US 3207409 A
Abstract available in
Claims available in
Description (OCR text may contain errors)
Sept. 2l, 1965 R. F. REIFER ETAL MOLDED PULP EGG- CARTON Filed Sept. 4, 1962 5 Sheets-Sheet l INV ENTORS Ric/mrd /Pe/'fers Henry A. 0rd
ATTORNEY Sept 21, 1965 R. F. REIFERS;V ETAL 3,207,409
MOLDED PULP EGG CARTON Filed sept. 4, 1962 l 5 sheets-sheet 2 INVENTORS Richard He/Yers Henry A. Lord Kaal. L0 :Flocczs -wmmy sept. 21, 196s R. F. REWE@ UAL 3,207,409
MOLDED PULP EGG CARTON 5 Sheets-Sheet 3 Filed Sept. 4, 1962 INVENTORS R/'c/mrd Re/'fers Henry A. 0rd
1 ATTORNEY Kam. (L). :Fleau-S Sept. 21, 1965 R. F. REIFER ETAL 3,207,409
MOLDED PULP EGG CARTON 5 Sheets-Sheet 4 Filed Sept. 4, 1962 Rigid Flexible Aren INVENTORS Hic/lard He/'fers Henry A. 0rd
KARL CL). :FLocus ATTORNEY Sept. 2l, 1965 R. F. REIFERSETAL 3,207,409
MOLDED PULP EGG' CARTON Filed Sept. 4, 1962 5 Sheets-Sheet 5 INVENTORS Hic/mrd E Reife/s Henry A. Lord BY Kam. M ),fFLocus ATTORNEY United States Patent O 3,207,409 MOLDED PULP EGG CARTON Richard F. Reiter-s, New Canaan, Conn., and Henry A.
Lord, Ialmer, Mass., assignors to Diamond International Corporation, a corporation of Delaware Filed Sept. 4, 1962, Ser. No. 221,028 Claims. (Cl. 229-25) The present invention relates generally to molded pulp articles, and more particularly to an improved molded pulp egg carton in which selected portions of the egg cells are provided with increased strength and improved cushioning characteristics.
Eggs are widely marketed throughout the world in cartons that hold la dozen eggs each, and among the most widely known type of egg carton, is one that is produced trom molded pulp. Molded pulp egg cartons are produced on pulp molding machinery in a conventional manner, wherein the carton is deposited by suction imposed .within a die of desire-d coniiguration and a slurry of pulp is deposited on the exterior of the die. Ilhereafter, in order rto enhance the appearance of the carton as well as to substantially soften the material from which the carton is produced, the article is pressed between mating dies.
In these known egg cartons, the eggs are held in egg cells, separated from each .other by `saddle portions between adjacent cells and verticals posts lhaving four cell-s Aformed .thereabout The eggs are generally in contact with the walls of the cells .and thus shocks to the exterior of the carton result in force being transmitted to the eggs through the walls of the carton, accordingly resulting in the small amount of egg breakage that presently exists.
Additionally, in known molded egg cartons, there is some egg movement or egg rattle, and this .rattling of the eggs within the carton as they are shipped or the carton is handled, has in part contributed to egg breakage. Further, the so-called rattling of the eggs has resulted in a deleterious effect on the quality of the eggs.
Further, in prior art egg cartons, it has .been the general practice of packaging eggs of a given size or quality together in one carton, and in order to provide the best possible marketing of eggs, consistent with necessary economies, it has been the general practice to provide different sizes of cartons for some of the different grades of eggs. Despite the care that has been taken in `sorting the eggs, unless the selection is carried to a degree far beyond that which is economical-ly feasible, a dozen eggs of a particular grade, as far as marketing standards are concerned, will nevertheless vary, one from another, over a certain range of exterior dimensions as well as weight. Thus, as a result of the variations lof individual egg grades and weights, it Ihas been found that those eggs which depart from the standar-d of a particular gr-ade, will not be securely and properly retained in an egg cell.
Although molded pulp egg cartons may be produced to accommodate all sizes of eggs, however, to store and tool up to produce the range -of sizes of egg cartons necessary to accommodate all the single variations is neither practical nor economical. Additionally, the shipping cartons in which egg cartons are shipped and stored generally have uniform exterior dimensions, Yand therefore there has been a constant attempt to maintain exterior dimensions of the egg cartons relatively uniform. Further, there ha-s lbeen a constant research to develop a substantially universal carton which will accommodate and protect substantially all ranges of sizes of eggs without materially changing exterior dimensions of the carton, and it is toward this end which the novel carton and method of the present invention is directed.
