US2534268A

US2534268A - Washing machine cylinder balancing apparatus

Info

Publication number: US2534268A
Application number: US673680A
Authority: US
Inventors: Leo M Kahn; Ellner Edwin
Original assignee: Individual
Current assignee: Individual
Priority date: 1946-05-31
Filing date: 1946-05-31
Publication date: 1950-12-19
Anticipated expiration: 1967-12-19

Description

Dec. 19, 1950 KAHN ETAL 2,534,268

WASHING MACHINE CYLINDER BALANCING APPARATUS Filed May 31, 1946 5 Sheets-Sheet l SUPPLY POWER SELECTOR DISTRIBUTOR AMPLIFIER DISTRIBUTOR j In 30:90

ATTORNEY Dec. 19, 1950 L. M. KAHN :rm. 2,534,268

WASHING MACHINE CYLINDER BALANCING APPARATUS Filed May 31, 1946 5 Sheets-Sheet 2 Dec. 19, 1950 Filed May 31, 1946 L. M. KAHN ETAL WASHING MACHINE CYLINDER BALANCING APPARATUS 5 SheetsSheet 3 T0 ViBRATlON PICKUP CYCLE FT F7 I x7 I J7 1T5 L FIRING i l I VO/LTAGE 1 FLE -"LEL /5b gmwmpw;

l r I Dec. 19, 1950 L. M. KAHN rm 2,534,268

WASHING MACHINE CYLINDER BALANCING APPARATUS Filed Bay :51, 1946 5 Sheets-Sheet 4 PF 'Fl I FIIRING I a o K 0 h ll By fduna c %%-Ev Dec. 19, 1950 M. KAHN ETAL wmmc ncamz CYLINDER BALANCING APPARATUS Filed lay 31, 1946 5 Sheets-Sheet 5 Firs--11.-

Patented Dec. 19, 1950 WASHING MACHINE CYLINDER. BALANCING APPARATUS Leo M. Kahn and Edwin Ellner, New York, N. Y.; said Ellner assignor to said Kahn Application May 31, 1946, Serial No. 673,680

24 Claims.

. 1 This invention relates to damp drying systems for laundry machines wherein the extraction of washing fluid from the washed articles is effected through high speed rotation of a perforated cylinder.

As was described in the prior and sole application of Leo M. KahnSerial No. 620,038, filed October 3, 1945, wherein many of the structural details of the instant washing machine were disclosed, the drying of articles in machines of this. type depends upon the generation of the centrifugal force accomplished by high speed rotation of the cylinder so asto eject the wash water through its perforations. However, the generally unsymmetrical distribution of the articles, particularly in a horizontal axis cylinder, often produces severe vibration which imposes a limit upon the speed of rotation and affects thereby the degree and time of drying. The above application Serial No. 620,038 was directed to the provision of peripherally disposed pockets to which was applied a counterbalance weight in the form of water so as to neutralize the effect of improper weight distribution within the cylinder. In addition, the means chosen to supply the counterbalancing water to the proper pockets involved an empirical process wherein the effects of adding the water arbitrarily were measured in terms of increased or reduced vibration of the rotating cylinder. The instant application, however, has

' as its principal object the effective identification of a particular portion of the cylinder in which the overweight occurs and the automatic application of weight counterbalance material to neutralize such overweight and secure a satisfactory rotating balance.

Another object of this invention is to select and momentarily isolate spaced peripheral portions of the rotating cylinder and simultaneously test such portions for unbalance. Such selection and isolation is produced by means synchronized with the rotation of the cylinder. Allied with this ob- Ject is the provision of means to continue the application of counterbalancing forces to the correct portions of the rotating cylinder notwithstanding continued rotation whereby other portions of the cylinder are presented for unbalance testing. However, whenthe correct portion has already been established, the continued rotation does not have the effect of either momentarily discontinuing such application or shifting it to other and incorrect portions of the cylinder.

Another object of this invention is to provide a series of spaced peripheral pockets on a washing machine cylinder combinedwlth means to apply a counterbalance to more than one of the pockets simultaneously according to the site of unbalance in the cylinder. Thus, where the unbalance can not be corrected by injecting material in only one of the pockets, it may be secured by so treating a plurality of the pockets.

Still another object of this invention is to produce a balancing system for rotating washing machine cylinders which is simple, economical to manufacture and requires a minimum of operating parts.

Other objects of our invention will be apparent from the following description, it being understood that the above general statements of the objects of our invention are intended to describe and not limit it in any manner.

Referring to the drawings:

Fig. 1 is a side view in elevation, partly in section, of a preferred embodiment of the instant invention.

Fig. 2 is an enlarged, fragmentary, cross sectional view of the valved weight injecting end of the machine.

Fig. 3 is a cross sectional view taken along the line 33 of Fig. 2.

Fig. 4 is a schematic circuit diagram of the electrical controls for applying the counterbalance forces.

Fig. 5 is a schematic representation of the cylinder and illustrating a particular portion thereof having an excess of weight which requires neutralization.

Fig. 6 is an electrical diagram illustrating the action of the electronic tubes in response to the condition of unbalance represented by Fig. 5.

Fig. 7 is an electrical diagram illustrating the action of the tubes in accommodating a state of unbalance wherein counterbalance forces must be applied to more than one point of the cylinder.

Fig. 8 is a schematic representation of the cylinder illustrating the site of overweight to be such as to produce the conditions of Fig. '7.

Fig. 9 is a modified embodiment of the electrical circuit disclosed in Fig. 4.

Fig. 10 is a schematic circuit diagram which may be utilized in improving the precision of the counterbalanc applications.

Fig. 11 is a view similar to Fig. 2 and illustrating further details of the weight receiving pockets schematically shown in Fig. 1.

