Global Patent Index - EP 0933142 A3

EP 0933142 A3 20000719 - Method for the pneumatic classification of toner

Title (en)

Method for the pneumatic classification of toner

Title (de)

Verfahren zur Windsichtung von Toner

Title (fr)

Procédé pour le tri pneumatique de toner

Publication

EP 0933142 A3 20000719 (DE)

Application

EP 99100551 A 19990113

Priority

DE 19803107 A 19980128

Abstract (en)

[origin: EP0933142A2] A rotary disc (16) distributes toner evenly over the classification rotor (8) circumference. The toner descends under gravity, being guided through the classification zone (21). A spiral controls toner residence time distribution from top to bottom of the classification zone. Toner is introduced quickly in the homogenous state at the top and resides for a longer interval in the central part of the classification zone. At the bottom it is carried away continuously. Classification air driven past the outer edge of the rotor flows at a mean velocity of 3-7 m/s. The ratio of mass flowrate of toner to volumetric airflow is held at 0.05-0.3 kg/m<3>, based on product weight. Residence time is controlled by a coaxial spiral (29) around the classification rotor. This occupies only part of the radial extent of the classification zone. Over its length, the pitch of the spiral varies. Toner mass flowrate to classification air volumetric flowrate is preferably 0.1 kg/m<3>. Mean velocity of classification air is 5 m/s.

IPC 1-7

B07B 7/083; G03G 9/08

IPC 8 full level

B07B 7/083 (2006.01); B07B 11/06 (2006.01); G03G 9/08 (2006.01); G03G 9/087 (2006.01)

CPC (source: EP)

B07B 7/083 (2013.01); B07B 11/06 (2013.01); G03G 9/0817 (2013.01)

Citation (search report)

Designated contracting state (EPC)

AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE

DOCDB simple family (publication)

EP 0933142 A2 19990804; EP 0933142 A3 20000719; EP 0933142 B1 20020605; AT E218399 T1 20020615; DE 19803107 A1 19990729; DE 59901580 D1 20020711; JP H11288133 A 19991019

DOCDB simple family (application)

EP 99100551 A 19990113; AT 99100551 T 19990113; DE 19803107 A 19980128; DE 59901580 T 19990113; JP 1995299 A 19990128