US2357860A

US2357860A - Cigarette detecting and correcting

Info

Publication number: US2357860A
Authority: US
Publication date: 1944-09-12
Anticipated expiration: 1961-09-12

Description

Sept. l2, 1944. u. A. wHlTAKl-:R

CIGARETTE DETECTING AND CORRECTING APPARATUS Filed April 2, 1941 8 SheeLS-Sheet l INVEToR UNcAs A.wH|TAKER BWM TTORNEY Sept. l2, 1944. u. A. WHITAKER CIGARETTE DETECTING AND CORRECTING APPARATUS 8 Sheets-Sheet 2 Filed April 2, 1941 FIC-3. 3

a; 27o/6%* M 64 4&9 INVENTOR UNCAS A.wH|TAKER TTORNEY SePt- 12, 1944- Y u. A. WHITAKER 2,357,860

CIGARETTE DETECTING AND CORRECTING APPARATUS INVENTOR UNCAS A.WH|TAKER WWW ATTORNEY Sept. 12, 1944. u. A. WHITAKER CIGARETTE DETECTING AND CORRECTING APPARATUS Filed April 2, 1941 8 Sheets-Sheet 4 INVENTOR UNcAs A.wH|TA R ATTORNEY Sept. l2, 1944. u. A. WHITAKER CIGARETTE DETECTING AND CORRECTING APPARATUS Filed April 2, 1941 B Sheets-Sheet 5 INVENTOR UNCAS A.WHITAKER A. MMM.

CIGARETTE DETESTING AND CORRECTING APPARATUS Filed April 2, 1941 B Sheets-Sheet 6 Nw @w @v www ww www H W u www. .....Hw www a www 3 O 9 N f k., o www L, w\w www o, www A www G www www www www ww w www .www n" NNN mvENToR ATTORNEY Sept. 12, 1944. u. A. wHlTAKr-:R 2,357,850

CIGARETTE DETECTING AND CORRECTING APPARATUS Filed April 2, 1941 8 Sheets-Sheet 7 ATTORNEY Sept. 12, 1944. u. A. wHrTAKER CIGARETTE DETECTING AND CORRECTING APPARATUS Filed April 2, 1941 8 Sheets-Sheet B INVENTOR UNCAS A.WHITAKER ATTORNEY Patented Sept. 12, 1944 UNITED CIGARETTE DETECTING AND CQRRECTING APPARATUS Uncas A. Whitaker, Brooklyn, N. Y., assignor to American Machine & Foundry Company, a corporation of New Jersey Application April 2, 1941, Serial No. 386,487

16 Claims.

This invention relates to the manufacture of cigarettes. An important object of the invention is the detection of cigarettes varying from a predetermined standard, and the rejection or segregation of the cigarettes which do not con form to the desired standard. In this connection one of the main objects of the invention is to provide an apparatus for determining variations in the density of a cigarette rod.

A further object is to associate in a cigarette machine with the detecting apparatus, mechanism controlled from said apparatus for ejecting or segregating the cigarettes severed from the portions of the cigarette rod which do not conform to a. predetermined standard. Still another object is to provide in a. cigarette machine mechanism controlled from apparatus for electrically detecting the density of the cigarette rod, for varying the operation of the tobacco feed of the machine to inc-rease or diminish the rate at which tobacco is delivered to the cigarette rod-forming mechanism. The mechanism for segregating the sub-standard cigarettes and the mechanism for controlling the tobacco feed may be associated on the same cigarette machine, together with their respective apparatuses for determining the density of the cigarette rod.

The detecting apparatus of the tobacco feed controlling mechanism may be arranged to determine the density oi the stream of tobacco being advanced into the rod former for enfoldment within the cigarette paper to form the cigarette rod. In this connection another object of the invention is to deliver a stream of tobacco between opposed members at a rate such that a column of tobacco of uniform density will be formed `between said members, and to determine the length of said column and control the tobacco feed to maintain a predetermined volume of tobacco in said column so that the end of said column will remain at a predetermined position between said members.

The condition of the cigarette rod may be determined by electrostatic apparatus comprising spaced pick-up plates sufficiently spaced to admit a cigarette rod therebetween and connected to a. high frequency electric circuit which will be affected by the characteristics of the section of the cigarette rod between plates so as to vary the current in the circuit. In accordance with the invention, variations in this current are utilized to measure variations from normal in the density of the rod. The circuit may be adjusted by inserting a cigarette conforming to a predetermined standard between the pick-up plates and adjusting the current to respond to variations in the cigarette rod from said standard. It is .believed that variations in this circuit result mainly from variations in the moisture content of the tobacco in the rod. Thus i. a cigarette rod having a predetermined moistute content is advanced past the plates, underiilled or overlled portions thereof will contain greater or less moisture and correspondingly vary the characteristics of the circuit and the current flowing therein.

