US2733958A - warren - Google Patents

Description

Feb. 7, 1956 WARREN 2,733,958

WATER SPRINKLER Filed June 8, 1955 A 2 Sheets-Sheet l fimnv GLENN M/ARRfN INVENTOR.

Feb. 7, 1956 H. G. WARREN 2,733,958

WATER SPRINKLER Filed June 8, 1953 2 Sheets-Sheet 2 3 INVENTOR.

ATTORNEY HARRY GLEN/v WARREN United States Patent This invention relates to a water sprinkler, and particularly to the type of sprinkler adapted to oscillate between fixed limits and water a predetermined sector of a lawn.

Conventional lawn sprinklers of the pivoting or oscillating type are subject to numerous disadvantages tending to make them unsuitable for many types of operation. Some such sprinklers, for example, have a side spray which may wet undesired locations such as sidewalks, and which prevents an operator from approaching the sprinkler, in order to move it to a new location, without turning ofi the water. Furthermore, many sprinklers of the oscillating type are characterized by an objectionably loud sharp click at the end of each oscillation. In addition to the above, many sprinklers presently known are not adjustable to vary the angle of the sector to be sprinkled, are not adjustable as to rate of oscillation except by varying the volume of sprinkled water, and do not efiect an even distribution of water over the area. More importantly, certain types of oscillating sprinklers tend to assume a dead center position at which oscillation is stopped, so that further pivoting movement is dependent upon manual actuation of the sprinkler head past the dead center position.

In view of the above factors characterizing the field of oscillating lawn sprinklers, it is an object of the present invention to provide an oscillating sprinkler head having overcenter means to prevent the head from assuming a dead center position, so that continued oscillation is assured under all conditions of operation.

A further object of the invention is to provide a sprinkler which is substantially noiseless in operation, is adjustable as to speed without varying the water pressure or volume, and is readily adjusted to sprinkle from a fixed position to any sector of a complete circle.

An additional object is to provide an automatic sprinkler effecting an even water distribution over the area being covered, and free from objectionable side spray tending to deter an operator from approaching the sprinkler when the water is on.

A further object is to provide a sprinkler head which is simple and reliable in operation in that it has only a single large jet, to minimize the possibility of clogging, and is provided with a novel thrust bearing structure to insure substantially frictionless pivoting and long life.

These and other objects and advantages of the invention will be more fully set forth in the following specification and claims considered in connection with the attached drawings to which they relate.

In the drawings:

Figure 1 is a top plan view of the operating portion of the sprinkler;

Figure 2 is a side elevational view of the showing of Figure 1;

Figure 3 is a transverse sectional view along line 3-3 of Figure 1 and illustrating the reversing arm and overcenter yoke;

'ice

Figure 4 is an end view at line 4-4 of Figure 2 and illustrating the deflector member;

Figure 5 is a perspective view of the deflector;

Figure 6 is a vertical section along line 6--6 of Figure 1 and showing the internal passages and bearings of the sprinkler head;

Figure 7 is a fragmentary view along line 7-7 of Figure 6 and as viewed in the direction of the arrows;

Figure 8 is a plan view illustrating the mounting of the working components of the sprinkler on a base, the showing being reduced in size;

Figure 9 is an elevational view of the showing of Figure 8; and

Figures 10 and 11 are detail views of the deflector.

Referring to the drawings, the sprinkler is seen to comprise a base 10 (Figures 8 and 9), a stationary journal boss 11 extending upwardly from the base, a nozzle 12 rotatably associated with the journal boss, and deflector means 13 mounted on the upper portion of nozzle 12 and movable between close limits. The invention further comprises means 14 to adjust the limits of movement of the deflector means and thus the speed of pivoting of nozzle 12, an overcenter yoke 16 to prevent the deflector means from assuming a dead center position resulting in cessation of nozzle movement, and stop means 17 which cooperate with the overcenter yoke and are operable to adjust the sector of nozzle oscillation and thus the area of lawnbeing watered.

Referring to Figures 8 and 9, the base 10 is illustrated as a three-legged type having two solid legs 19 and a hollow leg 20, the latter being adapted with a coupling 21 for connection to a water hose. The hollow center portion 22 of base 10 is internally threaded to receive the vertically projecting journal boss 11, the lower end of which is provided with external threads 23.

