Patent GB-729651-A (GB)
Title: Improvements in or relating to industrial stud driving tool
IPC: B25C1/12
Filed: 1952-04-22
Abstract: 729,651. Explosively-operated tool for firing studs and the like. REMINGTON ARMS CO., Inc. April 22, 1952 [May 8, 1951], No. 10137/52. Class 119. Explosively-operated device for firing projectile-like studs into masonry comprises a barrel 1 screwed into a frame 2 on which is hinged a breech block 3, a breech lock 5 securing the block 3 when it is aligned with the barrel. Swinging of the breech block is limited by movement of a stop pin 7 in an arcuate slot 6 in the frame. A cover 8 houses parts of an automatic safety device and a cartridge ejecting system while a similar housing 9 enclosing the firing mechanism and the rest of the safety mechanism is integral with a handle 10. The spring-pressed firing pin 11 aligned with the rim of a cartridge in the chamber 12 is supported in a bushing 13 in the rear wall of the housing and in a bore 14 in the breech block 3. A sear 17 is provided with a flange 19 engaging a flange 16 on the firing pin to hold the pin in the cocked position and has an arm 20 contacting a cam surface 21 on a slidable trigger bar 22, so that when the trigger is pulled rearwardly by means of a finger piece 23 the cam 21 urges the sear to the release position. A safety plunger 25, Fig. 7, has a flange 26 engaging a cam 28 provided with a roughened surface opposed to a similar surface on the trigger bar. By depressing the plunger the cam is rotated to move the roughened surfaces out of engagement so that the trigger may be operated. On release of the plunger the surfaces engage and any rearward movement of the trigger rotates the cam into closer engagement, thus locking the trigger The sear is held by a spring-pressed lock 31 moved rearwardly to release the sear by means of a finger 32 on a tube 33 within the cover 8. When the breech is closed and locked as ir Fig. 1, holes 34, 35 are aligned, so that the finger 32 can move to engage the sear lock. When the breech is not locked the holes are out of alignment and the sear lock cannot be moved. The tube 33 carrying the finger 32 is moved when the device is pressed against a surface so that an extension 36 of the tube slides telescopically on the barrel against the action of a spring 37. On firing of a cartridge the sear cannot re-engage the flange 16 under the influence of its spring 39 until the breech is opened by means of a slide 40. The slide 40 movable in a groove in the breech block is slotted at 41 to straddle the firing pin forwardly of a cocking flange 42 and is urged by a spring 44 to the position shown in Fig. 3, when a cam pin 45 extending into a notch 46 in the frame latches breech block and frame in alignment. By forcing the slide inwardly, the cam pin is disengaged from the notch and the frame can be turned relatively to the block. Simultaneously a cam surface 47 on the slide engages the flange 42 to move the firing pin rearwardly out of the path of the frame and the pin 45 rides on the periphery of the frame, thus forcing the slide to the right and wedging the firing pin back beyond the cocked position so that the sear re-engages the flange 16. Further swinging of the frame exposes the breech, the pin 45 acting as a detent to hold the breech open. A cartridge ejector 48, Fig. 10, mounted in a groove in the barrel has a claw 49 extending beneath the cartridge rim, so that by rearward movement of a handle 50 the cartridge is withdrawn. The muzzle end of the barrel may be counterbored to facilitate removal of the device after firing when studs provided with a sabot as described in Specification 729,649 are used. The counterbore is in two parts, an outer flared section 57 and an inner cylindrical part 58. A conical guard 53 filled with neoprene 54 or other rubberlike material may be fitted over the extension 36. Interchangeable extensions with fitted guards to suit particular jobs may be provided. The extensions may be counterbored as at 55 to accommodate metal or other discs held in place by detents integral with a spring 56. The projectile-like studs pass through the discs which then serve as washers. The device is placed in position by aligning guide notches on the guard with guide lines on the work.