Patent GB-802883-A (GB)
Title: Improvements in or relating to the manufacture of shells for barrels
IPC: B27D1/08
Filed: 1957-04-02
Abstract: 802,883. Making barrel shells. BJARNASON, B. April 2, 1957 [Oct. 9, 1956], No. 10784/57. Class 99(2). In the manufacture of shells for barrels comprising a sheet of plywood or Masonite (Registered Trade Mark), rolled to cylindrical form and secured in the rolled-up shape by the gluing together of the overlapping edges of the sheet, and external, glued-on, strengthening hoops, the sheet 57 with the hoops 58 attached thereto is secured to and wrapped around a drum 20 rotated through one revolution thereof and tightened against the surface of the drum by a number of chains or other bands 44 which extend almost the whole way around a hoop whereupon the overlapping end portions of the hoops and the intermediate portions of the sheet are subjected to the pressure exerted by a number of separate presser shoes 25 movable towards the drum. As shown, a cylindrical or conical drum 20 divided on an axial plane thereof so that the two parts can be slightly contracted, is carried on a shaft 3 supported in bearings one of which consists of shells 4, 5, the shell 4 being carried by a girder 6 displaceable vertically by a hydraulic or pneumatic jack 10, and the upper shell being mounted on a bar 11 pivoted on a pin 12 and urged in a clockwise direction by a spring 13 ; when the girder is in the raised position, as shown, a projection 14 presses against the bar 11 to keep the shell 5 in contact with the shaft. The latter is connected by an automatically disengageable coupling 15 to a worm wheel 16 which via a worm 17 and chain 18 is driven by an electric motor 19. Above the drum a bridge 21, raised and lowered by screw spindles 22, carries a number of jacks 24 having presser shoes 25 movable radially towards the drum, and jacks 26 equal in number to the hoops to be provided on the barrel. A pair of jacks 27 mounted on the frame of the machine each carry spring-loaded jaws 28 for temporarily holding a clamping rail 29 formed with hooks 30 engageable with latches 31 movably accommodated in the drum. Two jacks 32 carry bearings for a guiding roller 34 parallel with the shaft 3 and mounting sleeves 35 displaceable axially along the roller. For manoeuvring a stop bar 37 is a jack 36 mounted between standards 38 pivoted on pins 39 so as to be movable by screw spindles towards and away from the drum ; the standards support a girder 40 which is movable about the longitudinal axis thereof and to a desired level by screw spindles 41 and carries a number of jacks 42 adjustable in line with the spaces between the sleeves 35 on the roller 34, the spindle of each jack being connected to one end of a chain 44 and the other end of each chain being secured to a pressure bar 45 mounted in a rotatable and axially-adjustable manner in a tube 46 connected by pins 47 to a girder 48 moved towards and away from the drum 20 by a jack 49. To ensure that the drum 20 is locked in an exactly defined position after disengagement of the coupling 15, the shaft 3 carries a projection 50 which at the termination of the rotary motion of the drum abuts a pivoted lever 51 urged against the force of a spring 53 to an operative position by a jack 54 ; a jack 55 presses against a projection 56 on the drum. In operation, the ends of a sheet 57 are chamfered and the leading edge of the sheet is given a curvature corresponding to that of the drum and a number of hoops 58 are attached by glue to the sheet. The leading edge of the sheet is positioned to abut the stop bar 37 and the clamping rail 29 is lowered to engage the latches 31, after which the bar 37 is withdrawn and the coupling 15 is engaged to allow the drum to rotate so that the rail 29 passes under the roller 34 which is then brought into contact with the sheet, the roller pressing against the hoops 58 and the sleeves 35 thereon pressing against the sheet. Before the drum has turned through one complete revolution the lever 51 is brought into engagement with the projection 50, the coupling 15 being automatically disengaged and the drum being locked in position by operation of the jack 55. Operation of the jacks 42, 49 causes the chains 44 to be tightened around the hoops and the jacks 27 are operated to increase the pressure of the rail against the drum. Finally, the jacks 24, 26 load the overlapping edges of the sheet and hoops until the glue has hardened. After withdrawal of the jacks 24, 26, 32, 42, 49 and 27, the jack 10 is operated to bring apart the bearing shells 4, 5 for removal of the barrel shell from the drum and to condition the machine for a further operation. Electric heating means to facilitate hardening of the glue may be provided within the drum or presser shoes. There may be a projection of the drum for actuating successively valves supplying pressure fluid to the jacks and withdrawal of the latter may be controlled automatically by time switches. Two machines may be coupled together and driven by the motor 19.