As best shown in Figures 2 and 6, the journal boss 11 is formed above threads 23 with a hexagonal portion 25 for a wrench hold, and at its upper end with a relatively large diameter flange portion 26 which serves as a mounting for the stop means 17 as will be described subse quently. An axial passage 2'7 is provided in the journal boss to receive a vertical shaft tube 28, the passage 27 opening out into a ball chamber 29 inwardly of flange 26.

It is a feature of the invention that substantially frictionless thrust bearing means are provided to absorb the pressure of water passing upwardly through tube 28 and out nozzle 12, these means comprising a plurality of stainless steel balls 31 mounted in ball chamber 29 circumferentially of shaft 28. When there is no water passing through the nozzle, the balls 31 seat partially on the correspondingly curved lower wall of ball chamber 29, and partially on a conical ball seat 32 formed on the shaft tube. When, however, water is passing through the sprinkler, pressure of the water against nozzle 12 operates to lift the nozzle and shaft tube 28 until the balls 31 seat on a horizontal thrust washer 33 mounted across the upper end of the journal boss and retained in place by a snap ring 34.

With the above arrangement, the nozzle 12 and shaft tube 28 may oscillate without substantial friction, the water pressure being absorbed by the balls 31 riding between bearing cone 32, thrust washer 33, and the cylindrical outer wall of ball chamber 29. The lateral bearings for the shaft tube 28 are provided at the open center of thrust washer 33 and at the necked down lower end 36 of the journal boss. Suitable sealing means, taking the form of a packing ring 37 and retaining ring 38, are seated in end 36 to prevent leakage of water into ball chamber 29 and around washer 33 to the atmosphere.

The nozzle 12 comprises a generally cylindrical base portion 40 and a radial arm portion 41 which extends outwardly and upwardly for a substantial distance from 'arsasss the base, the arm being, for example, at a one hundred five degree angle from the vertical shaft tube.

The nozzle base 40 is threaded downwardly over the upper end of shaft tube 28, and is formed with a vertical "water passage 42 Whichcommunicates with a relatively smaller water passage 43 extending axially through arm 41. A Water path is thus formed from a hose through leg 20 of base 10, base center 22, shaft tube 26, and

passages 42 and 43 for distribution over the lawn being sprinkled. At the outer end of passage 42, which ispreferably of the same internal diameter as shaft 2%, is a bushing 44 press fitted into arm 41. Bushing is shaped to provide a reduced diameter, yet relatively large and clog-resistant, discharge opening for the water jet.

The deflector means 13 comprise a shaft 45 journaled parallel to arm 41, and in spaced relation above it, by means of journal lugs 46 and 47 integral with the inner andouter ends of the nozzle arm, a deflector i3 dependmounted on shaft 45 as by a transverse pin 52 (Figure 2), and with a deflecting portion 53 disposed adjacent the discharge opening at the outer end of arm 41. Deflector portion 53 takes the form of a triangular block having a substantially vertical apex edge 54 disposed at approximately the center of the jet discharge opening. The two deflecting faces 56 and 57 of deflector portion extend, as shown in Figure 7, from apex 54 and to the outer edge of the block, the included angle between the deflecting faces being on the order of thirty degrees. When apex 54 is exactly at the center of the nozzle opening, the water jet divides equally on faces 56 and 57 and, the deflection angles and volumes of the jet components being equal, there is no resultant pivotal force in either direction. When, however, the apex is moved to one side of the axis of passage 43, the water jet will divide into unequal portions which will deflect at equal angles on opposite sides of a vertical plane containing the jet axis. There will then be a resultant reaction force tending to pivot the nozzle in a direction away from the component of the jet containing the largest volume of water. 'It follows that when the apex is to the left of dead center as viewed in Figure 4, the nozzle will rotate clockwise as viewed from the top (Figure 1), and when the apex is at the right of center the nozzle will rotate counterclockwise.

Referringparticularly to Figures 2 and 3, the necessary .movement of deflector43 is effected through shaft 45 by means of reversing arm 49, which is generally hookshaped as viewed in Figure 3. The upper or shank end ti of the reversing arm is mounted on shaft 45, and the lower or hook portion of the arm is curved beneath nozzle portion 41 as shown, sufficient clearance being provided to permit'substantial pivotal movement of the reversing arm on its shaft. Shankend 6b of reversing arm 4? serves a second function of limiting the axial displacement of deflector shaft 415, so that deflector 48 is always spaced a sufiicient distance in advance of nozzle 41 to prevent rubbing contact. For this purpose the shank oil, which is secured on shaft 45 by a set screw 61, is disposed between the inner journal lug 46 and a stop ear 62 projecting from the upper portion of nozzle base 49 adjacent the end of shaft 45.

