Motor control system and method for a rotary hole punch system

Patent metadata

Field	Value
Publication number	US-10071494-B2
Application number	US-201715424983-A
Country	US
Kind code	B2
Filing date	Feb 6, 2017
Priority date	Apr 22, 2014
Publication date	Sep 11, 2018
Grant date	Sep 11, 2018

Abstract

A sheet processing apparatus includes a punch mechanism disposed along a media path at a punch point at which a hole is to be punched through a punch location on a media sheet advancing along the media path. The punch mechanism includes a rotatable punch arm having a punch head, and a punch motor for rotating the punch arm. As the punch location on the advancing media sheet approaches the punch point, speed of the punch motor is controlled to adjust a rotational speed of the punch arm based on feedback signals associated with each of the punch motor and a media path motor used to advance the media sheet such that the punch head arrives at the punch point at substantially the same time as when the punch location on the media sheet arrives at the punch point.

First claim

What is claimed is:

1. A sheet processing apparatus, comprising:
a plurality of feed rolls disposed along a media path through the sheet processing apparatus;
a media path motor operatively coupled to the plurality of feed rolls for rotating the plurality of feed rolls to advance a media sheet along the media path;
a first sensing mechanism associated with the media path motor for sensing motion of the media path motor and providing a motion feedback signal associated therewith;
a punch mechanism disposed along the media path at a punch point at which a hole is to be punched through the media sheet advancing along the media path at a predetermined punch location on the advancing media sheet, the punch mechanism including:
a rotatable punch arm having a punch head at a free end thereof;
a punch motor operatively coupled to the punch arm for rotating the punch arm during a punching operation, the punch arm rotatable to the punch point at which the punch head is engageable with the media sheet to punch a hole through the advancing media sheet at the punch location while passing through the punch point; and
a second sensing mechanism associated with the punch motor for sensing motion of the punch motor and providing a position feedback signal associated therewith; and
a controller coupled to the media path motor, the punch motor, and the first and second sensing mechanisms, wherein as the punch location on the advancing media sheet approaches the punch point, the controller receives the feedback signals associated with each of the media path motor and the punch motor from the first and second sensing mechanisms, respectively, and controls a speed of the punch motor to adjust a rotational speed of the punch arm based on the feedback signals from both the first and second sensing mechanisms so that the punch head arrives at the punch point at substantially the same time as when the punch location on the advancing media sheet arrives at the punch point,
wherein when, during rotation, the punch arm arrives at a predetermined angular position following the punch point relative to a direction of the rotation of the punch arm, the controller adjusts the rotational speed of the punch arm to substantially reduce towards zero a difference between a circumferential travel distance of the punch head to the punch point and a travel distance of the punch location on the media sheet to the punch point.

2. The sheet processing apparatus of claim 1 , wherein the predetermined angular position corresponds to an angular position where a circumferential clearance gap of at least 5 mm is defined between the punch head and the advancing media sheet after the punch head engages the advancing media sheet.

3. The sheet processing apparatus of claim 1 , wherein when, during rotation, the punch arm arrives at a predetermined angular position before the punch point relative to a direction of the rotation of the punch arm, the controller adjusts the rotational speed of the punch arm to substantially match a linear speed of the punch head with a linear speed of the advancing media sheet as the punch head and punch location approaches the punch point, and wherein the predetermined angular position corresponds to an angular position where a circumferential clearance gap of at least 5 mm is defined between the punch head and the advancing media sheet before the punch head engages the advancing media sheet.

4. The sheet processing apparatus of claim 1 , wherein when, during rotation, the punch arm arrives at a predetermined angular position before the punch point relative to a direction of the rotation of the punch arm, the controller adjusts the rotational speed of the punch arm to substantially match a linear speed of the punch head with a linear speed of the advancing media sheet as the punch head and punch location approaches the punch point, and wherein the linear speed of the punch arm is about one percent slower than the linear speed of the advancing media sheet.

5. The sheet processing apparatus of claim 1 , wherein the controller employs active braking to control the speed of the punch motor.

6. The sheet processing apparatus of claim 1 , further comprising an edge sensor disposed along the media path and upstream of the punch point, wherein the controller begins to control the speed of the punch motor to adjust the rotational speed of the punch arm when the edge sensor detects a leading edge of the advancing media sheet.

7. The sheet processing apparatus of claim 1 , wherein the controller determines a position of the punch arm based on at least one of the position feedback signal from the second sensing mechanism and a position signal from a position sensor associated with the punch arm.

8. The sheet processing apparatus of claim 1 , further comprising a hole sensor disposed along the media path and downstream of the punch point for detecting a location of the hole punched through the advancing media sheet, wherein the controller controls the speed of the punch motor based on the detected location of the hole.

9. A sheet processing apparatus, comprising:
a plurality of feed rolls disposed along a media path through the sheet processing apparatus;
a media path motor operatively coupled to the plurality of feed rolls for rotating the plurality of feed rolls to advance a media sheet along the media path;
a punch assembly defining a punch point along the media path at which a hole is punchable through the advancing media sheet at a punch location thereon, the punch assembly including a rotatable punch arm having a punch head at a free end thereof;
a punch motor operatively coupled to the punch arm for driving the punch arm to rotate so that the punch head rotates to the punch point to engage the media sheet;
a controller coupled to the media path motor, the punch assembly, and the punch motor, the controller operative to control a rotational speed of the punch arm such that the punch head arrives at the punch point at substantially the same time as the punch location on the media sheet arrives at the punch point, wherein during a first portion of a rotational cycle of the punch arm before the punch head arrives at the punch point, the controller is operative to determine a travel distance of the punch location on the media sheet to the punch point and a circumferential travel distance of the punch head to the punch point, calculate a position error between the punch head and the punch location based on the difference between the travel distance and the circumferential travel distance, and adjust the rotational speed of the punch arm to substantially reduce the position error toward zero; and
further comprising an edge sensor disposed along the media path and upstream of the punch point, wherein the controller begins to control the rotational speed of the punch arm when the edge sensor detects a leading edge of the advancing media sheet.

10. A sheet processing apparatus, comprising:
a plurality of feed rolls disposed along a media path through the sheet processing apparatus;
a media path motor operatively coupled to the plurality of feed rolls for rotating the plurality of feed rolls to advance a media sheet along the media path;
a punch assembly defining a punch point along the media path at which a hole is punchable through the advancing media sheet at a punch location thereon, the punch assembly including a rotatable punch arm having a punch head at a free end thereof;
a punch motor operatively coupled to the punch arm for driving the punch arm to rotate so that the punch head rotates to the punch point to engage the media sheet;
a controller coupled to the media path motor, the punch assembly, and the punch motor, the controller operative

Assignees

• Lexmark Int Inc

Inventors

• Pantonial Roel Firmeza
• Reichert Brian Anthony
• Walker Andrew Keith

Classifications

• B26F1/02

  Perforating by punching, e.g. with relatively-reciprocating punch and bed · CPC title

• B26D5/086

  Electric, magnetic, piezoelectric, electro-magnetic means · CPC title

• B26F1/14

  Punching tools; Punching dies · CPC title

• B26D5/005

  Computer numerical control means · CPC title

• B26D5/20 Primary

  with interrelated action between the cutting member and work feed · CPC title