Registering images on the front and on the back of a substrate using high resolution sheet measurement

Claim 3

An apparatus according to claim 1, wherein said document transport further includes a driven roller that is connected to said drive motor by a linkage.

Claim 4

An apparatus according to claim 2, wherein said encoder is operatively connected to said linkage.

Claim 5

An apparatus according to claim 1, wherein the leading edge of the substrate before receiving the first toner image is the trailing edge of the substrate before receiving the second toner image.

Claim 6

An apparatus according to claim 1, further including a fuser for fusing said first toner image onto the substrate before the substrate is inverted by said inverter.

Claim 7

An apparatus according to claim 1, wherein said controller includes a logic gate for gating said encoder pulses with said leading edge and trailing edge information.

Claim 8

An apparatus according to claim 6, wherein said controller further includes a pulse accumulator for accumulating said gated encoder pulses.

Claim 9

A marking machine, comprising: a moving photoreceptor; a charging station for substantially uniformly charging said photoreceptor; an exposure station for exposing said uniformly charged photoreceptor to produce a first latent image and a second latent image; a developer station for developing toner onto said first latent image and onto said second latent image so as to produce a first toner image and a second toner image; a transfer station for transferring said first toner image and said second toner image onto a substrate; a document transport having a drive motor controlled by a drive signal said document transport for advancing a toner receiving substrate from a substrate holder to said transfer station; an inverter for inverting the toner receiving substrate after that substrate has received said first toner image and for inserting the inverted toner receiving substrate back into the document transport to receive said second toner image; an encoder for producing a predetermined number of encoder pulses per revolution of said drive motor; a sensor for detecting a leading edge and a trailing edge of the substrate as the substrate advance through said document transport; and a controller receiving encoder pulses and receiving leading edge and trailing edge information from said sensor, said controller for determining a width of the substrate from said encoder pulses and from said leading edge and trailing edge information, said controller further for controlling said document transport by applying drive signals such that said second toner image is registered with said first toner image.

Claim 10

A marking machine, comprising: a moving photoreceptor; a charging station for substantially uniformly charging said photoreceptor; an exposure station for exposing said uniformly charged photoreceptor to produce a first latent image and a second latent image; a developer station for developing toner onto said first latent image and onto said second latent image so as to produce a first toner image and a second toner image; a transfer station for transferring said first toner image and said second toner image onto a substrate; a document transport having a drive motor controlled by a drive signal said document transport for advancing a toner receiving substrate from a substrate holder to said transfer station; an inverter for inverting the toner receiving substrate after that substrate has received said first toner image and for inserting the inverted toner receiving substrate back into the document transport to receive said second toner image; an encoder for producing a predetermined number of encoder pulses per revolution of said drive motor; a sensor for detecting a leading edge and a trailing edge of the substrate as the substrate advance through said document transport; and a controller receiving encoder pulses and receiving leading edge and trailing edge information from said sensor, said controller for determining a width of the substrate from said encoder pulses and from said leading edge and trailing edge information, said controller further for controlling said document transport by applying drive signals such that said second toner image is registered with said first toner image.

Claim 11

A marking machine according to claim 8, wherein said document transport further includes a driven roller that is connected to said drive motor by a linkage.

Claim 12

A marking machine according to claim 9, wherein said encoder is operatively connected to said linkage.

Claim 13

A marking machine according to claim 8, wherein the leading edge of the substrate before receiving the first toner image is the trailing edge of the substrate before receiving the second toner image.

Claim 14

A marking machine according to claim 8, further including a fuser for fusing said first toner image onto the substrate before the substrate is inverted by said inverter.

Claim 15

A marking machine according to claim 8, wherein said controller includes a logic gate for gating said encoder pulses with said leading edge and trailing edge information.

Claim 16

A marking machine according to claim 13, wherein said controller further includes a pulse accumulator for accumulating said gated encoder pulses.

Claim 19

The method according to claim 15, further including a step of fusing said first toner image onto the substrate before the inverting said substrate.

Claim 20

The method according to claim 16, wherein the step of determining the width of said substrate is performed after fusing.

Claim 21

The method according to claim 15, wherein the step of producing a first toner image and a second toner image on a photoreceptor includes the step of scanning a first image and a second image.