The speed control means 14 which determine the limits of deflection of reversing amt-i9 by the overcenter yoke 16 and stop means 17, to be described subsequently, comprise a screw '64 threaded parallel to nozzle armdl through a depending lug 65 formed integral with the lower inner portion of the nozzle arm. The inner end of speed control screw 64, rela'tively adjacent nozzle base 40, is generally conical in shape 'andexte'nds through a circular hole 66 formed in the lower portion ofreversing arm 49 as best shown in Figure 3. With this arrangement, the amount of deflection of reversing arm d9 may be precisely controlled by merely turning the adjustment screw 64 to either advance or retract the conical screw end relative to hole 66. The off-center position of the deflector apex 54, and thus the amount of reaction force and speed of nozzle pivoting, are in this way controlled with great accuracy.

As shown in Figure 6, the center portion 67 of screw 64 is not threaded, and is adapted to cooperate with a suitable spring clip 68 mounted around it and in a vertical slot 69 in lug 65. Clip 68 serves to prevent complete displacement of the adjustment screw from the lug, and also to prevent excessive threading of the conical end into reversing arm aperture 66.

The overcenter yoke 16 comprises a generally annular horizontal body portion 71 mounted loosely around shaft tube 23, and a horizontal shelf portion 72 formed integral with body '71 beneath reversing arm 49. The body '71 is pivotally connected, remote from shelf 72, to a boss portion "73 of nozzle base 40, this connection taking the form of the vertical screw 74 and bushing 75 illustrated in Figure 6. The shelf portion 72 of the overcenter yoke serves as a mounting for a pair of laterally spaced ears '76 and 77 (Figure 3) adapted to cooperate with a lug 78 formed on reversing arm 49 beneath hole 66. An overcenter spring 83, for example of the type employed on the shutters of inexpensive box cameras, is mounted between nozzle base 4i) and yoke shelf 72 to insure that the yoke never remains at dead center but instead only stops at one of the extreme positions illustrated in solid and dashed lines in Figure 3.

The stop means 17 comprise a pair of vertically spaced annular spring elements 32 and 83 mounted, respectively, in upper and lower peri heral grooves in flange 26 of journal boss The ends of the spring SZ'project radially from the annular body of the spring to form a stop arm S i, While the ends of spring 83 project correspondingly to form a stop arm 85. Each of the stop arms 8d and d5 may be set at any rotated position merely through manually shifting, the spring pressure between each spring body and its mounting groove being sufiicient to frictionally maintain the stop arm at the desired angle. Stop arms 84 and 35 cooperate with a vertical yoke arm 37 which depends from yoke shelf portion 72 midway between ears 7'5 and 77. With the described arrangement, the yoke i6, and thus vertical arm 87, pivots with nozzle 12 due to action of the overcenter spring 80, and until the art $7 engages one or the other of stop arms $4 and When a stop arm is engaged, the .yoke is held and the nozzle moves relative thereto until the overccnter spring 86' becomes operative to throw the yoke to the opposite position. An ear 7a or '77 thenacts through lug '78 to change the position of reversing arm d9, which acts through shaft 45 to pivot deflector element 4% and in this way reverse the direction of nozzle rotation. it may thus be seen that the sector of rotation of the nozzle 12, and thus the area of lawn covered,may be precisely controlled merely by shifting the stop arms h and 85 to any desired position, so that the angle of nozzle pivotingmay be varied between zero and three hundred sixty degrees.

In the operation of the automatic sprinkler head, let it be assumed that overcenter yoke 16 is initially in the left or solid line position shown in Figure 3, "so that car '77 acts on lug 78 to maintain reversing 'arm 49 in its clockwise pivoted position. At this time the nozzle 12 may be in any rotated position, for example midway be- 80. Prior to the passing of water through the sprinkler the shaft tube 23 isin the 'lower'position shown in Figure 6, with the bearing cone 32 resting on ashoulder-in journal boss 11 and with the bearing balls 31 out of engagement with thrust washer 33.

