US2648964A - Washing machine - Google Patents

Description

Aug. 18, 1953 G, C, GRAHAM. 2,648,964"

' WASHING MACHINE original Filed Nov. so, 1939 s sheets-snaai 1 G. C.,.GRAHAM WASHING MACHINE Aug. 1s, 1953 .3 Sheets-Sheet 2 Original Filed NOV. 30, 1959 INVEN TOR. Bgm/mf C @fsw/A M W Aug. 18, 1953 G. c. GRAHAM 2,648,964

WASHING MACHINE original Filed Nov. so, 1959 ssheets-sn'gat :s

[N V EN TOR.

@C0/mf 6 6 f/AM ATTO/fwn Patented Aug. 18, 1953 WASHING MACHINE lGeorge C. Graham, Ridgewood, N. J., assignor, by mesne assignments, to Graham & Barker, Ridgewood, N. J., a limited partnership Original application November 30, 1939, VSerial Divided and this application March 2, 1946, Serial No. 651,497

2 Claims. l

My invention relates to washing ymachines Vor devices, exemplied herein as applied for household laundry purposes, and more particularly to improvements in such machines.

This application is a division of my copending application for Washing Machines, Serial No. 306,791, Afiled November 30, 1939, now Patent No. 2,401,660, issued September 17, 1946.

An object of the invention is to provide novel circulation of water, and novel movement of clothes, in a Washing machine, whereby to elTect better interchange of position of the water and clothes Ato ensure eiective cleaning.

Other objects of the invention are the provision of novel agitator or bale means, particular water connections, and other elements.

Another object of the invention isto provide a washing machine of the aboverindicated character that is simple and durable in construction, ecQIlOmical to manufacture and effective in its operation.

Another object ofthe invention is to provide a ,novel lresilient or shock-absorbing means for a power unit of a washing machine, exemplified as l.of the oscillating type.

With 'Such objects in View, as Well as `other Yadvantages which Amay be incident to a utilization of the improvements, individually or in combination, the invention comprises the elements and combinations thereof herein set forth and claimed, with the understanding that the several necessary elements constituting the same may be varied in proportion, arrangement and texture, without departing from the spirit and scope of the invention as intended, and as 4set forth in the drawings, specification and claims.

In order to render the invention more ,clearly understood, means are shown in the accompanying drawings for carrying the invention into practical effect, without limiting the improvements to the particular elements Ishown and described, which for the purpose of explanation, are made the subject of illustration.

In the drawings:

Figure 1 is a front side View, partially in elevation and partially in substantially central vertical-plane section, of a washing machine of a particular type constructed in accordance with the invention;

Fig. 2 is a view showing a fragmentary detail .of an upper agitator or baffle element, as viewed in the direction of an larrow 2 of Fig. 1;

Fig. 3 is a sectional view, taken along the line 3-3 of Fig. 2;

Fig. e is a sectional view, taken substantially along the line 4-4 of Fig. 1;

Fig. 5 is an enlarged top plan view of an agitator and a lower portion of a tub; and

Fig. 6 is a vsectional View of the structure-of Fig. 5.

Referring particularly to Fig. 1, the example of the machine therein illustrated comprises a lower base 26, an upper stationary housing 21 on the base 26, an oscillatory tub 28 disposed generally in the housing 21, top or lid construction 3l extending above the housing, an agitator 83 having baille elements or means 32 at the bottom of Athe tub, and bales 34 near'the top of the tub, for agitating `the clothes and water in the tub during washing, ushing, andrinsing actions, a diaphragm 33 in the tub for effecting ,flushing and vdrying actions by expansion ofthe diaphragm, a va1ve36 under the tub for admitting uid behind the diaphragm and -in part controlling operation of the diaphragm 33 a power, .or tub oscillating, unit assembly 4l supported by the `base 26 under the housing .21, and shock absorbing suspension means 42 for the power unit 4I associated therewith. An automatic control mechanism (not shown) Valso is mounted on one side of the .housing 21.

The base structure 26, which may be any one of several different types for supporting the other parts and causing the top of the machine to have `a certain Vconvenient levelsuitable to the average user, has legs 5|, at least two of which. as vseen in Fig. 11, are suitable in location and construction for cooperation with the shock absorbing suspension means 42, as will later be described. The legs 15| are, in this instance, of pressed metal having channel section, joined at the lower ends, as by tie rods 53, and suitably supportinggat .the tops, a metal or other disc or plate 56preferably by means (not shown) for detachably mounting the legs in position. Castors 54 of the swivel type on Ythe legs 5| or other means, may be provided for the easy movement of the machine from one position to another on a floor, in a usual manner.

