Registration system for phasing simultaneously advancing webs of material having variable pitch lengths

• US 6,444,064 B1
• Filed: 02/01/2000
• Issued: 09/03/2002
• Est. Priority Date: 12/19/1997
• Status: Expired due to Term

• Current Assignee: The Procter & Gamble Company
• Original Assignee: The Procter & Gamble Company
• Inventors: Miller, Charles Phillip, Matsuda, Toshiyuki, Henry, Douglass Scott, Stephens, Alton Henry, King, Paul Kevin II
• Primary Examiner(s): Crispino, Richard
• Assistant Examiner(s): Purvis, Sue A.
• Application Number:
  US09/495,651
• Time in Patent Office: 945 Days
• Field of Search: 156/64, 156/350, 156/351, 156/229, 156/378, 156/494, 156/361, 156/362, 156/324, 226/30, 226/27, 226/28, 226/29
• US Class Current: 156/64
• CPC Class Codes: A61F 13/15772 Control
• CPC Class Codes: B65H 23/1886 Synchronising two or more webs

Abstract

Disclosed is a registration system and a method useful for controlling and correcting the phase and position of simultaneously advancing webs having pre-printed objects spaced at a pitch length characterized by small but significant pitch variation to a target web. Also disclosed are consumer products, such as disposable absorbent articles including the preprinted objects which were previously included in the webs phased before combining with a target web by utilizing the instant registration system. The pre-printed objects may include pre-printed, pre-bonded, pre-applied, pre-cut, or pre-glued objects or elements of disposable absorbent articles or registration marks produced on a separate independent process not control-linked to the instant registration method. The registration marks may be visible or normally invisible to the human eye.

Claims

1. A registration method for phasing simultaneously advancing webs of material having variable pitch lengths, the method comprising the steps of:

a. providing a continuous target web containing consecutively spaced target objects along a path at a first velocity, the target web having a target web pitch length between consecutive target objects;

b. providing a continuous controlled web of material preprinted with consecutively spaced preprinted objects along a path at a second velocity, the controlled web having a controlled web pitch length between consecutive preprinted objects;

c. detecting the preprinted objects of the controlled web by sensing by an optic that electronically strobes a resolver providing actual position data;

d. generating an error signal based upon the detection of the preprinted objects of the controlled web and comparing to a fixed target position constant;

e. adjusting the controlled web pitch length such that the controlled web pitch length is approximately equal to the target web pitch length to maintain registration due to pitch mismatch; and

f. adjusting the second velocity such that the preprinted objects are shifted toward the target objects on the target web.

2. The method of claim 1 further comprising a step of combining the target web and the controlled web such that the target objects and the preprinted objects are phased.

3. The method of claim 1 wherein the step of adjusting the controlled web pitch length includes on-goingly adjusting the tension in the controlled web.

4. The method of claim 1 wherein the step of detecting the preprinted objects includes a step of detecting electromagnetic wavelengths in the infrared (IR) spectrum from about 700 nm to about 2,500 nm emitted by the preprinted objects.

5. The method of claim 1 wherein the step of detecting the preprinted objects includes a step of detecting electromagnetic wavelengths in the near infrared (NIR) spectrum from about 700 nm to about 1,100 nm.