Improvements in Locking Devices for Printing Plates.
Year: 1890

page_text: Date of Application, 16th May, 1890-Accepted, 21st June, 1890
COMPLETE SPECIFICATION.
Improvements in Locking Devices for Printing Plates.
!, MAX SCHWERTFÜHRER of Böblingerstrasse No. 9, Stuttgart, in the Empire of
Germany, Manufacturer, do hereby declare the nature of this invention and in what
manner the same is to be performed, to be particularly described and ascertained in
and by the following statement :-
This invention relates to locking devices for printing plates and has for its purpose
to substitute for the adjusting facets hitherto employed in printing, which hold fast
the printing plate by means of screws, a contrivance allowing, through a single slight
knock on an adjusting pin with head, the facet to be drawn fast on the printing plate
and the latter on the base. The loosening of the facet is likewise effected in a rapid
manner by the aid of a hook key.
Reference being had to the accompanying drawing, in which like letters indicate
like or analogous parts throughout the different views.
Figs. 1 to 4 illustrate the improved adjustable facet and
Figs. 5 and 6 show the mode of its application.
The facet is rigidly secured to a casing H, the lower bottom of which is conical
towards its higher bottom on the opposite side. Within the said casing or box H,
which is open on the sides, a wedge K slightly broader than the bottom is displaceable
on the latter. Said wedge is pressed laterally with its surfaces K' against the
inclined surfaces of the trapezoidal slots a of the base plate F as soon as the wedge K
is moved forward on the lower inclined bottom of the casing H, which is effected by
pressure or knock on the head of the adjusting pin s integral with the wedge K and
projecting through the front side of the casing H.
The improved device is worked as follows:-
On the wedge K being driven forward on the bottom of the casing H its two lateral
surfaces K¹ come in contact with the inclined surfaces of the slot a of the base plate
and, during the further progress of the wedge K on the inclined bottom of the box H,
press the latter downward. Consequently the facet fis pressed against the bevelled
surfaces of the printing plate D as shown in fig. 6, and the latter is drawn fast on to
the base plate. The casing H, wedge K with pin s lie completely within the slots a
below the upper surface of the base plate, from which now projects the facet f.
The improved locking contrivance is undone by means of a hook-shaped key adapted
to seize the head of the pins s and draw back the wedge K.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim, is:
A locking device for printing plates consisting of a casing or box H guided in the
slots of the base plate and open at the sides, the lower portion of the bottom of said
casing ascending conically toward the upper portion, and a wedge K displaceable on
the lower bottom of said casing and provided with a pin s, said wedge being adapted,
when shifted forward, to press with its inclined lateral surfaces K' on the lower
bottom of the casing against the inclined sides of the slots a of the base plate F,
whereby the casing and the facet f secured thereto are drawn down on the printing
plate D and the latter is locked fast on the base plate F, substantially as illustrated
and described,
Dated this 15th day of May 1890.
MAX
SCHWERTFÜHRER.
By Huelser & Co.,
142, Fleet Street, London, Attorneys.