Improvements in Single Trigger Double Barrel Fire Arms.
Year: 1896

page_text: Date of Application, 1st Dec., 1896-Accepted, 30th Jan., 1897
COMPLETE SPECIFICATION.
[Communicated from abroad by FRANK DE WOLF GRANGER, of No. 39
West 26th Street, in the City, County, and State of New York, United
States of America.]
Improvements in Single Trigger Double Barrel Fire Arms.
I, WILLIAM HENRY BECK of 115 Cannon Street in the City of London
Chartered Patent Agent 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 :-
My invention relates to single trigger locks for fire arms and especially for
double barreled shot guns, and has for its object to provide a new mechanism
through which a single trigger may be employed to fire either of a plurality of
barrels, and which is characterized by simplicity of construction and directness and
accuracy in operation. With such mechanism I may and preferably do combine and
employ devices whereby jar-off, that is to say the unintentional discharge of the
second barrel when the first is fired, is effectually prevented.
With such objects in view the invention consists in the parts and combinations
thereof hereinafter set forth and claimed.
In order to make the invention more clearly understood I have shown in the
accompanying drawings meaus for carrying it into practical effect without limiting
it in its useful applications, to the particular constructions which, for the sake of
illustration, I have delineated.
In said drawings:-
Figure 1 is a side view, partly in section, of a gun lock embodying my
invention.
Figure 2 is a plan view, partly in section, of the same.
Figure 3 is a plan view of the sear-plate on a larger scale.
Figures 4 to 7 are side views of the principal parts of the mechanism, showing it.
in different positions.
Figures 8 and 9 are plan and front views of a means for preventing jar-off.
Figure 1. is a plan view of the indicator actuating means, showing it in a different
position from that illustrated in Figure 3.
Figure 11 is a side view of the same.
Figure 12 is a side view of the ratchet and actuating pawl.
Referring to the drawings, in which is illustrated only so much of a gun as is
necessary to an understanding of my invention, 1 indicates the breech or frame
containing the hammers, their actuating springs and cocking mechanism, of any
usual or improved character, not necessary to be further described. The sears by
which the hammers are held cocked in a well known mauner and by the movement
of which the hammers may be released and the gun discharged, are shown at 3,
pivoted within the frame on a transverse pin or pins 4. 5 is the lock plate
adapted to be attached to the frame and carrying the trigger 6 and sear-operating
mecbanism hereinafter described. 8 is the bridge attached to or formed with the
lock plate and connected with the frame by a screw 9. The trigger 6 is pivoted
at 10 in a bracket 11 attached to the lock plate, and is controlled by a spring 12
in the usual manner. The sear operating plate or device is shown at 13. It is

page_text: movably mounted on the trigger, and the plate and rear ends of the sears are so
shaped relative to each other that when the plate is in one position the movement
of the trigger will cause the plate to engage one sear, and when it is in another
position it will be caused to engage another sear. Various shapes of the sears and
plate will effect this result. I prefer, but do not limit myself to, that shown, in
which the sears are formed with inwardly extending arms 14, 15 and the plate with
lateral projections 16, 17. The movement of the sear-plate is most conveniently a
direct longitudinal reciprocation, to which end it is confined upon the trigger by
a guide screw or screws 18 passing through a slot 19 in the plate and is further
guided by flanges 22 on the trigger. The plate 13 is normally pressed in one
direction, for instance backward, by spring 21 contained in the trigger and
engaging a projection 20 on the plate, (Fig. 4).
