US3465703A - Double-seaming method and apparatus for can closing machine - Google Patents

Description

Sept. 9, 1969 c. JANTZE ETAL 3,465,703

DOUBLE-SEAMING METHOD AND APPARATUS FOR CAN CLOSING MACHINE Filed QCt. 31, 1967 3 Sheets-Sheet 1 IN VENTORS CLYDE Ev JANTZE EDWARD A. ARNOTT RL V COTT BY l Sept. 9, 1969 Q JANTZE ETAL 3,465,703

DOUBLE-SEAMING METHOD AND APPARATUS FOR CAN CLOSING MACHINE 5 Sheets-Sheet 2 Filed Oct. 31, 1967 NW 140x) C) if N l T A X E P 0 T. T Y w ww T R N m v EA N I DR RA 7 C E W Y B CAM ANGLE OR TIME OPERATION Sept. 9, 1969 Q JANTZE ETAL 3,465,703

DOUBLE-SEAMING METHOD AND APPARATUS FOR CAN CLOSING MACHINE Filed 001,. 31, 1967 5 Sheets-Sheet 5 INVENTORS CLYDE E. JANTZE EDWARD A. ARNOTT EARL V SCOTT United States Patent US. Cl. 113-30 12 Claims ABSTRACT OF THE DISCLOSURE Arrangement and sequencing of seaming rolls for a high-production can closing machine with double-seaming operation. The machine is of the turret type with a number of seaming stations spaced around the turret, sets of closely spaced seaming rolls rotating with the seaming chucks as the turret revolves. A stationary cam ring controls pivoting of the rolls to and from the chucks. Second operation rolls describe paths which intersect the paths of first operation rolls in adjacent stations. The roll travel is so programmed that the second operation roll follows the first operation roll of adjacent station through the zone of potential interference, then advances to seaming position, whereafter the contiguous first operation roll retrat ts through the interference zone in advance of the retracting second operation roll.

BACKGROUND OF THE INVENTION Field of the invention This invention relates to a multi-station can closing machine of the roll double-seaming type, wherein first and second operation rolls at each station of the seaming turret rotate therewith while successively and repetitively performing a work cycle to complete double seams on cans carried by seaming chucks on the turret, stationary cam rings actuating the rolls. A machine of such general type is fully described in US. Patent 2,255,707, issued Sept. 9, 1941 to Alfred L. Kronquest and Otto A. Schmidt.

-In a preferred form of the general type, filled can bodies are received in turret pockets and there held with their ends by suitable seaming chucks. Each roll is carried on a pivotal shank arm for swinging the roll to and from the chuck, a follower on another arm of the shank travelling the suitably profiled track of a cam ring. This arrangement is particularly advantageous in that leverage is provided to establish required seaming force, seaming force and elevation adjustments can be readily made, and changeover is facilitated for accommodation of different can diameters within a predetermined range.

The prior art Rotary machines of the general type described are well suited to high production rates. However, practical considerations have limited production rates of prior closing machines to values considerably below the capabilities of associated filling machines now available on the market. A major problem not heretofore satisfactorily resolved has been the synchronization of the closing machine rate with the filling machine rate for continuousline, fully automatic production. Ideally, the cans should move through the filling and closing operations with the closest spacing and highest linear velocity which handling of the open-top filled cans will permit. Thus, the linear or tangential velocity of the closing machine turret and its station spacing should be as nearly as possible the same as those of the filling machine. Absent such correspondence of velocity and spacing, it becomes necessary to accelerate or decelerate the cans moving from the p ice filling machine to the closing machine. Such can velocity change, instituted at transfer stations, aggravates attendant jostling, increases spillage hazard, and however deftly achieved, causes sloshing due to inertial effect. As a consequence, only very low acceleration rates can be tolerated. In practice it has generally been found necessary to introduce additional transfers in the conveyor line solely for the purpose of minimizing acceleration rate, but thereby magnifying the jostling hazard.

It has been found that there is a rather critical relationship between roll diameter and can diameter for most effective seaming, whereby the acceptable roll diameter for each case is substantially predetermined. The roll diameter, in combination with other mechanical limitations, such as requisite leverage, mounting structure and the like, are the principal factors determining the minimum station spacing, diameter of the turret and number of stations thereon. With prior closing machine designs of the type here considered, for example as applied to closing popular beverage can sizes, the minimum station spacing achievable has been somewhat greater than that obtaining in modern high production filling machines. Therefore, substantial can acceleration is usually required between the filling machine and the closing machine seaming turret. Accordingly, the maximum can velocity is appreciably below that which could be achieved but for the jostling and spillage hazards attendant upon transfer and acceleration incidence.

