Browse Prior Art Database

DEVELOPER FLOW CONTROL ARRANGEMENT FOR A XEROGRAPHIC MACHINE

IP.com Disclosure Number: IPCOM000023663D
Original Publication Date: 1978-Oct-31
Included in the Prior Art Database: 2004-Mar-31
Document File: 2 page(s) / 242K

Publishing Venue

Xerox Disclosure Journal

Abstract

Various systems are known to continually monitor toner con-centration and to replenish toner supply as required. The Automatic Development Control unit (ADC) shown in the figure contains an optical toner sensor arrangement which typically includes NESA plates on which toner is deposited. The ADC unit measures the optical density of the developer flowing through the ADC unit as well as the optical density of toner deposited on the MESA plates. In order to achieve an accurate measurement of the optical density of the developer flow, the flow must be steadily maintained, i.e., flow variations can be sensed as changes in the "developability" of the developer. A steady flow is accomplished by placing two cones, 4 and 6, one above the other. The outlet 8 of upper cone 4 should be lower than the top surface of lower cone 6, and the orifice diameter of outlet 8 should be larger than the orifice diameter of outlet 10 of lower cone 6. A typical design would also require that the lower cone 6 be flush with the ADC orifice 12 and have the same size opening. The cone wall angles should be steep relative to vertical with maximum angles of approximately 40°. Assuming the interior cone surfaces are sufficiently smooth and the upper cone is at least partially full at all times, a steady developer flow will be maintained into the ADC unit.

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XEROX DISCLOSURE JOURNAL

DEVELOPER FLOW CONTROL ARRANGE- MENT FOR A XEROGRAPHIC MACHINE

James R. Norton

CONE ANGLES

S

Proposed Classification
U.S. Cl. 118/653
Int. Cl. G03g 15/08

Various systems are known to continually monitor toner con-
centration and to replenish toner supply as required. The
Automatic Development Control unit (ADC) shown in the figure
contains an optical toner sensor arrangement which typically
includes NESA plates on which toner is deposited. The ADC
unit measures the optical density of the developer flowing
through the ADC unit as well as the optical density of toner
deposited on the MESA plates. In order to achieve an accurate
measurement of the optical density of the developer flow, the
flow must be steadily maintained, i.e., flow variations can be
sensed as changes in the "developability" of the developer. A
steady flow is accomplished by placing two cones, 4 and 6, one
above the other. The outlet 8 of upper cone 4 should be lower
than the top surface of lower cone 6, and the orifice diameter
of outlet 8 should be larger than the orifice diameter of
outlet 10 of lower cone 6. A typical design would also require
that the lower cone 6 be flush with the ADC orifice 12 and have
the same size opening. The cone wall angles should be steep
relative to vertical with maximum angles of approximately 40°.
Assuming the interior cone surfaces are sufficiently smooth
and the upper cone is at least partially full at all times, a
steady developer flow will be maintained into...