In the other direction the plate may be actuated by any suitable device, but my
invention comprises a new means for this purpose. 23 is a star or toothed wheel,
mounted on an axis 24" in ears 25" formed on the trigger and situated in proximity
to the plate 13. The teeth of the wheel 23 are shaped in any desired manner to
engage and thrust forward the plate 13 into the position shown in Fig. 4, and are
so placed that when a tooth is not opposite or in engagement with the plate the
latter is received between the teeth as it is pressed backward by the spring 21, and
thus permitted to assume its other position, seen in Fig. 7. The wheel may engage
the end of the plate 13 directly, but preferably engages a tooth 13ª thereon. The
wheel 23 may be actuated in any convenient manner, which in the construction
shown is effected by a fixed pawl or pawls acting on the wheel as the latter is
moved bodily by the oscillation of the trigger. I prefer, instead of arranging the
pawl to act directly on the toothed wheel, to form or attach a special ratchet
wheel 24 with or to the toothed wheel or its axis, with the teeth of which ratchet
such pawl may engage. The pawl is shown at 25 mounted on the lock plate and
controlled by a spring 26, (Fig. 12). When the trigger is pulled one of the
projections 16, 17 will be under and operate its sear. As the wheel 23 is at the
same time carried bodily upwards relative to the pawl 25 the latter will take a
new tooth on the ratchet, and as the trigger is returned to place by the spring 12,
will turn the ratchet and toothed wheel one space and change the position of the
sear-plate. The ratchet is caught and held in place, so that it will not turn while
the trigger is being pulled, by a retaining pawl or dog 26" of any suitable kind.
It being necessary to provide means for actuating the sear-plate 13 independently
of the trigger, so as to allow the same sear to be successively operated and the
same barrel to be successively discharged, I have adapted the pawl 25 to perform
this function by arranging it to be moved relative to the ratchet 24. To this end
the lower portion of the pawl is constructed as a slide 27 movable inward and
outward in a bearing 28 in or on the lock plate and having an external handle or
button 29 by which it may be operated (Fig. 12). This slide is controlled and
normally pressed downward or outward by a spring 30). The upper portion of the
pawl, or pawl proper, is pivoted at 31 to said slide and is pressed towards the ratchet
by the spring 26. By pressing upward on the button 29 the ratchet and toothed
wheel will be moved one space and the sear-plate shifted from that position in which
it will discharge the right barrel to the position in which it will discharge the
left, or vice versa.
While an indicating device, to show which barrel the parts are in position to
fire, is not necessary to the use of the invention thus far described, it is convenient
and I have devised such an indicator especially adapted for co-operation with my
new sear-plate. 33 is a cam surface arranged to move or to be moved with or by
the sear-plate 13, upon which surface rests an indicator-pin 34 mounted to slide
vertically in the gun, the upper end of which pin projects from or may be visible
above the breech and which is pressed downward by a spring 35. When this pin
is most elevated by the position of the cam surface 33, and accompanying position
of the sear-plate, it will show that the parts are in place to fire a certain barrel,
say the left; and when, by a change of position of the sear-plate and cam surface 33,

page_text: the spring 35 is allowed to depress the indicator-pin, the latter will show that the
right barrel is about to be discharged. So long as the change of position of the
said cam-surface accompanies that of the sear-plate the particular means for
actuating the former are not of the essence of my invention which includes any
suitable means for that purpose. In the construction illustrated the cam-surface 33
is formed on a lever 36 pivoted at 37 on the lock plate and having an arm 38
which bears against the sear-plate 13 and is pressed against the same by the
downward pressure of the indicator-pin on the cam-surface. The forward movement
of the sear-plate thus elevates the indicator-pin above the breech, while its rearward
movement permits it to be retracted within the same.
In the use of single trigger guns a practical difficulty has been met with in the
so called "jar-off" (unintentional discharge) of the second barrel upon the firing
of the first. The cause of jar-off has not been fully understood. According to my
observation and experiment it appears that upon the discharge of the first barrel
the recoil of the gun will move the trigger backward from the finger and relieve
the trigger of the finger pressure, whereupon the trigger will return to its normal
position, at the same time shifting the parts into position for the discharge of the
second barrel. Following this first recoil is a secondary recoil or reaction of the
gun forward from the shoulder which, before the finger can be removed from
the trigger, will bring a second and hard pressure and pull of the finger upon the
trigger sufficient to cause a secondary movement of the same and the discharge of
the second barrel. In practice the above series of movements or operations are
involuntary and so rapid that the reports of the two barrels are almost simultaneous.