Summary of the invention intersecting paths without interference.

It is a still further object of this invention to provide in a rotary closing machine for so arranging and manipulating double-seaming rolls that the effective seaming travel is a maximal portion of the can travel through the machine, whereby to improve seam quality, increase production rate, or both.

The foregoing and other objects and advantages of this invention will be apparent from the ensuing description read in conjunction with the accompanying drawings.

Description of the drawings FIG. 1 is a partly schematic, fragmentary elevation of a closing machine constructed in accordance with the invention, showing two seaming stations thereof, one of the seaming shank housings being shown in section and certain portions being broken away more clearly to dis close the structure and arrangement;

FIG. 2 is a partial bottom plan view of the stations, taken on line 2-2 of FIG. 1, showing the positioning of rolls and chucks;

FIG. 3 is a partial top plan view taken on line 33 of FIG. 1, showing the cam and follower arrangement, associated with the seaming stations of FIGS. 1 and 2;

FIG. 4 is a diagrammatic plan of the roll and chuck positions in a closing machine as arranged prior to this invention;

FIG. 5 is a diagrammatic plan similar to FIG. 4, show ing rolls and chucks arranged according to this invention;

FIG. 6 is a motion/time diagram of a roll operation program according to prior practice, as applied to the arrangement of FIG. 5;

FIG. 7 is a motion/ time diagram similar to FIG. 6, but of roll operation program according to this invention; and

FIG. 8 is a cam profile diagram corresponding to the operation diagram of FIG. 6.

Preferred embodiment Referring to FIGS. 1-3, turret 10 is carried on shaft 11 for rotation by means of suitable drive mechanism (not shown), such drives being well known in the art and not forming part of this invention. A variable speed drive is ordinarily employed to provide for synchronizing the operation of the closing machine with the rate of delivery of cans from a filling machine.

As best seen in FIG. 2, several seaming chucks 12 are equally spaced around the turret, two such chucks being shown. The chucks, in cooperation with presser-foot plates (not shown), serve to hold and drive can bodies and ends for the seaming operations, the chucks being rotatable about their own axes as they revolve with the turret 10, in a manner well known in the art. The two chucks 12 constitute two seaming stations with two pairs of rolls, a first operation roll 13 and a second operation roll 14 at each station.

Each roll is freely rotatable upon its shaft 15 carried on arms 16, 17 extending from seaming shanks or spindles 18, 19 which, as best seen in FIG. 1, are journalled in the spindle housings 20, 21 affixed to the turret 10.

Referring particularly to FIGS. 1 and 3, the upper ends of spindles 18, 19 carry arms 22, 23 on the outer ends of which are followers 24, rotatable upon shafts 25 mounted at the ends of arms 22, 23. Follower arms 22, 23 are positioned to present followers 24 to cam tracks 26, 27 on the cam ring 28, the followers being held in contact with the tracks by means of springs 29, 30 bearing on housing pads 31, 32 and against arm lugs 33, 34. Upper cam track 26 controls the first operation rolls 13 and lower cam track 27 controls the second operation rolls 14. Cam ring 28 is fixed to the shaft housing, whereby, as the turret revolves, followers 24 travel the respective tracks, the profiles of which are patterned to establish the desired sequencing and progress of the seaming operations, as the chucks 12 and rolls 13, 14 revolve with the turret. When followers 24 ride on depressed or base portions of the cam profile, the rolls are in retracted positions, away from their respective chucks, and as the followers travel rises in the cam profiles, their respective shanks 18, 19 pivot the rolls carried thereby toward the chucks 12. With the followers traveling the highest rises of the profiles the respective rolls 13, 14 are held in predetermined seaming positions relative to their respective chucks 12 for times determined by the arcuate lengths of the rises and the angular speed of the turret 10.