When a hose is connected to the coupling 21, and the water turned on, water passes through hollow leg and base center portion 22, then upwardly through shaft tube 28 and into vertical passage 42 in nozzle base 40. As the water strikes the upper end wall of passage 42 it exerts a substantial lifting force which elevates the nozzle 12 and shaft tube 28, so that bearing cone 32 is lifted to shift the bearing balls 31 upwardly into engagement with thrust washer 33. The thrust of the water is thus taken entirely by the bearing balls, and a substantially frictionless bearing is provided by the bearing balls which roll between cone 32 and the thrust washer. From passage 42 the water is deflected into the axial passage 43 in nozzle arm 41, this passage being of substantial diameter to provide a relatively large single jet of water.

As the water discharges from passage 43 it divides along the apex edge 54 of the triangular block 53, so that the single water jet is separated into two components one of which impinges on face 56 and the other on face 57 illustrated in Figure 7. Because of the initial positioning of reversing arm 49 as described above, the apex edge 54 is to the left of center as viewed in Figure 4, or in the upper position as viewed in Figure 7. The jet component impinging upon face 57 (Figure 7) will therefore be of larger volume than the component impinging upon face 56. It follows that the reaction force against face 57 will be greater than that against face 56 and a resultant pivotal force will be created tending to rotate the nozzle clockwise as viewed from above in Figure l. The nozzle will then rotate clockwise as will the overcenter yoke 16 which at this time is held by overcenter spring 80 against movement relative to the nozzle. Clockwise rotation will continue until vertical yoke arm 87 comes into engagement with stop arm 84 to prevent further pivoting of the overcenter yoke, so that lug 78 on reversing arm 49 moves out of engagement with yoke ear 77 and in the direction of the now stationary ear 76. When ear 76 and lug 78 come into engagement the reversing arm 49 is pivoted to the dashed line position shown in Figure 3, so that deflector shaft 45 and thus deflector 48 rotate until apex edge 54 is shifted to the opposite side of the discharge opening from passage 43. The component of the water jet deflected off the face 56 will then be of larger volume than that deflected off face 57 and a resultant force is created in the reverse direction. The nozzle then pivots counterclockwise, as viewed from the top, until yoke arm 87 engages stop arm 85 to reverse the action.

It is a feature of the invention that the speed of the pivotal movement, for any given water pressure, is dependent entirely upon the distance that the apex edge 54 is moved away from a vertical plane containing the axis of passage 43 and of the discharging water jet. When the apex edge is only a slight distance off center, the volume of water deflected off the corresponding face 56 or 57 will be only slightly greater than that deflected off the opposite face, so that a relatively small resultant reaction force will be created and the speed of pivoting will be correspondingly slow. When, on the other hand, the apex is moved a substantial distance from center, the relatively great difference in water volume will result in a correspondingly increased reaction force and the pivoting movement will be rapid. As previously described in detail, the limits of movement of apex edge 54 are accurately determined by speed adjustment screw 64 the conical end of which is inserted in the hole 66 in reversing arm 49. When the conical end of screw 64 is threaded a substantial distance into hole 66, the amount of pivoting of the reversing arm, and thus of deflector 48, will be extremely small and the nozzle travel will be slow. To increase the speed of nozzle movement, the screw 64 is turned in a direction to retract its conical end from the reversing arm hole and increase the distance of permissible movement of the reversing arm and thus of the deflector. The above action is to be compared with many sprinkler heads in which the speed of nozzle rotation is governed by the water pressure, so that in order to decrease the speed it is necessary to decrease the water volume which is undesirable in many instances.

The amount of noise resulting from the reversing action is extremely small as compared to conventional sprinklers. This is because the only metallic contact is between vertical yoke arm 87 and the stop arms 84 and 85, as well as between one or the other of ears 76 and 77 and reversing arm lug 78, these contacts being somewhat cushioned due to the resilience of the stop arms. When the nozzle is pivoting at relatively high speed the reversing arm lug 78 will normally engage the yoke ears while the yoke arm 87 is in contact with a stop arm 84 or 85. When, however, the nozzle travel is slow, the overcenter spring 80 may operate to pivot yoke 16 out of engagement with a stop arm 84 or 85 prior to the engagement of lug 78 with the opposite car. In the latter situation, the amount of noise is reduced since the force exerted by the water reverses to cushion the reversing action and results in substantially noiseless operation. In any event, the spring 80 and yoke 16 insure that the reversing arm 49 will always be in an extreme position so that the deflector 48 will remain otf center and continued nozzle pivoting assured.