This further feature of my invention consists in means whereby the secondary
movement of the trigger will be without effect or will only serve to complete that
change of position of the parts which is a necessary preliminary to the firing of the
second barrel, leaving for a further trigger movement the actual discharge of such
barrel. This feature of invention consists in means whereby the trigger or toothed
wheel or sear-actuating device is or are prevented either from moving sufficiently
far in discharging the gun for the return of the trigger at the time of the first
recoil to effect the aforesaid change in the position of the parts, or to prevent any
return of the trigger until after the secondary pull of the same.
Referring to the drawings, and especially in Figs. 4 to 9, 39 is a projection,
hook or stop formed with or attached to and carried by the trigger. 40 is a
co-operating projection or dog mounted on the lock plate, in a bearing bracket 41
or otherwise and situated in the path which the hook 39 follows when the trigger
is pulled. One or both of said projections or stops is or are movable so that as
the trigger is pulled one may pass the other. For instance, the dog 40 may slide
in the bearing 41, in which it is held and guided by a pin 42 fixed in the bearing
and passing through a slot 43 in the dog (Fig. 8), being normally pressed towards
the hook 35 by a spring 44. One or both of said engaging parts is or are formed
with a beveled surface or surfaces 45 so that as the trigger rises the movable part
(in this instance the dog 40) may be thrust out of the path of the other part by a
cam action. The dog is arranged at such height above the hook that just before
or as the trigger has moved far enough to discharge one barrel the hook will have
pressed the dog and the latter will have been thrust under it by the spring 44
(Fig. 5). The trigger will by this means be held from return or downward
movement as the recoil takes place and consequently the pawl 25 cannot shift the
toothed wheel or sear-plate. When the forward reaction succeeding the recoil
occurs the secondary pressure of the finger on the trigger gives the latter a further
upward movement which now causes the pawl 25 to take a new notch on the ratchet
so that when the trigger is finally released and the toothed wheel descends the
periphery of the ratchet will be arrested by the pawl and a turn of one step
effected. In order that the hook 39 may now repass the dog 40 the former is made
with an outer incline or bevel 45 which is carried above the dog by the complete
movement of the trigger (Fig. 9). This allows the dog to be thrust forward by
the spring 44 under the incline 45. When the trigger now descends said incline

page_text: will engage the dog and throw it out of line with the hook 39 (shown in dotted
lines in Fig. 8) allowing the latter to pass below the dog to its normal position.
When the dog is thrown out as above described it turns freely on the pin 42 and
the spring 44 serves not only to slide the dog forward but to return its forward end
inwards into line with and above the hook.
In giving the trigger sufficient movement to carry the incline 45 above the
dog 40 it may be necessary to guard against the pawl 25 taking more than one
tooth on the ratchet. This may be done by providing the pawl with a stop or
guard such as projection 50 (Fig. 12) on the trigger adaptel to keep the pawl out
of contact with the ratchet when the latter is elevated as much as the space
between two teeth.
I also obviate jar-off (retaining at the same time a short trigger pull), by
arranging the ratchet teeth relative to those on the toothed wheel and to the throw
of the trigger so that the ratchet must act twice against the pawl 25 in order to
shift the sear-plate. Thus on the first trigger pull, which produces the discharge,
the pawl 25 will take one notch. On the recoil the trigger will be released and
the toothed wheel turned one space. On the forward reaction the trigger will
receive its second (involuntary and unconscious) pull and the pawl 25 will take
another notch. On the final return of the trigger the toothed wheel will be
moved another space and the sear-plate completely shifted ready for firing the
second barrel.
I also obviate jar-off by making the movement of the trigger necessary for firing
materially less than the movement required to cause the pawl 25 to take a new
notch on the ratchet, so that only by the secondary pull of the trigger will the next
tooth of the ratchet be carried above the pawl. The sear-plate will consequently be
shifted only after the recoil and secondary pull, and the second barrel cannot be
unintentionally discharged.
My new lock hereinbefore described is so compact as to its mechanism that the
stock does not require to be cut away and weakened as with many other single
trigger constructions, but can be used without being practically changed from the
form in which it would be employed with ordinary double trigger locks.
