CERTAIN NEW AND USEFUL IMPROVEMENTS IN FIRE-ARMS
Year: 1855

page_text: LETTERS PATENT to Samuel Edwin Robbins, of the State of Vermont, of
the United States of America, for the Invention of "CERTAIN NEW AND
USEFUL IMPROVEMENTS IN FIRE-ARMS."-Partly a communication from
George Leonard of the coid United States
COMPLETE SPECIFICATION filed by Sanuel Edwin Robbins at the Office
of the Commissioners of Patents, with his Petition and Declaration, on
the 24th May 1855, pursuant to the 9th Section of the Patent Law
Amendment Act, 1852.
TO ALL TO WHOM THESE PRESENTS SHALL COME.
BE IT KNOWN that I, SAMUEL EDWIN ROBBINS, of the State of Vermont,
of the United States of America, do hereby declare that I have made an
Invention of "CERTAIN NEW AND USEFUL IMPROVEMENTS IN FIRE-ARMS," (part or
parts of such Invention having been communicated to me by George Leonard,
of the said United States,) and I do hereby declare that the said Invention is
fully described and represented in the following Specification, and the accom-
panying Drawings, letters, figures, and references thereof:-
Of these Drawings, Figure 1 exhibits a side view of one of my improved
repeating fire-arms; Fig. 2 is a top view of the same; Figure 3 is a central
vertical and longitudinal section of it; Figure 4 is a side view of it, showing
the lock plate or stock cover as detached, and the moveable chambered

page_text: cylinder and barrels turned down with respect to the handle or lock, and in
order to enable a person to obtain easy access to the percussion nipples,
in order to prime the same, or place caps thereon; Figure 5 is a rear view
of the chambered magazine; Figure 6 is an end view of the moveable series
of barrels; Figure 7 is a side view of the revolving hammer; Figure 8 is
a transverse section of said hammer.
In such Drawings, A denotes a chambered cylinder or magazine, it being
pierced with five or any other suitable number of bores or loading chambers 6,
arranged around in a circle, as seen in Figure 9, which is a transverse section
of such part A. The rear end of each of these loading chambers is provided
with a percussion cap or nipple C, such nipple being arranged within a
protection chamber D, as seen in the Drawings.
The said magazine A so constructed is hinged to the stock or lock case E,
as seen at F, and in such manner as to enable it to be turned down with
respect to the stock, as seen in Figure 4, and so as to permit free access to be
had to the percussion nipples. From the middle of the chambered magazine A,
and in line with its axis, a spindle G projects, and passes through a cylindrical
bore or passage F, formed through a moveable block I, in which there is a
series of bores or barrels K, K, K, the number of which corresponds to that
of the chambers in the magazine.
The front half or part of the bore H is made somewhat larger in diameter
than is the rear part of it, the same being in order to enable it to receive the
head of the screw L, which is screwed into the extreme outer end of the
spindle G. The lower part of the spindle, or that next the magazine, is pro-
vided with a male screw M, which is adapted to a corresponding female
screw N, made in the lower part of the bore II.
By so combining with the stationary magazine a moveable series of barrels,
ready access to the charge chamber may be had at any time for the purpose of
supplying the same with charges. In order to accomplish this, it will only be
necessary to unscrew the block I from the spindle G, and draw it forwards
thereon, the head of the screw L preventing it from separating therefrom. If,
the pistol be held in a vertical position, the block I being grasped in the
left hand, each charge chamber will be brought into a convenient situation to
receive its charge of powder and ball. When the block I is screwed closely
ngainst the chambered magazine, the axes of the barrels or bores should
respectively range in line with those of the charge chambers of the magazine.
now,
The upper part of the chambered cylinder A is provided with a locking
recess O, adapted to receive a catch I', which consists of a lever formed and
supported upon a fulcrum R, and within a recess c in the stock, as seen in

