US3001648A

US3001648A - Device for segregating selected cigarettes

Info

Publication number: US3001648A
Application number: US567369A
Authority: US
Inventors: Molins Desmond Walter; Wellington Gordon Francis
Original assignee: Molins Machine Co Ltd
Current assignee: Molins Machine Co Ltd
Priority date: 1955-02-25
Filing date: 1956-02-23
Publication date: 1961-09-26
Anticipated expiration: 1978-09-26

Description

Sept. 26, 1961 D. w. MOLINS ET AL DEVICE FOR SEGREGATING SELECTED CIGARETTES Filed Feb. 23, 1956 5 Sheets-Sheet 1 INVENTORS :Desmeu u). Moh'di Gannon! 7*- bU-?ou) t [1 UJuTio-vv, M,

ham wqsw ATTORNEYS Sept. 26, 1961 D. w. MOLINS ET AL 3,001,648

DEVICE FOR SEGREGATING SELECTED CIGARETTES Filed Feb. 23, 1956 5 Sheets-Sheet 3 INVENTOR Dssnonn \J. MOI-INS Gannon: Fw. Powsu.

ATTORNEYS Sept. 26, 1961 D. w. MOLINS ET AL DEVICE FOR SEGREGATING SELECTED CIGARETTES 5 Sheets-Sheet 4 Filed Feb. 23, 1956 Qwmnxh Ins:

INVENTOR .Dzsnmun \J Nouns 6 mm: Eu POWELL ATTORNE Y5 Patented Sept. 26, 1961 3,001,648 DEVIUE FOR SEGREGATING SELECTED CIGARETTES Desmond Walter Mullins and Gordon Francis Wellington Powell, Depfit'ord, London, England, assignors to Molius Machine Company Limited, London, England, a British company Filed Feb. 23, 1956, Ser. No. 567,369 Claims priority, application Great Britain Feb. 25, E55 3 Claims. (Cl. 209-81) This invention concerns a device for segregating selected cigarettes (such as cigarettes of incorrect weight) from a quantity of cigarettes, for example, from the output of a cigarette making machine.

It is known in the operation of continuous rod cigarette making machines to use what are variously termed electrostatic, or high-frequency, detectors for the purpose of measuring the electrical characteristics of the cigarette rod or a stream of tobacco which eventually forms the rod, and rod measurements effected in this way have been used for the purpose of rejecting cigarettes made from defective portions of the rod. The aforesaid detector has a pair of plates made of electrically conductive material through which the rod passes so that the three components form together a condenser. A somewhat similar arrangement is used in one construction according to the present invention and for convenience of description two plates such as those referred to will be termed a condenser pair.

It will be appreciated that such an electrostatic detector has a very quick response, seeing that it is able to detect the condition of a moving cigarette rod and thereafter cause defective cigarettes cut from the rod to be segregated for, as will be understood by those skilled in the art, the space and time available for detection and segregation are both very small. An electrostatic detector is chiefly responsive to the moisture in the tobacco but it is assumed for the purposes of the present invention that this is constant (and under proper conditions it can be kept reasonably constant) and thus the response can be regarded as showing the mass of the rod. It is however possible, with certain reservations, to secure a similarly rapid response from another known detector, namely, one using a source of penetrative radiation such as a beta-ray emitter. In either case the detector response depends on the mass of the cigarette or sometimes, as will appear hereafter, on the mass of part of a cigarette.

According to the invention there is provided a device for segregating selected cigarettes from a quantity of cigarettes comprising a cigarette conveyor, a detector responsive to the mass of a part at least of a cigarette carried on said conveyor, means for feeding the said cigarettes to the conveyor and means controlled by the detector for segregating selected cigarettes from the quantity fed to said conveyor.

Further according to the invention there is provided a device for segregating selected cigarettes from a quantity of cigarettes, comprising a cigarette conveyor, means for feeding cigarettes to the conveyor so that each successive cigarette passes between a source of penetrative radiation and a ray-responsive device to detect variations in the mass of said cigarette from a given standard, and means controlled by said ray-responsive device for segregating selected cigarettes from the quantity fed to said conveyor.

