Printing system

• US 20020081132A1
• Filed: 12/04/2001
• Published: 06/27/2002
• Est. Priority Date: 12/22/2000
• Status: Active Grant

• Current Assignee: Hitachi Printing Solutions, Ltd. (Ricoh Company Limited)
• Original Assignee: Hitachi Printing Solutions, Ltd. (Ricoh Company Limited)
• Inventors: Mizuno, Masahiro, Kikuchi, Soushi, Nakazawa, Souichi, Miyamoto, Atsushi, Kikuchi, Toru, Yokokawa, Shuho, Aita, Satoshi
• Granted Patent: US 6,650,864 B2
• Time in Patent Office: Days
• US Class Current: 399/384
• CPC Class Codes: B41J 11/46 by marks or formations on the paper being fed
• CPC Class Codes: B41J 3/60 for printing on both faces of the printing material
• CPC Class Codes: G03G 2215/00021 Plural substantially independent image forming units in cooperation, e.g. for duplex, colour or high-speed simplex

Abstract

A printing system having a first printer apparatus for forming an image on a first plane of a web having no feed holes and a second printer apparatus provided at a post stage of the first printer apparatus for forming an image on a second plane of said web. The first printer apparatus (P1) is operable to form a position-alignment mark (Rm) at a predesignated position on each page of a web (W). This position-alignment mark (Rm) is detected by mark detection means (16) of the second printer apparatus (P2). Control means (17) is provided for controlling an appropriate web transport speed so that both the generation timing of a web feed control signal (CPF-N signal) being generated with preset cyclic periods and the generation timing of a mark detection signal as issued from the mark detection means through detection of the position-alignment mark (Rm) are kept constant in phase.

Claims

1. A printing system having a first printer apparatus for forming an image on a first plane of a web having no feed holes and a second printer apparatus provided at a post stage of the first printer apparatus for forming an image on a second plane of said web, characterized in that

at least the first printer apparatus has mark formation means for forming a position alignment mark at a predesignated position on each page of said web, and

at least the second printer apparatus has mark detection means for detecting said position alignment mark and control means for generating a web feed control signal once per preset period and for causing the generation timing of said web feed control signal to be identical in phase with the generation timing of a mark detection signal as issued from said mark detection means through detection of said position alignment mark.

2. The printing system as recited in claim 1, characterized in that said control means includes means for controlling the transport speed of said web.

3. The printing system as recited in claim 1, characterized in that at least the second printer apparatus has an image carrying body for temporarily holding said image and that said control means includes means for controlling synchronization of the transport speed of said web and a travel speed of said image carrying body.

4. The printing system as recited in claim 1, characterized in that said control means includes storage means for storing therein the length of a time as taken from issuance of said web feed control signal to detection of said position alignment mark by said mark detection means whenever each position alignment mark is detected, arithmetic processing means for arithmetically determining a difference between new data being stored in said storage means and old data as has been stored before its one preceding page, and means for controlling the transport speed of said web based on an output of said arithmetic processing means.

5. The printing system as recited in claim 1, characterized in that at least the second printer apparatus has an image carrying body for temporally holding said image and that said control means includes storage means for storing therein the length of a time as taken from issuance of said web feed control signal to detection of said position alignment mark by said mark detection means whenever each position alignment mark is detected, arithmetic processing means for arithmetically determining a difference between new data being stored in said storage means and old data as has been stored before its one preceding page, and means for controlling the transport speed of said web based on an output of said arithmetic processing means.

6. The printing system as recited in claim 1, characterized by comprising detection period regulation means for enabling detection of said position alignment mark by said mark detection means within a preset time period only.

7. The printing system as recited in claim 1, characterized in that at least the first printer apparatus comprises photographic fixing means for adding at least heat to the web presently holding said image to thereby photographically fix said image on said web.