The primary object of the present invention is to prolCe vide a novel substantially universal molded pulp egg cart-on in which egg movement and rattle are substantially reduced, to accommodate for varying dimensions of the eggs and reduce accidental .breakage to a minimum.
A further object of the present invention is to provide an egg carton which includes features which permit ready denesting or separation of a stack of egg cartons, one from the other.
A still further object of the present invention is to provide a molded pulp egg carton in which both large and small dimensioned eggs will be adequately supported, and the eggs will be supported in a relatively soft support surface on support structure to retain the-m in a re1- atively protected and xed position Within an egg cell and both relatively large and small sized eggs can be readily accommodated in the same carton.
Still another object of the invention is to provide a molded pulp egg carton which includes a cell structure having relatively rigid and reinforced outer walls to protect against external shock, and a relatively soft and resilient inner support surface for readily absorbing shock transmitted to the eggs from the outer wall.
And yet another object of the present invention is to utilize a novel reforming method vfor -molded pulp egg cell support structure whereby the nature of the egg support surface, due t-o the fiber character of the material used to produce t-he car-ton, is such that certain ber porti-ons are substantially softened and reoriented to a degree to aiford in a sense mechanical movement between integral and reoriented ber.
An-d a still further object -of the present invention is to provide, in a novel egg cell structure for -molded pulp carton portions, substantially tangential contact with eggs in the cell so that there is a minimum of sticking of the eggs in a cell due to leakers or broken eggs whereby eggs may be readily .removed yfrom the cel-ls.
And yet another object of the present invention is to prov-ide a novel cell structure in molded pulp egg cartons of a capacity different from the conventional onedozen egg capacity.
Still another object of the present invention is to provide a novel carton of the char-acter involved which includes a novel lid end wall support and ventilation structure which aifords ithe necessary strength, rigidity and load transmittal characteristics for cartons of the character involved.
Other objects and the nature and advantages of the instant invention will be apparent from the following description taken in conjunction with the accompanying drawings, wherein:
FIG. l is a top plan view of a molded pulp egg carton, incorporating the novel features of the invention;
FIG. 2 is a front elevation of the carton of FIG. 1, on a reduced scale, showing the carton in a closed condition;
FIG. 3 is a vertical section taken substantially on the plane of line 3-3 of FIG. 2;
FIG. 4 is a Vertical section taken substantially on the plane of line 4 4 of FIG. 1;
FIG. 5 is a fragmentary vertical section taken substantially on the plane of line 5 5 of FIG. 1;
FIG. 6 is a vertical section similar to FIG. 5, showing the appearance of a separator post after initial disposition of a pulp slurry on a suction mold die, and prior to pressing of the same;
FIG. 7 is a vertical section similar to FIGS. 5 and 6, showing the appearance of a separator post cushioning area during initial pressing;
FIG. 8 is a vertical section similar to FIGS. 5-7 showing the appearance of the cushioning area of a vertical separator post after reforming or secondary pressing thereof;
FIG. 9 is a vertical section similar to FIGS. 5-8, showing the residual position of the vertical separator post cushioning areas;
FIG. 10 is an enlarged fragmentary horizontal section taken substantially on the plane of line 10-10 of FIG. 6, showing a cross section -through one vertical post cushioning area after original molding or disposition of the pulp slurry on a suction mold forming die; and illustrating diagrammatically the random or normal orientation of the article fibers;
FIG. 11 is an enlarged horizontal section taken substantially on the plane of lines 1111 of FIG. 7, showing the initial forming step which generally is accompanied by considerable pressure and heat applied between mating pressing dies, and illustrating the manner in which the bers at the cushioning are reoriented, the inner surface bers being subject to greater tension than those in the outer surface of the cushioning area;
FIG. 12 is an enlarged horizontal section taken substantially on the plane of line 12-12 of FIG. 8, showing the manner in which the cushioning area is reformed between mating dies to subject the outer surface fibers to greater tension than those on the inner surface as mentioned with respect to FIG. 11
FIG. 13 is an enlarged horizontal section taken substantially on the plane of line 13-13 of FIG. 9, illustrating the manner in which the cushioning area tends to assume a substantially planar condition due to the memory effect caused by the step of FIG. 1l, shown by phantom lines, the cushioning area comprising super soft fibers on both the inner and outer surfaces of the cushioning area;
FIG. 14 is a perspective view of another embodiment of the novel carton in an open condition, incorporating the novel cells and including a modified lid end wall in conjunction with a slightly modified support post top wall;
FIG. 15 is an end vieW of the carton of FIG. 14 when closed, looking from left to right at FIG. 14; and
FIG. 16 is la fragmentary vertical section taken substantially on the plane of line 16--16 of FIG. 15.
