Patent GB-672990-A (GB)
Title: Improvements in and relating to the dumping of the contents of containers
IPC: A21B3/18
Filed: 1949-09-02
Abstract: 672,990. Roller conveyers for dumping bread out of pans. BAKER PERKINS, Ltd. Sept. 2, 1949. [Sept. 17, 1948] No. 22767/49. Class 78 (i). (Also in Group XL (b)] An apparatus for dumping the contents of containers, comprises means for conveying a series of the containers to a dumping station, said means including means for accelerating successive containers as they are thus moved toward the dumping station so as to thereby space the containers, and means located at the dumping station and adapted to receive successive containers from the conveying means and to dump the contents of said containers. Fig. 1. General. Pans 25, containing loaves 26 and strapped together in fours by straps 27, are conveyed through an oven by endless oven conveyer 22 (driven by polygonal drum 24) and delivered therefrom on to slow inlet rolls 43 whence they pass on to intermediate rolls 44 where they intercept a beam of light passing from lamp 47 to photoelectric cell 4G. The said cell acts as a switch and causes intermediate rolls 44 (which normally rotate at the speed of slow rolls 43) to accelerate to the speed of fast outlet rolls 45, so that the pan-straps are spaced apart yet kept in alignment. Each pan-strap 27 then abuts against gate 50 whilst travelling along fast rolls 45. Gate 50 yields when a force of sufficient weight is pressed against it (thus ensuring that the panstraps are parallel to the rolls) and permits the pan-strap to fall on to dumping structure 51, which swings anticlockwise to position 51<SP>1</SP> to eject the loaves 26 (as shown) whilst retaining the pan-straps including tins and then swings clockwise to position 51<SP>11</SP> to deliver the pan-straps to endless conveyer 32. The loaves 26 are orientated by intercepting means 54 and fall into receiver 52 whence they are delivered on to conveyer 33 (or 34, see later). Inlet rolls 43 (Fig. 7). Inlet rolls 48 are journalled between two arms 60 pivoted at the bottom thereof to fixed frame 61. The arms lean to the left and by means of follower 63 bearing on polygonal cam 64 formed on polygonal drum 24, follow the movement of the said drum so that inlet rolls 43 move backwards and forwards towards the drum 24 to receive the pan-straps therefrom. The driven sprocket 65 for the said inlet rolls 43 is driven by chain 87, spring- biassed sprocket 89 allowing for the said oscillatory movement. Speed -synchronised drive to jackshaft 81 (Fig. 6). Motor 68 drives variable-speed pulley 69 which drives jackshaft 81 (which supplies motive power to all the rolls) through V-belt 70, pulley 71, pulley 76, belt 78, pulley 77, gear box 79, shaft 80, chain 82, and sprocket 84 fixed on the said jackshaft. The speed of jackshaft 81 (i.e. of the said rolls) is synchronised with that of polygonal drum 24 (i.e. of the oven conveyer) by means of said variable-speed pulley 69 and differential gear 113- 114, as follows. The drive from jackshaft 81 is transmitted to pinion 114 through sprocket 127, chain 126, sprocket 128 rigidly connected to said pinion 114 and both rotatably mounted on shaft 115. The drive from the polygonal drum 24 is transmitted to pinion 113 through chain 120, sprocket 121, shaft 122, gear 123, gear 124 rigidly connected to pinion 113. Any difference between the speeds of these two drives is transmitted to vary the distance between pulleys 71 and 69 and therefore to vary the speed of the latter pulley and thus that of the jackshaft, the said transmission passing thereto through planet pinion 116 fixed to rotate shaft 115, sprocket 132, chain 131, sprocket 133, shaft 130, threaded sleeve 134 and bellcrank 72 which is pivoted at 73 and carries the said sprocket 71 on its layer arm. Drive to rolls from jackshaft 81 (Figs. 5 and 6). Slow (inlet) rolls 43 are driven from said jackshaft through sprocket 88, chain 87 and sprocket 65 connected to one of the said slow rolls (which are interengaging). The intermediate rolls 44'are also driven at the same slow speed by the said chain 87 engaging sprocket 90 connected to the said interengaged intermediate rolls by an over-running clutch 99 but are also driven at said fast speed when the photo cell is operated, the over-running clutch then disengaging from the low speed. The said high speed drive passes to the intermediate rolls 44 from the jackshaft 81 through sprocket 96, chain 98 and sprocket 97 connected to the said rolls, sprocket 96 being clutched to the jackshaft through clutch 93 operated through bellcrank 103 by solenoid 106 when the latter is energized by the photo cell. The fast (outlet) rolls 45 are driven from the jackshaft through sprocket 109, chain 108, and sprocket 110 on one of the said fast mutually-engaging rolls. Gate 50 (Fig. 7). Gate 50 is swung into or out of stopping position by one revolution of a single-revolution clutch 146 driven from the fast rolls 45 through gear 148. Energization of solenoid 150 