By this means it is possible to detect underfilled or overfilled spots which constitute a minor fraction of a. cigarette length. Moreover no mechanical feelers are used, Whose inertia must be overcome 'before discrepancies in the cigarette rod will be detected. It may be noted that mechanical feelers, which have been used heretofore, do not give a true determination of the condition of the cigarette, inasmuch as they tend to modify or compress the cigarette being tested, and also due to the relatively great linear speed of the rod and this inertia of the feelers they are not sensitive to short low or high spots a fraction of a cigarette length long but tend to ride over such spots without responding to them.

Since the moisture content of the tobacco constitutes an index of the density of the tobacco, as it is proportional to the weight of a given mass of tobacco of uniform moisture content, variations ln the density of the cigarette rod, and in the stream of tobacco fed into the rod former, may be detected and utilized to eiect a segregation of defective cigarettes and/or control the feeding of the tobacco to the rod former.

It is noted that the moisture content of well prepared and mixed tobacco is ordinarily quite uniform throughout a given mass at a given time, due it is believed, in part, to the fact that tobacco is very hygroscopic and in the mass relatively dry parts tend to absorb moisture and damp parts to give up moisture until the moisture content of adjoining portions is substantially uniform.

With these and other objects not specifically mentioned in view the invention consists in certain constructions and features hereinafter fully described and then specifically set forth in the claims hereunto appended.

In the accompanying drawings which form a part of this specification and in which like characters of reference indicate the same or like parts:

Fig. 1 is a side elevation of a continuous rod cigarette machine in conjunction with a capacicontrol arm 6l and continuing to travel will raise said control arm in an upward direction. Control arm 64 is pivoted to a stud 65 held by a bracket 66, mounted on one end of bed 21. Said control arm is also provided with a hook-shaped lock lug 61 normally held in engagement with a lock pin 60 by means of a tension spring 69 (Figs. 2 and 4). Lock pin 68 is held by an arm 10 to which is secured another arm 1I forming a bellcrank 12 pivoted on a stud 13 held by a suitable lug of bearing bracket 26. The free end of arm 1I carries a contact plate 14 (Figs. 2 and 4) which, when bell-crank lever 12 is locked by means of arm 54, hangs with but little clearance directly above a crank pin 15 of a crank shaft 16 supported by a bearing lug 11 of bracket 26. Crank shaft 16 is continuously rotated by means of a gear 10 fastened thereon and meshing with gear 35 on shaft 25. To arm 1I is pivoted one end of a. connecting rod 19. 'I'he other end of the same is pivoted to the arm I1 which supports the rotating ejector rods I5 described heretofore. A tension spring (Fig. 2) anchored to arm I1 and bracket I9 urges arm I1, as well as arm 1I, downward; but as long as lug 61 of arm Bl remains in engagement with lock pin 6B, this movement is checked. When the projecting end of one of the released plungers l0 liftsl arm 64 and thereby disengages lug 61 from lock pin 68, the plate 14 of arm 1I is brought in contact with crank pin 15 and follows the rotating crank pin, thus also imparting oscillating motion to arm I1 with the result that the rotating ejector rods I are lowered into position to sweep oi the cigarettes L being delivered at that moment from the guide channel 46 to the collector belt 41. The cigarette to be ejected is caught by the ejector rods I5 in mid air and thrown into an ejector chute formed by a pair oi guide plates 8| and 62 (Figs. 1 and 2) which are both attached to the bearing bracket I9.

The cigarette cut-oi mechanism C (Fig. l) which is driven through shaft B3 and a pair of spiral gears 04 from the main shaft 34, is timed with respect to the ejecting and timing mechanisms in such a manner as to deliver in the path of the ejector rods the particular cigarettes which cause disturbance oi' the balance of the electrostatic detector control unit while passing through the detector box D. Since the projecting end of the released plunger 40 continuously moves with the timing disk 38 in anti-clockwise direction, said plunger end remains in contact with arm 64 only for an interval sufcient to release bell crank 12. As soon as the released plunger travels away from said arm 64, the lug 61 re-engages with the lock pin 68 oi' arm 10 and thereby arrests arm 1I in a position at which plate 14 will clear the continuously rotating crank pin 15, to maintain the rotating ejector rods I5 out of the path of the stream of cigarettes which are being delivered to the collector belt 41.

In order to reset any released plungers before completion of their cycle, the projecting ends of the same after leaving arm 64 contact an angularly mounted resetting plate 85 (Figs. 2 and 3) and are gradually pushed back until the corresponding lock finger M snaps behind the socket portion 4I of the plunger, keeping said plunger retracted until said finger is tripped again.

In order to prevent damage to the ejector mechanisms in case the cigarette machine is turned backward by hand, the shaft 30 connecting the ejector mechanism with the main drive, is equipped with a one-way clutch 90 (Fig. 4)

in which a spring-pressed pin 9| engages with a spiral jaw collar S2 allowing shaft 30 to be driven one way only. One section 30a of shaft 30 is fastened to clutch while the other section 30h carries the spiral jaw collar 02.

Referring to Fig. 6, there is illustrated an electro-static detector control circuit in which the capacity between the detector plates 20I is balanced against the capacity of a variable (air) condenser 202. The detector circuit may be of the so-called universal, or A. C.D. C. type, in which the power from the line passes through a half-wave rectier tube 203 and a filter consisting of choke coil 204 and condensers 205. 'Ihe cathode heaters H of the various tubes are connected in series across the line in the usual manner (not shown), but it will be understood that the cathodes may be directly heated if desired.