As will be seen particularly in FIG. 2, the several roll and shank assemblies are closely grouped around the periphery of the turret. In locating the seaming shanks 18, 19, consideration must not only be given to accommodation of roll sizes best suited to seaming cans of given diameter, sufficient leverage to minimize pressure and stresses on cam tracks and followers, and other such operational factors, but also to the matters of maintenance, adjustment, roll replacement, and the like. These factors, together with desirability of maintaining the entire turret assemblage generally as compact as possible, impose limitations on the location and dimensioning of the seaming shank assemblies and constitute major factors in determining the minimum practicable station spacing on the turret.

Reasons of practical construction and arrangement dictate' that the seaming shank housings 20, 21 for a given station be arranged to bring seaming shanks 18, 19 in as close to the chuck 12 as possible, a grouping which is best accomplished by so positioning the parts that one set of rolls nests between chucks. As shown in FIG. 2,

the second operation rolls 14 are so nested. This disposition of the seaming shanks and rolls, while advantageous for the reasons aforesaid, results in orientations whereby the paths described by second operation rolls 14 and first operation rolls 13 in adjacent stations, when pivoted about their respective shanks, converge between retracted and seaming positions. Since all the rolls are necessarily very nearly in the same plane of elevation, as seen in FIG. 1, particular care must be taken in the spacing of stations to see that the second operation rolls 14 swing clear of first operation rolls 13 in adjacent stations. Inasmuch as a given closing machine should be adaptable to a reasonable range of can diameters, variations in materials and other variables affecting the seaming operation, some of which may involve changing rolls, or varying the roll sequence timing and duration of the seaming cycle, it is necessary to assure that roll interference is avoided for all possible setups, adjustments and changes in operation of the machine within the range of variables for which the machine is intended.

In prior designs of the general type involved, interference has been obviated by so designing that the most nearly opposing peripheral points of adjacent rolls on converging paths clear at all possible positions along those paths, as illustrated in broken lines, FIG. 4, indicating the paths of points T(l) and T(2) on second and first operation rolls for stations 8(1) and 8(2) respectively. A minimal roll diameter having been established by considerations of optimal seaming quality, and other clearances having been reduced to their practical minima in consideration of arrangement around chucks of predetermined diameter, the' minimum clearance C between rolls R( 1) and R(2) becomes the ultimate determinant of the minimum feasible station spacing, indicated as angle A, for any given chuck circle diameter D. In this determination, possible use of somewhat larger rolls must be given consideration, constituting another increment of clearance C and further increasing the minimum nermissible station spacin FIG. 5 shows chuck spacing and roll placement according to this invention, the view representing diagrammatically the turret sector of FIGS. 1-3 as seen from the top view of FIG. 3. It will be seen that second operation roll 14(1) of station 12(1) has a peripheral point P(l) travelling an arcuate path which intersects the path travelled by an opposing peripheral point P(2) on the first operation roll 13(2) at station 12(2), adjacent to station 12(1). The lapping portions of rolls 14(1) and 13(2) define the interference zone Z1, indicated by the shaded area. Manifestly, for given roll diameter the arrangement of FIG. 5 permits substantially closer station spacing than the arrangement of prior designs exemplified in FIG. 4. However, the arrangement of FIG. 5 cannot be used with seaming operations performed according to past practice, as illustrated by FIG. 6.

In the operation diagram, FIG. 6, the abscissa represents angle of revolution relative to the cam. Since the turret is rotating at constant speed the abscissa is also a time scale. The ordinate is scaled as a function of the radial traverse, or rise and fall, of a cam follower 24, FIG. 3, to which the travels of rolls 13, 14, to and from the work, are proportionate.

Trace 13(1X) represents the travel of the first operation roll 13(1) at station 12(1), FIG. 5. Trace 14(1X) represents the travel of the second operation roll 14( 1) at station 12( 1). Trace 13(2X) represents the travel of the first operation roll at station 12(2), lagging station 12(1) by a time which is a function of the station spacing. Traces 13(1X) and 13(2X) have the same profile as determined by the first operation cam track 26, FIG. 1. Path a-b represents an inward rapid traverse of first operation roll 13(1), b-c a seam forming traverse, c-d a finish traverse and 61-2 a rapid retract traverse. f-gh-ij represents the same program for first operation roll 13(2) at station 2. k-lmno represents a similar, but non-homologous program for second operation roll 14(1), the ordinate for lm being less than for b-c, since the second seaming operation involves a shorter radial working travel than the first operation, according to best double-seaming practice. The second operation seaming pass begins at point 1 substantially as the first operation work finishes at point d, to minimize effect of springback in the seam and to provide maximum possible working time during the complete cycle represented along the abscissa by a-o. Such continuity of operation is a desirable, even necessary, characteristic of the doubleseaming operation program.

