Electrophotographic printers having spatial self-compensation for image cylinder runout

Patent metadata

Field	Value
Publication number	US-9316989-B1
Application number	US-201514606042-A
Country	US
Kind code	B1
Filing date	Jan 27, 2015
Priority date	Jan 27, 2015
Publication date	Apr 19, 2016
Grant date	Apr 19, 2016

Abstract

An image forming device includes at least two image cylinders that rotate with a time varying velocity; at least two image cylinder gears respectively attached to each image cylinder; and at least one pinion gear that drives the at least two image cylinder gears. The time varying velocity of the image cylinder gear is due to a runout of the pinion gear. The spacing between the centers of the image cylinders is determined by
S 12 = k ⁢ ⁢ π ⁢ ⁢ D p + α 360 ⁢ π ⁢ ⁢ D p
where S 12 is the distance between the centers of the two image cylinders gears; k is an integer; α is the angle between the pitch point of the two gears; and D p is the diameter of the pinion gear.

First claim

The invention claimed is:

1. An image forming device comprising:
at least two image cylinders that rotate with a time varying velocity;
at least two image cylinder gears respectively attached to each image cylinder; and
at least one pinion gear that drives the at least two image cylinder gears; wherein the time varying velocity of the image cylinder gear is due to a runout of the pinion gear;
wherein the spacing between the centers of the image cylinders is determined by

S
12

=

k
⁢

⁢
π
⁢

⁢

D
p

+

α
360

⁢
π
⁢

⁢

D
p

where S 12 is the distance between the centers of the two image cylinders gears; k is an integer; α is the angle between the pitch point of the two gears; and D p is the pitch the diameter of the pinion gear.

2. The image forming device of claim 1 , wherein the time varying velocity of the image cylinder is reproducible and periodic.

3. The image forming device as in claim 1 , wherein the pinion gear has a constant angular velocity.

4. The image forming device as in claim 1 , wherein the pinion gear is connected to a drive motor by a drive shaft.

5. The image forming device as in claim 4 , wherein runout of the pinion gear is due to the drive shaft not exactly in line with the main axis of the pinion gear.

6. The image forming device as in claim 1 , wherein a number of gear teeth on the imaging cylinder gear is an integer multiple of the number of gear teeth on the pinion gear.

Assignees

• Eastman Kodak Co

Inventors

• Young Timothy John

Classifications

• G03G15/757 Primary

  Drive mechanisms for photosensitive medium, e.g. gears · CPC title

• G03G2215/0158

  Colour registration · CPC title

• G03G15/01

  for producing multicoloured copies · CPC title

• G03G2215/0141

  the linear arrangement being horizontal · CPC title

• G03G2215/00075

  the characteristic being its speed · CPC title