Apparatus for building tobacco rods in cigarette making machines

Apparatus for building at least one rod-like filler containing at least one constituent of a mixture of smokable particulate materials and being pneumatically delivered to at least one foraminous conveyor, comprising:

• means for supplying the at least one constituent to the foraminous conveyor, including at least one guide having a surface defining a path for advancement of the at least one constituent to the foraminous conveyor;
• a metering device arranged to supply the at least one constituent into said path;
• and
• a sifter arranged to supply the at least one constituent and air toward said metering device,
• wherein said sifter includes an at least substantially upright zig-zag sifter having a plurality of stages including a lower-most stage, a pneumatic follow-up sifter beneath said lowermost stage, and a rotary picker roller disposed opposite said follow-up sifter and arranged to break up coherent accumulations—if any—of the mixture of smokable particulate materials in said zig-zag sifter.

Apparatus for building at least one rod-like filler containing at least one constituent of a mixture of smokable particulate materials and being pneumatically delivered to at least one foraminous conveyor, comprising:

• means for supplying the at least one constituent to the foraminous conveyor, including at least one guide having a surface defining a path for advancement of the at least one constituent to the foraminous conveyor;
• a metering device arranged to supply the at least one constituent into said path;
• and
• a sifter arranged to supply the at least one constituent and air toward said metering device,
• wherein said metering device is arranged to supply the at least one constituent with a surplus which is removed at said at least one foraminous conveyor, said sifter including an at least substantially upright zig-zag sifter having a plurality of stages including an uppermost stage, and further comprising a pneumatic return conduit for delivery of the removed surplus into the sifter at said uppermost stage thereof.

Apparatus for building at least one rod-like filler containing at least one constituent of a mixture of smokable particulate materials and being pneumatically delivered to at least one foraminous conveyor, comprising:

• means for supplying the at least one constituent to the foraminous conveyor, including at least one guide having a surface defining a path for advancement of the at least one constituent to the foraminous conveyor;
• a metering device arranged to supply the at least one constituent into said path;
• and
• a sifter arranged to supply the at least one constituent and air toward said metering device,
• wherein said sifter is an at last substantially upright pneumatic zig-zag sifter having a plurality of stages disposed at different levels and including a substantially median stage, said zig-zag sifter further having an inlet and further comprising a duct having an inlet and an outlet, said inlet communicating with said median stage and said duct being arranged to direct the mixture downwardly, and further comprising a reservoir for the mixture and a rotary carded feeding roller arranged to supply mixture from said reservoir into the inlet of said duct.

Apparatus for building at least one rod-like filler containing at least one constituent of a mixture of smokable particulate materials and being pneumatically delivered to at least one foraminous conveyor, comprising:

• means for supplying the at least one constituent to the foraminous conveyor, including at least one guide having a surface defining a path for advancement of the at least one constituent to the foraminous conveyor;
• a metering device arranged to supply the at least one constituent into said path;
• a sifter arranged to supply the at least one constituent and air toward said metering device;
• and
• an air circulating system including a transverse air stream generating rotary blower, said sifter constituting a multistage zig-zag sifter forming an integral part of said system and having an uppermost stage and a lowermost stage, and further comprising means for regulating the rotational speed of said blower in dependency upon changes of a pressure differential existing between air in the uppermost and lowermost stages of said zig-zag sifter.

Apparatus for building at least one rod-like filler containing at least one constituent of a mixture of smokable particulate materials and being pneumatically delivered to at least one foraminous conveyor, comprising:

• means for supplying the at least one constituent to the foraminous conveyor, including at least one guide having a surface defining a path for advancement of the at least one constituent to the foraminous conveyor;
• a metering device arranged to supply the at least one constituent into said path;
• a sifter arranged to supply the at least one constituent and air toward said metering device;
• and
• means for monitoring the quantity of the at least one constituent in said metering device, a magazine for the mixture, and means for feeding the mixture from said magazine into said sifter at a rate depending upon the quantity of the at least one constituent in said metering device.

Apparatus for building at least one rod-like filler containing at least one constituent of a mixture of smokable particulate materials and being pneumatically delivered to at least one foraminous conveyor, comprising:

• means for supplying the at least one constituent to the foraminous conveyor, including at least one guide having a surface defining a path for advancement of the at least one constituent to the foraminous conveyor;
• a metering device arranged to supply the at least one constituent into said path;
• and
• a sifter arranged to supply the at least one constituent and air toward said metering device,
• wherein said sifter includes an at least substantially upright zig-zag sifter and further comprising a magazine for a supply of the mixture and an elevator conveyor arranged to supply mixture from said magazine into said zig-zag sifter.