Differential printing device

Patent metadata

Field	Value
Publication number	US-9649833-B2
Application number	US-201314907410-A
Country	US
Kind code	B2
Filing date	Jul 26, 2013
Priority date	Jul 26, 2013
Publication date	May 16, 2017
Grant date	May 16, 2017

Abstract

A differential printing device includes a first print drum including a first ring gear defined on an outside surface of the first print drum. The device also includes a second print drum including a second ring gear defined on an outside surface of the second print drum. A drive shaft that rotates the first print drum and the second print drum has a number of pinion gears to engage the first ring gear and the second ring gear. The number of pinion gears rotate the first print drum and the second print drum at different angular velocities.

First claim

What is claimed is:

1. A differential printing device comprising:
a first print drum comprising a first ring gear defined on an outside surface of the first print drum;
a second print drum coaxial to the first print drum comprising a second ring gear defined on an outside surface of the second print drum;
a drive shaft to rotate the first print drum and the second print drum, the drive shaft comprising a number of pinion gears to engage the first ring gear and the second ring gear;
in which the number of pinion gears rotate the first print drum and the second print drum at different angular velocities.

2. The device of claim 1 , in which teeth of the first ring gear face teeth of the second ring gear.

3. The device of claim 1 , further comprising:
a first speedometer to measure the angular velocity of the first print drum; and
a second speedometer to measure the angular velocity of the second print drum.

4. The device of claim 1 , in which the drive shaft supplies a single input torque to the first print drum and the second print drum that is apportioned differently to the first print drum and the second print drum.

5. The device of claim 1 , further comprising a relative velocity detector to detect the angular velocities of the first print drum and the second print drum relative to one another.

6. The device of claim 1 , wherein the number of pinion gears rotate the first print drum and the second print drum at different angular velocities by transfer of a different portion of input torque to the first print drum and the second print drum based on spin of the number of pinion gears.

7. The device of claim 1 , further comprising a carrier wherein the number of pinion gears spin with the carrier.

8. The device of claim 1 , wherein teeth of the number of pinion gears push teeth of the second ring gear to rotate the second print drum.

9. The device of claim 7 , wherein a number of teeth pushed of the first ring gear is different from a number of teeth pushed of a second ring gear.

10. A differential print drum comprising:
a first print drum rotably coupled to a drive shaft via a first pinion gear and first ring gear, the first pinion gear having multiple degrees of motion; and
a second print drum rotably coupled to the drive shaft via a second pinion gear and second ring gear, the second pinion gear having multiple degrees of motion and the second print drum coaxial to the first print drum;
in which the first print drum and the second print drum are driven by the drive shaft at different angular velocities relative to motion of the first ring gear and the second ring gear as caused by spin of the first pinion gear and the second pinion gear.

11. The print drum of claim 10 , in which the first print drum and the second print drum rotate independent of one another.

12. The print drum of claim 10 , in which the first print drum receives paper in a first orientation, and the second print drum receives paper in a second orientation.

13. The print drum of claim 10 , wherein the multiple degrees of motion of the first pinion gear and the second pinion gear include rotating about the drive shaft and spinning about a longitudinal axis of the respective pinion gear.

14. A differential printing system comprising:
a split print drum comprising:
a plurality of coaxial print drums positioned adjacent to one another;

a drive shaft comprising a differential mechanism to selectively rotate a number of print drums, wherein the differential mechanism comprises a number of pinion gears to selectively engage with a plurality of ring gears disposed on outside surfaces of the plurality of coaxial print drums; and
a power source to supply an input torque to the drive shaft based on the motion of the coaxial print drums relative to one another;
in which the number of coaxial print drums receive a number of passes of paper.

15. The system of claim 14 , in which the drive shaft passes longitudinally through the center of the plurality of coaxial print drums.

16. The system of claim 14 , further comprising a carrier to support the number of pinion gears.

17. The system of claim 14 , in which the power source rotates the drive shaft based on an angular velocity of the plurality of print drums relative to one another compared to a threshold amount.

18. The system of claim 14 , further comprising a locking mechanism to secure the plurality of coaxial print drums.

19. The system of claim 14 , further comprising a tension mechanism to control the tension of paper in the differential printing system.

Assignees

• Hewlett Packard Development Co Lp

Inventors

• Bell Jeffrey F

Classifications

• B41F13/02

  Conveying or guiding webs through presses or machines · CPC title

• B41F13/08

  Cylinders · CPC title

• B41F13/008 Primary

  Mechanical features of drives, e.g. gears, clutches · CPC title

• B41P2213/20

  Gearings · CPC title

• B41F3/58 Primary

  Driving, synchronising, or control gear · CPC title