The apparatus comprises an outer shell I 5 supported by base 16 and having the usual valved water inlet l1 and the valved waten outlet or dump l8. Within central openings formed in the end walls of shellli are disposed anti-friction 3 bearings l9 and 20 respectively supporting trunnions 2| and 22 of the washing cylinder 23.

Washing cylinder 23, apart from the peripheral pockets hereinafter disclosed, is of generally conventional form and is adapted to contain articles to be washed and damp-dried through the centrifugal extraction of water. Suitable doors 24 and 25, respectively formed in the shell is and washing cylinder 23 are arranged to register with each other so as to permit the introduction or withdrawal of articles from the washing cylinder 23.

Rotating motion is imparted to cylinder 23 .by the variable speed electric motor 26, the pulley 21 of which drives a belt 23 so as to actuate the pulley 23 connected to the trunnion 22. As is conventional in apparatus of this type, the slower speeds of motor 26 serve to rotate the cylinder 23 at a slow or washing speed so that the articles are tumbled about the cylinder and become washed. The cylinder is provided with the usual ribs, not shown, for agitation or tumbling of the clothes. I

After washing and one or more stages of rinsing, the rotating speed of cylinder 23 is increased, the dump I3 is opened and the centrifugal force resulting from the increased speed ejects the water from the washed clothes whereupon the water flows through the open dump i3 by means of the cylinder perforations 30.

After the clothes have been washed at the slow washing speed and the rotation of the cylinder has been increased for water extracting purposes, any unbalanced distribution of the articles in the cylinder will be manifested by vibration of the cylinder and shell. Such vibration is a source of noise, wear and danger. It is desirable, therefore, to correct the weight distribution so asto eliminate or neutralize the vibration. Accordingly, means are provided to inject compensation weight at selected portions of the cylinder 23 so as to equalize the distribution of weight therein. Such weight compensating means takes the form of water pockets 3|, 32 and 33 equally spaced 120 degrees apart on the peripheral surface of the cylinder 23. It will be appreciated, however, that the number of water pockets may be varied as desired and will be spaced accordingly. Furthermore, the pockets may be formed within the conventional agitating ribs, not shown, such as the hollow hydraulic cylinder pockets shown in the application of Leo M. Kahn, Serial No. 610,035, now Patent #2528594, filed August 10, 1945.

The water pockets shown may be secured to the cylinder 23 by means of rivets, welding or any other suitable means of connection.

Means are provided to inject balancing weight material into the pockets selectively so as to differenti ally affect the balance of the cylinder. It will be apparent that such material injected into any one of the pockets will modify the peripheral weight distribution and apply a centrifugal force at the site of said one pocket. Trunnion 2| is formed with three concentrically arranged channels for applying water from water pipe 35 to selected pockets of the cylinder. Inner channel 38 is formed with a branch 31, and a continuation pipe 33 which connects with pocket 32 so as to introduce water thereto under specific conditions to be hereinafter described. Intermediate channel 39 is formed with a branch 40 and a continuation pipe 4| which connects with pocket 33 so as to similarly supply counterbalance fluid thereto. Outer channel 42 is formed with a branch 43 and a continuation pipe 44 which supplies the counterbalance fiuid to pocket 3|. The

' cylinder.

of the arcuate nature of the pockets as disclosed. I

The floors of the pockets which are comprised of the periphery of the cylinder may be concentric with the longitudinal axis of the cylinder but, in order to decrease the discharge time, the floors 32a may be sloping as shown in Fig. 11 and in the above mentioned prior patent application. It will be evident that when the cylinder stops rotating, centrifugal force will no longer maintain the injected water against the ceiling of the pockets but, on the contrary, it will flow down and through the discharge outlets 34.

counterbalance fluid in the form of water is arranged, through any suitable source of water under pressure, to flow through pipe 35 into one or two of the

valve openings

48, 49 and 50 respectively connected to the inner channel-36, the I intermediate channel 33 and the outer channel- 1 The face 5| of trunnion 2| is formed with 42. three

concentric troughs

52, 33 and 54 connected respectively with the

valve openings

53, 49 and 43. The purpose of the concentric troughs is to permit water to flow from pipe 35, into a valve opening and thereafter into one of the water channels notwithstanding continued rotation of the It will be understood that notwithstanding the radial posltion of the channels in respect to its complementary valve opening, water may nevertheless flow in any selected trough from the valve opening whereupon the water will flow into the channel which is connected to the selected trough. In this manner, the water receiving pockets will fill faster than would be the case were the channels to receive water from the valve openings only during such part of the rotation cycle when the selected channel was in alignment with the open valve.

Means are provided to select the course of site of the compensating fluid by selectively actuating the

valves

56, 51 or 58 or any two of the valves according to the conditions to be corrected.

Valves

56, 51 and 58 may comprise the armatures of solenoids 59, 60 and Si. It will be understood, therefore, that whichever of the solenoids are energized will determine the flow of the comcnsating fluid to the particular portions of the cylinder so as to modify the weight distribution thereof as required. The means for the selective actuation of the solenoids are provided in the electrical circuit hereinaft;r set forth.

The present apparatus applies compensating fluid to selected and spaced pockets during the rotation of the cylinder and in response to a specific condition of unbalance. It is necessary, therefore, that information be supplied not only concerning the presence of a predetermined degree of unbalance, but the portion of the cylinder where such unbalance exists so that corrective measures may be taken. Such corrective measures are, according to the instant invention, automatically put into effect when conditions so require. Means synchronized with tharotation of the cylinder are utilized to provide a reference voltage by which the instantaneous position of particular portions of the cylinder may be identified or momentarily isolated. Thus the site of any unbalance can be located, the presence and degree of which is indicated by a vibration responsive device as hereinafter described. We have devised an electrical circuit which reacts to Joint stimuli one of which is a reference voltage and instantaneously identifies or isolates the successive portions of the rotating cylinder while the other provides an indication of the degree of unbalance. Jointly, they produce a reaction in the circuit which is so timed by ,the reference voltage that the site of the correction is established thereby. Such reaction is arrangedto energize one or more of the solenoids so as to open selected valves and introduce counterbalance fluid into selected peripheral portions of the cylinder during its rotation.