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 1
elain is:
1. In a gun lock the combination with the trigger, and plurality of sears, of a
sliding scar-plate connected with the trigger, and meaus for shifting the same
connected with and operated by the movement of the trigger.
2. The combination with a trigger, and a plurality of sears, of a sliding sear-
plate on the trigger, a toothed-wheel on the trigger engaging the plate, and means
for turning the wheel.
3. The combination with a trigger, and a plurality of sears, of a sliding sear-
plate on the trigger, a toothed-wheel on the trigger engaging the plate, and a pawl
normally stationary relative to the trigger for actuating the wheel.
4. The combination with a trigger, and a plurality of sears having lateral arms,
of a sear-plate having lateral projections and sliding on the trigger, a toothed-
wheel on the trigger engaging the plate, and a pawl normally stationary relative
to the trigger for actuating the wheel.
5. The combination, with a horizontally sliding sear-plate, of an oscillating cam
surface, an indicator operated by said surface, and connections between said surface
and the sear-plate whereby the former is shifted with the latter.
6. The combination with a movable sear-plate, and an indicator, of a part having
a cam-surface and moving transversely to the indicator and engaging
the same, and
a pivoted lever connected with said part and operated by the sear-plate.
7. The combination, of a trigger, a plurality of sears, mechanism whereby the
latter are separately actuated by the trigger, a part having a cam-surface, an
indicator operated by the same, a lever oscillating transversely to the indicator

page_text: and connected with said part, and means whereby said mechanism actuates the
lever.
8. The combination of a trigger, a plurality of sears, mechanism whereby the
latter are separately actuated by the trigger, a relatively stationary pawl engaging
upon the return of the trigger a part of said mechanism carried by the trigger to
shift said mechanism from one sear to the other, and means for limiting the return
of the trigger and preventing jar-off.
9. The combination of a trigger, a plurality of sears, mechanism whereby the
latter are separately actuated by the trigger, a relatively stationary pawl engaging.
upon the return of the trigger a part of said mechanism carried by the trigger to
shift said mechanism from one sear to the other, and the dog 40 and hook 39 for
preventing the return, downward or forward movement of the trigger when the
recoil takes place.
10. The combination of a trigger, a plurality of sears, mechanism whereby the
latter are separately actuated by the trigger, a relatively stationary pawl engaging
upon the return of the trigger a part of said mechanism carried by the trigger to
shift said mechanism from one sear to the other, and a dog, stop or catch which
controls the trigger at the time of recoil and prevents the return, downward or
forward movement of the same.
11. The combination of a trigger, a plurality of sears, mechanism whereby the
latter are separately actuated by the trigger, a relatively stationary pawl engaging
upon the return of the trigger a part of said mechanism carried by the trigger to
shift said mechanism from one sear to the other, aud means for preventing jar-off
consisting of stops or catches such as a hook and a dog, one, of which is movable,
situated respectively on the trigger and fixed part of the lock, a spring controlling
the movable stop, and means for throwing out one of said stops to permit the return,.
downward cr forward movement of the trigger after a complete pull.
12. The combination with a trigger, of a hook on the same, a sliding and
oscillating dog for engaging the hook to control the trigger, a spring controlling.
the dog, and means on the trigger for throwing the dog out of line with the hook.
to permit the return of the trigger.
13. In a single trigger lock, means for preventing jar-off, consisting of the
combination of a plurality of sears, mechanism for actuating said sears upon the
backward movement or pull of the trigger, and a relatively stationary device or
pawl engaging a part of said mechanism only after the recoil of the gun, to shift
the said mechanism to another sear, substantially as set forth.
14. In a single trigger lock, means for preventing jar-off consisting of a trigger
and sears, a sear-plate adapted to be shifted from one sear to another, a toothed
wheel for shifting said plate, and a pawl arranged to take a new tooth on said wheel.
only after the recoil and on the secondary pull of the trigger.
W. H. BECK,
Applicant.