Sliding valve vacuum holddown
AssigneeHewlett-Packard Company
InventorsJeffrey C. Madsen, Steven P. Downing
Life of this patent
Estimating the term…
Abstract
A vacuum holddown has a holddown member with an outer surface for temporarily capturing a flexible sheet material via a vacuum force distributed across the outer surface through discrete vacuum channels. A vacuum force valve mechanism abuts an inner surface of the holddown member in a selectable sliding engagement. The valve mechanism has a pattern of apertures therethrough in predetermined pattern such that discrete valve mechanism positions produce discrete vacuum force patterns at the outer surface of the holddown member.
Claims23
A vacuum holddown apparatus comprising:
- first means for distributing a vacuum force, having a first means outer surface and a first means inner surface, such that the first means outer surface is configured for receiving and holding flexible sheet materials there against by having a plurality of channels of a first predetermined pattern, each of the channels having a through port for coupling an associated channel with the vacuum force;
- and
- second means for distributing the vacuum force, having a second means outer surface and a second means inner surface, the second means outer surface abutting the first means inner surface in a substantially fluidically tight sliding engagement, the second means having a plurality of apertures therethrough, the plurality of apertures having a second predetermined pattern across the second means, such that sliding the second means relative to the first means causes redistribution of the vacuum force to the channels in accordance with the immediate alignment of the first means and the second means.
A method for distributing a vacuum holddown vacuum force to a first surface having a plurality of vacuum channels in a first predetermined pattern wherein each channel is separately ported to a second surface for drawing a vacuum therefrom, the channels adapted for securing a flexible sheet material to the first surface via influence of the vacuum force, the method comprising the steps of:
- adjacently to the second surface, mounting a valve means for redistributing the vacuum force between predetermined sets of channels wherein the valve means has a substantially identical shape and size of the second surface, the valve means having apertures therethrough arrayed in a second predetermined pattern;
- and
- selectively moving the valve means to align selected ones of the apertures to selected ones of the ports in accordance with producing a predetermined vacuum force distribution at the first surface.
A vacuum drum printer vacuum drum device comprising:
- a drum having a plurality of vacuum channels in a first predetermined array across a drum outer surface, each of the vacuum channels having a vacuum port fluidically coupling an associated vacuum channel to a drum inner surface;
- and
- mounted within the drum, at least one sleeve having a sleeve outer surface in sliding face-to-face contact with the drum inner surface and having apertures therethrough in a second predetermined array such that discrete sleeve positions produce discrete vacuum patterns at the outer surface of the drum.
Dependencies are inferred from the claim text.