US 1555104 A
Description (OCR text may contain errors)
Sept. 29, 1925.
' C. B. CORCQRAN TYPEWRITING MACHINE Filed Nov. 2, 19215 Patented Sept. 29, 1925.
UNITED STATES PATENT OFFICE.
CORNELIUS COROORAN, DECEASED, LATE OF NEW YORK, N; Y., BY MICHAEL J'. CORCORAN, ADMINISTRATOR, OF NEW YORK, N. Y., ASSIGNOR TO UNDERWOOD TYPEWRITER COMPANY, OF NEW YORK, N. Y., A CORPORATION OF DELAWARE.
To all whom it may concern."
Be it known that CORNELIUS B. Conco- RAN, deceased, late a citizen of the United States, and late residing in the borough of Bronx, county of Bronx, city and State of New York, invented certain new and useful Improvements in Typewriting Machines, of which the following is a specification.
This invention. relates to cylindrical typewriter-platens, which usually comprise a. moderately hard rubber shell to receive the type blows, such shell having the quality of contributing to the clearness of the impressions and also possessing the quality 'of durability.
One difliculty with a rubber platen is that y it wears smooth, and then does not accept ably perform one of its functions, which is to feed the work-sheets around it. The platen usually co-operates with soft rubber feed-rolls, but, owing to the smooth surface 7 which the platen acquires, there is apt to and it is occur slipping between the platen and the work-sheet, resulting in faulty line-spacing movements of the latter.
The difiiculty is especially noticeable where many copiesare being manifolded, also found that the several thin Work-sheets will slip irregularly one upon another to an objectionableextent. As the work-sheets used for manifolding are..usually thin, and often have a glossy or slippery surface, the irregularity of line-spacing of the sheets becomes more noticeable. The platen is usually rotated very rapidly by the line-space handle, and as a result the platen starts before the pack of worksheets does; and other causes of faulty movements of the paper exist.
It is an object of the invention to reduce or eliminate this trouble in manifolding, and for this purpose the invention is in the nature of an improvement in the platen, for minimizing or eliminating the slipping of the sheets, while affording clear type-impressions.
To this end the platen comprises, in place of the usual rubber, a printing surface which consists of a microscopic or minutely corrugated metal shell, preferably brass, the corrugations preferably extending in closely and evenly spaced or milled straight lines longitudinally of the platen, in order to secure maximum traction on the sheets. To
2, 1923. Serial No. 672,250.
avoid cutting the paper, brass should be used and the corrugations should be made Without sharp edges. The corrugations aid in the production of clear type-impressions when manifolding, and have thefurther effect of causing the inner work-sheets to cling to the platen, whereby relative cree ing of the platen and work-sheets is su stantially reduced or overcome. Moreover, the several sheets in the pack are caused to cling more effectively to one another, without causing the work-sheets to become smudged from the carbon-sheets.
Other features and advantages will hereinafter appear.
1 In the accompanying drawings,
Figure 1 is a front elevation of a cylindrical form of platen, partly in section, showing the platen providedwith a unigormly roughened or milled non-slip surace. I
Figure 2 is an enlarged fragment of a section ofthe platen-cylinder shell, showing the'preferred form of the improved nonslip platen surface.
A cylindrical platen 10 may comprise a shell 15, mounted on an axle 11. Usual end plates 12, having hubs 13 and screws 14-, passing through the hubs 13, may be rovided for mounting the shell 15. The shell 15 may be provided with a uniformly and microscopically or minutely roughened or milled surface 16, shown in Figure 2 as having numerous fine teeth 17 which resemble a very fine corrugation, milled longitudinally of the platen.
Variations may be resorted to within the scope of the invention, and portions of the improvements may be used without others.
Having thus described my invention, I claim:
1. A metal cylindrical platen having an impression surface formed with numerous closely-spaced, microscopic, projections to hold a pack of smoothly-finished work-sheets from slipping during feeding, and to enable the types to make clear impressions when manifoldin 2. A cylindrical brass platen having an impression surface formed with numerous closely-spaced, minute, projections to hold a pack of smoothly-finished work-sheets from slipping during feeding, and to enable the types to make clear impressions when manifolding," said projections in the form of edges running longitudinally of ;the platen.
3. A metal. cylindric'alplaten having an impression surface formed with numerous .olosely-spaced, corrugations or projections to hold a pack of smoothly-finished worksheets from slipping duringfeeding, and to enable the types to make clear impressions when manifolding,'said projections in the form of edges running longitudinally ofthe platen, said edges or teeth formed by milling the surface of the shell longitudinally.
MICHAEL J. CORCORAN, Administrator of the Estate of C'owwh'us B.