In order to determine the degree of unbalance, a magnetic, vibration pick-up device may be utilized. It is apparent, however, that any equivalent device such as a strain gauge pick-up may be used. It will. be understood that the pick-up not only determines the degree of unbalance but correlates such information with the site of the unbalance depending upon the phase of the electrical signal produced by the pick-up. The output of the pick-up, as is well understood, is of substantially sine wave form produced pursuant to the vibrations of the cylinder in a condition of unbalance. A magnet 65, connected by bracket 66 to an external support is arranged to co-act with pick-up coil 68 so as to cause the induction of alternating voltages therein. An arm 69 having a contact is spring pressed against the shaft 61 and connected so as to shift the coil 68 and cut the magnetic field in accordance with the vibration of the shaft. It will be recognized by those skilled in the art that the representation of the pick-up device in Fig. l is schematic and that any conventional apparatus such as a piezo-electric crystal pick-up may be employed.

The sine wave voltages as applied to the electrical lead wires II and 12 are fed to an amplifier .13 for the usual amplification purposes. Since the sine wave voltages may be of a low frequency, amplifier 13 may be of the direct coupled type or any amplifier adapted to accommodate currents of low frequency. These sine wave voltages are thereafter fed to a selector H, which, as hereinafter described, is an electrical network having electronic tubes for selecting the valves to be actuated according to the information supplied to it in the form of electrical signals or intelligence. It is desirable to avoid actuation of the system by harmonics of the sine wave voltages if any are present. This may be accomplished, as will be recognized by those skilled in the art, by providing suitable filters in the input of amplifier 13. Since the unbalance correction need not be instituted until high speed rotation of the cylinder, the range of frequencies involved will not be very great and the filtering thereof may be easily effected.

Means are also provided to isolate or identify spaced peripheral portions of the rotating cylinder so as to correlate the information supplied thereby with that supplied by the vibration pickup.

Referring to Fig. 4, a distributor disc 15 is mounted on the shaft 61 so as to rotate together with the cylinder 23. The distributor is arranged to successively apply electrical voltages to the brushes 16, I1 and 18. In the embodiment of Fig. 4, the power supply 18 may comprise a di rect current source in the order of 150 volts to which is connected the wiper arm 88. Arm 80 makes wiping contact with ring 8| which is of electrically conducting material. Integral with ring 8| is a voltage transmitting contact segment 82 which preferably, but not necessarily, occupies approximately degrees of the ring 8| for purposes to be hereinafter described. Asthe distributor disc 15 rotates together with the cylinder 23, the volts potential from power supply 18 is successively applied to each of the bligfihes as the segment 82 makes contact therew Energizing means for each of the solenoid coils 58, 66 and 6| are provided in the form of

electronic tubes

62, 63 and 64 of which the respective solenoid coils constitute the plate loads thereof.

Tubes

62, 63 and 64 are preferably, but not necessarily, of the Thyratron type which are capable of handling large amounts of power. It will be apparent that voltages for the

plates

65, 66 and 67 of each tube are applied respectively and successively by means of the brushes TI, 18 and I6. Suitable bias for the tubes may be employed and the grids thereof may be grounded through the usual high grid leak resistance, if desired. Two or more Thyratrons, or any number of gas-filled tubes, may be used in parallel for each solenoid, if necessary.

As the distributor disc 15 rotates, each tube will successively have plate voltage applied thereto at the same time that the amplified sine wave voltage from the vibration pick-up is applied to the grids thereof. This will set up a condition where the current flow in the plate circuit will be governed by the phase relationship of the grid and plate voltages. In one sense, it may be considered that the voltages applied to each plate are alternating. Since the phase of the grid voltage will depend upon the site of unbalance, variations ofsuch site will vary the relative phase of the two voltages on each tube, that is, the relative time at which they reach their peak values. If the phase of the grid voltage lags the plate voltage by degrees, the plate current will be entirely out off. When both the grid and plate of any tube is positive, plate current'will flow, the positive value of grid current depending upon the firing voltage in the tube as determined by its constants and the bias thereon. If in a modified circuit valve actuation is dependent upon negative grid voltage, the same principles will obtain as where the de-energization of a tube releases a relay or the like which closes the current to valve actuating means.

