Improvements in Oyster Openers.
Year: 1892

page_text: Date of Application, 12th Nov., 1892
Complete Specification Left, 12th Aug., 1893-Accepted, 16th Sept., 1893
PROVISIONAL SPECIFICATION.
Improvements in Oyster Openers.
I ROBERT LETHBRIDGE TAPSCOTT of 62 Croxteth Road, Liverpool in the
County of Lancaster, Civil Engineer do hereby declare the nature of this invention
to be as follows:-
Improvements in oyster openers consisting of a penetrator with a knife edge held
in position by four rollers on one side, and a toothed wheel on the other. The
toothed wheel working in a rack attached to the penetrator. Shafts carry the
rollers and toothed wheel and are set in side frames. The toothed wheel is revolved
by a handle fixed on the end of the shaft. A cover is provided to hold the oyster
in place when the penetrator is applied, and has a handle at one end and at the
other is attached to supports fixed to the base of the machine. The penetrator is
shown on the drawings vertical but in some machines the side frames will be so
designed that in some it will be inclined in others horizontal.
On the accompanying drawings an arrangement of the machine is shewn.
Figure 1, shews a side view.
Figure 2, shews an end view.
Figure 3, shews a plan.
The different parts are denoted by the following letters,-Base plate f, side
frames u, penetrator k, rack on penetrator r, rollers guiding penetrator g toothed
wheel working in rack p, shafts s, turning wheel w, handle on turning wheel h,
blocks for holding shafts in place j, cover for holding oyster in place c, oyster o,
projection of cover d, supports for cover b, handle of cover l.
Dated this Eleventh day of November 1892.
R. LETHBRIDGE TAPSCOTT.
COMPLETE SPECIFICATION.
Improvements in Oyster Openers.
I, ROBERT LETHBRIDGE TAPSCOTT of 62 Croxteth Road, Liverpool in the
County of Lancaster, Civil Engineer do hereby declare the nature of this inven-
tion and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement:-
The object of my invention is to provide means whereby oysters may be opened.
For this purpose I provide a steel blade held in place by four rollers on one side
and on the other having a rack geared to a pinion which is set on the same shaft as
a handle by which it is worked. The shafts carrying the rollers and pinion are
supported by side frames. The oyster is kept in place by a cover working on a
hinge at one end and having a handle at the other. The side frames carrying the
shafts and the uprights for the cover hinge are fixed to a bed plate.
The drawings left with the Provisional Specification shew: —
Figure 3-a plan.
The different parts are denoted by the following letters :-Base plate f, side
rames u, penetrator k, rack on penetrator r, rollers guiding penetrator g, toothed
wheel working in rack p, shafts, turning wheel w, handle on turning wheel h,
locks for holding shafts in place j, cover for holding oyster in place c, oyster o,
rojection of cover d, supports for cover b, handle of cover l.
In carrying my invention into effect the oyster is placed so that the point of the

page_text: penetrator is brought into contact with, and severs the muscle holding the two
shells together. The oyster o may be placed so that the cover c shall prevent it
from slipping while the penetrator & is forced between the shells, at their thick end,
by turning the handle h, which being on the same shaft revolves the pinion p,
working in the rack thus forcing the blade down between the shells of the oyster
and through the muscle holding them together; with some oysters the cover c will
only press their thin end against the bed plate so as to raise the thick end towards
a vertical position, while with other oysters the penetrator will have to be forced
between the shells when the oyster is in nearly a flat position, with some oysters it
may be necessary to place them in a vertical position without the aid of the cover c,
when the penetrator would be pressed between the shells sufficiently to keep the
oyster upright without any support, so that the penetrator can be forced directly
between them.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
The application of the mechanical appliances substantially as and for the purpose
herein described and shewn upon the drawings.
Dated this Eleventh day of August 1893.
R. LETHBRIDGE TAPSCOTT.