The tuned plate coil 206 of the high-frequency oscillator tube 201 is center tapped, with the tap connected to the positive output terminal of the filter. Tuned grid-coil 208 is inductively coupled to the plate coil, and also capacitatively through a small condenser 209. Resistance 2I0 and condenser 2II are the usual grid leak and condenser for limiting the oscillation of tube 201 to the straight portion of its plate-current curve. When the tube 201 oscillates, equal high frequency currents, degrees out of phase, are generated on the two ends of coil 206.

The tuned coil 2I2 is connected in the grid circuit of the high frequency amplifier tube 2I3, which is of the pentode type. Coil 2I2 is tuned to the same frequency as the oscillator and is coupled to both sides of coil 206, through condenser 22 and detector plates 20|. Condensers 2H are inserted in the leads to plates 20I to insulate the plates from line or D. C. power. If the capacity of condenser 202, and the capacitance between plates 20I is balanced, no voltage will be impressed on coil 2I2.

A tuned high frequency transformer 2I5 oouples the plate circuit of amplifier tube 2I3 to the grid circuits of indicator tube 2I6 and output tube 2I1, through condensers 224. Indicator 2I6 is of the type in which a triode is combined with an electron-ray indicator. It is biased to zero shadow angle by resistor 2I0 in series with thecathode. Resistor 235 is the grid-leak. The anode plate resistor 2I0 is by-passed by a condenser 220. Thus the triode acts as a biased detector, and the whole tube 2l6 as a zero-indicator.

Output tube 2I1 is a gas-illled, grid-controlled rectifier. By means of battery 22| and

resistors

222 and 223, the grid is normally maintained at a sufficiently negative bias, to prevent the ow of plate current. When the H. F. output of transformer 2I5, which is connected to the grid of tube 2I1 through condenser 224, exceeds a certain limit, plate current starts to tiow, and, once started, the grid has no further control over it, and it can only be stopped by interruption of the plate current. For this purpose the relay 225 shown in Fig. 5 is connected in series with the plate of tube 2I1, to be energized and thereby attract the armature 50 and open the normally closed contact 226. Resistor 221, in multiple with magnet 225 and contact 220 is of such high value that the current through it is insulcient to maintain ionization of the gas in tube 2I1 after contact 226 opens. Push button 226 is for manual interruption of the plate current. A thermal time delay unit 229 prevents the flow of plate current in tube 2|'| till the cathode is at full emission temperature.

A variable rheostat 230 in series with a fixed resistor 23| and the cathode of amplifier tube 2|3 regulates the degree o! amplification of tube 2|3. The shield 235* around the oscillator coils 203 and 20B, the shield 236 around grid coil 2I2, the shield 231 around transformer 2 I 5 and the shields 230 around the leads to plates 20| are connected to the negative side of the filter through condensers 232, which by-pass any H. F. currents, but reduce feed-back and interference from surges in the power line. Condenser 233 is connected across the power line, and condenser 234 between the negative side of the filter and ground, for the same purpose.

The operation of the circuit is as follows:

After all tuned circuits are aligned to the same frequency (500,() cycles/second, has been found to be suitable) condenser 202 is adjusted till zero output is obtained from the amplifier 2|3, with a cigarette of the desired density between plates After that, whenever either an underfilled or an overi'llled spot on the cigarette rod passes between the plates, an unbalance is caused which results in a high frequency voltage being im.- posed on the grid of tube 2H, and of tube 2I6. If this H. F'. voltage is of suflicient amplitude, it will "trip tube 2|1 and energize relay 225. The curvature 50 of relay 225, on being attracted during energization of the latter, opens contact 226 and thereby breaks the plate current of tube 2 the armature 50 being mechanically locked in its upper position and held there till reset mechanically by mechanism described above.

The spread between the upper and lower reject limits is determined by the degree of amplification, and by the amount of negative grid bias on tube 2H. The less the amplification and the greater the bias, the wider the spread becomes. By adjusting the circuit for a wide spread, and adjusting the balancing condenser 202 to zero output for a somewhat higher density than the desired average, the unit can be made more sensitive for underfilled than overiilled spots, or the opposite way.

Since in manufacturing of cigarettes the average density of the cigarette rod may be of even greater importance than the detection of overillled or underfilled spots, the cigarette machine may also be equipped with an electrostatic control of the tobacco feed, with the object of increasing or decreasing the amount of tobacco fed into the cigarette rod. For this purpose the cigarette rod R passes between a pair of detector plates (Fig. 7) which may be supported within a detector box Z (Fig. l) conveniently attached to the bed of the cigarette machine. Said plates 30| by means of wires X are connected to an electrostatic control unit supported in box 300. The circuit of said tobacco feed control unit is disclosed in Fig. l and has many points in common with the circuit for the detector unit previously described. The detector plates 30|, however, are of much greater length, axially of the cigarette rod, than plates 20|. The capacity between plates 30| may be balanced against the capacity of an adjustable air condenser 302, as in the case of the circuit shown in Fig. 6 which is balanced against the adjustable condenser 202.