The plate 56, in this instance, is surmounted by a shell or ring 51 of thin pressed sheet metal having a horizontalperipheral top ilange 58 for attachment to the housing 21, and a peripheral bottom flange 6I telescoping and 'suitably held to the plate 5.6.

The housing 21 encloses the tub 28, and other parts, and receives wash and rinse Water ejected from the to-p of the tub, as will later appear. A pipe B2, extending from the bottomy of the housing through the plate 56, is provided for draining the housing 21. The housing comprises `a thin sheet metal lower cup like portion 63, having an upper vertical peripheral flange 68 to i which is secured an upper thin sheet metal cylindrical member 1|. At its upper end, the cylinder 1| is provided with an annular thin sheet metal shell or cap 12 having an offset perimeter 1.3 secured to the top periphery of the cylinder 1|. The remainder of the cap 12 is of substantially half round section, forming a relatively large upwardly convex bead or toroid, having a relatively small, radially inwardly extending flange 11 about the upper part of the tub 28 and in closely spaced relation thereto. A bushing 18 is provided in an opening inthe shell 12, for a purpose to be hereinafter set forth.

The tub 28 is of the oscillating type for operation about a vertical axis, relative to which its sheet metal body 19 is of somewhat elongated globe shape having a clothes receiving opening at its top, and being shaped, at its upper and lower portions, for the reception of, and cooperation with, baille elements of agitator means, which will be lateI1 described. The tub has a somewhat hemispherical or bowl shaped bottom portion 19' and an inverted, somewhat hemispherical top portion 19, the sides of these portions forming parts of the side walls of the tubv and are joined together by a substantially straight side wall portion 19'.

The tub has a portion 8| pressed upwardly at the tub bottom (Figs. 1 and 6). A disc-like metal mounting element B2 is provided outside the tub bottom, and the agitator 83, having a disc-like base 84, is provided inside the tub bottom, these elements extending about the portion and conforming to and being secured to the tub, as by rivets.

The bottom mounting 82 has a recess for the reception of the upper end of a drive shaft 81 which is operatively connected to the mountingr 82, this connection being indicated by a pin 88. The lower portion of the tub also communicates, through a bushing 89, with the valve 36, for controlling the diaphragm movements as will be further set forth.

At about its vertical central portion the tub 28 is provided with a peripheral channel 92,

Fig. 1, openat the inner side of the tub and constituting part of means for attaching the diaphragm 33 to the tub, as will further appear.

The top of the tub has secured thereto a metal casting or neck portion 96, of cylindrical or ringlike character, having a depending tapered flange 91 conforming, at its outer surface, to the inner surface of the sheet metal body 19 of the tub, and having its inner surface gradually merging and curving into the curved inner surface of the sheet metal body whereby to preserve the gradually rounded inner top contour of the tub. The neck portion of the casting 96 has an outwardly projecting peripheral flange |02, in which is a top groove |03. A plurality of peripherally spaced ducts or outlet ports |06 extend diagonally downwardly and outwardly through the casting 96 from the groove |03 to the exterior of the tub, for allowing water from the tub to drain into the housing 21 through the radially narrow peripheral' space between the flange 11 on the shell 12 and the upper part of the sheet metal tub.

A plate-like element of the lid 3| is constructed of sheet metal pressed to inverted shallow substantially dish shape. The metal of the plate at its periphery encircles a ring I3, in this instance, of square cross section, which forms a flange that overlies and cooperates with the flange |02. Mounted concentrically with the ring ||3 is a frame |32 between which and the plate is disposed a rigid screen |33 conforming in general to the shape of the plate l The frame |32 is appropriately secured to the plate and has peripherally spaced, downwardly extending ducts |34 which Vcommunicate at their lower ends with the peripheral groove |03 and at their upper ends with the screen openings.

The screen |33 is of large mesh and also has radial top grooves or corrugations |35 which, when the clothes mass is pressed against the screen by the diaphragm, form gutters or channels for better draining oi the water outwardly through the space between the ring |32 and plate lll, downwardly through the ducts |34 into the top annular groove |03, and thence through the ducts |06, into the housing 21, as above mentioned. Before the clothes are tightly pressed against the screen, the main bulk of the wash or rinse water being displaced by the diaphragm flows freely outwardly through various parts of the screen, irrespective of the grooves |35, thence into the ducts |34 and outwardly from the tub as stated. Although the drawings show the ducts |00 and |34 substantially in register, the groove |03 and the ducts |06 may be of sufficient capacity to carry off the water admitted to the groove by the ducts |34 irrespective of the locations of the latter around the groove.