The invention is primarily intended for use with a cigarette making machine and in this case the drum may be arranged near the position where normally cigarettes are deflected, by a device known as a deflector, out of the rod line on to the catcher band. In this case the deflector suitably modified is arranged to move a cigarette lateral- 1y from the rod line into a groove of the drum or into any intermediate device which will complete the movement of the cigarette to the groove.

The invention will be more fully described with reference to the use of the device in a continuous rod cigarette making machine and with reference to the accompanying drawings in which:

FIGURE 1 shows diagrammatically the mechanical parts of a device for use with an electrostatic measuring device;

FIGURE 2 is a fragmentary view of part of FIGURE 1 looking in the direction of the arrow A;

FIGURE 3 is a view of part of FIGURE 1 looking in the direction of the arrow B and partly in section on the line IIIIII;

FIGURE 4 is a sectional elevation of a cigarette drum and its mounting for use with an electrostatic measuring device and drawn to scale;

FIGURE 5 is a front elevation of FIGURE 4;

FIGURE 6 is a diagrammatic representation of the electrical apparatus for use with apparatus constructed as in FIGURES l to 3;

FIGURE 7 shows diagrammatically the mechanical parts of a device for use with a measuring device using a source of penetrative radiation and the electrical apparatus thereof;

FIGURES 8 and 9 are diagrams of modified detector devices.

Referring first to FIGURES 1 to 3 the cigarettes C as they are cut from the rod are carried along a tape 1 and move in front of a reciprocating pusher 2 which deflects them laterally with such speed that they can roll over a plate 3 and fall into one of the grooves 4 of a rotatable drum 5 whose axis 6 is parallel to the rod line. The pusher 2 is operated by a cam 7 and spring 8. If desired the plate 3 may slope downwards to assist in the transfer of a cigarette into the groove or, according to the position' of the drum, an intermediate device of any suitable kind may be provided to feed the cigarette into a groove. The drum 5 continuously rotates in timed relationship with the cigarette machine, moving at a rate equal to one groove per cigarette or, as will most usually be the case, two drums are provided each moving at a rate equal to one groove per two cigarettes produced. The drums will in such case both rotate on the axis 6 and the arrangements for the second drum will be identical with those of the one shown except that the pusher 2 of the second drum will be timed to engage the succeeding cigarette to the one shown on the tape 1. The grooves of the drum are spaced fairly widely apart, for example, there may be as shown, eight grooves on the drum. Each groove 4 is formed in a block 9 of metal and forms one plate of a condenser, the block being held in a pair of insulating supports 10 fixed to the drum periphery. Further details of the construction and mounting of the blocks 9 and supports 10 are shown and described later with reference to FIGURES 4 and 5. The cigarette lies in the groove of the block 9 and as the drum moves onwards from the cigarette receiving position, the cigarette is carried upwards to the top position of the drum and beneath another plate 11 which is fixed. Thus for an instant there is formed a condenser consisting of one moving and one fixed plate with a dielectric between chiefly consisting of the cigarette to be tested.

As hereafter explained with reference to FIGURE 6 the condenser formed by a block 9 and the fixed plate 11 is connected to an oscillator coupled to an amplifier and other electrical apparatus, and causes a signal of a certain amplitude, which is compared in said apparatus with a signal whose amplitude is of a predetermined value equivalent to that produced by the condenser for a cigarette of correct weight. Thus if an incorrect cigarette forms the condenser dielectric at any time the said apparatus will have an output which if suflicient, that is, if the cigarette is too light ortoo heavy by a reasonable amount,'will .close the contacts of .a relay. Closure of the relay .c'cntacts'will close a circuit to a solenoid '12 whose plunger 13 moves to the right in FIGURE 3 as the plunger 13 is magnetized by the solenoid current it inductively magnetizes and attracts and moves a soft iron piston 14, FIGURE 1, which constitutes a valve piece as will now be explained.

