Apparatus for separating and recovering solid developer particles transported by a gaseous flow

Claim 1

An apparatus for separating and recovering solid developer particles transported by a gaseous flow comprising: a separation chamber (40) having an axis of revolution (45) disposed substantially vertically, the chamber having in its upper portion an admission conduit (43) for admitting gas into the chamber (40) and arranged so as to create a turbulent flow for a gaseous flow, laden with solid developer particles, and an escape conduit (44) disposed axially of the chamber to enable the evacuation of the gaseous flow, from which the particles have been removed, the chamber further including, in its lower portion, an outlet opening (46) communicating with a discharge conduit (47) having a section smaller than that of the separation chamber, said conduit being closed at its lower end by a movable shutter (49) to provide a box for recovery of particles, the chamber being arranged such that the developer particles, after being separated from the gaseous flow int he chamber, are urged by gravity toward the discharge conduit and into the box; and a helical device (52) disposed in the discharge conduit (47) and in proximity with the outlet opening (46), the helical device having a surface the helical edge (53) of which is in contact with the internal wall of the discharge conduit, and the inclination of which with respect tot he horizontal has a value between 3° and 10° and is oriented in the same direction as that of the helical path of the solid particles to be transported by the gaseous flow, to prevent particles arriving in the recovery box from being re-aspirated by the rising gaseous flow which circulates above said helical device and finally escapes via the escape conduit.

Claim 2

An apparatus for separating and recovering solid developer particles transported by a gaseous flow comprising: a separation chamber (40) having an axis of revolution (45) disposed substantially vertically, the chamber having in its upper portion an admission conduit (43) for admitting gas into the chamber (40) and arranged so as to create a turbulent flow for a gaseous flow, laden with solid developer particles, and an escape conduit (44) disposed axially of the chamber to enable the evacuation of the gaseous flow, from which the particles have been removed, the chamber further including, in its lower portion, an outlet opening (46) communicating with a discharge conduit (47) having a section smaller than that of the separation chamber, said conduit being closed at its lower end by a movable shutter (49) to provide a box for recovery of particles, the chamber being arranged such that the developer particles, after being separated from the gaseous flow int he chamber, are urged by gravity toward the discharge conduit and into the box; and a helical device (52) disposed in the discharge conduit (47) and in proximity with the outlet opening (46), the helical device having a surface the helical edge (53) of which is in contact with the internal wall of the discharge conduit, and the inclination of which with respect tot he horizontal has a value between 3° and 10° and is oriented in the same direction as that of the helical path of the solid particles to be transported by the gaseous flow, to prevent particles arriving in the recovery box from being re-aspirated by the rising gaseous flow which circulates above said helical device and finally escapes via the escape conduit.

Claim 20

An apparatus for separating and recovering solid developer particles transported by a gaseous flow, comprising: a separation chamber (40) having an axis of revolution (45) disposed substantially vertically, the chamber having in its upper portion an admission conduit (43) for admitting gas into the chamber (40) and arranged so as to create a turbulent flow for a gaseous flow, laden with solid developer particles, and an escape conduit (44) disposed axially of the chamber and extending to the interior of the chamber to enable the evacuation of the gaseous flow, from which the particles have been removed, the chamber further including, in its lower portion, an outlet opening (46) communicating with a discharge conduit (47), said conduit being closed at its lower end by a movable shutter (49) to provide a box for recovery of particles, the chamber being arranged such that the developer particles, after being separated from the gaseous flow int he chamber, are urged by gravity toward the discharge conduit and into the box: and a helical device (52) disposed in the discharge conduit (47) and in proximity with the outlet opening (46), the helical device having a surface the helical edge (53) of which is in contact with the internal wall of the discharge conduit, and the inclination of which is oriented in the same direction as that of the helical path of the solid particles to be transported by the gaseous flow, to prevent particles arriving in the recovery box from being re-aspirated by the rising gaseous flow which circulates above said helical device and finally escapes via the escape conduit, and wherein a pitch (P) of the helix of the helical device (52) is greater than 5 mm.