Referring to Fig. 5, the X marks a point in the loaded cylinder wherein an overweight exists. In order to establish balance, it is necessary to apply the material to pocket 32. Assuming, therefore, that the distributor disc 15 is so keyed to shaft 6'| so that positive voltages are successively applied to the circuits controlling the ap plication of counterbalance fluid to pockets 3|, 32 and 33 in that order, each such circuit will be successively primed so as to conduct whenthe grid voltage reaches its positive firing value. Referring to Fig. 6, the square wave 85 may represent the plate voltage on tube 64 the solenoid winding 6| of which controls the armature valve 58 which in turn controls the application of counterbalance fluid to the pocket 8|. After the distributor has moved approximately 110 degrees, the plate voltage to tube 64 will be cut off and approximately 20 degrees thereafter will be applied as square wave 86 to the plate 86 of tube 83 which controls the application of counterbalance fluid to pocket 92. Similarly. square wave I1 is shortly thereafter applied to the plate 65 of tube 62, the voltage 66 having previously been removed from the plate 66. The cycle thereupon repeats itself as illustrated in Fig. 6. At the same time that the plate voltages are successively applied to the three tubes, the sine wave pick-up voltage generated by the vibration of the cylinder is applied to the grids ll, 69 and 90 of the respective tubes. The pick-up apparatus is so disposed on the shaft 61 in relation to the distributor connection thereto, that the grid voltage 9| generated pursuant to the unbalance at point X in Fig. 5, produces a trough at approximately the same time that voltage 66 is applied to plate 61. The crest of the grid voltage 9| appears during the period when voltage 66 is applied to tube 66. When voltage 61 is applied to the plate, voltage II is once more descending into its trough. The ilring voltage 92 is that potential at which the grid must be in order to fire the tube at its conditions of operation. The values are well known .to those skilled in the art and are determined as hereinabove set forth. Assuming that the firing grid voltage in a particular design of circuit is 10 volts of positive current, the tube 63 will fire when the grid voltage reaches the dotted line 92 representing the firing voltage. Considerable plate current will flow through the tube 69 so as to actuate the valve 61 and permit fluid from pipe II to be applied to the pocket 31. The fiuid will therefore be correctly applied so that the cylinder approaches a condition of balance. It may be desirable if large degrees of unbalance are to be expected. to limit the amplitude of the grid voltage so that the width of its positive portion is not appreciably greater than that of the square wave plate voltage. As will be apparent to those skilled in the art, this may be done by a delayed automatic volume control (AVC) circuit in the amplifier, or by mechanical limiting means against the shaft 61.

The broken lines defining the grid voltage peak in Fig. 6 illustrate the simultaneous application of the vibration signal and plate voltage to tube 63. It will be understood that as the counterbalance fluid is unblocked from pocket 32 by the actuation of valve 51, the amplitude of the grid voltage will decrease as the vibration decreases pursuant to the correction of unbalance.

when the amplitude is such as to descend below the firing voltage 92, the tube 69 will be extinguished notwithstanding the coincidence of the plate and grid voltages. It is a recognized characteristic of gas-filled tubes of the Thyratron type that mere removal of grid firing voltage does not per se produce tube extinction. However, our method of removing the plate voltage by the distributor means described insures proper extinction of the tubes since it is well known that the absence of plate potential will produce this effect. Thus, the present invention an adjacent portion. For this reason, the segso as to decrease the possibility of consequent erratic operation which might otherwise ensue.

Referring to Fig. 6, if the grid voltage 9| were shifted slightly either to the left or right so as to overlap square wave 96 in regard to time or phase, it would not reach either ofthe adjacent plate voltages so as not to,be coincident therewith. Accordingly, a margin isprovided wherein corrective action is not tak so that the angular sensitivity is decreased thereby. when, however, the pocket 32 has been supplied with sumcient counterbalance fluid to represent a force of the necessary magnitude. the total vibration will be so little that the firing voltage line 92 will not be reached and compensation will cease.

Since the tubes will successively extinguish as the distributor rotates, under ordinary conditions the valves would be de-actuated between firing periods so that counterbalance iiuid would only flow when the tube was firing and the water would therefore flow in spurts. In order to eliminate such periodic action, means are taken to continue the energization of the solenoids for a period after the tube associated therewith has been extinguished and until the tube re-flres when the plate voltage is re-applied thereto.

Accordingly, hold-over circuits in the form of

condensers

96, 96 and 91 are connected across the respective solenoid windings. The distributor action will charge'each condenser each time that plate voltage is applied to the tube associated therewith. when the source of voltage is removed, the condenser will maintain energization of the solenoid by discharging therethrough. The value of

condensers

96, 96 and 91 will be chosen so as to produce a time constant network which is correlated with the speed of cylinder rotation. It will be apparent that if the cylinder rotates three times a second, for example, the time constant may be in the order of one-third of a second and the hold-over circuit elements will be selected according to well known standards. By this means, when the correct pocket or pockets have been selected for the introduction ofcounterbalance material, the application of such material will be continued to such pocket until balance is achieved notwithstanding the periodic extinction of the tube which controls its valve.

In Fig. 8, the x marks a point in the loaded cylinder wherein an overweight exists. In order to establish balance in such a condition, it is necessary to apply the counterbalance material simultaneously to pockets 3| and 92. Referring to Fig. '7, it will be seen that the phase of the plate voltages remains fixed, being in the same phase as illustrated in Fig. 6. This, of course, is because the keying of the distributor disc II to shaft 61 remains undisturbed and at all times thereafter determines the phase of the plate voltages. The grid voltage 99 has, however, shifted approximately 45 degrees as determined by the respective X points in Figs. 5 and 8, so that the positive peak of the grid voltage is coincident with both plate voltages 66 and 61. Accordingly, both

tubes

62 and 64 will fire whereupon the consequent actuation of

valves

66 and 66 will effect the introduction of counterbalance material to the pockets 3| and 32 simultaneously. It will be understood, therefore, that more than one, but less than all of course, of the pockets may be filled simultaneously in response to a condition of unbalance.