The lid 3| is removably held upon the tub by a clamping ring |1 of channel section, which embraces the lid ange ||3 and the tub flange |02, when the lid is in place on the tub. The ring is split, as at one position about its periphery and provided with operating means for peripheral expansion of the clamping ring to release the lid for opening, and for peripheral contraction of the ring for locking ,the lidV in closed position.

At the top outside center of the lid 3| an aperture therein is surrounded by a nipple |36 (Fig. 1) attached theretoy on which is a grooved ferrule |31. A cap like member |38 has rotative water sealed relation to the nipple, being provided with a spring clip |43, the inner end of which removably extends through an opening in the cap and into the groove of the ferrule. The cap |38 is connected, by a coupling |39, to a flexible conduit |40 of the metal armored type. The conduit extends through the bushing 18, and between the housing 21 and the tub 28, to a nipple |4| in the bottom wall of the housing. Water is supplied to the conduit |40 from an inlet connection |42, secured to the bottom disc 56, through a hose or conduit |44, which extends through an opening in the shell 51, to a valve of an automatic control mechanism (not shown), and from the valve through a hose or conduit |49, extending through an opening in the shell 51, to the nipple |4I, to which the conduit |40 is connected. A source of heated water may be connected to the inlet |42.

A section |5| of the flexible armored conduit |40 (Fig. 1) operates as a hinge, or iiexible mechanical connector, between the housing 21 and the lid 3|, to prevent complete separation of the lid from the tub when the lid is open, and to hold the lid in convenient position for closing the tub. Also, the section |5| of the conduit |40, may move o back and forth through the bushing 18 to avoid buckling of the conduit and to better control the action of opening and closing the tub.

Although agitation or stirring of the clothes and water may be obtained by agitating means operating relative to a stationary tub, in the example here given it is obtained by bales fixed to the oscillating tub whereby the water and clothes are given a special tumbling action during washing, substantially as indicated by arrows D; and, during rinsing, combined with, or augmented by, the action of fresh incoming water in the direction of an arrow E, shown at the top of Fig. 1. Either or both sets of bales 32 and 34 may be employed in either operation, and either or both may be formed in the tub by being pressed therein.

The upper baies 34 are herein shown as integral parts of the top metal casting 96, although they may be separately attached thereto, or to the tub, or constitute parts of the tub body as indicated, and may be varied in number, two being shown, located at opposite sides of the tub. They are, as better illustrated in Figs. 2 and 3, of fin-like character rounded at the inner thinner edges |56, and each having a tapered side |51 merging gradually into the inner surface of the tub body, while the opposite side |58 of each baie is straight, presenting a flat, radially extending side. The at sides of the baffles 34 face in the same direction with respect to the direction of tub oscillation, for a purpose to be referred to later. The edges |56 slope downwardly and inwardly from the casting 96, substantially as chords of the cross sectional arc of the tub body 19, to a position close to the mid channel 92, where they are suddenly sloped into the tub surface.

The broad sides of the baffles extend in a general radial direction to the tub axis at any horizontal section, but are inclined upwardly, and, longitudinally, they slope relative to the vertical at an angle of about twenty-five degrees, as better seen in Fig. 2. The cross section of each of thesebales is substantially as shown in Fig. 3, the apparent thicker section thereof indicated in Fig. 1, being caused by the vertical cut therethrough along the line l-I of Fig. 2. Ihese baifles slope oppositely, so that this section also requires that the upper part of the left hand baffle, and the lower part of the right hand baille. as viewed in Fig. 1, be shown in full lines, and that the lower part of the left hand bale and the upper part of the right hand baffle be shown in dot and dash lines, since looking into the bales along the line of Fig. 2, as is actually the case in Fig. 1, would only show the upper part of the left hand baffle, and the lower part of the right hand bale, as will be understood.

