US2652696A - Lettuce pack - Google Patents

Description

p 1953 F. H. MCCANN ET AL LETTUCE PACK 3 Sheets-Sheet 1 Filed April 2, 1952 IN VE N T0 R S FRANK HUBERT' M (NV/V WALTER d. SCHWERTFEGEI? Sept. 22, 1953 Filed April 2, 1952 F. H. M CANN ET AL LETTUCE PACK 5 Sheets-Sheet 2 ENVENTORS FRANK HUBERT MC m/v/v MQLTER a, SCHWERTFEGER THE/1K ATTORNEYS Sept. 22, 1953 F. H. MCCANN ET AL LETTUCE PACK Filed April 2, 1952 3 Sheets-Sheet 3 Tfeger 1 VENTORS Frank Hu ertMcCann Miter J.Schwer BY M a. M

ATTORNEY Patented Sept. 22, 1953 LETTUCE PACK Frank Hubert Mcflann, Salinas, Calif., and Walter J. Schwertfeger, West Englewood, N. J., assignors to. lone McCann, Salinas, Calif.

Application April 2, 1952, Serial No. 279,998

14 Claims.

- ment, it is known to pack the lettuce, butt ends up, in layers within the crate, with sheets between the layers, and finely divided ice on each sheet and below the nexthigher layer of lettuce. Such practice. whereby the butt ends of the lettuce are protected from direct contact with the ice, is disclosed in McCann Patent No. 2,287,693. These bodies of ice, disposed between the sheets and the next higher layers of lettuce, are confined edgewise by the sides of the crate, and consequently the ice may be distributed laterally in. uniform manner, to provide uniform refrigeration to the adjacent layers of lettuce.

When the crate has been filled, and prior to the application of the cover, the lettuce heads in the top layer ordinarily extend somewhat above the upper edge of the crate. Before the present invention, an additional sheet, ordinarily of fiat paper, has been placed over this top layer of lettuce, and ice shoveled thereon.. This ice has tended to slide oil the edges of the fiat sheet, leaving a dome of ice at the center of the sheet tapering to a substantial absence of ice near the edges of the sheet. Subsequently, in the normal procedure of closing the crate, the paper lining of the crate has been folded over this upper layer of ice, downward pressure applied, and the cover nailed down.

When lettuce crates packed as above described have reached their destination, it has been found in many instances, upon unpacking the crates, that the quantity of ice retained on the top sheet at the time of packing has been insufi'icient to provide adequate refrigeration. This applies particularly to that portion of the journey after the crates have been removed from refrigerator cars and until they have reached their final destination. Such inadequacy of refrigeration affects the lettuce heads in the top layer, and principally those in the marginal portions thereof.

By the present invention there is provided an effective and economical ice-support and protector whereby the disadvantages outlined above may be overcome, and whereby a more substantial and uniform body of finely divided ice readily may-be supported above the top layer of lettuce in a crate, while protecting the butt ends of such lettuce from direct contact with the ice.

sealing of the crate.

In the crating of lettuce the lettuce heads are generally packed in layers with the top of the upper layer extending somewhat above the upper edge of the crate, before the crate is covered. The top of this layer is usually crown shaped apparently by reason of the closeness of packing.

In order to provide an effective top ice-support and protector sheet for a crowned pack, the protector sheet is advisedly preformed to substantially conform to the crowned surface of the uppermost layer of lettuce and is made flexible enough to allow manual distortion thereof to compensate for the inevitable misalignments and differences in size and degree of slope of the crowns in the various crates. strong enough at the edges thereof to retain the refrigerating layer of ice during the trip to the market. The crowning assures that the sheet will stay in place on the lettuce heads without spinning around while the ice flakes are poured over it, thereby simplifying the handling and This preformed shape of the ice-support further permits a more uniform distribution of' the refrigerating layer of ice in contrast to the prior art's centrally located dome of ice.

According to the present invention, an essentially uncrowned packing sheet can also be used, as an ice-carrier. However, such a fiat sheet, when placed ona crowned layer, is only supported at its center and is very readily rotated around this center in response to even minor handling operations. In even slightly rotated condition it will not properly cover the heads and will permit ice to slip down through the uncovered. portions. This reduces the effectiveness of the pack in protecting the upper layers of heads. However, the fiat sheet also proves very useful with crowned packs; being much better than the ice supports previously used. This is particularly true where care is taken to hold the uncrowned sheet in its proper position.

The ice-support and protector of this invention may be used for a lettuce pack as well as for shipping other articles. It comprises a unitary, flexible, felted fibrous cellulosic sheetwhich is conformable to portions of lettuce heads, and which has a continuous upwardly extending angular peripheral wall arranged to retain ice within the confines of the sheet, This use of an angled upwardly extending wall' preserves the flexibility of the cellulosic sheet and eliminates the likelihood of comer-breaks, a common fault in the prior art type ice-support.

In order that the sheet may be conformable to Such a sheet is the lettuce heads with which it is to come in contact, it is shaped to provide a plurality of downwardly opening domes arranged to encompass portions of lettuce heads. In a preferred embodiment of the invention, the sheet may be sloped between said domes to a plurality of depressions, and drainage apertures may be provided in the sheet at said depressions, through which water melted from ice supported on the upper sheet may drip onto the lettuce heads directly below the sheet. This helps keep the lettuce heads suitably moistened.