The piston 14 is one of eight slidable in valve bodies 15 formed in the body of a rotary suction device 16 having a cylindrical body or hub from which radial suction nozzles 18, equally spaced and equal in number to the flutes in the drum 5, project. The inner end of each valve body is open. As the aforesaid piston 14 moves past the solenoid plunger the latter will pull it out as far as a stop screw 17 will permit. As can be seen from FIGURE 3 if a piston 14 is moved in this manner the interior of the body of the device 16 will be in communication with a suction nozzle 18 through a port 19. The interior of the body of the device 16 is connected by a pipe 20 to a fan or pump 21' whose rotation tends to exhaust the interior of the wheel. Thus as the suction nozzle marked 18A in FIGURE 1 moves round with the device 16 it will, if its piston 14 has been moved as above described, pull the cigarette out of the groove in the block marked 9 and carry it around as it adheres to the nozzle by suction. A cigarette seized in this manner'is shown adhering to the suction nozzle preceding the one marked 18A in FIG- URE 1. V

The rotary suction device is supported in bearings 22 and driven at the same speed as the fluted drum 5 and in timed relationship therewith so that each suction nozzle moves round for a time near a flute in the drum 5 and is thereby enabled to seize a cigarette if the solenoid has operated, that is, the seized cigarette has been detected as being of incorrect weight.

A cigarette seized in this manner is segregated from correct cigarettes by being released from the suction nozzle, as explained below, as the latter approaches a tape conveyor ZB moving at right angles to the plane of the paper which conveyor delivers the cigarette to a receptacle, not shown.

Cigarettes whose weight is correct are not seized in this manner and fall from the flutes 4 over a guide 24 on to a conveyor 25, the usual catcher band of a cigarette machine.

In order that a cigarette seized by a suction nozzle shall be released therefrom the aforesaid piston 14 is moved back to valve closing position as the nozzle is approaching the co'nveyor23. The movement is effected by a cam lever 26 loosely connected to the rod of a hammer 35 whose end is caused to strike the piston smartly and return it almost instantaneously. The rod of the hammer slides in a lug 36 of one bearing 22. The cam lever is pivoted at 27 and operated by a cam 28 engaging a roller 29 on the lever and by a spring 30. The cam 28 is driven at the rate of one revolution per flute of drum 5 by a spindle 31 driven by mitre gear wheels 32 from the shaft 33 of cam 7, as cam 7 rotates at the required rate. r The solenoid plunger 13 is moved back, as the coil is ale-energised, by a spring 34, FIGURE 3.

Electrical apparatus for use with the devices described with reference to FIGURES 1 to 3 is shown'in the block diagram of FIGURE 6 and connecting leads from FIG- URES 1 and 3'are also indicated in FIGURE 6. All the items indicated in FIGURE 6 by blocks are of well known kinds. A copper block 37 in FIGURE 1 is capacitively coupled to each block 0 in turn as the fluted drum rotates and a lead 38 from the block and a'lead 39 from the 4. FIGURE 6 which close at times as controlled by the apparatus shown in FIGURE 6 as will now be explained:

Referring now to FIGURE 6 the output of a standard sinewave oscillator generating, say, 130 megacycles per second and providing a carrier wave is passed to a modulator 101 operating at from 10 to 15 kilocycles per second and the composite signal (chosen as 130 megacycles per second and '10 kilocycles' per second) is applied to the cigarette C'through the

condenser plates

9 and 11, the plate 9 being coupled to the fixed block 37 by capacity as above mentioned. Amplitude modulation is used and the device 101 is a well-known type of amplitude modulator. The cigarette C constitutes a variable coupling in the detector device 9-11 and with all the cigarettes at constant moisture content, the voltage developed in a detector unit 102 depends on the weight of the cigarette which is at that moment between the condenser plates. The detector unit includes an amplitude modulation detector, that is, apparatus comprising any normal means of filtering out'thecarrier wave arranged to remove the 130 megacycles per second component from the composite signal and the 10 kilocycles per second component passes out of the detector unit with a certain amplitude. This is compared in a difference unit 103 for example, a differential transformer, with a standard 10 kilocycles-per second signal fed direct from the modulator 101 along line: 104. Since any phase shiftat the detector position occurs at 130 megacycles per second, this shift will be insignificant on the separated signal of 10 kilocycles per second and therefore no phase compensation is necessary. The difierence unit detects differences in amplitude between the reference signal and the signal due to mass of the cigarette at the testing position. The latter signal will vary according to variations in cigarette mass giving rise to amplitude variation at the test position of the composite wave and the 10 kilocycles per sec ond wave left after the composite signal has been fed into the detector unit 102 has amplitude variations proportional to those in the composite wave. If the cigarette is correct, the amplitude of the signal coming from the detector unit 102 will be the same as that of the standard signal along line 104. In such a case the difierence unit will give zero output. If however the cigarette weight is not correct there will be a definite output from the detector unit. As incorrect cigarettes are to be segregated it is immaterial whether said output is in response to an underweight or overweight cigarette.