Whereas a cylinder having three pockets has been shown, it willbe obvious that many. more such pockets may be provided if finer degrees of tacting segment of an extent commensurate with thedivision of the number. of pockets into 360 1 degrees as will be evident. Furthermore, other methods of applying the plate voltages may be employed, such as that of a pilot generator which produces. plate voltages from the rotation of the cylinder itself and eliminates the necessity of a power supply. a

In Fig. 9 is illustrated a modified embodiment of the selector circuit wherein ordinary vacuum tubes may be employed. In this case, the plate voltages are constantly applied to the tubes I00, III and I02. However, the vibration pick-up grid voltages are distributed to the grids I 03, I04 and I05 through the distributor disc I08. The wiper arm I01 is connected to one terminal of the amplified vibration pick-up voltage, the other terminal of which may be suitably grounded. The contact segment I08 receives the gridvoltages and applies them through the brushes I00, H and III to the grids as aforesaid. As before, the phase of the grid voltage will depend upon the site of unbalance. As this voltage is distributed to the grids, it is broken up into three components one or more of which,

but less than all, will include the positive -portion of the grid voltage. The bias of each tube is arranged as by cathode bias resistors I I 0,- I I and I I0 so that the tube will conduct at a predetermined grid potential. Conventional means are provided to maintain the tubes normally at or near their cut off state so that thesolenoids II'I, H8 and H9 are not energized. However, whichever 0f the tubes receives the positive portion of the pick-up signal of proper amplitude 'will conduct so as to open the correct valves and approach or effect balance as hereinabove described. The usual grid leak resistors I20, I2I and I22 are provided and the holdover condensers I23, I 24 and I 25 form a time constant network therewith for the purposes above described. Sincetubes I00, IN and I02 are riot of the gasfilled type, they may be cut oil! without removing the plate voltage but ordinarily such tubes, unless made very large, can not handle adequate power. Accordingly, it may be desirable to provide a plurality of such tubes in parallel, or the solenoids III et seq may take the form of relays for closing another power circuit which will suit-. ably actuate the necessary valves.

In Fig. is illustrated an additional safe-, guard for eliminating a possibility of erratic op-" eration or hunting. in the apparatus. For example, should a pocket overfill due to lag in operation of any solenoid, the site of unbalance would be shifted to a diametrically opposite point and further correction would be made by applying the fluid to diiferent pockets. It is desirable,

however, to provide a margin of tolerance where-* by a slight over-correction will not shift the application of counterbalance fluid. The firing voltage level 92 is ordinarily set by the bias on the grids B8, 89 and 93 of the valve control tubes. Such bias may be app ied to the grids t rough a spring arm I30 having a contact point I3I which normally makes electrical contact with terminali32 which is connected to a negative point of voltage I33. However, when any one of the valves 50. 51 or 58 is actuated, it li ts arm I30 so thatcontact I3I removes the bias of point I33 and contact I34 is caused to meet arm I35 which is connectedto a less negative voltage point I30. Correction will thereupon continue until the pick-up'voltage 'is so low that it does not reach the firing'voltage line represented by the lower firing voltage point I36. After correction has been established and the actuated valve has returned to normal position, the arm I30 will likewise be restored to normal position and the higher bias will then be applied so that a slight overflow will not produce .sufiicient amplitude of firing voltage to strike at the new point of operation. This feature will be further useful in avoiding erratic operation as the water is extracted from the clothes during the extracting process so as to change the weight distribution. However, since the great bulk of the water is extracted during the'beginning of the extracting operation "and since proper balancing has been initially approached, subsequent unbalance will be of considerable less importance.

We have shown a preferred embodiment of our invention, but it is obvious that numerous changes and omissions may be made therefrom without departing from its spirit. For example, while we have illustrated the achievement of balance through theaddition oi counterbalance fiuid to selected sites on the periphery of the cylinder, it will be apparent that the invention can be adapted toward the release of fluid from a normally filled pocket. In other words, the vibration responsive device would be so situated with respect to the distributor contact segment that a valve of a receiving element at the site of unbalance would be actuated so as to. release water from the pocket at that site. Obviously a source of water supply from the pipe will not be required in such an embodiment and the release of water will serve tomodify the peripheral weight distribution of the cylinder. Furthermore, since the invention is adapted toward the release of fluid from anormally filled pocket, it is possible to provide balancing apparatus in a two pocket cylinder. In such a structure it would be unnecessary to provide the water-tight bearing means illustrated in Figs. 2 and 3 hereof since the counterbalance fluid may be removed or applied centrally of the trunnions. A structure illustrating a cylinder with two cally opposed "water receiving pockets and providing for the application of fluid thereto through the cylinder trunnions is illustrated in the above mentioned sole patent application of Leo M. Kahn Serial No. 620,038. However, in an embodiment con tructed according to the instant invention, the two pockets would be spaced degrees apart on the cyl nder and the balance may be achieved by providing means for both adding water and releasing water selectively from either pocket. It will be recognized that the provision for either removing or releasing water from a pocket wherein two pockets spaced at 90 degrees are provided, is equivalent to providing four pockets spaced at 90 degrees wherein counterbalance fluid can be either removed or applied, but not both. As regards the use of a pi ot generator mentioned above, it will be recognized by those skilled in the art that the generator would produce a reference sine wave voltage instead of the square waves produced by the distributor. reference sine wave would be correlated witlf't time. By applying the phases of the pilot gen.-

diametri- Ho ever, the" phase of the asaaaes therewith may selectively close electrical cir-.

cuits tor actuating the proper valves.

As will be apparent to those skilled in the art, the amplifier II will be capable of gain adjustment so that the unbalance indications can be amplified as desired. Similarly, the bias on the tubes may be adjusted depending upon the level at which correction is desired.

We claim:

l. Balancing apparatus for a rotating cylinder for housing wet articles from which liquid is to be centriiugally extracted, comprising a series of counterweight receiving elements loca at spaced peripheral portions of said cylinder, means to feed liquid counterweight material to said receiving elements, inlet controls for blocking said material from said receiving elements, control operating means for selectively unblocking at least one or said receiving elements so as to introduce said counterweight material thereto, a vibration responsive device for producing a series of electrical response pursuant to vibrations of said rotating cylinder, means synchronized with its. rotation for successively establishing the instantaneous angular position oi said spaced portions of said cylinder, and means jointly controlled by said series of electrical responses and by said synchronized means for actuating said control operating means.