The shaded area Z(X) along path kl, is diagrammatically representative of the correspondingly shaded interference zone ZI, FIG. 5, the geometric nature of which is there shown. For the purposes of illustration here it is sufficient to note the crossing of area Z(X) by the traverse line g-h, delineating actual interference between roll 13(2) and roll 14(1) under the program shown. Reproportioning the first and second operation motion cycles within limits acceptable for the work to be performed cannot avoid the roll interference, within the confines of roll operation programs heretofore known, which are of the character represented in FIG. 6. The rises between f and g and between k and l are predetermined within very narrow limits by the nature of the operation. The second operation pickup at point 1 cannot be significantly retarded in relation to the first operation finish at d, if at all, without adversely affecting the quality of the seam, even assuming acceptable shortening of the second operation work cycle or lengthening of the full cycle. Stated generally, the close station spacing of FIG. 5 cannot be adopted with any previously known operating program such as that of FIG. 6, wherein the second operation roll makes a rapid traverse advance k-l from retracted position to work position, within practical limits of variation, because of unavoidable interference between rolls 14(1) and 13(2).

FIG. 7 illustrates the novel operation program whereby the close station spacing of FIG. 5 is practicably achieved. In FIG. 7 the first operation traverses are indicated by traces 13(1Y) and 13(2Y), the second operation traverse being indicated by trace 14(1Y). Profiles 13(1Y) and 13(2Y) are similar in shape and dimension to the corresponding profiles 13(1X) and 13(2X), FIG. 6, except for greater overall length and consequent lesser slope along lines bbcc and gg-hh. The latter characteristic is feasible and advantageous with the program of FIG. 7 for reasons subsequently shown.

The second operation trace 14(1Y) coincides with 13(1Y) along a short rapid inward traverse along aa-aa', from which latter point there is a gradual inward traverse to point kk along a line parallelling gg-hh, then a second rapid inward traverse to point 11, whereafter the profile is substantially the same as that of 14(1X), FIG. 6. The shaded area Z(Y) indicates the interference zone along the traverse aa'kk of the second operation roll 14( 1) corresponding to Z(X) along k-l, FIG. 6.

The cycle of the first operation roll 13(2) in station 12(2), FIG. 5, is represented by trace 13(2Y). A horizontal line through zone Z(Y) intersects trace 13(2Y) at Z(l) on operating path gg-hh and at Z(2) on retract path ii-jj, the same line intersecting second operation trace 14(1Y) at Z(3) in its retract path nn-oo. The substantial horizontal distances between the several intersects represent substantial differences in times at which the rolls pass through the zone Z(Y). That is, roll 13(2) leads roll 14(1) through zone Z(Y) on the respective advances and retracts, both rolls occupying seaming positions for overlapping periods of time while beyond the zone of potential interference. Since aakk parallels gg-hh to a point beyond zone Z(Y), the advance travel aa'kk of roll 14(1) may be shifted forward in time any amount just less than the time represented by Z(1)Z(Y),

should a shorter first operation be acceptable in a particular case, and similarly as to the retract timing between points Z(2) and Z(3) on ii-jj and nn-oo respectively, for a shorter second operation cycle. That is, the timing of the operations can be varied and normal adjustments in the seaming cycles can be made by means of the expedients usually resorted to for those purposes, without changing the roll diameters, seaming shank locations, station spacing, or other major restructuring of the station assemblage.

A typical cam profile for operation according to the program of FIG. 7 is shown in FIG. 8. The cam ring 28 is here shown diagrammatically, with the profiles exaggerated radially for the sake of clarity, and the second operation profile rotated through an angle and in the direction to coincide in actuation time with the first operation profile, that is, advanced through the angle between first and second operation followers for rolls of given station. The first operation profile of track 26, FIG. 1, is shown by the solid line and second operation profile of track 27 by the broken line. The dash line B represents the continuation of the base reference profile or zero rise line corresponding to fully retracted positions of the rolls. The points indicated by letter reference characters correspond to the points so indicated in FIG. 7.