Referring to the drawings in detail, a molded pulp egg carton is indicated generally at 1t) and comprises a lower bottom or egg receiving section 12, to which is hingedly connected at 14 a lock flap 16. Hingedly connected opposite the lock ap 16 as indicated at 18 is a substantially planar lid or cover member 20.
The cover member 20 includes a substantially planar top 22 integral with an outwardly angled or diverging peripheral side wall 24 which terminates in a peripheral lower bead 26. The front or forward wall 2S of the peripheral wall 24 has extending therethrough longitudinally spaced apertures or slots for receiving therethrough locking buttons 32 projecting forwardly from the lock flap 16, the rear appearance of these lock buttons being shown in FIG. 1.
The lower or egg receiving section 12 of the carton includes a plurality of substantially similar, egg receiving cells indicated generally at 34, each of the cells being separated one from the other by means of longitudinally and transversely extending saddle portions 36 and 38, respectively. Intersecting pairs of the saddle portions 36, 38 substantially define edge portions of frusto-pyramidal separator posts indicated generally at 40 which terminate in a substantially square top portion 42, the corners of which are disposed in alignment with the saddle portions 36 and 38. The upper portions 42 of the separator posts 40, as seen in FIG. 3, will abuttingly engage the inner surface of the planar top 22 of the cover member 20 for absorbing force on the cover member and transmitting it through the post to the bottom portions of the cells Without injury to the eggs contained therein.
The egg receiving section 12 includes a peripheral marginal edge portion 44, portions of which engage the peripheral bead 26 of the cover member when the carton is closed in the manner shown in FIG. 2. The posts are eliminated at portions 46 at the opposite ends of the carton; however, the egg supporting structure in the endmost cells functions in substantially the same manner as that of the innermost cells. Each of the cells 34 comprises a transverse bottom 48 preferably including a cushioning button 50. The cells, when Viewing the interior thereof, as seen in FIG. 1, are formed with upwardly and outwardly integrally connected adjacent cell forming sections, or segments 52 and 54, which converge upwardly and terminate at the upper surface of the saddle 38. Adjacent segments 56 and 58 converge upwardly and terminate at the longitudinally extending saddles 36. Segments 60 extend outwardly and terminate at the hinge line 14 and constitute a portion of the forward wall of the egg receiving section of the carton, and segments 62 extend upwardly and outwardly and from a portion of the rear wall of the egg receiving section.
The segments 52, 54, 56 and 62 are generally not engaged by an egg disposed in the cells unless than eggs are particularly large or of a golf-ball shape, for example. Each of the cells affords a substantial four-point support for the eggs disposed therein. This four-point suspension of the eggs is afforded by a pair of similar cell forming segments 64 and 66 which have a lower portion having a convex cross section, when viewing the interior of the cells, this convex cross section merging into vertically extending and elliptical or tear-Shaped pressed areas 68 and '70, respectively. If preferred, the elliptically shaped sections 68 and '76 may have vertically extending therein inwardly pressed rib portions 72 and 74 respectively, which in effect reduce the surface exposure to the eggs in the `cells to prevent sticking of eggs in the case of a leakerj for example.
The segments 62, 64 and 66 provide a relatively rigid wall in the cells, however, the pressed areas 63 and 7i) are relatively sof and together with the ribs 72 provide a minimum of egg contact. The convex surface may have an arc which is shallower than that found in most eggs, and thus minimum egg Contact is insured. This relatively rigid outer Wall construction for the cells aifords protection of the eggs due to lateral shock occurring during handling, packing and shipping.
