Vacuum tray fluid-jet start-up system
First Claim
1. In a fluid jet printing device of the type having an orifice plate structure including an orifice plate for generating an array of droplet streams generally parallel to one another for disposition on a substrate, apparatus for starting the flow of fluid droplet streams through the orifices of the orifice plate, comprising:
- means defining a chamber and a margin about said chamber;
said means being movable between a first position with said margin substantially sealing about the orifice plate structure with the orifices within said margin for receiving the droplet streams flowing through the orifices of the orifice plate and a second position spaced from the orifice plate structure; and
means for establishing a pressure gradient across the orifice plate including means for applying a vacuum to the chamber when the chamber-defining means lies in said first position to draw fluid from the opposite side of the orifice plate through the orifices into said chamber to aid in straight, generally parallel, fluid droplet stream formation.
8 Assignments
0 Petitions
Accused Products
Abstract
A tray for a fluid-jet printing device for starting fluid-jet streams issuing from an orifice plate in a direction substantially perpendicular to the orifice plate. The tray includes an elongated box-like structure movable between various positions, including a sealing position below the orifice plate for drawing a vacuum through the orifice plate and facilitating flow of fluid from a plenum chamber above the orifice plate through the orifice plate for start-up. The tray is provided with backlighting such that, upon movement of the tray into a second position, the fluid streams issuing from the orifice plate may be visually observed against the backlighting to ensure proper start-up. Thereafter, the tray is moved to subsequent positions enabling location of the charging and deflection electrodes and droplet catcher structure below the orifice plate, as well as the substrate on which the printing will be effected.
-
Citations
23 Claims
-
1. In a fluid jet printing device of the type having an orifice plate structure including an orifice plate for generating an array of droplet streams generally parallel to one another for disposition on a substrate, apparatus for starting the flow of fluid droplet streams through the orifices of the orifice plate, comprising:
-
means defining a chamber and a margin about said chamber; said means being movable between a first position with said margin substantially sealing about the orifice plate structure with the orifices within said margin for receiving the droplet streams flowing through the orifices of the orifice plate and a second position spaced from the orifice plate structure; and means for establishing a pressure gradient across the orifice plate including means for applying a vacuum to the chamber when the chamber-defining means lies in said first position to draw fluid from the opposite side of the orifice plate through the orifices into said chamber to aid in straight, generally parallel, fluid droplet stream formation. - View Dependent Claims (2, 3, 4)
-
-
5. A method for starting the flow of fluid droplet streams through the orifices of an orifice plate in a fluid-jet printing device, comprising the steps of:
-
(a) providing a fluid droplet catching tray in a position in sealing engagement about the orifices of the orifice plate structure; and (b) generating a pressure gradient across the orifice plate by applying a vacuum to the tray while introducing fluid from the opposite side of the orifice plate through the orifices into said tray whereby the pressure gradient across the orifices acts on the fluid to aid in the formation of straight, generally parallel, fluid droplet streams issuing generally normal to the orifice plate. - View Dependent Claims (6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16)
-
-
17. A fluid-jet apparatus comprising:
-
means defining a fluid plenum having a fluid inlet and an orifice plate forming a wall thereof, said orifice plate having an outside face and defining a plurality of orifices through which fluid from said plenum may be ejected to form generally parallel filaments which break up into droplet streams; means including electrostatic charging and deflection electrodes for controlling the droplets; and means for establishing a pressure gradient across the orifice plate including means for exposing the outside face of said orifice plate to a subatmospheric pressure during start-up of said apparatus whereby the pressure gradient across the orifices assists the formation of the straight, generally parallel droplet streams. - View Dependent Claims (18, 19, 20, 21, 22, 23)
-
Specification