Patent GB-716569-A (GB)
Title: Conveyor apparatus for separating articles fed thereto in seriatim
Inventor: JENNEY RAY SAM
IPC: B65B35/28
Filed: 1952-01-30
Abstract: 716,569. Photo-electric control of conveyers. KELLOGG CO. Jan. 30, 1952, No. 2564/52. Class 40 (3). [Also in Groups XVII and XXX] In a machine for changing series movement of articles to substantially parallel transverse movement, e.g. for feeding a packing machine, a series movement conveyer has means for displacing articles downwardly therefrom onto a transverse conveyer disposed below it, and means, e.g. a series of photo-electric devices, for progressively actuating the articledisplacing means in timed relation with the continuous passage of articles on the series conveyer to dispose the articles on the transverse conveyer in spaced lateral relationship with each other. As shown, shredded wheat biscuits conveyed in contacting series relationship by an endless conveyer belt 2 are first discharged down a shoot below a rotating wheel 29 having a spongy rubber periphery, the peripheral speed of wheel 29 being greater than the linear speed of the biscuits whereby the latter are accelerated and separated before passing on to a second conveyer belt 13. Belt 13 travels past a series of electric eye assemblies 89 each comprising a light source 100, Fig. 4, and a photocell 97 such that the biscuits 3 on the belt break each of the beams of light from the light sources to the photocells as they travel with the belt. Each photocell 97 is connected to a thermionic valve control assembly 107<SP>1</SP> which functions to control a set of solenoid-operated valves 105 corresponding to the series of electric eye assemblies 89, each corresponding valve 105 being adapted to control feed of compressed air to an air jet 103 located in the same transverse plane of the belt 13 as the corresponding electric eye assembly. The control assembly is such that the biscuits are progressively ejected from the belt 13 into a plurality of passageways 75 in a covered shoot 73 by means of sequential operation of the air jets by the photocells in the following manner, viz :-initially, all the photocells 97 are incapable of opening their respective valves 105 except the one most remote from the entrance end of belt 13, which is thus actuated upon breaking of the light beam from its light source 100 by the leading biscuit on the belt. This operates the corresponding valve 105 thus causing a blast of air from the corresponding jet 103 to blow the leading biscuit into the passageway 75 most remote from the entrance end of belt 13. Actuation of this photocell 97 also causes the control assembly 107<SP>1</SP> to condition the next photocell 97 such that the next following biscuit upon breaking the corresponding light beam is blown by the next jet 103 into the next passageway 75 nearer the entrance end of belt 13. The operation proceeds in this way until all the passageways have received a biscuit whereupon an extra electric eye assembly 101 has its photocell 97 conditioned whereby the next biscuit actuates this photocell to reset the control assembly 107<SP>1</SP> into its initial state. This biscuit then continues along belt 13 until it reaches the most remote eye assembly 89 whereby the cycle is repeated. As is shown in Fig. 9 the above described operation is accomplished by a control assembly consisting of a series of "hard" valves V1-1 to V1-16 of which the valves V1-2 to V1-16 have their grid bias controled jointly by the corresponding photocells 97-2 to 97-16 and by a series of thyratrons T-2 to T-16, whi e valve V1-1 is control'ed solely by photocell 97-1 which is the photocell most remote from the entrance end of belt 13. Initially the thyratrons are not ionized so that there is no voltage drop across cathode resistors R5 and the grids o' valves V1-2 to V1-16 are too negative for actuation by the photocells 97-2 to 97-16. Only the grid of valve V1-1 is responsive to breaking of the light beam associated with photocell 97-1. Such actuation of photocell 97-1 causes an increased voltage across resistance R1-1 which causes a corresponding increase in anode current of valve V1-1 which in turn actuates a relay 108-1 for the corresponding solenoidoperated valve 105. The resultant increase of vo tage across relay 108-1 through inter-valve coupling C1-1, R3, R4 causes thyratron T-2 to "strike" causing a current to flow through resistors R2 and R5 in the anode-cathode circuit thereof, the resu'tant voltage drop across resistor R5 reducing the bias on valve V1-2 to the correct value or actuation, in a similar manner, of relay 108-2 by photocell 97-2. The operation continues from stage to stage until final'y valve V1-16 is actuated by the photocell 97-16 of electric eye assemb y 101 to cause operation of relays RY2 and RY1. Relay RY2 opens a switch S.W. cutting off the H.T. supply to all the now-running thyratrons and relay RY1, which is a delay relay, opens switch S.W.1 cutting off the H.T. supply to valve Vl-16 a ter a delay to allow de-ionization o the thyratrons, thus restoring the circuit to its original condition. The biscuits shot into the passageways 75 by the air jets are steadied by leaf springs 75a on the shoot cover of shoot 73 and then pass onto a conveyer belt 47 where they are oriented by a system of diagonal guides 76 and 113 so that they are all moving in the direction of their longitudinal axes. The guides 76 have leaf springs 118 secured at 119 to their ends whih are bent at 121. The leaf springs are split longitudinally from their ends secured to the guides 76 the lower portion 122 of each being bent away from the corresponding guide to form a second leaf spring. A catch 120 holds each leaf spring assembly in a position such that a passageway remains between the end portions of adjacent guides 76 sufficiently wide to allow free passage of biscuits correctly oriented but not biscuits which are incorrectly oriented. The guides 76 tend to orient the biscuits with either their long or their short faces parallel with the rai's but the biscuits may be delivered to the leaf springs in the attitude 125 also owing to friction slowing up the short edge of a biscuit whose short edge had come into contact with a rail. Biscuits with their long faces parallel with rai's 76 pass free'y through the guide assembly into correct orientation. Biscuits with their short faces parallel with rails 76 contact the leading edge of leaf spring 118 and are thus turned into correct orientation by this edge whereafter they pass freely through the rest of the guide assembly. Biscuits in the attitude 125 however engage the leading edge of the leaf spring 118 with their short face 127 in such a way that the spring is depressed whereby the biscuit is allowed to turn clockwise into the position where its short edges are parallel with the rails 76. These biscuits pass onto the bent end portion of rail 76 where they depress the second leaf spring 122. This causes the corner 130 of the biscuit as it passes from the guides 76 to engage the leading edge of one o the guides 113 which turns it into correct orientation as it passes into these guides, which are wider spaced than the width of the biscuit at their leading ends for this purpose. The spacing between guides 113 is progressively reduced until five sets of three passageways are formed of correct width and arrangement for feeding the biscuits to a packing machine for packing five tiers of biscuits, three to a tier, within a carton. If jamming occurs in any of the five sets of feeders in the packing machine the biscuits pile up in the respective three passageways. A switch 132 placed in every third passageway has a trip lever operated momentarily by each passing biscuit. A delay relay is in circuit with each switch however to prevent completion of a circuit un'ess the piling up of biscuits in the respective three passageways causes a biscuit to remain in contact with the trip lever, in which case a circuit is completed which is arranged to de-energize all the photocells 97 so that biscuits on belt 13 remain on it and are received in a hopper at its remote end. If jamming occurs between the switches 132 and the electric eye assembly 101 causing biscuits to pile up on the be't 13 the biscuits are diverted from the entry portion of be't 13 by a deflector 139 which is swung over the belt by a solenoid 137 actuated from a delay re'ay in series with an additional electric eye assembly 134 when a biscuit remains beyond a certain length of time in the light beam of the assembly 134.