Patent GB-1065731-A (GB)
Title: Apparatus for producing a uniform tobacco stream or filler
IPC: A24C5/18
Filed: 1964-06-03
Abstract: 1,065,731. Cigarette-making machines. K. KÍRBER. June 3, 1964 [June 5, 1963; June 11, 1963 (2); Jan. 11, 1964], No. 22956/64. Heading A2C. [Also in Division G1] A method for producing a tobacco fleece for use in the production of a tobacco filler comprises supplying tobacco filler material to a weighing device, successively delivering equal-weight portions of tobacco to a surface on which the portions are collected to form a fleece and timing the delivery of such tobacco portions at uniform time intervals to produce a tobacco fleece containing a constant average amount of tobacco per unit length. First tobacco feed device:- The machine for carrying out the method includes a first feed device 101 (Fig. 4a) preceding the weighing device 102 (Fig. 4b) and a second feed device 126 (Fig. 5) following the weighing device. The first feed device 101 comprises an endless band 129 on which tobacco 131 is showered. The band 129 passes around rollers 127 and 128 and feeds the tobacco to a carding roll 135. The roll 135 co-operates with a further carding roll 136 and a spiked beater roll 137 (Fig. 4b) to deliver tobacco to a winnower roll 139 (Fig. 4a) which throws the tobacco forwardly over a second endless band 143. The heavier particles are caught in a trough 150 (Fig. 4b) and carried away by a worm feeder 149 to a trough 147. The remaining particles either fall into a duct 146 or on to the band 143 for delivery into the duct. The duct 146 is formed by walls 144 and 145 the latter wall having hinged thereto a plate 300 which can be moved to close the duct. The belts 129 and 143, and the rollers 135 and 136, are driven from a motor 160. The beater roll 137 and winnower roll 139 are driven from a motor 158. Tobacco weighing device:- The weighing device 102 (Fig. 4b) comprises a weighing container 118 into which tobacco falls from the duct 146. The container 118 includes two shafts Y3, Y4, each with four blades (two of which form the bottom of the container at any given time), which are rotatably supported in members 185, 186. Bearing rings 190-193 are arranged on the ends of the shafts 183 and 184 and co-operate with recesses 196-199 in stationary bearing members 194, 195. Bearing members are provided above the members 194, 195, one only, 200, being shown. These members have recesses which clamp the bearing rings against the recesses in the stationary members 194, 195, when members 200 are moved downwardly. Such movement is effected by energization of an electromagnet 205, the armature 204 of which is connected to a rod 203 on which are provided rods 201, 202. The rods 201, 202 are displaceable in the bearing members 194, 195 and are connected by springs 210 to the members 200. During filling the container 118 is suspended freely from cable 171 and 172. The rod 203 has fixed at one end 251 a further rod 252 the other end of which carries a driver member 253. The member 253 is mounted on a pin 260 on which a catch arm 261 is also mounted. Anti-clockwise rotation of the catch arm is prevented by engagement of the member 253 with a stop 255 on the rod 252. A catch disc 270 is provided on the end of the shaft 183. The disc has four pins which co-operate with the arm 261. The arrangement is such that on reciprocation of the rod 252 the disc 270 is rotated through 90 degrees. The shaft 183 and shaft 184, through gears 188, 189, are rotated through 90 degrees thus emptying the container 118, the blades which formed the bottom of the container being replaced by those which were previously vertical. The container is emptied by energization of the solenoid 205 at regular intervals which are longer than the time needed for it to fill so that the rings 190-193 rest in the recesses in the members 194, 195 when the solenoid 205 is energized to clamp the rings 190-193 with the members 200 and to empty the container. The cables 171, 172 are attached to a weigh beam 312 pivoted on a projection 311 of a carrier 310 suitably fixed to the machine casing. The beam 312 is connected by a spring 315 to a counter weight rod 317 adjustable by means of a screw 322. The cables 171, 172 pass over knife-edged rocker plates 324 and 328. The block 324 carries an opaque strip 325 which interrupts the light beam between a source 326 (Fig. 4a) and a photo-electric cell 327 (Fig. 4b) when the container 118 has filled with tobacco sufficiently to overcome the bias of the weigh beam 312. Interruption of the light beam causes energization of an electro magnet 303, the armature of which is connected to the pivoted plate 300 of the duct 146, to close the duct 146. At the same time the motor 160 is de-energized to stop further feed of tobacco to the duct 146. When the container 118 has been emptied by subsequent operation of the electro magnet 205, the light beam between the parts 326 and 327 will again be uninterrupted so that the plate 300 will be operated to open the duct 146 and the motor 160 will restart. Second tobacco feed device:- The feed device 126 consists of a guide surface 401 arranged beneath the container 118 and continued by the upper run of an endless cloth belt 403 running on rollers 402, 432. A second endless belt 404 is positioned above the belt 403 and is supported on rollers 400, 405, 406 and 407 at a distance from the belt 403 substantially equal to the thickness of the fleece to be formed. A carding roll 408 takes tobacco from the belt 403. A combing roll 409, co-operating with roll .408, delivers the tobacco to a conveyer belt 434 running transversely to the feed direction of the device 126, for conveyance to the rod forming apparatus. The belts 403, 404 and rolls 408 and 409 are driven from the motor 450 which also drives a cam shaft 424. The cam shaft 424 carries a cam 423 which causes reciprocation over the surface 401 of a plunger 412, by means of links 415, 417. The end face of the plunger 412 is arranged obliquely to the feed direction of the belts 403, 404 as also may be the container 118. The second cam 425 operates a lever 427 to raise and lower the roller 407 as the plunger 412 pushes a portion of tobacco 470 between the belts 403, 404. A third cam 471 operates a switch 473 once per revolution of shaft 424 which controls the electro magnet 205 of the weighing device. Instead of raising and lowering the roll 407, the roll 407 may be stationary but preceded by a guide surface arranged on a pivoted arm and forming an extension of the lower run of belt 404. The surface is tangential to the roll 407 and is pivoted in timed relation to the plunger 412 (Fig. 10, not shown). In a further embodiment the belt 404 is replaced by a presser plate. The roll 407 is stationary and is preceded by a further presser plate which is reciprocated at right angles to the belt 403 (Fig. 11, not shown). Operation:- Tobacco is fed by the feed device 101 to the weighing device 102 until the desired portion has been collected in the container 118. The container then descends and the light beam between the parts 326 and 327 is interrupted by the strip 325. This causes operation of electro magnet 303 to close the duct 146 with the plate 300 and de-energization of the motor 160 to stop further feed of tobacco to the weighing device. As cam shaft 424 rotates switch 473 is operated to energize electro magnet 205 to empty the weighing container 118 on to the surface 401. Further rotation of the shaft 424 causes opening of switch 473 to de-energize electro magnet 205. The container 118 then returns to its original position where the light beam between parts 326 and 327 is uninterrupted. Electro magnet 303 is thus de-energized causing plate 300 to open duct 146, and motor 160 restarts. Continued rotation of shaft 424 causes the roller 407 to lift to receive the portion of tobacco which is pushed forward by the plunger 412.