The frusto-pyramidal separator posts 4@ include substantially planar post forming segments 76 and 78 in the respective cells 34, and four adjacent cells including opposed pairs of segments 76 and 78, as clearly seen in FIG. 1, which -together with the top portion 42 form one of the frusto-pyramidal separator posts. It will be noted thay the opposed pairs of post forming segments 76 and 78 converge into the substantially rectangular or square upper end portion 42 of the separator post. The cell segments 62 extend in planar relation down to the cell bottoms and are disposed at a greater angle with respect to the vertical than the adjacent convex segments 64 and 66. Stated in another way, the segments 64 and 66 are more vertically disposed than the segments 62. The pressed areas 68 and 70 are formed above the base of the cells and extend upwardly and outwardly at a still greater angle.
The cushioning areas or bubble indents 80 are formed above the -base of the cells and are arcuate along their length, rst curving inwardly a greater degree than the shallow return curve as seen in FIG. 7. The shallow return curve aids to control egg rattle in the upper zone of the egg cells.
The adjacent cell Walls 76 and 7S are set off from each other at approximately 45 degrees with respect to a vertical plane passing through the saddle 36 therebetween, and the flutes or areas 68 and 70 are at approximately 32 degrees with respect to this vertical plane.
This arrangement provides maximum base footing for the carton when closed to transmit vertical loads on the closed carton. Further, good nesting is obtained with this arrangement. All of the egg bearing surfaces 64, 66, 76 and 7S of a cell extend upwardly and outwardly from the cell base at substantially 121/2 degrees at a lesser angle than adjacent non-egg bearing segments. The c ushioning areas 68 and 70 extend at an angle of substantially 21 degrees7 and the egg cushioning areas 80 on the up posts comprise a compound arc along their length for controlling egg rattle as mentioned above.
Each of the separator post segments 76, 78 has formed therein vertically extending and substantially elliptically shaped egg contact or cu-shioning areas, the major axis of which extends above and below the upper edge margin 44 of the egg receiving section 12. The egg contact areas include therein a vertically extending and substantially thin strip of natural random formation fiber extending substantially the length thereof, and surrounded by a relatively thicker section of reoriented ber bordered by still thicker sections of reoriented fiber reinforcing the corners of the separator posts. The structure will be described in detail with respect to FIGS. 6-13.
Considering FIG. 6, a typical separator post is indicated at 40', this constituting substantially the configuration of the posts when they are initially deposited on a suction mold. Further, considering one of the wall portions 82, also see FIG. l0, there is formed in these Wall portions by means of a suitably conformed blanking element on the suction die, an elongated, relatively thin Strip 84 of natural random formation liber visible when looking into the posts; see FIG. 6.
After the initially molded carton or preform is removed from the -suction die screen, it is pressed between a pair of cooperating male and female dies into the condition 4shown in FIG. 7. The separator post indicated at 40, FIG. 7, and the wall 82 thereof is subjected to considerable pressures and/or heat which reorients the fibers into substantially parallel planes, this resulting in a softening of the separator post. The pressing dies are suitably formed to provide cushioning areas 86 extending around the fiber strips 84. Still further the pressing dies will form on the outer surface of the normally oriented fibers elongated ribs 88 which will provide substantially tangentlal contact with the outer surface of eggs supported in a ce The forming step illustrated in FIGS. 7 and 11, is for the purpose of not only softening the cushioning area 86, but also imposing in the separator post wall 82 an indented portion to normally accommodate the largest size egg of a particular range that will be packed in the cartons. The excessive curvature results in the bers of the inner surface of the wall 82 as indicated at 90, being subject to tension or in a sense pulled apart.
y Considering FIG. 8, the separator post is indicated at 42 and the cushioning area fiber 86' is reversely oriented 1n the direction opposite that :shown in FIG. 11, see FIG. 12. Flihe reverse pressing of reorientation that occurs due to sultably conformed dies to obtain the construction shown in FIG. 8, results in an outward bowing of the cushioning area now indicated at 86', and the cushioning area fiber indicated at 90 is .subject to a compression which tends to cause the fiber in this inner surface area to move together or slide with respect to adjacent fiber, and the vber at the outer surface of the cushioning area as indicated at 90 is now subject to tension similar to that described with respect to the portion at 90. The reverse reorientation results in the cushioning area assuming a substantially planar condition as indicated at 82 in FIGS. 9 and 13, the separator post walls 82 assuming this condition due to a substantial memory effect due to the configuration initially produced in the steps shown in FIG. 7 and FIG. 11. The cushioning area 86 of the separator post walls will have been super softened wherein the bers on the outer and inner surface will be in effect in interdigitated relationship to permit ready inward or outward movement. The planar condition of the post walls facilitates denesting.