Referring to Figures 10 and 11, it is a feature of the invention that the upper part of the jet or cone of water emanating from nozzle 12 is cut ofi or flattened in a highly novel manner, so that water in this upper cone component travels a further distance and improves the pattern of water distribution. This is accomplished by forming deflector body 51 with longitudinal deflector faces in the form of triangular undersurfaces lying in a plane parallel to and spaced slightly above the passage 43. The space between the inner edges of surfaces 90 and the deflector faces 56 and 57 is formed to provide grooves 91. .In the operation of this portion of the sprinkler, the upper components of the jet or cone of water are deflected along, and guided by, the surfaces 90 and grooves 91 so that a flattened cone is provided and water distribution improved.

While the particular apparatus herein shown and described in detail is fully capable of attaining the objects and providing the advantages hereinbefore stated, it is to be understood that it is merely illustrative of the presently preferred embodiments of the invention and that no limitations are intended to the details of construction or design herein shown other than as defined in the appended claims.

I claim:

1. An automatic sprinkler head, which comprises a stationary base having an upwardly extending journal boss, an axis tube journaled in said boss, a nozzle mounted on the upper portion of said axis tube and extending in a generally horizontal direction, said nozzle having a water passage communicating at its inner end with said axis tube and terminating at its outer end in a relatively large discharge opening, a deflector shaft journaled on said nozzle and generally parallel thereto, a deflector mounted to the deflector shaft at the outer end thereof and disposed adjacent said discharge opening, said deflector having angularly disposed deflector faces adapted to divide the water jet from said discharge opening into two components one of which is deflected to one side of a vertical plane containing the axis of said jet and the other of which is deflected to the other side of said vertical plane, a reversing arm mounted to the deflector shaft at the inner end thereof and movable to shift the position of said deflector, adjustable speed control means to limit the movement of said reversing arm to between first and second positions at which the volume of water in said one jet component is alternately greater and lesser than the volume in said other jet component, said speed control means comprising a screw 'threadedly mounted for movement with said nozzle and having a tapered end loosely inserted in a "boss, an axis tube journaled in said boss, the upper end of said journal boss being recessed to provide a ball chamber, a plurality of balls in said ball chamber around said axis tube, a ball seat on said axis tube beneath said balls, a thrust washer mounted over the upper end of said journal boss, a nozzle mounted on the upper portion of said axis'tube and extending in a generally horizontal direction, said nozzle having a water passage communicating at its inner end with said axis tube and terminating at its outer end in a relatively large discharge opening, said thrust washer serving as a racefor said balls when said nozzle, axis tube and ball seat are elevated due to reaction of Water against said nozzle, a deflectorshaft journaled on said nozzle and generally parallel thereto, a deflector mounted to the deflector shaft at the outer end thereof and disposed adjacent said discharge opening, said deflector having angularly disposed deflector faces adapted to divide the Water jet from said discharge opening into two components one of which is deflected to one side of a vertical plane containing the axis of said jet and the other of which is deflected to the other side of said vertical plane, a reversing arm mounted to said deflector shaft at the inner end thereof and movable to shift the position of said deflector, adjustable speed control means to limit the movement of said reversing arm to between first and second positions at which the volume of'water in said one jet component is alternately greater and lesser than the volume in said other jet component, and a pair of stop arms mounted on said journal boss and operably associated with said reversing arm to shift the same between said first and second positions.