The circuit of this detector unit is also of the so-called universal, or A. C.D. C. type, in which the power from the line passes through a halfwave rectifier tube 303 and a filter consisting of choke coil 304 and condensers 305. The cathode heaters H3 of the various tubes are connected in series across the line in the usual manner (not shown), but it will be understood that the cathodes may be directly heated if desired.

The tuned plate coil 306 of the high-frequency oscillator tube 301 is center tapped, with the tap connected to the positive output terminal of the filter. Tuned grid-coil 300 is inductively coupled to the plate coil and also capacitively, through a small condenser 309. Resistance 3I0 and condenser 3|| are the usual grid leak and condenser for limiting the oscillation of tube 301 to the straight portion of its plate-current curve. When the tube 301 oscillates, equal H. F. voltages, deg. out of phase, are generated on the two ends of coil 306.

The tuned coil 3|2 is connected in the grid circuit of the H. F. amplifier tube 3|3, which is of the pentode type. Coil 3|2 is tuned to the same frequency as the oscillator and is coupled to yboth sides of coil 306, through condensers 3M and detector plates 30|. Condensers 3M are inserted in the leads to plates 30| to insulate the plates from line or D. C. power. If the capacity of condenser 302, and the capacitance between plates 30| is balanced, no voltage will be impressed on coil 3|2.

A tuned H. F. transformer 336 couples the amplifier tube 3I3 to the double-diode detector tube 33T and indicator tube 3I6. The tuned primary of transformer 336 is connected in the plate circuit of tube 3I3. The tuned secondary is divided into two equal parts, the H. F. voltages across which are rectied separately by the two sections of detector tube 331, Condensers 333 and resistors 330. Condenser 340 is a by-pass for H. F. current between the two halves of the secondary of transformer 336. The two rectified voltages appearing across Condensers 338 are impressed on the grids of the two output tubes 3H and 3||a.. The grid bias of these two tubes is controlled individually by two potentiometers 34| and 34Ia -connected in series across 0" battery 32|. The polarity of the rectifier-connections is such that when the H. F. voltage increases, the grid of the light" output tube 3|1 becomes more negative, and that of the heavy" output tube 3|1a less negative. One side of the secondary of transformer 336 is also coupled to the grid of the indicator tube 3|6 through condenser 320.

Indicator tube 3|6 is of the type in which a triode is combined with an electron-ray indicator. It is biased to Zero shadow angle by resisto] 3|0 in series with the cathode. Resistor 335 i: the grid-leak. The triode plate resistor 3|9 is by-passed by a condenser 320. Thus the triode acts as a biased detector, and the whole tube 3I6 as a zero-indicator.

Output tubes 3|`| and 3I`|a are gas-filled, gridcontrolled rectiers. Potentlometers 30| and 34m are adjusted to a point where, with normal output from the detector tube 331, the grids of tubes 3Il and 3|`|a are both at a suficiently negative potential to prevent the ilow of plate current. If the output from the detector tube 331 increases, the grid of the heavy" tube 3|`| becomes less negative. At a certain point, plate current starts to flow in this tube, and, once started, the grid has no further control over it, and it can only be stopped by interruption of the plate current. The coil of a relay 325 similar to that shown. in Fig. 5 is connected in series with the plate of tu-be 3I'I. It the output from the detector tube 331 decreases, the grid of the "light" tube 3|la becomes less negative, till plate current starts to ow. Another relay 325a is connected in the plate circuit of this tube 3|1a. Push button 320 is for manual interruption of the plate current in both tubes 3H and 3|1a. A thermal time delay unit 320 prevents the flow of platt` current in tubes 3H and 3|la till the cathodes are at full emission temperature. Switch 342, which also interrupts the plate current in both tubes 3|1 and 3|`|a is controlled by a cam 343. i

A variable rheostat 330 in series with a fixed resistor 33| and the cathode of amplier tube 3|3 regulates the degree of amplification of tube 3|3. The shields around the oscillator coils 306 and 300, grid coil 3|2, transformer 336, and around the leads to plates 30| are connected to the negative side of the filter through condensers 332, which by-pass any H. F. currents, but reduce feed-back and interference from surges in the power line. Condenser 333 is connected across the power line, and condenser 334 between the negative side of the filter and ground, for the same purpose.

The operation of the circuit is as follows:

After all tuned circuits are aligned to the same frequency (500,00 cycles/second has been fourd to be a suitable frequency) condenser 302 is adjusted till zero output is obtained from the amplifier, as indicated by tube 3I6, without any cigarette between plates 30|. Then with a cigarette of the desired average density between the plates 30| and potentiometer 330 set for maximum. amplification, the potentiometers 34| and 34|a are adjusted just below the tripping points of tubes 3H and 3l1a. When set this way, heavy tube 3|1 will trip for any cigarette heavier than this average, and light tube 3|1a for any cigarette lighter than this standard. The spread" between the upper and lower limits can be increased by reducing the amplification with potentiometer 330. Condenser 302 does not necessarily have to be set for balance without any cigarette between plates 30|, but must be set for balance outside the limits between which it is desired to control the feed. If adjusted for balance above the maximum density, the desigrations light and heavy should be interchanged.