page_text: the Drawings. Its rear arm rests upon the upper leaf a of a V spring S, whose
lower leaf a' is supported on a rest b, or upon the bottom of the space or
recess c. From the lower leaf of said spring S a stud or pin d extends
downward, and enters one of the grooves of a cylindrical shank of a rotary
hammer T.
During the reciprocating rectilinear movements of the hammer, these
grooves, acting in conjunction with the spring stud, servo to rotate the hammer
in a direction transverse to its axis. The shank of the haminer so supported
slides and turns freely in bearings at e, f. It has arranged longitudinally on
its surface and at equal distances apart a series of straight grooves (9), corre-
sponding in number with that of the loading chambers of the magazine. Each
of these grooves terminates at its rear end in a helical groove h, which makes
an acute angle with it, and extends above and below it, and enters the groove
next above it, as seen in Figure 10, which is a developement of the
a plane surface.
grooves upon
Where each helical groove enters a straight groove, its depth is not so great
as is the straight groove at the place of intersection. The rear end of each
straight groove is also made of a depth less thau that part of the helical groove
into which it leads.
This arrangement of grooves will cause the hammer to make a partial
revolution whenever it is retracted, the spring stud passing through n helical
groove and dropping into a straight groove, through which, while the hammer
is moved forward, the stud also passes, and is received into the helical groove
at the rear end of such straight groove; one groove being deeper than its
entering groove where they join, prevents the stud from entering into the latter
while it is passing by it. The rotary hammer operates successively on the
percussion priming or caps, they being stationary relatively to it while the fire-
arm is being discharged. This rotary hammer is an important feature of my
Invention.
The upper end of the main spring U of the hammer rests in a groove i
made around and in the latter. The said main spring is provided with a
shoulder k, as seen in Figure 11 [which denotes a front view of the spring],
such shoulder also being exhibited in Figure 3. It operates in connection
with the trigger V and with a locking catch W, which is furnished with a
secondary trigger or thumb bearer 1 and a spring m, applied and arranged as
seen in Figure 3, said thumb bearer being extended through the lock case or
stock, so as to be in a convenient position to receive pressure from the thumb
while the stock is held in the hand. The fulcrum n of the trigger is within
a retracting lever X, which turns upon a fulcrum or pin o, and during the act

page_text: of cocking, the hammer is pulled backward by the middle finger of the hand
while it is grasping the pistol by its stock. While moving rearward such
lever X forces the shoulder of the trigger against the shoulder k of the
main spring, and moves said main spring back until it is seized by a locking
catch W, the hammer being in the mean time retracted by the main spring.
The trigger serves to liberate the catch W from the main spring, such
liberation when the trigger is pulled being accomplished by the upward pres-
sure of the rear arm of the trigger against the catch W, the trigger being
suitably formed for such purpose, or as exhibited in top view in Figure 12.
After each discharge, the forward motion of the trigger and retracting lever
is effected by the pressure of a spring p; whenever it may be desirable to let
down the hammer without discharging the pistol or fire-arm, it can be accom-
plished by pressing with the thumb upon the head or bearer of the secondary
or thumb trigger 1, and easing the hammer down with the finger in the ring
of the cocking lever.
I do not claim a single stationary barrel and a rotary chambered magazine,
arranged and applied to the stationary barrel, so that each chamber may be
moved around so as to be brought into line with the bore of the barrel; but
what I do claim is, the combination of a stationary chambered magazine, or
series of barrels with a moveable series of bores or barrels, and mechanism
by which the latter may not only be connected to the former, so as to bring
the axis of its bores respectively in range of those of the magazine, but so
practically disconnected, as occasion may require, as to enable the charge
chambers of said magazine to be loaded, as specified.
And I also claim the peculiar manner of connecting tho chambered magazine
and its moveable series of barrels, viz., by means of a spindle G, screw L, or its
equivalent, the male and female screws, and a bore II, formed as above specified,
the same being applied and made to operate together, substantially as herein-
before explained.
I also claim combining the chambered magazine to the stock by such
mechanical devices as will enable the said magazine not only to be turned
down into an inclined position with respect to the stock, in manner and for
the purpose as described, but to be turned up and locked to the stock, so as to
be in a position for its nipples, or the priming thereof, to be acted upon by the
revolving hammer.
I also claim the improvement of so applying the hammer to the series of
barrels, or the loading chambers, that such hammer, while they are stationary,
may be moved around so as to strike on their primings or nipples successively,
is specified.

page_text: I also claim the application of the main trigger directly to the retracting
lever of the main spring and hammer so as to be moveable therewith, in
manner substantially as specified.
I also claim combining a rest or bearer with the spring S, the lever catch
over it, and the pin or stud below it, in order that the spring may not only
serve to operate the lever catch but the pin, as above described.
I also claim the mechanism for rotating the hamn:er during its recipro-
cating rectilinear movements or rearward motions as described; the same
consisting of the spring dog or stud, the series of straight grooves and the
series of helical grooves formed in the hammer shank, and arranged at angles
and in depths with respect to each other, so that the spring dog may operate
in them, as specified.
I also claim the combination of the secondary or thumb trigger with the
main trigger, its catch and the main spring, the same being arranged so as to
be operated by the thumb while the pistol is held in the hand, as specified.
In testimony whereof, I have hereunto set my signature and seal, this
Eleventh day of May, in the year of our Lord One thousand eight
hundred and fifty-five.
SAMUEL EDWIN ROBBINS. (LS.)