Single motor dynamic ribbon feedback system for a printer

Patent metadata

Field	Value
Publication number	US-10035367-B1
Application number	US-201715629050-A
Country	US
Kind code	B1
Filing date	Jun 21, 2017
Priority date	Jun 21, 2017
Publication date	Jul 31, 2018
Grant date	Jul 31, 2018

Abstract

A printer with a single motor system to match torques between ribbon supply and ribbon take-up is provided. The printer comprises a ribbon supply spindle, a take-up ribbon spindle, sensors to output ribbon width and diameter at ribbon supply, and a sensor which outputs ribbon diameter at ribbon take-up. The printer is provided with a drive system providing rotation to the ribbon supply via tension on the ribbon loaded on the ribbon supply spindle and taken-up on the take-up ribbon spindle. Firmware, communicatively linked to the sensors and the drive system, is configured to calculate ribbon tension at the ribbon supply spindle, to calculate the torque required on the ribbon on the ribbon take-up spindle to match the ribbon tension at the take-up spindle to the ribbon tension at the ribbon supply spindle, and to adjust the drive system to match these torques.

First claim

The invention claimed is:

1. A printer for printing media comprising:
a rotatable ribbon supply spindle;
a rotatable take-up ribbon spindle;
at least one sensor that outputs ribbon width and diameter of a ribbon loaded on the rotatable ribbon supply spindle;
a sensor which outputs ribbon diameter on the ribbon loaded on the rotatable take-up ribbon spindle;
a drive system configured to rotate the rotatable take-up ribbon spindle, the drive system further providing rotation to the rotatable ribbon supply via tension on the ribbon loaded on the rotatable ribbon supply spindle and taken-up on the rotatable take-up ribbon spindle;
firmware, the firmware being communicatively linked to the at least one sensor for determining ribbon width and diameter of the ribbon loaded on the rotatable ribbon supply spindle, to the sensor for determining ribbon diameter on the ribbon loaded on the rotatable take-up ribbon spindle, and to the drive system;
the firmware being configured to calculate ribbon tension at the ribbon supply spindle from the output of the at least one sensor on the rotatable ribbon supply spindle;
the firmware being further configured to calculate the torque on the ribbon on the rotatable ribbon take-up spindle required to match the ribbon tension at the take-up spindle to the ribbon tension at the rotatable ribbon supply spindle based upon the calculated total tension at the rotatable ribbon supply spindle and the output from the sensor on the ribbon take-up spindle; and
the firmware being configured to adjust the drive system so that the torque at the rotatable take-up spindle is the calculated torque required to match the ribbon tension at the rotatable ribbon take-up spindle to the ribbon tension at the rotatable ribbon supply spindle.

2. The printer of claim 1 , wherein the at least one sensor that outputs ribbon width and diameter of a ribbon loaded on the rotatable ribbon supply spindle is comprised of an encoder sensor that outputs the diameter of the ribbon loaded on the rotatable ribbon supply spindle, the encoder sensor being disposed on a base of the rotatable ribbon supply spindle; and a second sensor that outputs the width of the ribbon loaded on the rotatable ribbon supply spindle, the second sensor being disposed on the rotatable ribbon supply spindle.

3. The printer of claim 1 , wherein the ribbon width is proportional to the torque at the rotatable ribbon supply spindle.

4. The printer of claim 2 , wherein the encoder sensor rotates with the rotatable supply spindle; the encoder sensor rotation rate being proportional to the radius of the ribbon loaded on the rotatable ribbon supply spindle; and the encoder sensor on the ribbon supply spindle being configured to determine the rotation rate based upon a number of encoder interrupts for a given period.

5. The printer of claim 1 , wherein the sensor which outputs ribbon diameter on the ribbon loaded on the rotatable take-up ribbon spindle is an encoder sensor that rotates with the rotatable ribbon take-up spindle; the encoder sensor at the rotatable ribbon take-up spindle has a rotation rate proportional to the ribbon radius at the rotatable ribbon take-up spindle; the encoder sensor at the rotatable ribbon take-up spindle being configured determine the rotation rate based upon a number of encoder interrupts for a given period.

6. The printer of claim 1 , wherein the firmware calculation for ribbon tension at the rotatable ribbon supply spindle is SRT/SRR, where SRT is the torque at the supply ribbon spindle, and SRR is the supply ribbon radius.

