Patent GB-190305669-A (GB)
Title: Improvements relating to Quick Firing Guns
Inventor: DAWSON ARTHUR TREVOR
Filed: 1903-03-11
Granted: 1904-01-21
Abstract: 5669. Dawson, A. T., and Silverman, L. March 11. Quick-firing guns; ordnance breech mechanism ; mountings; loading - appliances.-Relates to improvements in automatic quick-firing guns of the kind described in Specification No. 5873, A.D. 1900. Fig. 3 is a sectional side elevation. The verticallysliding breech-block B is operated by the arm B<1> on a shaft B<2> which is turned in one direction as the gun recoils by the pawl a<1>, as shown in Figs. 5 and 6, and turned in the reverse direction by a spring in the casing B<3>. In order to avoid the risk of the empty cartridge case striking the fresh cartridge, the case is extracted during the recoil and the fresh cartridge introduced during the forward movement, this being retarded near the end by tapering the end of the prolongation n<2> of the buffer piston n<3> fitting in the cavity n<1> at the end of the brake cylinder N, as shown in Fig. 4 ; the carrier I is prevented from descending until the barrel is near the firing position by the lug Ix resting upon the barrel. The carrier I is provided with a spring pawl i to prevent the cartridge from being displaced ; the cartridge is slightly pushed forward in the carrier as it descends by the lever I<4> pivoted on the end of the stationary crank I<2>, instead of by a curved surface as described in Specification No, 15,639, A.D. 1899, The hinged catch of a pawl M<2> of the spring loading piston M, shown in Fig. 16, is pressed up against the lug L<1> with which it should engage when in the cocked position, by forming the hinge pin m of the catch M<2> with a recess having an inclined surface as shown in Fig. 17. A fiat-ended projection m<2> on the end of disc, pressed forward by the spring M', bears against the inclined surface of the recess, and thus the catch M<2> is constantly pressed upwards, its downward motion being also restricted by the stop L<2>. In some cases the hopper and cartridgecarrier are formed in a single composite piece, the hopper having a rearwardly-projecting lug, which carries the hinge pin on which the carrier is mounted. Fig. 18 shows the connection between the shoulder-piece K and the stem L by means of a cup-shaped piece K<1> receiving the outer end of the piston spring M' and entering the socketed end L<3> of the stem L. The cup-shaped piece K<1> is pressed forward, as far as the pin k will permit, against the spring M<1>, which thus absorbs vibration. The extractor of the kind described in Specification No. 26,382, A.D. 1901, is formed in two parts, as shown in Fig. 21, so that, should one of the toe-pieces C<2> be disengaged from the cam B<4> of the breach-actuating axle B', the other toepiece will still remain engaged until released by the flange of the cartridge striking it. The firing-pin D is contained in the cavity B<5>, of the block B closed by a plate b<1>. The firing-arm engages in a cavity d<1> of the firing-pin D, and can be disengaged by drawing back the pin and tilting it into the cavity b. The detachable nose d, Fig. 25<a>, is formed with a flange d<2> sliding in a groove in the firing-pin. The firing-mechanism is shown in Fig. 28. The trigger-plate o carries a three-armed lever having one arm o<2> engaging with the sliding plate O<4>, which engages with the tail F' of the firing-sear and is held in a forward position by the spring- controlled lever O<2>. When the trigger is pulled, the sliding plate O<4> is drawn back and actuates the sear ; the engagement of the hooked arm of the lever o<2> with the stop O<6> then releases the plate O<4>, which returns to its first position. The trigger can be made immovable by means of a rotary grooved pin O<7> provided with a suitable finger-piece, which engages with a stop O<8> on the trigger-plate. By means of the finger-piece, the pin O<7> may be turned so as not to engage the stop O<8>. Figs. 30 and 31 show another form of trigger mechanism which can be put at "safe," "single shots," or " auto-firing." A rotary pin O<11> is placed under the trigger-plate, which is formed with a cylindrical recess adapted to be engaged by the pin, as shown in Fig. 30, the trigger being then locked, On turning the pin into the position of Fig. 31, it fulfils the same function as the pin O<7>. The pin may also be turned so as not to engage the trigger-plate o, when the gun is fired automatically so long as the trigger is kept pulled.