In addition to the advantages of lower lineal can speed for a given production rate, or higher production rate with given lineal speed, other important practical advantages obtained from the close station spacing provided by the arrangement shown in FIGS. 2 and 5, with programming according to the principles and illustrative example shown in FIG. 7. For purpose of illustration, it is assumed that the chuck circle diameter D, FIG. 4 is predetermined and equal to D, FIG. 5. In actual practice the chuck circle diameter is predetermined within rather narrow limits for a machine to be used in association with a filling machine of given design, by such factors as can intake and delivery, accommodation of drives and other appurenances, and similar factors. In this example it is found that seaming shank and roll clearance requirements for the arrangement of FIG. 4 dictate a minimum spindle spacing S(1)-S(2) on the order of 4 /2. Such minimum spacing corresponds to a minimum angular spacing A of 36, by closest even division of the circle having a diameter D. That is, the turret will have 10 stations with spindles spaced at 4 /2". A representative high production filling machine has about 3% station spacing, so that about 30 percent acceleration will be required between the filling machine and the closing machine, involving several transfers, costly additional conveying and transfer equipment for can line acceleration, and attendant aggravated spillage hazard. Due to space required for can intake and discharge stations, idle turret return, and time for rotary can acceleration, gassing, and the like, the total seaming time for the assumed 10 station machine is limited to about 200 of the turret revolution. With the seaming chuck turning on its spindle at a maximum speed compatible with limits of rotary acceleration at intake and sloshing before closing, the can makes about 10 turns maximumduring the seaming operation, divided about equally between first and second operations, as indicated by N(IX) and N(2X) in the program of FIG. 6, being close to, or even less than, the minima for acceptable seaming quality with many of the usual can materials.

Referring now to FIGS. 2, 5 and 7, a machine so arranged and programmed, according to this invention, can be constructed for 3%" spacing 12(1)-12(2) on assumed chuck circle diameter D, that is, A'=30 and there are 12. stations. With the chuck spindle spacing only slightly greater than the 3%" predetermined filling station spacing, a single acceleration transfer will suffice, obviating extra transfers and conveyor apparatus and appreciably minimizing spillage hazards, whereby the entire operation can be safely speeded up, if desired,

for higher production rate than otherwise attainable. Futhermore, the closer station spacing may be utilized to effect conservations in space requirements, particularly at intake and discharge, whereby the seaming cycle may be extended about 15% beyond that heretofore attainable, to about 230 of turret rotation, or about 11 /2 can turns with acceptable chuck spindle speed. This longer seaming cycle may be distributed between first and second operations in such a manner as represented by FIG. 7, with N(1Y) representing about 7% turns in the first operation and N(2Y) about 4% turns in the second. Such programming is highly desirable for best seaming quality with high temper can materials, a quality not obtainable with prior closing machines, except with substantial sacrifice in production rate. On the other hand, for the closing of cans not requiring a long seaming cycle for acceptable quality, the closer station spacing may be advantageously utilized with higher linear can line velocity, thereby achieving higher production rates than heretofore attainable. Various combinations of linear can velocity and seaming cycle timing can be established for particular production requirements by the relatively simple and readily accommodated expedients of cam interchanges and appropriate turret speed regulation.

It will be apparent that the closer station spacing and novel roll operation programming of this invention greatly facilitate adaptation of a given basic machine to a variety of production requirements, as well as providing higher production rates, with minimum changes of parts or structures, as compared to machines heretofore known or used. Since provisions for changes or adjustments of the general character indicated are usually required in any event, the additional facility and range are achieved without increase in basic machine costs; on the contrary, considerable savings can be made in conveyors and appurtenant equipment, which together with the potentials in improved product quality and higher production rates comprise a substantial economy in the entire filling and closing operation.

Those skilled in the art will be enabled by the foregoing description to devise variations and modifications of the invention without departing from the spirit and scope of the invention as defined by the claims. For example, a number of variations in turret structures may be made with respect to spindle circle diameter, number of stations, roll diameters, and the like to suit various requirements in can sizes, materials, operating space limitations, filling and conveying equipment and the like, the facility for which is greatly enhanced by use of this invention.

It will be understood that specific representations of station arrangement, structure and operation are by way of example or illustration only. Such terms as first operation and second operation are used only for purposes of identification in the illustrations and examples used to describe those structures, arrangements, motions and other features which the invention comprises.