7. The printer of claim 6 , wherein the firmware calculation of torque on the ribbon on the rotatable ribbon take-up spindle required to match the ribbon tension at the take-up spindle to the ribbon tension at the rotatable ribbon supply spindle is (SRT/SRR)*TRR, where TRR is the radius of the ribbon at the rotatable ribbon take-up spindle.

8. The printer of claim 1 , wherein the drive system is an electronic motor; and wherein the firmware is configured to adjust current to the motor so that the torque at the rotatable take-up spindle is the calculated torque required to match the ribbon tension at the rotatable ribbon take-up spindle to the ribbon tension at the rotatable ribbon supply spindle.

9. The printer of claim 1 , further comprising spring wraps on the rotatable ribbon supply spindle, the spring wraps providing torque to the ribbon on the rotatable ribbon supply spindle.

10. The printer of claim 1 , wherein the firmware is configured to periodically adjust the drive system based upon periodic calculations of the torque on the ribbon on the rotatable ribbon take-up spindle required to match the ribbon tension at the take-up spindle to the ribbon tension at the rotatable ribbon supply spindle based upon the calculated total tension at the rotatable ribbon supply spindle and the output from the sensor on the ribbon take-up spindle.

11. A printer comprising:
a rotatable ribbon supply spindle;
an encoder sensor for determining the diameter of a ribbon loaded on the ribbon supply spindle;
a sensor for determining width of the ribbon loaded on the ribbon supply spindle;
a rotatable ribbon take-up spindle for taking up the ribbon;
an encoder sensor on the ribbon take-up spindle for determining the diameter of the ribbon on the take-up spindle;
a drive system configured to rotate the ribbon take-up spindle, the drive system being powered by an electric power supply, the drive system further providing rotation to the rotatable ribbon supply spindle via tension on a ribbon loaded on the rotatable ribbon supply spindle and taken-upon the rotatable take-up ribbon spindle;
firmware, the firmware being communicatively linked to receive sensor outputs from the encoder sensor on the ribbon supply spindle, the sensor for determining ribbon width, and the encoder sensor on the ribbon take-up spindle;
the firmware being configured to determine torque in the ribbon at the supply spindle based upon the output from the sensor for determining width of the ribbon on the ribbon supply spindle;
the firmware being configured to calculate the total tension in the ribbon supply based upon the torque determined at in the ribbon at the supply spindle and based upon the output from the encoder sensor on the ribbon supply spindle, the firmware calculation being SRT/SRR, where SRT is Supply Ribbon Torque and SRR is Supply Ribbon Radius;
the firmware being further configured to calculate the torque in the rotatable ribbon take-up spindle required to match the ribbon tension in the take-up spindle to the ribbon tension in the supply spindle based upon the calculated total tension in the ribbon supply and the output from the encoder sensor on the ribbon take-up spindle, the firmware calculation being (SRT/SRR)*TRR, where TRR is the radius of the ribbon at the take-up spindle;
the firmware being communicatively linked to the electric power supply and configured to control current supplied to the drive system, the current being proportional to a rate of rotation of the drive system and the take-up spindle; and
the firmware being configured to adjust the current supplied to the drive system so that the torque at the take-up spindle is the calculated torque required to match the ribbon tension in the take-up spindle to the ribbon tension in the supply spindle.

12. The printer of claim 11 , further comprising spring wraps on the rotatable ribbon supply spindle, the spring wraps securing the ribbon on the rotatable ribbon supply spindle.

13. The printer of claim 12 , wherein the ribbon width is proportional to the torque at the rotatable ribbon supply spindle.

Assignees

• Datamax Oneil Corp

Inventors

• Yap Yaw Horng
• Wong Chin Young
• Chua Ching Hong

Classifications

• B41J17/08

  Feed independent of the record-paper feed · CPC title

• B41J33/22 Primary

  by gears or pulleys · CPC title

• B41J33/24

  with drive applied directly to ribbon · CPC title

• B41J33/34 Primary

  driven by motors independently of the machine as a whole · CPC title

• B41J2/325

  by selective transfer of ink from ink carrier, e.g. from ink ribbon or sheet · CPC title