US 7,739,952 B2Granted

Printing apparatus and method of tension control

AssigneeDainippon Screen Mfg. Co., Ltd.

InventorTakashi Sakamoto

Life of this patent

Estimating the term…

Loading patent…

Abstract

A printing apparatus performs printing on a web of printing paper while transporting the printing paper along a transport path. The printing apparatus includes a first transport mechanism located upstream in the transport path, and a second transport mechanism located downstream in the transport path. The transport speed of the printing paper in the first transport mechanism is controlled so that a tension value measured by a first tension sensor provided near the first transport mechanism approaches a predetermined value. The transport speed of the printing paper in the second transport mechanism is controlled so that a tension value measured by a second tension sensor provided near the second transport mechanism approaches the tension value measured by the first tension sensor. Thus, the tension of the printing paper is maintained at the predetermined value in the two locations along the transport path. The printing apparatus presents no hunting problem because the tension control using the predetermined value as a target value is effected only in the first transport mechanism.

Claims12

Dependent claims

A printing apparatus for printing on a web of printing paper while transporting the printing paper along a predetermined transport path, comprising:

a plurality of measuring parts for measuring the tension of said printing paper in a plurality of locations, respectively, along said transport path;
a plurality of transport parts for transporting said printing paper near said plurality of measuring parts, respectively;
and
a controller for controlling the transport speed of said printing paper in said plurality of transport parts, based on tension values measured by said plurality of measuring parts,
(i) said controller controlling the transport speed of said printing paper in a first transport part with a controlling target so that a tension value measured by one of said plurality of measuring parts which is located near said first transport part approaches a predetermined value, said first transport part being located most upstream among said plurality of transport parts,
(ii) said controller controlling the transport speed of said printing paper in a second transport part with the controlling target so that tension values measured by two of said plurality of measuring parts which are located immediately upstream and downstream of said second transport part are referenced and that the two measured tension values approach each other, said second transport part being included among said plurality of transport parts, and
only said first transport part among said plurality of transport parts being controlled with a control target using said predetermined value as a target value.

4 more elements

A method of controlling the tension of a web of printing paper in a printing apparatus, said printing apparatus printing on said printing paper while transporting said printing paper along a predetermined transport path, said method comprising the steps of:

(a) measuring the tension of said printing paper in a plurality of measuring positions along said transport path;
and
(b) controlling the transport speed of said printing paper in a plurality of transport positions provided near said plurality of measuring positions, respectively, wherein, in said step (b),
(i) the transport speed of said printing paper in a first transport position is controlled with a controlling target so that a tension value measured in one of said plurality of measuring positions which is located near said first transport position approaches a predetermined value, said first transport position being located most upstream among said plurality of transport positions,
(ii) the transport speed of said printing paper in a second transport position is controlled with the controlling target so that tension values measured in two of said plurality of measuring positions which are located immediately upstream and downstream of said second transport position are referenced and that the two measured tension values approach each other, said second transport position being included among said plurality of transport positions, and
only said first transport position among said plurality of transport positions being controlled with a control target using said predetermined value as a target value.

3 more elements

Dependencies are inferred from the claim text.

Facts

Application: 11/515,895Filed 6 Sep 2006
Priority: JP 2005-2589657 Sep 2005
Published: US 2007/0051264 A18 Mar 2007
Granted: 22 Jun 2010
Term ends: Not estimatedThe source records don’t support an estimate.

Classification9 codes

B41F 13/02
Common details of rotary presses or machines: conveying or guiding webs through presses or machines
B41J 3/60
Typewriters or selective printing or marking mechanisms characterised by the purpose for which they are constructed: for printing on both faces of…
B41J 15/16
Devices or arrangements of selective printing mechanisms, e.g. ink-jet printers or thermal printers, specially adapted for supporting or…
B65H 23/1888
In connection with running-web: and controlling web tension