Singulator for document feeder

A feeder for document processing equipment having a singulator for feeding a single document upon demand. The feeder includes a movable gate which when in a closed position acts as a fixed guide for properly aligning a stack of documents in a magazine and which when in a released position moves out of contact with the documents to relieve the frictional force between documents. The gate is moved to its released position simultaneously with the start of the pick-off means of the singulator whereby the frictional force between the first and second document is substantially reduced at the instance the first document is picked off the stack.

What is claimed is:

1. A singulator for feeding single documents from a stack of documents, said singulator comprising:

a movable feeder gate;

means for moving said feeder gate between closed and released position, said feeder gate normally being in a closed position;

a pick-off means for picking off documents one at a time from said stack of documents, said pick-off means comprises:

roller means for engaging the first document of said stack of documents;

means for driving said roller means in a forward direction upon demand to remove said first document in contact therewith, and

means for engaging any additional documents removed with said first document to prevent movement of said any additional documents with said first document;

means for feeding said stack of documents into contact with said pick-off means and said gate when said gate is in said closed position; and

means for simultaneously moving said gate to said released position and for actuating said pick-off means whereby the compression of said stack of documents is relaxed as pick-off means removes the first document from said stack.

2. The singulator of claim 1 wherein said means for moving said feeder gate comprises:

a rotary solenoid.

3. The singulator of claim 1 including:

means to move said feeder gate to said closed position when said pick-off means is deactuated.

4. The singulator of claim 5 including:

a take-off roller adapted to engage said first document as it is fed forward by said pick-off to advance same.

5. The singulator of claim 1 wherein said means for engaging any additional documents comprises:

a roller driven in a reverse direction, adapted to engage said any additional documents removed with said first document to move said any additional documents in a direction opposite to that of said first document.

6. A document feeder comprising:

a magazine adapted to receive a stack of documents;

a movable gate positioned at the front of said magazine;

a pick-off roller aligned with said gate at said front of said magazine;

a second roller aligned with and spaced from said pick-off roller;

means for simultaneously driving said pick-off roller and said second roller in a forward direction;

a third roller normally in contact with said roller to form a nip therebetween; said third roller including a slip clutch which is adapted to slip when said third roller is in contact with said second roller or is in contact with a single document passing through said nip between said second and third rollers and to be engaged when two or more documents are in said nip;

a conveyor adapted to engage said stack of documents to move said stack forward into contact with said gate and said pick-off roller;

drive means for driving said conveyor;

stop means for stopping said drive means when the pressure of said stack of documents on said pick-off roller exceeds a predetermined pressure;

means for simultaneously (a) moving said gate out of contact with said first document and (b) actuating said pick-off means; and

sensor means to simultaneously stop (a) said pickoff and second rollers and (b) close said movable gate when said first document reaches said nip between said second and third rollers.

7. The document feeder of claim 6 wherein said sensor means comprises:

a photocell positioned to sense the leading edge of said first document as it passes through said nip between said second and third rollers.

8. The document feeder of claims 6 wherein said pick-off means further includes:

a take-off roller aligned with said third roller;

means for continuously rotating said take-off roller in a forward direction;

pinch means; and

means for moving said pinch means toward said take-off roller to form a nip therebetween when said first document is adjacent said take-off roller whereby said first document is moved forward by said take-off roller.

9. The document feeder of claim 8 wherein said pinch means comprises:

an idler roller; and

an actuator for moving said idler roller toward said take-off roller to form a nip therebetween.

10. The document feeder of claim 9 wherein said actuator comprises:

a rotary solenoid.

11. The document feeder of claim 6 wherein stop means comprises:

an arm having said pick-off roller journaled thereon, said arm being mounted for rotational movement and normally biasing pick-off roller toward said stack of documents in said magazine; and

a switch actuated by said arm wherein movement of said pick-off roller away from said stack of documents moves said switch to an off position and movement of said pick-off roller towards said stack of documents moves said switch to an on position.