Transport with media hold down for inkjet printers

Patent metadata

Field	Value
Publication number	US-9636930-B1
Application number	US-201615150841-A
Country	US
Kind code	B1
Filing date	May 10, 2016
Priority date	May 10, 2016
Publication date	May 2, 2017
Grant date	May 2, 2017

Abstract

A transport with media hold down is used with an inkjet printer. A plurality of spar links and vacuum links are connected pivotally together to form an endless belt orbiting around drive wheels and driven wheels. Vacuum links have hollow chambers to hold the media sheet against the endless belt using vacuum. At least one spar is received in a slot on a spar link. The spar extends above the link to receive the media sheet. The spar moves into a clamping position by a cam and follower to clamp the media sheet against the spar link. The media sheet will thus pass beneath the inkjet print head without contact. The spar moves into an extended position by the cam and follower to release the media sheet. The spar moves into a retracted position below the spar link surface by the cam and follower to allow the media sheet to exit the transport.

First claim

What is claimed is:

1. A transport with media hold down for use in connection with an inkjet printer having an inkjet print head, and a media sheet having a lead edge and a trail edge, the media sheet moving in a process direction along a process path, the transport with media hold down comprising:
a frame extending longitudinally in the process direction from a first end to an opposite second end;
at least one first axle mounted on the frame at the first end;
a pair of driven wheels mounted for rotation on the at least one first axle;
at least one second axle mounted on the frame at the second end;
a pair of drive wheels mounted for rotation on the at least one second axle;
at least one drive motor operatively driving at least one of the drive wheels;
a plurality of links operatively connected together, each link extending between opposite ends transversely to the process direction, each link having two opposed generally parallel link edges, each link edge being juxtaposed with an adjacent link edge on each adjacent link, the plurality of links being operatively drivingly attached to the drive wheels, each link being adapted for pivotal motion with respect to each adjacent link, each link having a link surface facing outward, the plurality of links being adapted for holding the media sheet generally flat against each link surface and conveying the media sheet in the process direction, at least one of the plurality of links being a spar link, and the remaining links being vacuum links;
at least one spar extending between opposite ends juxtaposed with the spar link opposite ends, the spar link having a spar link surface facing outward, the spar link having a slot extending through the spar link surface to receive the spar, the spar being adapted to move into a retracted position below the spar link surface, the spar being adapted to move into an extended position above the spar link surface, the spar having a clamp flange, the spar being adapted to move into a clamping position with the media sheet lead edge sandwiched between the clamp flange and the spar link surface, so as to hold the media sheet lead edge clamped against the spar link surface, wherein the media sheet will pass beneath the inkjet print head without contacting the inkjet print head;
at least one lift cam having an entry portion with an entry profile disposed adjacent the first end, the lift cam having an exit portion with an exit profile disposed adjacent the second end; and
at least one lift follower attached to the at least one spar link, the spar being operatively connected to the lift follower; wherein
the lift follower is adapted to follow the lift cam entry profile so as to move the spar from the retracted position to the extended position to receive the media sheet and to the clamping position to clamp the media sheet; and
the lift follower is adapted to follow the lift cam exit profile so as to move the spar from the clamping position to the extended position to release the media sheet from the clamping position and to the retracted position, allowing the media sheet to exit the transport.

2. The transport with media hold down of claim 1 , further comprising an endless belt formed by the plurality of links operatively connected together, the endless belt extending partway around the drive wheels and partway around the driven wheels, the endless belt extending between the drive wheels and the driven wheels, the endless belt being operatively drivingly attached to the drive wheels so as to be driven in an orbital motion around the drive wheels and the driven wheels.

3. The transport with media hold down of claim 2 , further comprising:
a vacuum plenum disposed beneath the endless belt;
a vacuum source communicating with the vacuum plenum to supply vacuum;
wherein the vacuum links each further comprise:
a hollow chamber attached to the vacuum link below the link surface, the hollow chamber being disposed above the vacuum plenum, the hollow chamber having apertures therethrough communicating with the vacuum plenum; and
a vacuum link surface facing outward away from the endless belt, the vacuum link surface having a plurality of holes therethrough communicating with the hollow chamber so as to apply vacuum to the media sheet for holding the media sheet generally flat against the vacuum link surface as the links move over the vacuum plenum in the process direction.

4. The transport with media hold down of claim 3 , further comprising:
the pair of drive wheels further comprises a left drive wheel and a right drive wheel, the left and right drive wheels being mounted for rotation on the at least one second axle, the left and right drive wheels each having an outer rim with a circumference, an inner rim with a circumference, the inner rim being smaller in diameter than the outer rim, and a shoulder extending between the outer rim and the inner rim;
the pair of driven wheels further comprises a left driven wheel and a right driven wheel, the left and right driven wheels being mounted for rotation on the at least one first axle, the left and right driven wheels each having an outer rim with a circumference, an inner rim with a circumference, the inner rim being smaller in diameter than the outer rim, and a shoulder extending between the outer rim and the inner rim; and
the vacuum links further comprise each vacuum link extending between a left end and an opposite right end, each vacuum link having a left tracking pin adjacent the left end, the left tracking pin being adapted to ride on the inner rim and against the shoulder of the left drive wheel and the left driven wheel, each vacuum link having a right tracking pin adjacent the right end, the right tracking pin being adapted to ride on the inner rim and against the shoulder of the right drive wheel and the right driven wheel, so as to retain the endless belt tracking generally centered on the transport.

5. The transport with media hold down of claim 2 , wherein:
the pair of drive wheels further comprises a left drive wheel and a right drive wheel, the left and right drive wheels being mounted for rotation on the at least one second axle, the left and right drive wheels each having an outer rim with a circumference, each outer rim having a plurality of teeth projecting radially outward therefrom, the teeth being spaced uniformly apart around the circumference; and
the plurality of links further comprises each link extending between a left end and an opposite right end, each link having a left drive hole adjacent the left end, the left drive hole being adapted to receive and release a one of the left drive wheel teeth, each link having a right drive hole adjacent the right end, the right drive hole being adapted to receive and release a one of the right drive wheel teeth, so as to operatively drivingly attach the endless belt to the drive wheels.

6. The transport with media hold down of claim 1 , further comprising at least one flexible drive belt attached to each link of the plurality of links to pivotally connect each link together and adapted to operatively move the plurality of links in an orbital motion around the drive wheels and the driven wheels.

7. The transport with media hold down of claim 1 , further comprising:
at least one tilt cam having an entry portion with an entry profile juxtaposed with the lift cam entry portion, the tilt cam having an exit portion with an exit profile juxtaposed with the lift cam exit portion; and
at least one tilt follower operatively connected to the at least one spar link, the spar being mounted on the tilt follower; wherein
the spar is adapted to move into a tilted position, so as to pass through the spar link slot and into an upright position prior to the clamping position;
the tilt follower is ad

Assignees

• Xerox Corp

Inventors

• Leighton Roger G
• Leo Michael F

Classifications

• B41J11/007 Primary

  Conveyor belts or like feeding devices · CPC title

• B65H29/04

  the grippers being carried by endless chains or bands · CPC title

• B65H29/02

  by mechanical grippers engaging the leading edge only of the articles · CPC title

• B65H5/085

  by combinations of endless conveyors and grippers (suction belts B65H5/224) · CPC title

• B41J13/10

  Sheet holders, retainers {, movable guides}, or stationary guides · CPC title