2. Balancing apparatus for a rotating cylinder for housing wet articles from which liquid is to be centriiugally extracted, comprising a series oi counterweight receiving elements located at spaced peripheral portions of said cylinder, means to feed counterweight material to said receiving elements, inlet controls for blocking said material from said receiving elements, inlet control operating means for selectively unblocking at least one oi! said receiving elements so as to introduce said counterweight material thereto, a vibration responsive device for producing an electrical voltage of substantially sine wave form pursuant to vibrations of said rotating cylinder, means synchronized with its rotation for successively establishing the instantaneous angular position of said spaced portions of said cylinder, and means jointly controlled by the amplitude oi. a predetermined portion of said sine wave voltage and by said synchronized means for actuating said unblocking means.

3. Balancing apparatus for a rotating cylinder comprising a plurality of weight receiving elements adapted to receive weight counterbalance material from a source thereof, control means for selectively applying said material to control said receiving elements, said weight receiving elements being respectively disposed in spaced portions of said cylinder so as to difierentially ailect the balance thereof when said counterbalance material is selectively applied thereto, a vibration responsive device adapted to produce a first electrical output pursuant to the vibration of the rotating cylinder, said control means comprising normally inactive electronic tubes associated with each of said receiving elements, plate and grid electrodes in said trically establish the angular positions of said weight receiving elements of said rotating Y inder so as to produce a series oi second electrical outputs each correlated with a Sp i weight receiving element or said cylinder and means to apply both a predetermined controlling portion of said first electrical output and one of said series of second electrical outputs to at least one or said electronic tubes in said control means so as to actuate said one electronic tube when a predetermined degree of vibration exists in said rotating cylinder whereby counterbalance material is applied to the receiving element associated with said one electronic tube, ot r portions oi. said first electrical output be g applied to other tubes so as to continue said other tubes in their normally inactive state.

4. Balancing apparatus according to claim 8 including valves controlled by said control means for introducing counterbalance material to said receiving elements, and solenoids in the plate circuits or said electronic tubes, said solenoids.

being operative to actuate said valves whereby said material may fiow into said receiving elements when the electronic tube associated therewith is actuated so as to energize the solenoid in its plate circuit.

5. Balancing apparatus according to claim 3 including valves controlled by said control means for introducing said counterbalance material to said receiving elements, solenoids in the plate circuits of said electronic tubes, said solenoids being operative to actuate said valves whereby said material may fiow into said receiving elements when the electronic tube associated therewith is actuated so as to energize the solenoid in its plate circuit and a hold-over device in the plate circuit oi. each electronic tube so as to .maintain energization or its solenoid alter the electronic tube associated therewith is de-actuated.

6. Means for balancing vibration in a rotating cylinder comprising a plurality of weight receiving elements adapted to selectively receive counterbalance weight material, from a source thereof, control means for selectively applying said material to said receiving elements, a vibration responsive device adapted to produce an electrical output pursuant to vibration oi the rotating cylinder, said plurality 01' weight receiving elements being respectively disposed in spaced peripheral portions oi said cylinder so as to difierentially afiect the balance thereof when counterbalance material is selectively applied there! to. valves included in said control means for controlling the application 01' said material to said receiving elements, an electronic tube circuit for each of said valves, each said electronic tube circuit being associated with one of said receiving elements, each tube in said circuits having at least plate, grid, and cathode electrodes, a source or plate potential, distributor means synchronized with the rotation of said cylinder for successively applying said potential to the plates of said tubes, means for simultaneously applying the output 01' said vibration responsive device to the grids oi said tubes, said tubes being responsive to a predetermined coincidence oi voltage conditions on their respective plates and grids for actuating said valves so as to apply said material. selectively to said receiving elements.

7. Balancing apparatus according to claim 8 wherein said vibration responsiv device electrielectronic tubes, means to successively eleccal output is a sine wave, and said coincidence or voltage conditions comprises .the simultaneout application or a positive portion or said sine wave of predetermined amplitude on any grid oi said tubes and application oi plate potential to said tube whereby the selected actuation 01 valves in said control means depends upon the phase relationship of the grid and plate voltages.

6. Balancing apparatus according to claim 6 wherein said vibration responsive device electrical output is a sine wave, and said coincidence of voltage conditions comprises the application oi a positive portion or said sine wave and of a predetermined amplitude thereof on the grid of 'any or said tubes, and th simultaneous application of plate voltage to the plate of said tube, whereby the selected actuation of valves in said control means depends'upon the phase relationship of the grid and plate voltages, the application of voltages to the plates being synchronized with the rotation of said cylinder so as to have a relatively constant phase, said grid voltage having a varying phase depending upon the site of unbalance, the frequency of the grid voltage being lower than that of the plate voltage in proportion to the number of receiving elements in the apparatus, saidnumber being at least three so that said conditions of coincidence may occur in more than one tube whereby more than one receiving element may be supplied with said counterbalance weight materialat any one time.

9. Balancing apparatus according to claim 6 wherein said tubes comprisegas-filled electronic tubes adapted to fire under predetermined conditions of grid voltage and wherein said vibration responsive device electrical output is a. sine wave, and said coincidence of voltage conditions comprises the application oi' a positive portion 01' said sine wave and of a predetermined amplitude thereof on the grid of any of said tubes and the simultaneous application of plate voltage to the plate of said tube, whereby the selected actuation of valves in said control means depends upon the Phase relationship of the grid and plate voltages, the application of voltages to the plates being synchronized .with the rotation of said cylinder so as to hav a relatively constant phase, said' grid voltage having a varying phase depending upon the site of unbalance, said phase variation of grid voltage with respect to plate voltage being such that said conditions of coincidence may occur in more than one tube whereby more than one gas-filled tube may fire simultaneously and more than one receiving element may be supplied with said counterbalance weight material at one time.