Additionally, during the multiple pressing steps mentioned above, the corners of the separator post will receive the excessive material therein and become relatively rigid or thickened to substantially rigidify thepost for the purpose of transmitting vertical force on the carton lid. The ribs 88 of the separator post side walls will have substantially tangential contact with eggs supported in the cells, and lateral blows to the carton will be readily adsorbed by the super softened cushioning areas 86" when the separator post walls are disposed in the planar relationship as indicated at 82', in FIG. 13, or medium or large size eggs will be accommodated in the cells. However, in the event a packer decides to pack extra large or jumbo size eggs in the cell, this is readily permitted since the cell walls Which have been supersoftened, and the cushioning areas 82 may be displaced inwardly to the position shown by the dotted lines in FIG. 13.
Referring to FIGS. 14-16, a further embodiment of an egg carton is indicated generally at 210, this carton including, as indicated by general reference characters, a lower bottom or egg receiving section 212 hingedly connected at 214 to a lock flap 216. Hingedly connected to the bottom section 212, opposite the lock ap 216 as indicated at 218 is a substantially planar lid or cover member 220.
The bottom section 212 includes a plurality of cells 234 formed by vertically extending posts 242; it being noted fin this embodiment that ten egg cells are joined in the bottom section. The nature of the cells 234 and posts 42 is substantially identical in structure and function with the similar parts of the previously described embodiment and thus further description of the sirnilar portions appears to be unnecessary.
When the posts 242 as well as previously described posts 42 are initially formed, they may have a transverse aperture 243 therein which will have an annular rib 245 thereabout; see FIG. 16, within the post, after the posts are reformed as previously described.
The bottom section 212 includes peripheral, marginal flange portions 244 which extend into the hinges 214 and 21S. The lock ap 216 includes forwardly projecting lock buttons 232 which will cooperate with apertures 230 in the forward wall 228 of the lid 220.
The lid 220 includes a substantially planar top 222 which will abuttingly engage the upper surface of the posts 242, and includes marginal flange portions 226 which will seat on the marginal ange portions 244 of the bottom section 212.
The lid also includes diverging end walls 246 and 248 including upwardly extending notched-out portions 250 and 252, respectively, which are bordered by outwardly projecting U-shaped flange portions 254 and 256, respectively. These notched-out portions, as clearly seen in FIG. 15, provide a through passage within the closed cartons to facilitate air movement for ventilation and refrigeration i.e. maintain uniform temperatures at storage and distributing facilities. The anges 254 and 256 reinforce the openings 250 and 252 for maintaining structural strength during vertical loading and shocks to the closed cartons. The apertures 25), 252 afford a saving in the amount of pulp used in carton production, and afford the consumer means to examine the carton contents.
Thus there has been provided a substantially universal 4separator post construction which will accommodate an unusually large range -of egg sizes. Not only does this eliminate the necessity for producing a plurality of different ranges of sizes of egg cartons, but it also eliminates the excessive stock a packer must normally carry in his egg packing room, and further the eggs are protected and cushioned against breakage and damage during handling. The memory position of the separator post walls facilitates denesting.
Briefly in review, the segments 62, 64, 66 -of the cells 34 provide relatively rigid stable outer wall construction, and the cushioning areas of the separator post walls provide an unexpected versatility in a single carton due to the utilization of the memory after-forming phenomena incorporated in forming and then reforming the separator post. The rigid outer walls in the cells protect the eggs against lateral shock, and the cushioning areas absorb the shock that is transmitted to the eggs. The cushioning areas may be displaced for different size eggs and tend to stabilize the eggs against rattling within the cells. It will be noted that the elliptically shaped cushioning areas of the cell walls extend above and below the upper margin `of the cell forming portions of the carton.
Still further, the novel cells may be utilized in cartons of different capacities, and the lid may include ventilation examination apertures without loss of structural strength.
Although the egg cartons are disclosed as being constructed from pulp fiber, the use of vother materials such as plastic, for example, is contemplated as being within the scope of the invention.
Additionally, it is to be understood that the post wall of FIGS. 7 and 11 could be used without the after-forming step disclosed in FIGS. 8 and 12 to ultimately provide the post of FIGS. 9 and 13.