The signal is amplified and rectified in a combined amplifier-rectifier unit 105 to secure a DC. output, the amplifier being a current or power amplifier. A switching device 106, that is, a brush engaging a rotating contact disc, is provided to ensure that the output is only available at the time when the cigarette is in the correct position for detection. The disc rotates at the rate of one revolution per test and has a single contact. Any detector signal of 'suflicient magnitude coming from the apparatus is passed toa high speed relay 107. This is an ordinary magnetic relay having contacts operated by movement of the magnet armature; The contacts of this relay are diagrammatically shown at 108. If the contacts 108 of this relay close, the solenoid 12, FIGURE 3, is energised by the battery 109 and. rejection of an incorrect cigarette takes place as previously explained with reference to FIGURES 1 to 3.

As previously mentioned FIGURE 1 is a diagrammatic showing and correct mechanical details of the fluted drum are shown to scale in FIGURES 4 and 5. The drum 5 is fixed to the rotatable shaft 6 which is supported in a square conductive bush 110 fixed in a support plate 111. On the bush is fixed a bracket 112 at the top of which is fixed an insulating block 113 in which the bar 37 is mounted.

Connection to the bar 37 is by the cable 38. The grooved block 9 is supported in the insulating supports 10 which are fixed in grooves formed in the rim of the drum 5, and the bar 87 and block 59 are capacitively coupled as the fluted drum rotates in the manner described with reference to FIGURE 1. p

The upper condenser plate 11 is supported by an insulating bracket 114 and connection is made to the plate 11 by the cable 39.

It will be understood that as the electrical apparatus for use with the constructions so far described involves very high frequencies that the various electrical elements shown in FIGURES 1, 4 and are properly constructed, arranged and connected in accordance with the practice in these high frequencies.

Apparatus for detecting cigarettes by means of a source of penetrative radiation such as a beta-ray device is shown in FIGURE 7. In this case the cigarettes C are fed to a rotatable drum 120 having a flange 121 at the far end in the figure, the near end being open. It is necessary for successful detection that the cigarettes should be in a definitely fixed position relatively to the beta-ray device and to secure this the cigarettes are held in slots 122 in the drum periphery and are lightly pressed into said slots. Cigarettes are fed radially to the drum by a pusher 123 as in the previous case but the pusher has a resilient end' 124 and exerts a slight yielding pressure on a cigarette as it enters a drum slot. An arcuate guide 125 made of springy material retains the cigarettes in the slots and presses lightly on them to ensure that they are correctly positioned as they approach the scanning position. A beta-ray source 126 is fixed in the position shown and above the cigarette being scanned is an ionisation chamber 127. This is filled with a mixture of argon and carbon di-oxide. The guard ring 127A of the chamber is grounded as shown and a high voltage negative potential is applied to the outer member of the chamber 127. Current due to ionisation flows in a resistor 128 and causes a voltage to be applied to the input terminal 129 of an amplifier 130. An amplified version of this voltage appears at the output terminal 131. A large fraction of the output voltage is taken off a potential divider 132 and applied as degenerative feedback to the lower end of 128 so that with the gas filled ionisation chamber and a short input circuit time constant consequent on the large feedback, the rapid response enables the pulse height at the output 131 to be proportional to the weight of the individual cigarettes passing through the scanning position as the drum revolves.

A potential divider 133 allows a reference voltage to be selected and a rectifier 134 and high speed relay 135 are arranged so that when a pulse height at 131 exceeds that of the reference voltage at 133 the relay operates. Suitable power supplies are provided in the usual manner and are normally housed with the amplifier 130.

Operation of the relay 135 causes a solenoid 136 to be operated and a selected cigarette is segregated in the following manner.

