US2430334A - Stereotype plate casting - Google Patents

Description

Nov. 4, 1 947. c. A. HARLESS 2,430,334

v STEREOTYPE PLATE CASTING V Filed NOV. 16, 1943 INVEN TOR. Lkar/es fl. Harlass Patented Nov. 4, 1947 STEREOTYPE PLATE CASTING Charles Alonzo Harless, Oak Park, Ill., assignor to The Goss Printing Press Company, Chicago, 111., a corporation of Illinois Application November 16, 1943, Serial No. 510,459

1 Claim.

This invention is a machine for casting stereotype plates containing recesses in the back thereof, whereby circumferential tension may be exerted on such a plate when in position on the plate cylinder.

Objects and advantages of the invention will be set forth in part hereinafter and in part will be obvious herefrom, or may be learned by practice with the invention, the same being realized and attained by means of the instrumentalities and combinations pointed out in the appended claim.

The invention consists in the novel parts, constructions, arrangements, combinations, and improvements herein shown and described.

The accompanying drawings, referred to herein and constituting a part hereof, illustrate one embodiment of the invention, and together with the description, serve to explain the principles of the invention.

Of the drawings:

Fig. 1 is a vertical elevation of a stereotype plate casting machine embodying this invention; Fig. 2 is a section on line 22 of Fig. l; and

Fig. 3 is a perspective view of one of the die carrying bars of the present invention.

With high speed printing machines it is important that the stereotype plates be held snugly and tightly against the plate cylinders at all times. Due to the pressure between the form and plate cylinders, there is a tendency for a pressure wave to travel around the cylinder from the leading to the trailing edge, which tends to buckle the plate if both ends are fixed. Also, due to possible flow of metal due to pressure there may be a slight deformation of the plate and due to the high speed there is a tendency for the plate to loosen from the cylinder, All of the foregoing disadvantages are overcome to a substantial degree by securing the leading edge of the plate to the cylinder and by exerting a circumferential tension on the trailing edge.

The principal object of the present invention is to provide a stereotype plate casting machine with dies positionable in the casting space which serve as patterns for forming recesses in the back of the stereotype plate, these'dies being removable with the cast plate as it is stripped from the core. Another object is to provide dies which are useful in stripping the plate from the core. Still another object is to provide readily removable dies, which can be applied to existing stereotype plate casting machines of known design, with relatively slight modification of such machines, which dies form recesses in the back of the plate in the casting operation.

The present invention provides a modification of a known type of stereotype plate casting machine, in which the necessary recesses are cast in the back of a. stereotype plate, whereby circumferential tension, as above described, may be exerted on the plate when it is on the plate cylinder, by suitable devices on the plate cylinder engageable with such recesses.

An important feature of the present invention is to provide removable die carrying bars which may be readily applied to the existing cores or copes of a standard stereotype plate casting machine, whereby the desired recesses in the back of a steretoype plate are formed during the castin operation. The described bars are provided with dies projecting from the outer surface thereof, so that when the bars are in place in the cope, these dies project into the casting space and act as patterns in forming the desired recesses.

The die carrying bars extend longitudinally of the cope, adjacent the edge of the plate to be cast and are readily removable. This is accomplished preferably by providing dovetail grooves extending longitudinally of the cope, the bars being correspondingly dovetailed so that they slide longitudinally into said dovetailed grooves. When so positioned, the dies project into the casting space. The outer surfaces of the bars are of the same curvature as the outer surface of the cope and are flush with the said surface.

After the casting operation, the cast plate is removed together with the die carrying bars, by pulling the plate off the cope by means of handles carried by the bars. After the plate is off the cope, the bars may be readily removed from the plate.

It will be understood that the foregoing general description and the following detailed description as well are exemplary and explanatory of the invention but are not restrictive thereof.