Claim 21

An apparatus for separating and recovering solid developer particles transported by a gaseous flow, comprising: a separation chamber (40) having an axis of revolution (45) disposed substantially vertically, the chamber having in its upper portion an admission conduit (43) for admitting gas into the chamber (40) and arranged so as to create a turbulent flow for a gaseous flow, laden with solid developer particles, and an escape conduit (44) disposed axially of the chamber and extending to the interior of the chamber to enable the evacuation of the gaseous flow, from which the particles have been removed, the chamber further including, in its lower portion, an outlet opening (46) communicating with a discharge conduit (47), said conduit being closed at its lower end by a movable shutter (49) to provide a box for recovery of particles, the chamber being arranged such that the developer particles, after being separated from the gaseous flow int he chamber, are urged by gravity toward the discharge conduit and into the box: and a helical device (52) disposed in the discharge conduit (47) and in proximity with the outlet opening (46), the helical device having a surface the helical edge (53) of which is in contact with the internal wall of the discharge conduit, and the inclination of which is oriented in the same direction as that of the helical path of the solid particles to be transported by the gaseous flow, to prevent particles arriving in the recovery box from being re-aspirated by the rising gaseous flow which circulates above said helical device and finally escapes via the escape conduit, and wherein a pitch (P) of the helix of the helical device (52) is greater than 5 mm.

Claim 22

An apparatus for separating and recovering solid developer particles transported by a gaseous flow, comprising: a separation chamber (40) having an axis of revolution (45) disposed substantially vertically, the chamber having in its upper portion an admission conduit (43) for admitting gas into the chamber (40) and arranged so as to create a turbulent flow for a gaseous flow, laden with solid developer particles, and an escape conduit (44) disposed axially of the chamber and extending to the interior of the chamber to enable the evacuation of the gaseous flow, from which the particles have been removed, the chamber further including, in its lower portion, an outlet opening (46) communicating with a discharge conduit (47), said conduit being closed at its lower end by a movable shutter (49) to provide a box for recovery of particles, the chamber being arranged such that the developer particles, after being separated from the gaseous flow in the chamber, are urged by gravity toward the discharge conduit and into the box; and a helical device (52) disposed int he discharge conduit (47) and in proximity with the outlet opening (46), the helical device having a surface the helical edge (53) of which is in contact with the internal wall of the discharge conduit, and the inclination of which is oriented in the same direction as that of the helical path of the solid particles to be transported by the gaseous flow, to prevent particles arriving in the recovery box from being re-aspirated by the rising gaseous flow which circulates above said helical device and finally escapes via the escape conduit, and wherein the separation chamber (40) comprises an upper cylindrical portion (41) joined to a lower conical portion (42), the lateral wall of the conical portion forming an angle (J) with the axis of revolution (45) of the chamber equal to at most 15°.

Claim 23

An apparatus for separating and recovering solid developer particles transported by a gaseous flow, comprising: a separation chamber (40) having an axis of revolution (45) disposed substantially vertically, the chamber having in its upper portion an admission conduit (43) for admitting gas into the chamber (40) and arranged so as to create a turbulent flow for a gaseous flow, laden with solid developer particles, and an escape conduit (44) disposed axially of the chamber and extending to the interior of the chamber to enable the evacuation of the gaseous flow, from which the particles have been removed, the chamber further including, in its lower portion, an outlet opening (46) communicating with a discharge conduit (47), said conduit being closed at its lower end by a movable shutter (49) to provide a box for recovery of particles, the chamber being arranged such that the developer particles, after being separated from the gaseous flow in the chamber, are urged by gravity toward the discharge conduit and into the box; and a helical device (52) disposed int he discharge conduit (47) and in proximity with the outlet opening (46), the helical device having a surface the helical edge (53) of which is in contact with the internal wall of the discharge conduit, and the inclination of which is oriented in the same direction as that of the helical path of the solid particles to be transported by the gaseous flow, to prevent particles arriving in the recovery box from being re-aspirated by the rising gaseous flow which circulates above said helical device and finally escapes via the escape conduit, and wherein the separation chamber (40) comprises an upper cylindrical portion (41) joined to a lower conical portion (42), the lateral wall of the conical portion forming an angle (J) with the axis of revolution (45) of the chamber equal to at most 15°.