As a cigarette moves away from the scanning position the ionisation current will speedily die down so the solenoid 136 has to be energised at the time an unsatisfactory cigarette is detected at the scanning position. Such cigarette must be ejected before the drum 120 has moved a complete slot pitch so ejection is effected by a reciprocating bar 137 at the position shown. The solenoid is therefore provided with a hold on contact device so as to be energised at the time when the slot carrying the defective cigarette is at the ejecting position.

The bar 137 is guided in a guide 138 fixed to a stationary shaft 139 on which the drum 120 revolves and is reciprocated by a cam rod 142 operated by a spring 149 and a cam 141. The cam is driven at the rate of one revolution per drum slot, and the working stroke of the bar is caused by the spring 140. The solenoid has a plunger 146 the end of which can move past a stop 143 on the cam rod. As long as satisfactory cigarettes appear at the scanning position the plunger end is as shown and the cam follower 144 on the rod 142 cannot follow the contour of the cam so the bar 137 is stationary. When an incorrect cigarette appears at the scanner the contacts of relay close and current is fed from a battery 145 to the coil of 136. The plunger is retracted and in due course the depression shown in the cam reaches the cam follower and the bar 137 makes a very quick ejecting stroke. The solenoid 136 is first energised as above remarked through the contacts of relay 135 and battery 145 and as soon as the coil is energised, it pulls down a spring contact arm 147 and connects it to another contact 148 leading to the battery, so the coil 136 remains energised although the cigarette that has been scanned is moving away from the scanning position. As soon as the ejector has made its stroke the follower 144 moves on to the outer part of the cam periphery and the stop 143 is then again as shown on the drawing and the end of the plunger 146 can move back again to the position shown as soon as current is cut oil from the coil 136. This is effected by a pin 149 at the back of the cam 141 which opens normally closed contacts at 159. The solenoid plunger moves out again under pressure of a spring 151 and remains in that position preventing operation of the cam rod 142 until another defective cigarette is detected.

Cigarettes ejected by the rod 137 are attracted by a suction drum 152 and deposited on to a conveyor 153. Satisfactory cigarettes move on past the ejector position and are blown out of the slots by a blower 154 and fall on to a conveyor 155.

This beta-ray apparatus is responsive only to cigarettes lighter than the desired weight, the drum material between successive cigarettes being heavy relatively to a cigarette, that is, it otters a resistance to the passage of the rays considerably greater than that of a heavy cigarette. Thus the lighter a scanned cigarette is the higher will be the corresponding pulse of ionisation current. Machines to which the equipment is to be fitted would in the normal way have some sort of device for keeping the weights relatively constant and it is very important from the sales point of view that light cigarettes should be segregated so the loss due to the passage of heavy cigarettes is not over important.

Hitherto the description has referred to the segregation of selected cigarettes and further explanation of the word selected is required. In some cases segregated cigarettes are those whose mass is above or below requirements. But it will be appreciated that a cigarette might have the necessary mass but have, for instance, one part overweight and the other part underweight. In order to meet this contingency the condenser plates of the electrostatic apparatus may be arranged as two pairs of plates separated at their mid-length as shown in FIGURE 8. In this figure the drum is marked 160, the top condenser plates 161 and the lower plates 162. The distance between each pair of plates may be greater or less depending on whether it is desirable to detect only the extreme ends or a greater proportion of a half length and depending also on the apparatus employed for one condenser must not interfere with the other. In this case the detector devices detect each half and cause those cigarettes having an imperfect half-length to be segregated.

In a similar manner half-lengths can be detected by a beta-ray device as shown in FIGURE 9 where the two scanners are separated by screens 163 and 164.

What we claim as our invention and desire to secure by Letters Patent is:

1. A device for segregating cigarettes of incorrect weight from a quantity of cigarettes, composed of correct and incorrect wei ht cigarettes, comprising a cigarette conveyor including a rotatable drum having a number of flutes parallel to its axis spaced around its periphery whereby cigarettes located one in each flute are conveyed laterally with respect to their length in positively spaced relationship, each flute of the drum comprising a metal flute plate against which a cigarette can lie, and a fixed metal plate mounted in a position such that each successive flute plate passes the fixed plate and forms therewith at the said position a pair of condenser plates constituting a detector, and means for feeding a cigarette to each of the flutes of the drum so that the cigarette constitutes at least the major part of the condenser dielectric when passing the fixed plate, a first conductor connected to a flute plate at the detecting position and a second conductor connected to the fixed plate, a high-frequency generator connected to said first conductor and a detecting system connected to said second conductor, whereby the capacity of said condenser having at least part of a cigarette between the plates causes a signal whose amplitude is compared in the detecting system with a signal having an amplitude equivalent to that which would have been produced by a correct cigarette positioned between the plates and means forsegregating cigarettes of incorrect weight, said means operating in response to an output from the detecting system resulting from a predetermined difference between the compared signals.