Referring now to the preferred embodiment of the invention illustrated by way of example in the accompanying drawings, a stereotype plate casting machin of the type shown in the patent to Foster No. 2,100,003 dated November 23, 1937, is illustrated. Thi machine comprises a base 2, a pair of standards 4 supporting a plate 6 on which is mounted a core or cope 8. Cooperating with cope 8 is the usual cover composed of two parts IE3 and I2 hinged together by the hinges M. A parting strip I6 is positioned between the ends of the matrix is and a marginal bar 20 is positioned to block off the casting space 22 for the plate. The two parts of th cover are locked 3 together by the usual locking mechanism 24 and the cope is swung to and from casting and plate removing positions by the handle 26 and cooperating parts. All of the foregoing structure is known and shown for example in the Foster Patent No. 2,100,003.

Coming now to the subject matter of the present invention, the core 8 is provided adjacent each edge of the plate to be cast with longitudinally extending, dovetailed grooves 30, these grooves being tapered slightly from their upper to their lower edges. correspondingly dovetailed bars 32 adapted to fit into the dovetailed grooves 30 are provided, these bars also being correspondingly tapered toward their lower ends. The outer surfaces 34 of the bars 32 have the same curvature as the outer surface of the cope 8 so that when the bars are positioned in the dovetailed recesses 30', the outer surfaces 34 are flush with the outer surface of the cope. The lower ends 35 of the bars are accurately finished, to fit into accurately formed seats.

The bars 32 are provided with l-u'gs or dies 36, preferably hook shaped or of the desired shape of the recess to be formed in the-stereotype plate. It will be evident from the consideration of Fig. 2 that when the bars are positioned in their recesses the dies 36 will extend into the casting 'space 22 and s form thedesired recesses inthe back of the stereotype plate.

After the plate has been cast the cover is opened, and the plate is stripped from the cope by means of the handles 33 on thebar 32, the plate and the bars coming off together, by reason of the dies 36 being embedded in the cast plate at this stage. After the plate is free from the cope, the bars may readily be removed from the plate. The bars are then put back into their grooves 30 for the next casting operation.

While the invention has been shown in connection with the casting of a cylindrical stereotype plate, it is evident that it isequally applicable to the casting of a semi cylindrical plate.

The die carrying bars of the present invention are simple in construction and operation A machine for casting stereotyp plates having hook or similarly shaped recesses in the backs thereof adjacent the leading and trailing edges Which recesses are adapted to be engaged by devices for exerting circumferential tension on the plates when in position on a plate cylinder of a printing press, said machin comprising a core, ajacket completely surrounding the core and in spaced relationship thereto to provide a cylindrical casting space with an open end, a margin bar extending across said casting space throughout the length of the core to provide separated and spaced ends of a stereotype plate cast in the casting space, said core having a pair of longitudinally extending recesses each having a closed "end and an open end said recesses being positioned-one on either side of said margin bar and substantially parallel and adjacent thereto, and a bar slidable in each said recess adapted to abut the core at the closed ends of said recesses and extending beyond the end of the core when so abutting to be grasped by the hands of the operator, said bars having hook shaped die portions on the outer face thereof extending into the casting space when the bars are in the recesses to form the recesses in the cast plates and engaging the finished cast plate in a manner to cause the plate to be removed from the machine when the bars are pulled longitudinally away from the open end of the casting space.

CHARLES ALONZO HARLESS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,896,372 Rieser Feb. 7, 1933 2,360,011 Po'pp Oct. 10, 1944 2,366,475 Bartholomew Jan. 2, 1945 2,100,003 Foster Nov. '23, 193'? 2,110,154 Huck Mar, 8, 1938 1,877,535 Rosener Sept. 13, 1932 595,825 Uebelacker Dec. 21, 1897 799,048 Head Sept. 12, 1905 1,950,633 Schmeller Mar. 13, 1934 941,79 Miller NOV. 30, 1909 388,933 Topham s Sept. 4, 1888 2,124,998 Beckmann July 26, '1938 1;449;085 Brand Mar. 20, 1923

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