Patent GB-527947-A (GB)
Title: Improvements in or relating to methods and machines for forming filter units of star-shaped configuration
IPC: B31D5/00
Filed: 1939-04-24
Abstract: 527,947. Making filters. MOTOR IMPROVEMENTS, Inc. April 24, 1939, No. 12272. Convention date, June 17, 1938. [Classes 83 (ii) and 83 (iv)] Corrugating. A machine for forming a filter unit of star-shaped configuration comprises a plurality of slides 26 adapted to move towards and away from the central axis of a tubular filter blank and to co-operate with a mandrel 18 movable into and out of the blank. The mandrel 18 comprises a body portion 19 and radial slides 20, normally held in their inner positions by a ring 24 urged downwardly by springs 24a, and is mounted on a head 14 supported by a piston rod 16 above the bed 10 carrying the radial slides 26 which are retained in their outer positions by springs and are connected by cables 1 and 2 to a head 31 on a piston rod 32. The filter F, comprising a cylindrical wire screen overlaid with filter paper, is supported by the bed 10 and surrounds an assembly comprising a tube T on which is threaded a bush B<SP>1</SP> and an end cap C<SP>1</SP> containing a gasket. The cap rests on a ring 100 arranged in a recess in the bed and supported above the bottom thereof, when the head 31 is in its upper position, by rods 103 on the head engaging a ring 102 connected to the ring 100 by rods 101. When switch 37a is closed, coil 35a is energized to move valve 34 to cause the mandrel to descend, and when rods 25 on ring 24 contact with the cap C', the ring is lifted and the slides 20 move to form the filter cylinder into a polygon. After the mandrel has come to rest on the bed the piston continues to move, due to the last motion connection with the head 14, and the members 38, 39 move the rod 41 against the action of a spring to actuate the valve 43 to cause the piston rod 32 to descend and move the slides 26 inwardly and set the filter screen to the form. in Fig. 8, the slides 20 being returned to and locked in their inner positions. As the head 31 nears its lower position it closes and then opens switch 37b thereby energizing coil 35b to actuate the valve 34 to return the mandrel to its upper position. As it moves upwardly valve 43 is actuated by a spring and the piston 32 ascends to allow the slides 26 to move outwardly. Valve 43 is then actuated by hand lever 45 and the slides 26 move to set the filter to the form in Fig. 10. Spinning. The upper end cap C and its bush B, Fig. 11, are placed in a recess in a plate 60 pivoted on a post 61 on the bed 10 and notched to engage a post 62 when moved into a position above the formed filter. A lever 64 journalled on standard 12 is connected to a plate 60 by a link 65 and is fitted with a vertical sleeve 64a surrounding a rod 64b urged upwardly by a spring. A spring 60<SP>1</SP> normally holds the plate in an inclined position. The post 62 is supported by a spring 66 and the lower end of the post is connected by a spring 67 to the head 31 so that handactuation of lever 45 results in downward movement of the post 62 to clamp the plate 60. Cap C is then slid along and drops through the aperture in the plate to rest on the filter. Switch 37a is then closed and the mandrel moves down into contact with plug 75 in bridge piece 73 on plate 60 and the plug moves to engage the rib b on bush B and the plunger 79 enters the bush. The member 39 has meanwhile depressed rod 64b to contact with rod 41 to prevent movement of valve 43. Treadle 88 is now actuated to start the motor 72 to rotate the spinning tool 59 and to operate valve 85 controlling fluid supply to cylinder 82 to cause movement' of lever 49 to raise the tool to spin over the lower end of the bush B Switch 37c is then closed to effect raising of the mandrel with consequent raising of the head 31 and release of the plate 60.