The lower agitator 83 (Figs. 1, 4, 5 and 6) comprises the dish-like base 84, on which the baffles 32 extend radially from the center. At the upper edge the baies are rounded, and the sides divergingly taper to the base. In vertical plane outline, each baille 32 is of generally curved or rounded contour conforming somewhat to the lower recess of the tub, and has an outer enlarged portion |63. The baffles 32, in relation to such recess and to the globular sides of the outer portions of the tub, cause the water and clothes mass to be impelled radially outwardly and upwardly along the sides of the tub, which mass if uninterrupted, would immediately move downwardly in the center of the tub, round and round. However, at the top the clothes encounter the additional agitation produced by the upper bailles 34,. which will break up the cycle produced by the lower agitator, and keep the clothes well spread out in the water so that all clothes receive 6 the full agitation, which is a combination of actions.

I'he bailies 34, by the length and the angular disposition thereof, tend to and do lift the clothes along the baiiies, and toward the center of the tub, and to turn the clothes over. 'I'he baffles are of greatest radial depth midway of the length thereof so that as the tub oscillates on its vertical axis, the greatest force exerted upon the clothes is radially inwardly along and opposite these mid-sections. However, the sections of the baffles 34, above the mid-portions, exert a more or less downward component of movement toward and along the axis of the tub, and the sections of the baffles, below the mid-portions, exert a thrust radially inwardly. The result of all of these forces is to cause considerable agitation of the clothes in the upper portion of the tub as they are moved inwardly, and before they are carried downwardly in the center to be again subjected to the action of the lower agitator.

During rinsing, the central downward movement is augmented by the fresh rinse water entering the tub, in the direction of the arrow E. At the same time, the fresh water is introduced and mixed in definite and symmetrical manner, ensuring its diffusion to al1 parts of the clothes mass, and avoiding rinsing more at one part than at another, as will appear.

In addition to the described. actions of the upper baffles 34, they perform a further function in augmenting the thorough cleansing action on the entire clothes mass. Since the tub oscillates on a vertical axis, and the baffles have flat sides facing in the same direction, as these flat sides move forwardly, they produce a different agitation from the broad sides or faces and also engage the clothes mass and move it part way around the tub circumferentially to occupy a different position with respect to the main forces exerted by the baffles. As the bafiles 34 move in the reverse direction the clothes mass slides off the slanting faces thereof. The next forward motion of the at sides of the baffles engages a different portion of the clothes mass, and thus the clothes are moved around the vertical axis with a step by step motion, in addition to all the other movements imparted thereto.

The power unit herein described is the main drive motor and mechanism for oscillating the tub to agltate the clothes. The drive shaft 81 (Fig. l) is journaled in a relatively long sleeve bearing 23| having exterior screw threads, whereby it is vertically adjustably mounted in tubular post 232, and it is fixed in adjusted position by a nut 233. The post 232 has a top flange bolted to the bottom 63 of the tub housing 21, and a bottom flange bolted to the bottom disc 56. The drive shaft 81 has a lower portion 24| of reduced diameter providing a shoulder, which rests on a ball bearing 242 that is held in place by a gland 243 through which the shaft portion 24| extends. Below the portion 24|, the shaft is of square cross section, which terminates in a threaded end 244. A sleeve 241 of a crank arm 248 (also Fig. 4) nts upon the squared portion of the shaft 81, and is pivotally connected to one end of a link 252. The other end of the link 252 is pivotally connected toa worin wheel 256, the pivotal connection being eccentrically located thereon. A shaft 251, of the worm wheel 256, is mounted in the bottom of a lower casing 26|, which also carries a bearing '262 for the sleeve 241. An upper casing 263 hasa bearing 7 264 for the sleeve 261. The casing portions 26| and 263 have cooperating outer anges 265 secured to each other, as by bolting. This mechanism is supported upon the lower end of the shaft 81, as by a washer 266 and by a nut 231, which is locked in place.

A worm screw 263, on a shaft 269, engages the worm wheel 256, and is driven by a motor 21|. through pulleys 212, and a belt 213. The motor 21| is supported on an arm 216, which is pivotally mounted on a projection extending from the upper casing 263. A screw 282, mounted on the casing 26| cooperates with the arm 216 for adjusting the position of the motor on its pivot mounting, to regulate the tension in the belt 213. In operation, when the motor 21| is energized, it causes continuous rotation of the worm wheel 256, which is translated into oscillating motion of the crank arm 248 and consequently, of the drive shaft 31 and the tub 28.

