US1096494A - Method of making printing devices. - Google Patents

Description

J. S. DUNCAN.

METHOD OF MAKING PRINTING DEVIOES.

APPLICATION TILED MAR.23,1912.

Patented May 12, 1914.

UNITED STATES PATENT OFFICE.

JOSEPHS. DUNCAN, OF CHICAGO, ILLINOIS. ASSIGNOR T0 ADDRESSOGRAPH COMPANY,

OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

METHOD OF MAKING PRINTING DEVICES.

Patented May 12, 1914.

Application filed March 23, 1912. Serial No. 685,813.

'1 '0 all whom it may concern:

Be it known that I, Josnrn S. DUNCAN, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Methods of Making Printing Devices,'of which the following is a specification. I

My present invention relates to the method of making printing devices and has for its principal object the production of a printing device having flat faced sharply defined printing characters Whereby even, uniform and sharply defined impressions may be made upon thepaper.

For the purpose of facilitating the explanation of my invention I have disclosed on the accompanying drawings fragmentary views of a printingdevice showing completed printing characters and the method of producing the same.

Referring to the drawings-Figure 1 is a fragmentary sectional view of a printing device having printing characters stamped thereon and a means for finishing the said characters; Fig. 2 is a plan view of the printing device shown in Fig. 1; Fig. 3 is a fragmentary perspective view ofa stamped up printing character before it is rolled; and Fig. i is a perspective view of a printing character after the same has been subjected to the finishing or rolling operation.

Printing characters have been formed on metal blanks or sheets long prior to my present invention by stamping or striking up the characters from the body of the blank and various machines equipped with punches and dies for performing this operation have. been devised. The printing surfaces of thecharacters formed in this way, however, are more or less curved, particularly near the edges, and consequently do not produce clear and sharply defined impressions. Further more, as the result of unavoidable inaccuracies in the punches and dies and the machines for operating the. same, some of the characters will be stamped up a greater distance ,than others so that the printing surfaces of various characters lie in different planes, with the result that a heavier impression is produced by some of the characters than by others.

My present invention aims to reduce the printing surfaces of all of the printing characters on a plate or blank to a common plane and to provide each of the characters with a flat printing surface having sharply defined edges so that clear, uniform and sharply defined impressions will be produced by every character on the device.

On the drawings reference character 5 designates, generally, a printing device which may be a metal blank sheet or frame of any preferred contour and construction, the contour and construction of the device or blank being immaterial so far as my present invention is concerned. In the production of printing characters on this device or blank the metal is subjected to the action of punches and dies in the customary manner to produce the printing characters desired in relief on one side thereof. In the present instance the struck up characters produced by the punching or stamping operation are designated by reference numeral 6. The upper or printing surfaces of the struck up characters are more or less curved as will be apparent from the drawings and the curvature is particularly noticeable near the edges of the surfaces where the metal merges from the printing surfaces into the body of the characters. Owing to the unavoidable irregularities and imperfections in the punches-and dies and in the operation of the machines the printing surfaces of the various characters will not all be struck up the same distance from the body of the blank and as a result uniformly clear impressions can not be made by all of the characters. In order to reduce the printing surfaces of all of the characters'on the blank to a common plane without removing any of the metal and in order to produce flat printing surfaces having sharply defined edges I subject the blank with the letters struck up therefrom to a rolling operation.

One practical method of producing the desired result is illustrated in a conventional manner in Fig. l where the plate is shown as positioned upon a bed 7 beneath a roller 8 mounted with its periphery a predetermined distance from the adjacent surface of the bed. The bed is preferably mounted to move relatively to the roller but, obviously, the'roller might be moved relatively to the bed. In the present instance the bed is movably mounted and as the bed travels in the direction of the arrow the printing characters stamped up on the metal blank will be subjected successively to the action of the roller and the upper'or printing surfaces of the characters will be depressed into a common plane and flattenedto produce sharply defined contours without weakening the structure or removing any of the metal. Obviously the bed might be held stationary, if preferred, and the roller made to travel relatively to the bed.

lhe characters which have or subjected to therolling operation are indicated on the drawings by reference numeral 9 and, from inspection of Figs. 1 and 2, the difference in the characters before and after being snbjected'to the rolling operation will be readily apparent. Before the rolling operation the characters have more or less curved printing surfaces of irregular contour disposed in various planes while the rolled or finished characters have flat sharply defined printing surfaces all disposed in a common plane.

While I have shown on the drawings a series of capital Hs, it will be understood been worked iamaaea I that this letter'was selected merely for purposes'of illustration and that the entire alphabet in upper and lower case letters as Wellas numerals and other printing characters c'an be accuratelyproduced bymy 3 improved method: a It will also be understood that my invention is not restricted to the illustrative disclosure herein made but is capable of considerable variation without departing from the spirit of the invention or sacrificing any of the material advantages thereof.

' I claim:

The method of producing printing characters consisting in striking up from a metal sheet a plurality of raised printing characters and rolling the tops of the characters without removing any of the material from the printing characters to produce flat sharply defined printing surfaces all disposed in a common plane.

JOSEPH S. DUNCAN. Witnesses WM. 0. BELT, IRA J. WILSON.

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