10. Balancing apparatus according to claim 6 wherein said vibration responsive device electrical output is a sine wave, and said coincidence of voltage conditions comprises the application of a positive portion of said sine wave and of a predetermined amplitude thereof on the grid of anv of said tubes and the simultaneous application of plate voltage to the plate of said tube, whereby the selected actuation of valves in said control stores said coincidence of voltage conditions to said tube before said valve is de-actuated.

11. Balancing apparatus according to claim 6 including means to separate the successiv applications of plate potential to the plates of said tubes whereby said voltage condition on a grid may overlap the plate voltage in a tube in extent of time without being brought into time coincidence with the plate voltage or an adjacent tube.

-12. Balancing apparatus according to claim 6 including means to separate the successive applications of plate potential to the plates of said tubes whereby said voltage condition on a grid may overlap the plate voltage in a tube in extent of time without being brought into time coincidence with the plate voltage of an adiacent tube. said means to separate the successive applications comprising a series of radial segments on said distributor means, each of said segments being connected to the respective plates of said tube and having plate potential successively applied thereto so as to successively transfer such potential to said plates, said segments occupying an arcuate area 01' less than a predetermined fraction of 360 degrees, said fraction resulting from a division of 360 degrees of cylinder periphery by the number of receiving elements thereon.

13. Means for balancing vibration in a rotating cylinder comprising a plurality of weight receiving elements adapted to selectively receive counterbalance weight material, from a source thereof, control means for selectively applying said material to said receiving elements, a vibration responsive device adapted to produce an electrical output of sine wave form pursuant to vibration ofthe rotating cylinder, said plurality of weight receiving elements being respectively disposed in spaced peripheral portions of said cylinder so as to .difierentially affect the balance thereof when counterbalance material is selectively applied thereto, valves included in said control means for controlling the application of said material to said receiving elements, an electronic tube circuit for each of said valves, each said electronic tube circuit being associated with one of "said receiving elements, each tube in said circults having at least plate, grid and cathode electrodes, a potential supply for the plates of said tubes, distributor means synchronized with the rotation of said cylinder for successively applying portions oi the sine wave output of said vibration responsive device to the grids of the tubes whereby each grid receives an equal portion of said sine wave, the positive portion of said sine wave being limited to lessthan all of said grids. said positive portion being operative to actuate the tube, the grid of which it is applied to whereby the valve associated with said tube is actuated so as to apply said material selectively to said receiving elements.

14. Balancing apparatus for a rotating cyl nder comprising a vibration responsive device adapted to produce a first electrical output pursuant to vibrations of the rotating cylinder,

means to electrically establish the angular position of spaced portions of said cylinder during its rotation so as to produce a second electrical output thereby, means iointly actuated by a predetermined level of said first electrical output and by said second electrical output for applying a counterbalance force to said cylinder as determined by both a predetermined extent of unbalance indicated by said first electrical output and the site of said unbalance as determined by said second electrical output, and means to increase the actuating level of said jointly actuated means after a counterbalance force has been applied whereby said vibrations must rise to a substantially higher amplitude after such application in order to resume the application of counterbalance forces thereby.

15. Balancing apparatus for a rotating cylinder for housing wet articles from which liquid is to be centrifugally extracted, said cylinder comprising a plurality of weight receiving elements arranged to contain quantities of counterbalance material, control circuit means for automatically regulating the quantity of such material in the respective elements, said receiving elements being respectively disposed in angularly spaced peripheral portions of said cylinder so as to differentially affect the balance thereof depending upon the quantities of counterbalance material contained in the respective receiving lements, an electrically controlled vibration responsive device adapted to produce an electrical signal pursuant to the site of overweight of said articles in the rotating cylinder, said control circuit means being automatically actuated by said electrical signals so as to vary the counterbalance material contents of at least one of said receiving elements during a state of unbalance of the rotating cylinder, said control circuit means being continuously operable during rotation of said cylinder and during gradual liquid extraction of said articles so as to continue the automatic varying of said contents as said site of overweight may shift.

16. Balancing apparatus for a rotating cylinder for housing wet articles from which liquid is to be centrifugally extracted, comprising a vibration responsive device arranged to produce an indication of unbalance pursuant to vibrations of the rotating cylinder, inlet control means to supply counterbalance material from a source thereof to spaced peripheral portions of said rotating cylinder, rotating means for successively establishing the angular position of said spaced portions of the rotating cylinder, inlet control actuating means jointly controlled by said vibration responsive device and said rotating means for selectively actuating said inlet control means so as to supply said material to one or more of said spaced portions, and a hold-over member to continue supplying said material to said one or more of said spaced portions during continued rotation of said cylinder.

17. Balancing apparatus for a rotating cylinder for housing wet articles from which fluid is to be centrifugally extracted, comprising a plurality of weight receiving elements arranged to receive weight counterbalance material from a source thereof, control means for selectively applying said material to said receiving elements, said weight receiving elements being respectively disposed in spaced peripheral portions of said cylinder so as to differentially affect the balance thereof when said counter-balance material is selectively applied thereto, a vibration responsive device arranged to produce a first electrical output pursuant to the vibration of the rotatin cylinder, means to successively electrically estabelements of said rotating cylinder so as'to produce a cyclical series of second electrical outputs corresponding to such angular position, said control means being connected to receive said first and second electrical outputs and being actuated jointly by a time coincidence of said first elec-. trical output and less than all of the second electrical outputs of any one cycle so as to app y' said material to at least one of said receiv 8 elements selected according to the amplitude of vibration occurring during the establishment of the angular position of one or more receiving elements.

l8. Balancing apparatus according to claim 17, including means to continue said application of said material to said selected receiving elements during continued rotation of said cylinder and subsequent establishment of the angular position of the remaining receiving elements by said series of second electrical outputs.