A casing for the drive mechanism comprises an upper shell 283 secured to a lower pan 281, as by bolts 283. The pan 231 is secured to the gear casing ESI- 263, as by the nut 231 and a nut or nuts 233 on the lower end of shaft 251. The bolts 263 also secure laterally extending plates 29| to the pan at radially opposite parts thereof. The plates 28| are connected to leaf springs '232, of the shock absorber devices 62, which, in turn, are secured to two of the legs 3| oi the machine. Near the ends of its strokes, the oscillatingr structure has its motion damped by the yieldability of the springs 262 in a direction circumferentially of the drive shaft, the springs being rigid in the up and down direction.

The diaphragm 33 hereof is made of high grade durable soft rubber or other material, and is molded or formed such that, in its contracted or relaxed state, it not only conforms closely to the shape of the tub, but also to the agitator baiiles 32, and to other parts of the lower agitator 83.

The diaphragm is somewhat semi-spherical in shape, having an upper edge peripheral bead |61, Fig. 1. An expansion ring |1| engages the upper peripheral part of the diaphragm, just under the bead |61, pressing the same into the channel 62 formed in the tub side wall to mount the diaphragm with a water-tight connection to the tub.

At its bottom, the diaphragm is further provided with portions 268 of inverted substantially channel section closely conforming to, and in relaxed condition :dtting over the balles 32. During expansion, the diaphragm lifts oi the bottom of the tub, rising from the baiiies and, since it does not turn relative to the tub, returns easily and accurately to position fitting the baffles. The now of water to and from the space between the diaphragm 33 and the bottom of the tub, to expand and contract the diaphragm, is controlled in part by the diaphragm valve 36, indicated in Fig. 1, water under pressure being admitted by the valve 36 through the bushing 89 to position under or behind the diaphragm, to push or expand the diaphragm upwardly in the tub.

As the clothes are compressed between the diaphragm and the screen |33, the wash or rinse water escapes from the top of the tub, as above described. Near the end of the drying operation, the pressure behind the diaphragm builds up to that of the incoming fluid. When the water supply has been stopped by the aforesaid automatic control mechanism, a bleeder valve of the valve 36 allows the water pressure in the valve casing to drop gradually. After a certain amount of.

bleeding, the valve 36 opens to the full open position allowing the water behind the cli-x aphragm to flow, aided by contraction of the diaphragm 33, into the bottom of the housing 21, from which it drains through the drain pipe 62. The Water pressure applied behind the dia-.- phragm during expansion of the latter being substantially uniform, the pressure developed in the drying and flushing operations are readily calcu.- lable, so that the valve 36 may be properly adjusted to eiect the desired draining, quickly and in proper sequence.

The pressure maintained by the adjustable bleeder of the valve 36 also enables regulating the duration of the time period of high pressures on the clothes, that is to say, the rate of bleeding can be adjusted to determine the length of time before the valve 36 opens to dump the water from behind the diaphragm and, therefore, there may be a period of sustained higher pressures during the drying operation.

The water supply to the diaphragm valve 36 is from an inlet pipe 2|! (Fig. 1), secured to the disc 56 by a clip 2 2, through a conduit 2 |6, which extends through an opening in the shell 51, to a valve of the automatic control mechanism. From the latter valve, the water is conducted through a conduit lai, which enters the shell 51 and extends upwardly through a nipple 226, in the bottom wall of the housing 21, whereupon it is formed into a flat spiral section 221, of about two turns, surrounding the drive shaft 81, before connecting to the diaphragm valve 36.

Special provisions are made to insure complete draining of the water from behind the diaphragm 33, and to insure against accidental and premature closing of the opening to the diaphgram valve. To this end, the lower face of the base 64 of the lower agitator has an annular groove 228, Figs. 1 and 6, leaving a peripheral portion 229. The head of the mounting bushing 89 for the diaphragm valve 36 is received in the groove 228. The base 84 has apertures 234 therethrough communicating with the groove 228, and the peripheral portion 223 has apertures 232 also communicating with the groove 228. When water is admitted behind the diaphragm, it passes through the apertures 236 and 232 to start the diaphragm expansion. When water is being expelled from below the diaphragm, it drains through the apertures 236 and 232 into the groove 223 and from the latter through the valve 36 to the tub housing 21, but without danger of the diaphragm fouling the opening into the diaphragm valve 36.

Operation At the beginning of the operation of the machine the operator places the dry clothes in the tub. The machine is next lled with water and soap, washing powder or water softener added, after which the lid 3| is locked in place.