The invention is limited only by the claims, which are as follows:

1. A method of double-seaming cans in close succession at closely spaced seaming stations with a succession of closely spaced rolls, which comprises the steps of:

(a) advancing a first-station first roll from a retracted position to a seaming position;

(b) advancing a first-station second roll from a retracted position to an initial intermediate position during the initial advance of said first-station first roll;

(c) advancing a second-station first roll from a retracted position to a seaming position while said first-station second roll advances through intermediate positions;

(d) advancing said first-station second roll from an intermediate position to seaming position while said second-station first roll is in seaming position;

(e) successively retracting each said roll; each said roll performing a seaming operation while in seaming position; and performing said steps successively at said second station and at successive stations.

2. A method according to claim 1, wherein said second-station first roll is retracted before retracting said second roll.

3. A method according to claim 1, wherein each said first roll advances from an initial seaming position to a finish position at a predetermined travel rate and said second roll advances through a range of intermediate positions at substantially said predetermined rate.

4. A method according to claim 1, wherein the advance of said second roll comprises an initial short rapid traverse, then a slow traverse to a position close to seaming position, followed by a rapid traverse to said seaming position.

5. A method acording to claim 1, wherein each said first roll performs a like first seaming operation at a separate one of immediately successive stations, said second roll performing a second seaming operation at the first of said stations, said second roll travelling a path between the paths of said first rolls.

6. A method acocrding to claim 5, wherein each said first roll advances from a retracted position to an initial seaming position by rapid traverses along nearly parallel paths of the same predetermined length, said second-roll path from its said retracted position to its said initial intermediate position being substantially shorter than said predetermined length.

7. Apparatus for successively double-seaming a series of cans, comprising: a closely spaced series of seaming chucks adapted to position a series of cans and respective ends thereof for seaming operations thereon, a series of closely spaced seaming rolls associated with said chucks, each of said rolls being movable from a retracted position to a seaming position relative to one of said chucks, certain ones of said rolls being so movable along interfering paths, and cam means actuatingly associated with said rolls, said rolls and said cam means being relatively translatable to determine the timing and sequencing of roll movements relative to said chucks, the characteristics of said cam means being so predetermined that said certain rolls travel said interfering paths at rates and in sequence to avoid interference thereof as said rolls move to and from said seaming positions.

8. Apparatus according to claim 7, wherein said chucks and said rolls are arranged in stations upon a turret, each said station comprising a chuck with a first roll and a second roll associated therewith for pivotal movement relative thereto, said cam means being generally ringshaped, said turret being rotatable relative to said cam means, followers associated with said rolls travelling tracks on said cam means to establish said roll travel rates and sequence as said turret rotates relative to said cam means.

9. Apparatus according to claim 8, wherein said chucks are arranged in a circle, said rolls being carried on pivot arms the pivotal centers whereof are arranged on circles concentric with said chuck circle, said rolls comprising a series of alternating first and second rolls, said certain rolls being adjacent first and second rolls.

10. Apparatus according to claim 8, wherein said rolls comprise first and second rolls at each said station, said rolls being carried on pivot arms, said arms in normal operating positions extending from their respective pivot centers generally in the same direction relative to the direction of turret rotation, with a second-roll arm at one said station extending generally toward a first roll at a next succeeding one of said stations, said pivot centers and radii of said arms being so related that the path described by a portion of said second roll at said one station in travel between retracted and seaming positions intersects an opposed portion of said first roll at said succeeding station in travel between its retracted and seaming position through an interference zone between retracted and terminal seaming positions along both said paths, said cam means characteristics being such that each said roll portion occupies said interference zone at a difierent time during a period when both said certain rolls are actuated in respective seaming operations by said cam means.

11. Apparatus according to claim 10, further characterized in that a first track of said cam means actuates said certain first roll along its seaming traverse at predetermined rate while a second track of said cam means actuates said certain second roll along a traverse intermediate of its retracted and seaming positions at substantially said predetermined rate, said second-roll portion traversing said interference Zone at said rate subsequent to the time at which said first-roll portion traverses said zone.

12. Apparatus according to claim 11, still further characterized in that said first track actuates said certain first References Cited UNITED STATES PATENTS 12/1940 Kronquest 53-272 8/1948 Nordquist 53-334 RONALD D. GREFE, Primary Examiner US. 01. X.R. 113 1, 121

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