The two relays 325 and 325a control the movements of an armature 344, centrally pivoted at a point between the two magnets. Said armature 344 is normally held in a balanced or neutral position by means of a pair of light springs 350 each of which is anchored to a stationary pin 35|. Therefore armature 344 can only make contact when attracted by one or the other relay. If the light magnet 325a is energized, contact 345 closes, and if the heavy" magnet 325 is energized, contact 346 closes, but the two contacts can never close at the same time.

Contacts

345 and 346 control a reversing motor 352 on whose shaft is mounted a pinion 353 driving a gear 354 (Fig. 7) on the regulating screw shaft 355 of a variable speed transmission 356, such as the Reeves drive fully described in the patent granted to Wilford J. Hawkins on June 28, 1932, No. 1,864,728, through which the motor 351 drives the tobacco feed F. The turning of the motor 352 in one direction will increase, and in the other direction will decrease, the rate of feed of tobacco T being showered on cigarette paper P by a proportional amount. From the Reeves drive 356 is driven the tobacco feed F by means of a chain 350. The cigarette paper is wrapped about the tobacco deposited thereon to form a continuous cigarette rod by means of a rod former U (Fig. 1). the seams of said rod being pasted by a pastel' V and sealed by a sealer S.

Cam 343 is driven continuously from the main drive of the machine (not shown). When one of the tubes 3I1 or lilla is tripped, energizing its corresponding relay, the latter remains energized, continuing to change the rate of tobacco feed, until cam 343 opens switch 342 and breaks the plate current. The timing of cam 343 is such that switch 342 remains open for a suilicient length of time for the effects of the correction to become noticeable between plates 30|. If the correction was insufficient, a second correction in the same direction will take place when switch 342 recloses.

With reference to Fig. 8, the drawings disclose a pair of detector plates 400 placed above and below the tobacco guide channel which, in this instance, is formed by means of a rodiorming tape 40| and a top belt 402. The tobacco TA is fed from a tobacco feed FE into a tobacco feed channel formed by an inclined bottom belt 403 and a top belt 404 having an inclined run coasting with the upper run of belt 403 to deposit the tobacco stream ST on to a paper web P which rests upon and travels with the rod-forming tape 40|. The tobacco feed FE has a shaft 405 carrying a sprocket 406 whereby the feed is driven by a chain 401 from a variable speed transmission of the same type and construction as the one disclosed in Fig. '7. The detector plates 400 by means of wires WI are connected with exactly the same circuit of an electrostatic control unit for a tobacco feed as disclosed in Fig. 7, in this case the detector plates 400 replacing plates 30|. As disclosed in Fig. 8, a thin stream of tobacco ST, or a stream of little density, is fed fast to the slower moving channel formed by belts 40| and 402 with the object of building up a tobacco column CO of greater volume and density. It is of course very desirable and important to keep this tobacco column which builds up between belts 40| and 402 at a uniform length, and it is therefore essential to control the density and amount of tobacco present in stream ST. As illustrated in Fig. 8, the tobacco stream ST passes in between the two detector plates 400 to build up the larger column CO. If too much tobacco is fed, the latter will cause said column to increase in length until upon reaching the detector plates 400, it unbalances the circuit of the electrostatic control unit which in turn operates the variable speed drive. Thus in this case the rate at which tobacco is delivered by the tobacco feed is decreased.

In the construction shown in Fig. 8, the tobacco will be always overfed a little in order to form a full column of tobacco at all times.

Another important feature of the invention disclosed in Fig. 8 is the speed with which the change of the tobacco flow can be effected. Heretofore, the

inclined feed belts

403 and 404 were driven from the driving mechanism of the cigarette maker, requiring a considerable time before a change of the tobacco feed was noticeable in the tobacco stream or cigarette rod. By driving said belts directly from tobacco feed drive shaft 405, a change of the speed of the tobacco feed will also immediately change the speed of the

feed belts

403 and 404,. Belt 403 is supported by an idler roller 4|0 and driven by a pulley 4H mounted on a shaft 4|2 and carrying a bevel gear 4|3 meshing with a bevel gear 4|4 mounted on a vertical shaft 4|5 held by a bearing bracket 4|6 attached to the housing of the tobacco feed FE. Shaft 4|5 is driven by a bevel gear 4|`| meshing with bevel gear 4|0 which is mounted on the feed drive shaft 405. Belt 404 runs over a pair of guide rollers 4I! and an idler roller 420 and is driven by a roller or pulley 42| mounted on a shaft 422 driven by means of a pair of bevel gears 423 from a shaft 424 supported in suitable bearings of a bracket 425. To shaft 424 is fastened a gear 426 which through an intermediate gear 421, is driven by a gear 428 attached to the feed driving sprocket 406 on shaft 405.

