US3355829A

US3355829A - Document flattener

Info

Publication number: US3355829A
Application number: US493756A
Authority: US
Inventors: Dennis P Butterbaugh
Original assignee: International Business Machines Corp
Current assignee: International Business Machines Corp
Priority date: 1965-10-07
Filing date: 1965-10-07
Publication date: 1967-12-05
Anticipated expiration: 1984-12-05
Also published as: DE1297912B; FR1492717A; GB1139937A

Description

Dec 5, 1967 D. P. BUTTERBAUGH 3,355,829

DOCUMENT FLATTENER Filed Oct. '7, 1965 STACKER INVENTOR DENN|S P. BUTTERBAUGH @YM ATTORNEY United States Patent O 3,355,829 DOCUMENT FLATIENER Dennis P. Butterbaugh, Rochester, Minn., assignor to lluternational Business Machines Corporation, Armonk, N.Y., a corporation of New York Filed Oct. 7, 1965, Ser. No. 493,756 8 Claims. (Cl. itl- 156) ABSTRACT F THE DISCLOSURE The invention provides selectively operable pressure applying apparatus which operates with a captured air supply. A flexible diaphragm is bonded or otherwise secured around its perimeter to the edges of a flat rigid backplate preferably with a slight tension preload. The rigid backplate is provided with one or more holes which communicate with one or more flexible cups. The llexible cups are provided with an edge which is lbonded to the -backplate about the hole. The bottom of each cup is attached to a spring biased armature of an electromagnet. Current through the magnet coil holds the armature against an associated compression spring. This causes the diaphragm t-o be flat against the rigid backplate and away from `a surface plate. When the magnet is de-energized, the compression spring forces the armature to collapse the associated flexible cup. The displaced air in response to the cup being collapsed inflates the diaphragm which presses or iiattens an object such as a document against the surface plate. Atmospheric pressure aids the tension preload in returning the diaphragm to a flat deated conditioniwhen the magnets are again energized.

' This invention relates to selectively operable pressure applying apparatus and more particularly to apparatus for flattening documents against a viewing surface in a reading station during the reading period.

The invention finds particular utility in optical character reading machines where the documents are read while stationary. In such machines it is highly desirable to have all characters in the same plane for reading. However, these machines are required to process live documents which in many instances have been folded and otherwise have become crumpled from handling. Hence, it is necessary to flatten the documents against a viewing surface during the reading operation whereby substantially all characters will be in the same plane. The documents must be flattened without smudging the print thereon and at high speeds with little noise. The document flattener also functions to seal off or prevent extraneous light from entering the reading area to interfere with the optical reading light collection system.

Heretofore, it has been the practice to inflate a diaphragm with external duid pressure to press the documents against the viewing surface. In some instances, the documents have Ibeen sucked against the viewing surface by means of a vacuum, The use of external iluid pressure and vacuum sources generally require some exhaust system. This introduces a time factor `which reduces the speed of operation. This invention operates with a captured air supply. A flexible diaphragm is bonded or otherwise secured around its perimeter to the edges of a flat rigid back plate preferably with a slight tension preload. The rigid back plate is provided with one or more holes which communicate with one or more flexible cups. The flexible cup or cups are provided with an edge which is bonded to the back plate about the hole. The bottom of the cup or cups is attached to a spring biased armature of an electromagnet. Current through the magnet coil holds the armature against the associated compression spring. This 3,355,829 Patented Dec. 5, 1967 lCC causes the diaphragm to be flat against the rigid back plate and there is suicient clearance for the document to enter the reading station between the diaphragm and the viewing surface plate. With the document in place, the magnet is fle-energized. The compression spring forces the armature to collapse the flexible cup. The displaced air in response to the cup being collapsed inflates the diaphragm which presses or attens the document against the viewing surface. Atmospheric pressure aids the tension preload in returning the diaphragm to a flat, deflated condition.

Accordingly, it is a principal object of the invention to provide improved selectively operable pressure applying apparatus.

Another object of the invention is to provide selectively operable pressure applying apparatus which operates at relatively high speeds.

Still another object of the invention is to provide selectively operable pressure applying apparatus which is relatively quiet in operation.

A further object of the invention is to provide selectively operable pressure applying apparatus which operates with a captured air supply.

Yet another object of the invention is to provide selectively operable pressure applying apparatus which is relatively simple and inexpensive.

A more specific object of the invention is to provide selectively operable pressure applying apparatus for iiattening documents against a viewing surface in a -reading] station in a character recognition machine.

The foregoing and other objects, features and advantages of the invention will be apparent from the following more particular description of a preferred embodiment of the invention, as illustrated in the accompanying drawings.

In the drawings:

FIG. 1 is an exploded isometric view of apparatus embodying the invention;

FIG. 2 is a fragmentary view partially in section with the electromagnet energized and the diaphragm in its nondisplaced position;

FIG. 3 is a fragmentary view partially in section with the electromagnet de-energized and the diaphragm displaced; and,

FIG. 4 is a schematic view of a document reading machine incorporating the invention.