19. Balancing apparatus according to claim 17 including an electrical hold-over network of a value correlated to the speed of rotation of said cylinder whereby said Joint actuation of said control means is held over between periods when the electrical output establishing the angular position of selected receiving elements is-applied, coincidental with said first electrical output, to said control means.

20. Balancing apparatus for a rotatable hollow cylinder of a machine for treating discrete articles comprising a plurallty'of weight receiving elements arranged to house varying amounts of weight counterbalance material, said weight relish the angular position of the weight receiving ceiving elements being angularly disposed around said cylinder so as to differentially affect the balance thereof pursuant to the varying amounts ofsaid material housed therein. inlet control means including an electrical circuit for selectively varying the amounts of said material housed in said receiving elements, a vibration responsive device arranged to provide an electrical voltage pursuant to the passage of an overweighted portion of the rotating cylinder, and referencemeans continuously operative during the rotation of the cylinder for registering the momentary angular disposition of each weight receiving element, said inlet control means being controlled jointly by said vibration responsive device electrical voltage and the action of said reference means so as to vary the amounts of said material in one or more of said weight receiving elements depending upon the site of said overweighted portion.

21. Balancing apparatus for a rotatable hollow cylinder comprising a plurality of weight receiving elements arranged to receive counterbalance liquid from a source thereof, said weight receiving elements being respectively disposed adjacent spaced-periphe'ral portions of said cylinder so as to diflerentially affect the balance thereof when said liquid is selectively applied thereto, inlet control means for selectively applying such liquid to such receiving elements, a vibration responsive device arranged to provide an electrical voltage at a time coinciding with the passage of an overweighted portion of the rotating cylinder, reference means operative by the rotation of the cylinder for registering the momentary angular disposition of each weight receiving element, said control means being activated Jointly by said vibration responsive device and said reference means so as to apply said liquid to one or more of said weight receiving elements which are in a portion of said cylinder substantially opposed to said overweighted portion, and a hold-over element acting on said control means whereby said control means acts to continue the application of said liquid after the joint control thereof terminates.

22. Balancing apparatus for a rotatable hollow cylinder comprising a plurality of weight receiving elements arranged to receive counterbalance liquid from a source thereof, said weight receiving elements being respectively disposed adlacent spaced peripheral portions of said cylinder so as to differentially affect the balance thereof when said liquid is selectivelyapplied thereto, an inlet and inlet control means for each weight receiving element including an electrical circuit for selectively applying such liquid to said receiving elements, a vibration responsive device arranged to produce an electrical voltage having one voltage peak during each revolution of the rotating unbalanced cylinder and occurring at a time coinciding with the passage of an overweighted portion of the rotating cylinder, reference means for establishing the identity of any one of said receiving elements as the receiving element passes a predetermined line during its rotating travel, said reference means being operative to produce a series of voltage peaks each corresponding to one of said receiving elements, said reference means voltage peaks successively following each other in time and having a higher frequency than said vibration voltage whereby the time duration of said vibration voltage peak may cause it to overlap more than one reference means voltage peak depending upon their phase relationship, said inlet control means being operated by a time coincidence of a vibration voltage peak and a reference means voltage peak so as to apply said liquid to the receiving element whose reference means voltage peak coincides with the vibration voltage peak in any one rotation of the cylinder, whereby the liquid may be simultaneously fed to more than one receiving element.

23. Apparatus according to claim 22, wherein said vibration voltage is of substantially sine wave form and of the same frequency as that of the rotating cylinder so that its peak occupies almost one half of the rotating cycle, said reference means voltage peaks being at least three in number and being equally spaced through said rotating cycle.

24. Balancing apparatus for a rotatable hollow cylinder comprising a plurality of weight receiving elements arranged to receive counterbalance liquid from a source thereof, said weight receiving elements being respectively disposed ad- Jacent spaced peripheral portions of said cylinder so as to differentially affect the balance thereof when said liquid is selectively applied thereto, an inlet and inlet control means for each weight receiving element including an electrical circuit for selectively applying such liquid to said receiving elements, a vibration responsive device arranged to provide an electrical voltage having one voltage peak during each revolution of the rotating unbalanced cylinder and occurring at a time coinciding with the passage of an overweighted portion of the rotating cylinder, reference means for establishing the identity of any one of said receiving elements as the receiving element passes a predetermined line during its rotatin travel, said reference means being operative to produce a series of voltage peaks each corresponding to one of said receiving elements, said reference means voltage peaks successively following each other in time and having a higher frequency than said vibration voltage whereby the time duration of said vibration voltage peak may cause it to overlap more than one reference means voltage peak depending upon their phase relationship, said inlet control means being operated by a time coincidence of a vibration voltage peak and a reference means voltage peak so as to apply said liquid to the receiving element whose reference means voltage peak coincides with the vibration voltage peak in any one rotation of the cylinder, whereby the liquid may be simultaneously fed to more than one receiving element, and a holdover circuit in the electrical circuit of each valve control means, said hold-over circuit being a time constant network having a time delay approximating the time of one rotation of the cylinder.

LEO M. KAHN. EDWIN ELLNER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,554,014 Mac Farland sept. 15, 1925 1,604,748 Grauer Oct. 26, 1926 2,235,393 Baker Mar. 18, 1941 2,322,561 Bevins et a1. June 22, 1943 2,331,733 Senger Oct. 12, 1943 2,346,975 Laboulais Apr. 18, 1944 FOREIGN PATENTS Number Country Date 399,845 Great Britain Oct. 13, 1933