspend and circulate particles in said casing for the coating of said particles as the same are so circulated, wherein the improvement comprises said inlet being open and unobstructed for the free downward flow of particles therethrough when the discharge of air and coating liquid into said casing is discontinued, said means for directing air including a second casing disposed below said first casing and joined to said first casing to define a chamber below said inlet, said second casing having a bottom wall spaced below said inlet for supporting particles falling into said chamber when the flow of pressurized air is discontinued and having a side wall with at least one air entry port above the level of said inlet for the passage of pressurized air through said chamber to the inlet of said first casing.

Claim 3

The apparatus of claim 1 in which said side wall is provided with a plurality of said air entry ports spaced circumferentially about said second casing above said inlet.

Claim 4

The apparatus of claim 1 in which said bottom wall comprises a closure for said chamber and is mounted for movement between open and closed positions.

Claim 5

The apparatus of claim 3 in which said bottom wall is hingedly mounted for movement between said open and closed positions.

Claim 6

The apparatus of claim 3 in which said bottom wall is formed of transparent material.

Claim 7

The apparatus of claim 1 in which Said side wall of said second casing has a lower portion of generally frusto-conical shape spaced outwardly from the frusto-conical lower section of said first casing, said air entry portion being provided in an upper portion of said side wall a substantial distance above said inlet of said first casing.

Claim 8

The apparatus of claim 6 in which said upper portion of said side wall of said second casing is provided with a plurality of said air entry ports spaced circumferentially above said second casing.

Claim 9

The apparatus of claim 1 in which said nozzle extends upwardly through said bottom wall of said second casing and is coaxially disposed relative to said inlet.

Claim 10

The apparatus of claim 1 in which a partition is coaxially mounted in the upper section of said first casing, said partition being open at opposite ends to define an upward inner passage therethrough and an outer annular downward passage between said partition and the inner surface of said first casing''s upper section, said nozzle being mounted in said chamber of said second casing for the spray discharge of coating liquid upwardly towards the open lower end of said partition.

Claim 11

The apparatus of claim 9 in which said partition is frusto-conical in configuration, said inner passage tapering upwardly and said outer annular passage being of downwardly decreasing cross sectional area.

Claim 12

A particle coating apparatus having an upstanding first casing having a generally cylindrical upper section and a downwardly tapered frusto-conical lower section terminating in an air inlet, a nozzle for spraying a coating liquid upwardly into the lower section of said casing, means for supplying coating liquid under pressure to said nozzle, and means for directing air under pressure upwardly through said inlet about said nozzle to suspend and circulate particles in said casing for the coating of said particles as the same are so circulated, wherein the improvement comprises said inlet being open and unobstructed for the free downward flow of particles therethrough when the discharge of air and coating liquid into said casing is discontinued, said means for directing air including a second casing disposed below said first casing and joined to said first casing to define a chamber below said inlet, said second casing having a bottom wall spaced below said inlet for supporting particles falling into said chamber when the flow of pressurized air is discontinued and having a side wall with at least one air entry port above the level of said inlet for the passage of pressurized air through said chamber and to the inlet of said first casing, said second casing also having a tubular inner wall mounted upon said bottom wall, said tubular inner wall being coaxial with said inlet and having an open upper end terminating adjacent said inlet, said tubular inner wall also having an outer diameter substantially smaller than said inlet and defining a vertical passage therethrough, said nozzle being mounted within said passage of said inner wall for the discharge of coating liquid from the open upper end of said passage through said inlet of said first casing.

Claim 13

A particle coating apparatus having an upstanding first casing having a generally cylindrical upper section and a downwardly tapered frusto-conical lower section terminating in an air inlet, a nozzle for spraying a coating liquid upwardly into the lower section of said casing, means for supplying coating liquid under pressure to said nozzle, and means for directing air under pressure upwardly through said inlet about said nozzle to suspend and circulate particles in said casing for the coating of said particles as the same are so circulated, wherein the improvement comprises said inlet being open and unobstructed for the free downward flow of particles therethrough when the discharge of air and coating liquid into said casing is discontinued, said means for directing air including a second casing disposed below said first casing and joined to said first casing to define a chamber below said inlet, said second casing having a bottom wall spaced below said inlet for supporting particles falling into said chamber when the flow of pressurized air is discontinued and having a side wall with at least one air entry port above the level of said inlet for the passage of pressurized air through said chamber and to the inlet of said first casing, said second casing also having a tubular inner wall mounted upon said bottom wall, said tubular inner wall being coaxial with said inlet and having an open upper end terminating adjacent said inlet, said tubular inner wall also having an outer diameter substantially smaller than said inlet and defining a vertical passage therethrough, said nozzle being mounted within said passage of said inner wall for the discharge of coating liquid from the open upper end of said passage through said inlet of said first casing.

Claim 14

The apparatus of claim 11 in which said nozzle is movably mounted within said inner wall for vertical adjustment within and removal from said passage.

Claim 15

The apparatus of claim 11 in which said side wall is provided with a plurality of said air entry ports spaced circumferentially about said second casing above the level of said inlet.

Claim 16

The apparatus of claim 11 in which said bottom wall comprises a closure for said chamber and is mounted for movement between open and closed positions.

Claim 17

The apparatus of claim 14 in which said bottom wall is removably connected to said side wall.

Claim 18

The apparatus of claim 14 in which said bottom wall is formed of transparent material.

Claim 19

The apparatus of claim 11 in which said side wall of said second casing has a lower portion of frusto-conical shape spaced outwardly from the frusto-conical lower section of said first casing, said air entry port being provided in an upper portion of said side wall a substantial distance above said inlet of said first casing.

Claim 20

The apparatus of claim 17 in which said upper portion of said side wall of said second casing is provided with a plurality of said air entry ports spaced circumferentially about said second casing.

Claim 21

The apparatus of claim 10 in which said tubular inner wall extends through and is movably mounted upon said bottom wall for vertical adjustment of said tubular inner wall within said chamber.

Claim 22

The apparatus of claim 19 in which said tubular inner wall is threadedly connected to said bottom wall.

Claim 23

The apparatus of claim 11 in which a partition is coaxially mounted in the upper section of said first casing, said partition being open at its opposite ends to define an upward inner passage therethrough and an outer annular downward passage between said partition and the inner surface of said first casing''s upper section.

Claim 24

The apparatus of claim 21 in which said partition is frusto-conical in configuration, said inner passage tapering upwardly and said outer annular passage being of downwardly decreasing cross sectional area.