With reference to the drawings and particularly to FIG. l, the invention is illustrated by way of example as including apparatus for attening document 10 against viewing surface 11. Diaphragm 12, preferably made of rubber, is `bonded or otherwise secured to the face of rigid plate 13 about the perimeter thereof and preferably with a slight tension preload. Plate 13 is provided with one or more openings 14 which for the purpose of providing a continuous level surface are provided with a concentric recess 15 for receiving the annular lip 15 of flexible cup 17. The lip 16 is bonded or otherwise suitably secured within the recess 15. The exible cup l17 includes bellowslike or serrated sections 18 for permitting expansion and contraction of the cup 17. The bottom 19 of cup 17 is bonded or secured to a disc-like armature 20 of electromagnet 21. Electromagnet 21 includes a U-shaped yoke 22 formed from a plate 23 to flank the cylindrical electric coil 2.4 through which a core 25 projects. Screw 27 threads into the core 25 to hold coil 24 in place. Compression spring 26 abuts plate 23 at one end and armature 20 at its other end to bias armature 20 away from yoke 22 and core 25.

When coil 24 of electromagnet 21 is energized, armature 20 is attracted against yoke 22 and compresses spring 26 as seen in FIG. 2. The flexible cup 17 under these conditions is expanded and the flexible diaphragm 12 lies flat against the face of plate 13. This provides sucient clearance for document to come between the flexible diaphragm 12 and the viewing plate 11. When it is desired to flatten document 10 against the viewing surface of plate 11, electromagnet 21 is de-energized. Compression spring 26 expands to move armature 20 away from yoke 22 and thereby collapse cup i7 as seen in FIG. 3. As cup 17 collapses, the air captured therewitnin is displaced and moves flexible diaphragm 12 toward plate 11 to force or flatten the document 10 thereagainst. Coil 24 can be normally energized and upon stopping document 10 in the reading station, it can be de-energized. After the document is read, coil 24 is again energized.

In FIG. 4, the invention is sho-wn as being incorporated into an optical character reading machine. Documents 10 are transported from hopper 30 to reading station 40. The documents upon entering reading station 40 are ilattened against viewing surface 11 as electromagnets Z1 are de-energized. In this particular instance, several electromagnets and associated cups are used. The documents 10 are read in the stationary, attened condition. After a document has been read, the magnets 21 are energized and the document is transported to one of two stackers 50.

From the foregoing it is seen that the invention provides selectively operable pressure-applying apparatus. Further, it is seen that this selectively operable pressure applying apparatus operates with a captured air supply. This arrangement results in a selectively operable pressure applying apparatus which is capable of high speed operation and relatively simple, inexpensive and quiet in operation.

While the invention has been particularly shown and described with reference to a preferred embodiment thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention.

What is claimed is:

1. Selectively operable pressure applying apparatus comprising:

a rigid plate having at least one aperture therein;

a exible diaphragm secured to one side of said plate to cover said aperture;

an expandable and collapsible cup closed at one end and secured at its open end to the other side of said plate about said aperture; and

means for selectively expanding and collapsing said cup whereby the air in said cup is displaced to move said diaphragm against and away from said plate, respectively.

2. The pressu-re applying apparatus of claim 1 wherein said selectively operable expanding and collapsing means comprises:

an armature attached to said cup;

a selectively operable electromagnet for attracting said armature thereto upon being energized; and

means for biasing said armature away from said electromagnet.

3. The pressure applying apparatus of claim 1 where said diaphragm is attached to said plate with a tension preload.

4. The pressure applying apparatus of claim 1 where said cup is provided with serrated walls to facilitate expanding and collapsing said cup.

5. A document tlattener comprising:

a fixed backing plate, a rigid plate spaced from said backing plate to permit a document to pass therebetween, said rigid plate having at least one aperture therein;

a flexible diaphragm secured to said rigid plate to face sa'd backing plate and cover said aperture;

an expandable and collapsible cup closed at one end and secured at its other end to said rigid plate about said aperture; and,

means for selectively expanding and collapsing said cup whereby upon expanding said cup the air therein is displaced to move said diaphragm against said rigid plate and upon being collapsed, the air therein is displaced to move said diaphragm toward said backing plate to flatten said document thereagainst.

6. The document flattener of claim 5 wherein said dia-v phragm is secured to said rigid plate with a tension preload.

7. The document flattener of claim 5 wherein said se* lectively operable expanding and collapsing means comprises:

an armature attached to the closed end of said cup;

a selectively operable electromagnet for attracting said armature thereto upon being energized to expand said cup; and,

means for biasing said armature away from said electromagnet whereby upon said electromagnet being deenergized said cup is collapsed.

8. The document flattener of claim 5 wherein said cup is provided with serrated walls to facilitate expansion and collapsion of said cup.

References Cited UNITED STATES PATENTS 8/1901 Gerlach 95-76 X 5/1933 Sherts 40-156 OTHER REFERENCES EUGENE R. CAPOZIO, Primary Examiner.

W. J. CONTRERAS, Assistant Examiner.

Claims

1. SELECTIVELY OPERABLE PRESSURE APPLYING APPARATUS COMPRISING: A RIGID PLATE HAVING AT LEAST ONE APERTURE THEREIN; A FLEXIBLE DIAPHRAGM SECURED TO ONE SIDE OF SAID PLATE TO COVER SAID APERTURE; AN EXPANDABLE AND COLLAPSIBLE CUP CLOSED AT ONE END AND SECURED AT ITS OPEN END TO THE OTHER SIDE OF SAID PLATE ABOUT SAID APERTURE; AND MEANS FOR SELECTIVELY EXPANDING AND COLLAPSING SAID