2, A device for segregating cigarettes of incorrect weight from a quantity of cigarettes, composed of correct and incorrect weight cigarettes, comprising a cigarette conveyor including a rotatable drum having a number of flutes parallel to its axis spaced around its periphery, whereby cigarettes located one in each flute are conveyed laterally with respect to their length in positively spaced relationship, each flute of the drum comprising a metal flute plate against which a cigarettecan lie, and a fixed metal plate mounted in a detecting position such that each successive flute plate passes the fixed plate and forms therewith at the said position a pair of condenser plates, and means for feeding a cigarette to eachv of the flutes of the drum so that the cigarette defines at least the major part of the condenser dielectric when passing the fixed plate, a first conductor connected to a flute plate at the detecting position and a second conductor connected to theifixed plate, a high-frequency generator connected to said first conductor and a detecting system connected to said second conductor, whereby the capacity of the condenser having the mass of at least part of a cigarette between the plates causes a signal whose amplitude is comparedin the detecting system with a signal having an amplitude equivalent to that which would 7 have been produced by a correct cigarette positioned between the plates, means for segregating cigarettes of incorrect weight from the quantity fed to said conveyor, said means operating in response to an output from the detecting system resulting from. a predetermined 'difierence between the compared signals and comprising a rotary suction device having suction nozzles each of which is adapted to be rendered active by said detecting system and remove a cigarette of incorrect weightfrom its flute, and means for rendering a nozzle active as it approaches a flute containing a cigarette selected for segregation.

3. Adevice for-segregating cigarettes of incorrect weight from a quantity of ,cigarettes composed of correct and incorrect weight cigarettes, comprising a cigarette conveyor which conveys cigarettes laterally with respect to their length and in positively spaced relationship, a plurality of plates of electrically conductive ma terial spaced apart and movable therewith, a fixed plate ofsaid material mounted in a position such that each successive moving plate passes the fixed plate and forms a condenser therewith, and means for feeding cigarettes to the conveyor, wherein each successive cigarette lies near each successive moving plate and in a position to constitute at least the major part ofthe condenser dielectric when passing the fixed plate, a first conductor connected to a moving plate at the detecting position and a second conductor connected to the fixed plate, a high-frequency generator connected to said conductor, and a detecting system connected to said second conductor, whereby the capacity of the condenser having at least part of a cigarette between the plates causes a signal whose amplitude is compared in the detecting system with a signal having an amplitude equivalent to that which would have been produced by a correct cigarette positioned between the plates and means for segregating cigarettes of incorrect.

weight from the quantity fed to said conveyor, 'said means operating in response to an output from the detecting system resulting from a predetermined difierence between thecompared signals.

' References Cited in the file of this patent UNITED STATES PATENTS 1,846,808 Holm et al. Feb. 23, 1932 2,237,254 Broekhuysen Apr. 1, 1941 2,357,860 Whitaker Sept. 12, 1944 2,694,310 Pounds Nov. 16, 1954 2,704,079 Molins et al. Mar. 15, 1955 2,729,214 Broekhuysen et a1; Jan. 3, 1956 .2,732,503 Jacobs Jan. 24, 1956 2 ,737,186 Molins et a1. Mar. 6, 1956 2,742,150 Rendel Apr. 17, 1956 2,757,675 Powell Aug. 7, 1956 2,759,108 Molins Aug. 14, 1956 2,861,683 Gilman Nov. 25, 1958 FOREIGN PATENTS 528,014 Great'Britain Oct. 21, 1940 699,129 Great Britain Oct. 23, 1953 741,932 Great Britain Dec. 14, 1955 942.164, France Sept. 13, 1948