Vacuum platen

Patent metadata

Field	Value
Publication number	US-9669641-B2
Application number	US-201514937657-A
Country	US
Kind code	B2
Filing date	Nov 10, 2015
Priority date	Nov 11, 2014
Publication date	Jun 6, 2017
Grant date	Jun 6, 2017

Abstract

A vacuum platen for media sheets has a sheet support wall formed with a plurality of perforations and a number of chambers formed on a bottom side of the sheet support wall. Each of the chambers is directly connected to a vacuum source. Each chamber contains an acoustic barrier member arranged to divide the chamber into at least two sub-chambers such that the sub-chambers are in fluid communication with one another and have overlapping contours when seen in a direction normal to the plane of the sheet support wall.

First claim

What is claimed is:

1. A vacuum platen for media sheets, said vacuum platen comprising:
a sheet support wall formed with a plurality of perforations and a sheet supporting surface; and
a number of chambers formed on a bottom side of the sheet support wall,
wherein each of said number of chambers is to in fluid communication with a vacuum source and the plurality of perforations,
wherein each of said number of chambers contains an acoustic barrier member arranged to divide the chamber into at least two sub-chambers such that the at least two sub-chambers are in fluid communication with one another, and wherein the acoustic barrier member extends at an acute angle to a direction normal to the sheet supporting surface of the sheet support wall, such that a height of each sub-chamber, as measured in the direction normal to the sheet support wall, varies over a width direction of the chamber to reduce acoustic resonance oscillations from being excited in the at least two sub-chambers during operation.

2. The vacuum platen according to claim 1 , wherein the acoustic barrier member is a strip member having internal holes formed through an intermediate portion thereof and/or recesses formed in at least one edge thereof, for establishing the fluid communication between the at least two sub-chambers.

3. The vacuum platen according to claim 1 , wherein the acoustic barrier member is made of plastic.

4. The vacuum platen according to claim 1 , wherein the at least two sub-chambers have overlapping contours when viewed in a direction both parallel to the sheet supporting surface of the sheet support wall and to the width direction of the chamber.

5. The vacuum platen according to claim 1 , wherein the number of chambers are parallel channels extending along the bottom side of the sheet support wall.

6. The vacuum platen according to claim 5 , wherein when viewed in a direction both parallel to the sheet supporting surface of the sheet support wall and perpendicular to the width direction of each the chamber, each of the parallel channels have a cross-section with at least four sides.

7. The vacuum platen according to claim 6 , wherein the acoustic barrier member is a flat strip member inserted into each of the parallel channels, so as to extend along a diagonal of the cross-section.

8. The vacuum platen according to claim 6 , wherein the sheet support wall, a bottom wall and the chambers formed between the sheet support wall and the bottom wall are constituted by an extruded profile member.

9. The vacuum platen according to claim 8 , wherein the number of chambers are separated from one another by cooling channels that are adapted to circulate a cooling medium through the profile member.

10. The vacuum platen according to claim 6 , wherein each of the sub-chambers has a triangular cross-section.

11. The vacuum platen according to claim 1 , wherein the perforations in the sheet support wall extend directly into the chambers.

12. The vacuum platen according to claim 1 , have overlapping contours when viewed in a direction normal to the sheet supporting surface of the sheet support wall.

Assignees

• Océ-Technologies B V

Inventors

• Holtman Lodewijk T
• Van Der Mullen Alphonse L J M

Classifications

• B41J11/06

  Flat page-size platens {or smaller flat platens having a greater size than line-size platens (B41J11/0085 takes precedence)} · CPC title

• B41J11/0085 Primary

  Using suction for maintaining printing material flat (on rotatable drums B41J13/226) · CPC title