'The motor is started which oscillates the tub 21 and agitation of the clothing and water as well as circulation of the clothes is produced as described above. At the end of a selected washing period, the control mechanism may operate to admit water behind the diaphragm 33, through the valve 36, to a flushing operation in this case, in which the diaphragm lifts the clothes and wash water toward the top of the machine, so that the wash water is gradually forced out through the drain openings |34, in the lid, and |66 in the tub. Thus, any scum and matter,

which has accumulated on top of the wash water, is ushed out of the machine. At this time, the agitation of the machine has not been stopped. It may be stopped when the diaphragm has lifted the clothes and Water past the center of the tub, which is about one-half or two-thirds of the flushing cycle, so that agitation continues, by means of the upper baies, whereby the accumulated matter` also is liberated from the clothes to float oi with the water.

Inflation of the diaphragm may continue, until substantially all of the wash water has been extracted from the clothes, at which time, the valve 3E operates to empty the water from behind the diaphragm, and the diaphragm returns to its lower position shown in Fig. 1.

By this time, the control mechanism has operated to admit water to the tub through the center of the lid, which is the beginning of the rinsing operation. When suicient water has been admitted to the tub to make agitation of the clothes and water of some benefit, which is about onethird of the time consumed by the rinsing operation, agitation is re-started. Agitation continues during the remainder of the rinsing operation, and for a suicient length of time for the tub to completely ll with water and also to overflow through the ducts |34 and |06 for a suflicient interval of time to thoroughly rinse the clothes.

At the conclusion of the rinsing operation, the control mechanism again opens the diaphragm water valve, to again expand the diaphragm to eject the rinse water, and this is the beginning of the drying operation. Agitation is continued further, until the diaphragm is above the center of the tub, and preferably during about half of the period of time for this particular operation of the diaphragm. The expansion of the diaphragm continues to bring about drying of the clothes by compressing the same against the upper portions .of the tub and its cover, until substantially all of the water is extracted from the clothes whereupon the supply of water behind the diaphragm is shut oi, and the action of the diaphragm valve 36 will again operate to dump the Water from behind the diaphragm.

Other modications may be made in the arrangement and location of parts within the spirit and scope of my invention, and such modifications are intended to be covered by the appended claims.

I claim:

1. In a washing machine, a tub, means for moving said tub about an upright axis, separated Ibaiile members for agitating the contents of the tub and respectively located in the regions of said tub above and below the center thereof, a diaphragm mounted in said tub, and means for causing the diaphragm to move the contents'of the tub away from the lower baiiies whereupon only the upper baiies will be effective to agitate the contents of the tub as the tub is moved.

2. In a washing machine, a tub having an upper access opening, means for oscillating said tub about an upright axis, baiiies in said tub for agitating the contents of the tub when it is oscillated, a lid for said opening, a liquid inlet connec-a tion to the lid of the tub, said connection comprising a tube mounted on said lid and a cap swivelled upon said tube, and a exible hose connected to said cap.

GEORGE C. GRAHAM.

References Cited in the le of this patent UNITED STATES PATENTS Number Name Date 33,146 Harsha Aug. 27, 1861 408,797 Cronk Aug. 13, 1889 686,917 Baker Nov. 19, 1901 821,85'0 Bierley May 29, 1906 1,112,892 Chase Oct. 6, 1914 1,319,314 VVearne Oct. 21, 1919 1,542,292 Eddy June 16, 1925 1,547,266 Robe July 28, 1925 1,563,136 Altorfer Nov. 24, 1925 1,600,249 Sande Sept. 21, 1926 1,611,310 Grant Dec. 21, 1926 1,627,931 Schroeder May 10, 1927 1,629,762 Woodrow May 24, 1927 1,633,796 Sinclair June 28, 1927 1,665,959 Graham Apr. 10, 1928 1,747,293 Geldhof Feb. 18, 1930 1,764,476 ISmith June 17, 1930 1,777,662 Engberg Oct. 7, 1930 1,828,908 Perkins Oct. 27, 1931 1,849,896 Weiman Mar. 15, 1932 1,999,353 Blake Apr. 30, 1935 2,168,068 Loweke Aug. 1, 1939 2,231,189 Kirby Feb. 11, 1941 2,265,516 Chayie Dec. 9, 1941 2,296,258 Breckenridge Sept. 2'2, 1942 2,300,421 Henderson Nov. 3, 1942 2,331,897 Dyer Oct. 19, 1943 2,335,560 Crane Nov. 30, 1943 FOREIGN PATENTS Number Country Date 343,281 France Aug. 2, 1904 400,734 Germany Aug. 21, 1924 648,293 Germany July 28, 1937

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