It will be obvious to those skilled in the art that various changes may be made without departing from the scope of the invention, and therefore the invention is not limited to what is shown in the drawings and described in the specification but only as indicated in the appended claims.
What is claimed is:
l. In an egg packing element, a cell having a substantially vertical wall, said wall including a portion having an elongated closed geometric outline with the major axis thereof extending vertically, said wall including a relatively thin strip extending vertically along the major axis of said elongated closed geometric outline, said vertical strip comprising natural random formation ibers, sazid elongated, closed geometric outline extending around said vertical strip and comprising reoriented fibers extensively disturbed by reforming pressures.
2. The structure of claim l; and at least one adjacent egg-contacting wall being provided with a lower portion when viewed from the cell interior convex in horizontal section, said one wall including an upper portion which is generally planar and diverges upwardly from said convex portion, whereby the cell strength is materially increased without interference with egg room and protection for an egg accommodated in said cell.
3. The structure of claim 1 wherein said relatively thin strip includes a rib portion projecting into said cell to afford substantially tangential Contact with an egg disposed in said cell.
4. In a molded pulp egg carton, an egg receiving section having a plurality of egg receiving cells each cornprising a bottom wall, four wall segments spaced from each other and having a contact point for supporting an egg at four circumferential points within said cell, two of said wall segments comprising an outer wall of said egg. receiving section, the other two wall segments comprising inner wall segments, each of said outer wall segments having a substantially rigid area in which the egg contact points thereof are located, each of said inner wall segments having a exible area in which the egg contact points thereof are located, said egg receiving section comprising an upper margin dening the upper limit of said cells, at least one of said inner wall segments of said cells comprising a substantially planar triangular section of a frusto-pyramidal separator post terminating above the upper margin of said egg receiving section, said triangular planar section including a vertically disposed, elongated, closed geometric cushioning area containing said egg contact point and having a maximum width terminating at a point disposed below said upper margin of said cells and adjacent the outer marginal edge of said triangular planar section, said cushioning area including a vertically extending relatively thin strip -of normally oriented fiber extending along the major axis thereof and the remaining portions of said cushioning area comprising reoriented fiber extensively disturbed by reformmg.
5. The structure of claim 4; said cushioning area being substantially elliptical and substantially more flexible than adjacent portions of said frusto-pyramidal separator posts and providing and forming a variable capacity cushioning pocket for an egg disposed in said cell.
6. The structure of claim 5; said cushioning area having outer and inner surface fibers having a substantially interdigitated relation for substantially relative movement with respect to each other.
7. In a molded egg carton comprising a cellular bottom section including a plurality of hollow up-posts and front and rear walls diverging from a bottom wall, the improvement comprising circumferentially spaced egg bearing surfaces, one of said egg bearing surfaces Comprising a generally vertical wall, said wall including a portion having an elongated, closed geometric outline with the major axis thereof extending vertically, said wall including a relatively thin strip extending vertically along the major axis of said elongated, closed geometric outline, said vertical strip comprising natural random forma-tion bcrs, said geometric outline extending around said vertical strip and comprising reoriented fibers extensively disturbed by reforming pressures.
8. The structure of claim 7 wherein said relatively thin strip includes a rib portion projecting into said cell to afford substantially tangential contact with an egg `disposed in said cell.
9. The structure of claim S wherein said cell includes a section having an egg contact area of unoriented liber spaced from said egg cushioning portion and surrounded by relatively rigid fiber.
10. The structure of claim 9 wherein said egg contact area includes a flute portion for obtaining minimum contact of an egg in said cell.
References Cited by the Examiner UNITED STATES PATENTS 1,963,134 6/34 Keiding 162-223 2,268,702 1/42 De Reamer 217-265 2,270,030 l/42 Benoit 229-29 X 2,423,756 7/47 Chaplin 229-25 2,515,113 7/50 Chaplin 162-223 2,591,446 4/52 Lennon 229-25 2,600,130 6/52 Schilling 229-2.5 2,655,303 10/53 Cox 229-25 2,662,659 12/53 Putnam 217-265 2,885,136 5/59 Grant 217-265 2,924,367 2/ 60 Lord et al. 229-25 2,974,847 3/61 Hurn et al. 229-25 2,979,245 4/ 61 Randalll et al. 229-25 3,016,176 1/62 Reifers etal 217-265 X L) GEORGE O. MLSTON, Primary Examiner,