Another important feature lies in the use of the top guide belt 402 which, together with belt 40| forms the slower moving guide channel in which the heavier tobacco column CO is built up. Said belt 402 is not only a guide belt but also acts as a retainer, its more or less rough surface not allowing the tobacco to slide, thus assuring a firm grip on the tobacco column and a positive movement of the same. Said belt 402 runs over a pair of guide rollers 430 and an idler roller 43| and is driven by means of a roller 432 mounted on a shaft 433 which is driven, lust as belt 40| from the main drive of the cigarette maker. By supporting all

rollers

430, 43| and 432 on an adjustable bracket (not shown) the channel may be adjusted to different heights.

Referring to Figs. 9 and ll, a cam-operated interrupting switch 500 may be arranged in the circuit shown in Fig, 1l to bridge the contacts 50| in the lead W2 from the thermal time delay 229 to the cathode of the tube 2I1 (Fig. 1l); and switch 500 will be arranged in this lead in addition to the manual switch 220. The switch 500 will be timed to make contact during the passage of sections of the cigarette rod corresponding to the ends of the severed cigarettes. The leads WI which are shown connected in Fig. 9 to the detector plates in detector box D will be connected to the wires W of the detector control unit in the box 200 (Fig. l). Switch 500 is arranged to bridge the contacts 50| in lead W2 and is mounted on a rod 502 provided with a cam follower 503 engaging a cam 504 on a shaft 505. On the latter is mounted a spiral gear 50B driven from the spiral gear 501 mounted on the shaft 63 shown in Fig, 1. Thus the switch will be raised to break the detector control circuit except during the passage of sections of the cigarette rod corresponding to the cigarette ends. With this modified construction, under-filled or overfllled spots occurring at intervals corresponding to the sections at which the cigarette rod is severed will be detected. and the corresponding severed cigarettes which have underfilled or overillled sections adjacent their ends Will be rejected.

In Fig. l1 there is shown the complete detector circuit, including the modified construction illus trated in Fig. 9. The circuit illustrated in Fig. il is identical in every detail with that shown in Fig. 6 except for the addition of the cam operated switch 600 which has been described above. Therefore description of the parts |202-30 is deemed unnecessary. The parts referred to by characters |202-36 correspond to the parts 202-236 respectively of Fig. 6.

In Fig. l there is shown a modified detector control circuit wherein the capacity between the detector plates 60| surrounding the cigarette rod R is balanced against the capacity between another pair of detector plates 600 also surrounding the cigarette rod and suitably spaced from the plates 60|. The circuit of this detector unit may also be of the so-called universal or A. C,D, C. 76

type. similar to that shown in Fig. 6, in which the power from the line passes through the half-wave rectifier tube 603 and a lter" consisting of choke coil 604 and condensers 605. The cathode heaters H of the various tubes are connected in series across the line in the usual manner (not shown), but it will be understood that the cathodes may be directly heated if desired.

The tuned plate coil 603 of the high-frequency oscillator tube 601 may be center tapped, if the detector plates 600 and 60| are of the same length, but the plates 600 are preferably longer than the plates 60|, for a purpose hereinafter described, and a tap connected to the coil 606 leads to the positive output terminal of the lter consisting of the choke coil 604 and the condensers 605. Tuned grid-coil 00B is inductively coupled to the plate coil, and also capacitatively through a small condenser 609. Resistance 6|0 and condenser 6|| are the usual grid leak and condenser for limiting the oscillation oi' tube 601 to the straight portion of its plate-current curve. When the tube 601 oscillates, equal high-frequency currents degrees out of phase, are generated on the two ends of coil 606.

The tuned coil 6|2 is connected in the grid circuit of the high frequency amplifier tube 6|3, which is of the pentode type. Coil SI2 is tuned to the same frequency as the oscillator and is coupled to both sides of coil 606 through condenser 602 and detector plates 60| respectively, and the coil 6|2 is additionally coupled to the coil 606 through the plates 600. Condensers 6|4 and 6|4a are inserted in the leads to plates 60| and 600 respectively, to insulate the plates from line or D. C. power, and an additional condenser |i|4 is inserted in the lead from the plates to the coil 6|2 for a similar purpose. Since the plates 600 are longer than the plates 60|, the capacity between plates 600 is greater than the capacity between plates 60|, and the tap on oscillator coil 606 is displaced from the center to one side thereof to an extent suflicient to make the H. F. voltages across the two sides of coil 606 inversely proportional to the capacities between plates 600 and 60|. As long as this balance is maintained, no H. F. is impressed on coil 6|2. This balance is not changed by the presence of the rod R between the condenser plates as long as the density of the section of the rod between plates 60| is the same as that between plates 600. Condenser 602 is of small capacity and serves only to maintain exact balance.

A tuned high frequency transformer 6|5 couples the plate circuit of amplifier tube 6|3 to the grid circuits of indicator tube 6 I6 and output tube BIT, through condensers 624. Indicator 6|6 is of the type in which a triode is combined with an electron-ray indicator. It is biased to zero shadow angle by resistor 6|B in series with the cathode. Resistor 635 is the grid-leak. The anode plate resistor 6| 9 is by-passed by a condenser 620. Thus the triode acts as a biased detector, and the whole tube 6|6 as a zero-indicator.