lifts pivoted catch 147 to allow the single revolution of the clutch and thus of cam 146 and of arm 156 both fixed thereto. The cam 146 operates gate 50 through follower 144, lever 143, rotary shaft 142, lever 141 and shaft 140 carrying the gate 50. When a pan-strap strikes the gate 50, and adjusts itself to alignment, the weight thereof causes rotation of the 141-143 lever system and therefore of arm 154, which is secured to shaft 140 and which closes switch 153 which energizes solenoid 150 to effect the down-and-up movement of gate 50 to release the pan-strap. The arm 156 closes switch 157 of the electrical circuit. Movement of the dumping structure 51 (Figs. 1, 3, 4). The dumping structure consists of table 160 fixed (by clutch 221, see later) to rotatable shaft 161 and rotates (when a panstrap released by gate 50 has been fed to it from outlet rolls 45) anticlockwise to position 51<SP>1</SP> to eject the loaves whilst retaining the panstrap and then clockwise to position 51<SP>11</SP> to eject the pan-straps to conveyer 32. The rotation is effected from reversible motor 168 through pulley 166, belt 167, pulley 164, gear box 165, gear 163 and gear 162 fixed to said shaft 161 ; the double swing being governed by cam 171 fixed to said shaft 161 and by cruciform 178 pivoted at 179, as follows. Shaft 161 first rotates clockwise (Fig. 4) from its normal position to position 51<SP>1</SP> at which point it reverses due to shoulder 175 striking reversing switch 172 and as it return projection 177 strikes cruciform 178 to cause actuation of switch 174 in the electrical circuit. Next, the shaft reverses at position 51<SP>11</SP> due to the shoulder 176 actuating said reversing switch 172 and thus rotates clockwise to cause projection L77 again to strike cruciform 178 and to thus actuate limit switch 173 to bring the shaft to rest back to its normal position. Sudden ejection of loaves from dumping structure 51 (Figs. 5 and 12). As the dumping structure is rotating to the loaf-ejecting position 51<SP>1</SP> it is released from the motor drive described above and the movement to that position is completed by biassing spring 185 to forcibly accelerate the said structure till it is suddenly stopped in said position by the table 160 striking abutment 232. This release is effected by clutch 221 of which arm 222 is fixed to shaft 161, the dumping structure 51 being rigidly carried by tube 220 freely rotatable on shaft 161 and coupled thereto by a flange 224 thereof which has a notch 225 engaged by the spring-loaded pawl 223 pivoted to and forming part of said arm 222. When the said structure rotates anticlockwise the pawl 223 is caught by stationary element 230 so as to declutch the structure from the shaft 161 and the rotation is continued under the impulsion of spring 185 which, through chain 18C fixed to sprocket 188 fixed to said structure 51, accelerates the said structure till it is stopped in position 51<SP>1</SP> by abutment 232 and then reversed. Said element 230 is pivotally carried by bracket 233 the position of which is adjusted by thumb screw 236 which adjusts the position of supporting bolts 234 in slots 235. Also handle 239 works eccentric 238 to elevate said element 230 in the case when the use of spring 185 is not required. Retaining of pan-straps on the dumping structure (Figs. 9, 10 and 11). The dumping structure 51 receives a full pan-strap from rolls 45, the pan-strap dropping on to the table 160, the bottom part of the pan-strap being held by lip 194 and the upper part thereof being gripped by a series of elements 200. Each gripping element is pivoted at 199 on a bracket 198 fixed on rotatable shaft 197 and the said elements are urged, individually by springs 203 and collectively by spring 211 acting through cable 209 fixed to pulley 208 fixed to said shaft 197, into engagement with the pan-strap to retain the said pan-strap when the dumping- structure 51 rotates to the left to dump the loaves therein and to release the pan-strap when the structure 51 rotates to the right, so that the pan-strap is conveyed away by endless conveyer 32. Receiver 52 (Figs. 3 and 5). The loaves fall from dumping structure 51, are righted by roll 54 and deposited in receiver 52. The latter has a fixed wall 243 and a gate 55 and the loaves are first pushed together by inward moving bars 244 and 245 before being released bv the release of the said gate. The movements of both the bars and gate are derived from driven shaft 264 ; the movement to the bars passing from said shaft through cam 259, follower 260, lever 256 pivoted at 258, rod 250, and arms 246 and 247 pivoted at 248 and 249 and carrying said bars 244 and 245 respectively ; and the movement to the gate passing from said shaft through cam 272, follower 276 carried by pivoted support brace 277, member 275 on which is mounted the follower 276, arm 274, and rotary shaft 273 which rigidly carries said gate 55. The movement of shaft 264 is derived from jackshaft 81 through chain 265, sprocket 266 and said single revolut