3. An automatic water sprinkler head, which cornprises a stationary base having an upwardly extending journal boss, an axis tube journaled in said boss, a nozzlcmounted on the upper portion of said axis tube and extending in a generally horizontal direction, said nozzle having a Water passage communicating at its inner end with said axis tube and terminating at its outer end in a relatively large discharge opening, a deflector shaft journaled on said nozzle and generally parallel thereto, a deflector mounted to the deflector shaft at the outer end thereof and disposed adjacent said discharge opening, said deflector having angularly disposed deflector faces adapted to divide the water jet from said discharge opening into two components one of which is deflected to one side of a vertical plane containing the axis of said jet and the other of which is deflected to the other side of said vertical plane, a reversing arm mounted to the deflector shaft at the inner end thereof and movable to shift the position of said deflector, a lug on said reversing arm, adjustable speed control means to limit the movement of said reversing arm to between first and second positions at which the volume of water in said one jet component is alternately greater and lesser than the volume in said other jet component, a yoke pivotally mounted on said nozzle and operably associated with said reversing arm, a pair of ears on said yoke spaced on opposi e sides of said lug on the reversing arm for alternate engagement therewith, and a pair of adjustable stops mounted on said journal boss and operably associated with said yoke, an arm on said yoke so disposed and arranged as to alternately engage said adjustable stops, each of said stops operating through said yoke to 'eifectmovem'ent of said reversing arm between said first and second positions, and an overcenter spring connected to said nozzle, said overcenter spring being adapted to maintain said yoke in an extreme position relative to said nozzle until engagement of said yoke arm with one of said adjustable stops.

4. An automatic water sprinkler head, which comprises a stationary base having an upwardly extending journal boss, an axis tube journaled in said boss, a nozzle mounted on the upper portion of said axis tube and ex tending in a generally horizontal direction, said nozzle having a Water passage communicating at its inner end with said axis tube and terminating at its outer end in a relatively large discharge opening, a deflector shaft journaled on said nozzle and generally parallel thereto, a deflector mounted to the deflector shaft at the outer end thereof and disposed adjacent said discharge opening, said deflector having angulariy disposed deflector faces adapted to divide the water jet from said discharge opening into two components one of which is deflected to one side of a vertical plane containing the axis of said jet and the other of which is deflected to the other side of said vertical plane, longitudinal deflector faces on said deflector which lie in a plane parallel to and slightly above said jet axis, and grooves lying respectively along said angularly disposed deflector faces and at their junctions with said longitudinal deflector faces, said grooves and longitudinal deflector faces serving to improve the distribution of water in the upper portion of said jet, a reversing arm mounted to the deflector shaft at the inner end thereof and movable to shift the position of said deflector, adjustable speed control means to limit the movement of said reversing arm. to between first and second positions at which the volume of water in said one jet component is alternately greater and lesser than the volume in said other jet component, a yoke pivotally mounted on said nozzle and operably associated with said reversing arm, and a pair of adjustable stops mounted on said journal boss and operably associated with'said yoke, each of said stops operating through said yoke to effect movement of said reversing arm between said first and second positions.

An automatic water sprinkler head, which comprises a stationary base having an upwardly extending journal boss, an axis tube journaled in said boss, a nozzle mounted on the upper portion of said axis tube and extending in a generally horizontal direction, said nozzle having a water passage communicating at its inner end with said axis tube and terminating at its outer end in a relatively large discharge opening, a deflector shaft journaled on said nozzle and generally parallel thereto, a deflector mounted to the deflector shaft at the outer end thereof and disposed adjacent said discharge opening, said deflector having angularly disposed deflector faces adapted to divide the water jet from said discharge opening into two components one of which is deflected to one side of a vertical plane containing the axis of said jet and the other of which is deflected to the other side of said vertical plane, a reversing arm mounted to the deflector shaft at the inner end thereof and movable to shift the position of said deflector, said reversing arm having a hole therein, adjustable speed control means to limit the movement of said reversing arm to between first and second positions at which the volume of Water in said one jet component is alternately greater and lesser than the volume in said other jet component, said speed control means comprising a screw having a tapered end, said screw being threadedly mounted to the nozzle so as to be shiftable in and out of the hole in the reversing arm whereby the movement of the reversing arm transverse to the screw is progressively restricted by the progressive insertion of the tapered end of the screw into the hole in the reversing arm,'thereby adjusting theextreme positions of the deflector to determine the relative volumes in the jet components, a yoke pivotally mounted on said nozzle and operably associated with said reversing arm,

tions.

References Cited in the file of this patent UNITED STATES PATENTS Barnes Apr. 22, 1924 10 Schneider May 14, 1929 Buckner June 23, 1931 10 Norland Mar. 13, 1934 Buckner Mar. 28, 1944 Dunham June 3, 1947 Phillips June 3, 1952 Sciuto Apr. 6, 1954 Campbell Oct. 12, 1954 FOREIGN PATENTS Switzerland Jan. 3, 1945 Germany Oct. 31, 1933

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