Output tube 6|1 is a gas-lled, grid controlled rectifier. By means of battery 62| and resistors 622 and 623, the grid is normally maintained at a sufficiently negative bias, to prevent the flow of plate current. When the H. F. output of transformer 6 5, which is connected to the grid of tube 6|1 through condenser 624, exceeds a certain limit, plate current starts to flow, and, once started, the grid has no further control over it, and it can only be stopped by interruption of the plate current. For this purpose the relay 625.

similar to the relay III shown in Fig. 5. is connected in series with the plate of tube Bl'l, to be energized and thereby attract the armature III, which is similar to the armtaures l shown in Fig. 5, Vand open the normally closed contact SII, whose constructionfi's identical with that of contacts 228,- Fig. 5. Resistor 021. in multiple with magnet $25 and contact |28 is of such high value that the current through it is insuilicient to maintain ionization of the gas in tube Bl'l after contact 023 opens. Push button l!! is for manual interruption of the plate current. A thermal time dely unit 820 prevents the flow of plate current in the tube 8H till the cathode is at iull emission temperature.

A variable rheostat 830 in series with a iixed resistor GII and the cathode oi amplifier tube 6i! regulates the degree of amplification of tube lill. The shield 6354 around the oscillator coils B08 and 608the shield 03B around grid coil H2, the shield B31 around transformer BIE and the shields around the leads to plates |00 and 80| which are similar to the shields 238 (Fig. 6) are connected to the negative side of the filter through condensers 632, which by-pass any H. F. currents, but reduce feed-back and interference from surges in the power line. Condenser 633 is connected across the power line, and condenser 634 between the negative side of the filter and ground, for the same purpose.

'I'he operation of the circuit is as follows:

All tuned circuits are aligned to the same frequency (500,000 cycle/second, has been found to be suitable). Plates 60| may be of i/s inch or any other suitable length, and plates 600 may be of the same or greater length. If the plates Bll are substantially longer than plates 60|, there will be rejection whenever a short defect, such as a hole or hard spot, passes between the plate 60|, an unbalance being caused which results in a high frequency voltage being imposed on the grid of tube SI1. and of tube BIB. If this H. F. voltage is of suilicient amplitude, it will trip" tube 6H and energize relay B25. The armature B50 of relay 625, on being attracted during energization of the latter, opens contact 62B and thereby initiates the operation of the ejector mechanism shown in Fig. 2 and breaks the plate current of tube SI1, the amature being mechanically locked in its upper position and held there till reset mechanically by the mechanical locking mechanism described above. But no rejection takes place as long as the rod is uniform, regardless of whether it is hard or soft. The principal advantage derived from this arrangement is that it is not aii'ected by gradual changes in density and/or moisture content, which affect all parts of the rod equally, and in other qualities of the tobacco which change the capacity effect of the rod without a corresponding change in its density, and which aiect all parts of the rod equally.

I have referred to the plates 20| and 6M as condenser plates and have referred to a capacitative coupling between said plates which varies the current in the circuit because of the variations in the rod operating adjacent or between them. Actual test with the construction disclosed shows there is a variation in current but it, is not possible to be certain as to what are all the factors which cause this current change as a result of rod variations. Therefore, I do not wish to be confined to any particular theory as to how the current is varied in the circuit as a result of the coaction of these plates and the the rod.

For purposes of illustration I have shown spe ciiic embodiments of my invention. However, it will be apparent to those skilled in the art that changes andmodications can be made therein without departing from the true spirit of my invention or the scope of the appended claims.

What is claimed is:

l. In a cigarette machine, the combination with cigarette rod-forming mechanism, of a device for severing cigarettes from the cigarette rod. and mechanism responsive to the condition of the cigarette rod at a section ahead of said device for segregating the severed cigarettes which do not conform to a predetermined standard.

2. In a cigarette machine, the combination with cigarette rod-forming mechanism operating to form and continuously advance a cigarette rod, of a cutoff for severing cigarettes from said cigarette rod, a device for detecting defective sections of the cigarette rod, and mechanism controlled by said device for displacing the defective cigarettes horizontally from the path of the cigarettes issuing from said cutoi in alignment with the cigarette rod.

3. In a cigarette machine, the combination with mechanism for forming a cigarette rod, of a cutoii for severing cigarettes from the cigarette rod, a device responsive to an underfilled or overiiiled section of cigarette rod, and single means controlled by said device for segregating the cigarettes containing the underiilled or overlled portion of the cigarette rod.

4. In a cigarette machine, the combination with mechanism for forming a cigarette rod, of a cutoff f or severing cigarettes from the cigarette rod, a device responsive to an uncleriilled or overiilled section of cigarette rod, and mechanism controlled by said device for segregating the cigarettes containing the underfilled or overfllled portion of the cigarette rod, said device being adjustable to vary the limits between which an underiilled or overfilled portion of the cigarette rod will suiciently affect said device to cause segregation of the cigarettes severed irom the abnormal portion of the cigarette rod.

5. In a cigarette machine, the combination with mechanism for forming a cigarette rod, of a, cutoii for severing cigarettes from the cigarette rod, a device responsive to an underlled or overfilled section of cigarette rod, and mechanism controlled by said device for segregating the cigarettes containing the undertllled or overlled portion of the cigarette rod, said device being biased to be more sensitive to one type of abnormal portion than to the other type of abnormal portion.

6. In a cigarette machine, the combination with mechanism for forming a cigarette rod, of a cutoi for severing cigarettes from the cigarette rod, a device responsive to an underiilled or overlled section of cigarette rod, and mechanism controlled by said device for Scgregatlng the cigarettes containing the underlled or overlled portion of the cigarette rod, said device being constructed and arranged to be more sensitive to an overillled portion oi the cigarette rod than to an underlled portion thereof.

'7. In a cigarette machine, the combination with mechanism for forming a cigarette rod, oi a cutoil' for severing cigarettes from the cigarette rod, a device responsive to underlled and overlled sections of the uncut cigarette rod, and single means controlled by said device for performing an operation on cigarettes severed from underillled and overlled portions of the cigarette rod.

8. In a cigarette machine, the combination with mechanism for forming a cigarette rod, a cutoff for severing cigarettes from the cigarette rod, a device responsive to the density of an overillled section of the cigarette rod. and mechanism controlled by said device for performing an operation on the cigarette containing the overnlled section of the cigarette rod.

9. In a cigarette machine, the combination with mechanism for forming a cigarette rod, a cutoff for severing cigarettes from the cigarette rod, a device responsive to the density o! an undertllled section of the cigarette rod, and mechanism controlled by said device for performing an operation on the cigarette containing the underillled section of the cigarette rod.

10. The combination with a plurality ot condensers adapted to permit passage of a cigarette rod therethrough and spaced with respect to each other along the length of the cigarette rod, of an electric circuit connected to said condensers and responsive to diilerences in the capacitative coupling of one of said condensers with respect to another of said condensers due to differences in the density of the sections of the cigarette rod therein, and a device controlled by said circuit for detecting diierences in the density of one section of the cigarette rod, with respect to a different section thereof.

1l. In a cigarette machine, the combination with mechanism for forming a cigarette rod, of means for detecting diil'erences in density between one section of a cigarette rod and a different section thereof, a cutoff for severing ciga rettes from the cigarette rod, and mechanism controlled by said means for segregating cigarettes upon detection of diierences in density between said different sections of the cigarette rod.

12. The combination with a device responsive to variations in the density of one section of a cigarette rod. of a device responsive to variations in the density of a diilerent section of the cigarette rod, and control mechanism connected to said devices and responsive to diierences in density between the diiierent sections of the cigarette rod to which said devicesare responsive.

13. The combination with a device responsive to variations in the density of a short section of a cigarette rod, of a device responsive to variations in the density of a longer section o! the cigarette rod, and control mechanism actuated by said devices and responsive to differences in density between the short and longer sections of the cigarette rod to which said devices are responsive.

14. In a continuous rod cigarette machine having a cutoil' for severing the cigarette rod into cigarette lengths. the combination with means for detecting abnormalities in the cigarette rod prior to severance, of means controlled by said detector means for distinguishing the individual severed cigarettes resulting from severance of the abnormal portions of the cigarette rod.

15. The combination with means for continuously advancing a cigarette rod and severing cigarettes therefrom, of mechanism for segregating from the severed cigarettes those cigarettes which have variations from a predetermined standard at their ends, and means controlling said mechanism and setting it into operation for segregation of cigarettes having sub-standard density at their ends, said controlling means including an electric circuit and a condenser in said circuit which is responsive to variations in the moisture content of tobacco, and an electrical control device connected to said circuit for setting said mechanism into operation.

16. In a cigarette machine, the combination with mechanism for forming a cigarette rod and severing cigarettes therefrom, of a device for detecting variations in the condition of the cigarette rod only at sections thereof adjacent the points where the rod is subsequently severed, and mechanism controlled by said device for segregating cigarettes having variations in the condition of their ends from a predetermined standard.

UNCAS A. WHITAKER.

CERTIFICATE OF CORRECTION.

Patent No. 2,557,860.

September l2, 19h14..

UNCAS A. WHITAKER.

It is'hereby certified that error appears in the printed specification of the above nunbered patent requiring correction as follows: Page 7, second column, line 52, claim 2, before the word "horizontally" insert --s'evered from the defective sections of the cigarette rod; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this llith dey of Noveni'ier, A. D. 19h14..

(Seal) Leslie Frazer Acting Commissioner of Patents.

sensitive to an overillled portion oi the cigarette rod than to an underlled portion thereof.

UNCAS A. WHITAKER.

CERTIFICATE OF CORRECTION.

Patent No. 2,557,860.

September l2, 19h14..

UNCAS A. WHITAKER.

Signed and sealed this llith dey of Noveni'ier, A. D. 19h14..

(Seal) Leslie Frazer Acting Commissioner of Patents.