The ice-support and protector of this invention may be formed into the desired shape from a flat sheet of felted fibrous cellulosic material. In a preferred embodiment of the invention, however,

the sheet may be formed directly to the desired shape by suction molding from an aqueous slurry of paperor wood-pulp. Conveniently the sheet may contain ingredients to impart high wet strength to the ice-support and protector so that it may be sure to retain its unitary and integral character during long contact with wet lettuce heads below and with finely divided ice above,

size depending in part upon the number and size of lettuce heads over which it is to be placed.

While the ice-support and protector is described herein particularly with respect to its use in connection with the packing of lettuce, it will be understood that advantages of the invention may be utilized in connection with the packing of fruits and other vegetables.

In the drawings illustrating specific embodi- Figures 4 and 5 are longitudinal and transverse sectional views, respectively, of a modified form of ice support and protector;

Figure 6 is a side view having a cut-away section illustrating the use of the support-protector of Figure 1 in packing a crate of lettuce;

Figure 7 is a side view of a lettuce crate packed with lettuce and showing a further modified form of ice-supporting and protective sheet in broken vertical section, said sheet being disposed on top of the upper layer of lettuce and with finely divided ice supported on its upper surface and within the confines of the sheet but before the cover is afilxed; and

Figure 8 is a view similar to Figure 7 after the cover has been pressed down on and nailed to the crate, showing the crate in front elevation and the cover and the modified form of icesupporting and protective sheet in section.

Referring in detail to the specific form of the invention illustrated in Figures 1, 2, 3 and 6 and its mode of incorporation in a lettuce crate, there is shown a sheet 32 of unitary, flexible, felted fibrous cellulosic material, The sheet 32 is shaped to provide a plurality of vertically extending and downwardly opening domes 34 which are arranged to encompass portions of the lettuce heads 36 (Figure 6) disposed therebeneath in a crate 38. The domes 34 conveniently may be continuously curved in vertical section. The number, size and location of domes 4 are arranged to correspond to the lettuce heads to be packed in a given instance. The sheet 32 illustrated is shown as provided with twenty domes 34 arranged in four rows, five domes in a row, but any desired arrangement of domes may be used.

The sheet 32 is provided with a continuous peripheral side wall 40 shaped to retain ice within the confines of the sheet 32. The side wall 43 extends angularly upwardly to a substantially uniform height and at its upper edge it is shown as flanged outwardly at 4| (see Figures 2 and 3). The flange 4i serves to stiffen the wall 40, and assists it to retain its shape, especially when the sheet 32 is supporting a quantity of ice.

The sheet 32 is shown as provided with a plurality of depressions 42 between adjacent domes 34, and with a plurality of marginal depressions 44 located between domes 34 and the side wall 40. The depressions 42 and 44 are provided with apertures 46 and 48 respectively through which water from melted ice supported on the sheet 32 may pass downwardly through the crate 38 between the heads of lettuce 36.

The sheet 32 is shown as sloped downward at 50 between the domes 34 to depressions 42 to provide for more ready drainage into depressions 42 and through apertures 46. The sheet is similarly sloped downward at 52 between the side wall 40 and domes 34 adjacent thereto to provide for drainage into depressions 44 and apertures 48. At the comers, sheet 32 is sloped downward at 54 to facilitate drainage into adjacent depressions 44 and apertures 48.

The downwardly sloped portions 52 and 54 together with the depressions 44 form a continuous marginal trough varying in depth, as shown in Figure 2 and Figure 3. Thus at its shallowest portion the marginal trough extends from the flange 4| to the highest part of slope 54, and at its deepest portion the trough extends from thefiange 4i to the depression 44. The upwardly angularly extending peripheral side wall 40 therefore is arranged to retain ice within the confines of the sheet 32.

The form of the invention illustrated in Figures 2 and 3 is particularly adapted for use with the packing method in which the lettuce heads are packed with the uppermost surfaces in a centrally crowned arrangement. As shown in Figure 2, the ice-support is shaped to have convex curvatures near its respective ends with a cen- This form of the invention, as is clearly illustrated in Figures 2 and 3, includes the angularly upwardly extending wall portions 40 having a continuous laterally extending flange 4i at the may be shoveled or otherwise placed on the upper surface of the ice-support 32. The contour and construction of the support 32 is such as to retain the ice in relatively uniform distribution within the confines of such support. when the cover is fastened in place over the ice-covered support, the depending end portions are deflected downwardly under the pressure of the ice and forced into tight contact along the flange portions 4| of the angularly extending walls 40 with the inner surfaces of the side and end walls of the crate 38. It will be apparent that forming the wall section 40 of the support 34 as being angularly and upwardly extended provides a much needed flexibility which permits such wall portions to frictionally abut the crate end and wall surfaces to provide a tight bond therebetween and prevent the escape of ice from the upper layer into the lower sections of the crate. This action is aided by the provision of the flange portions 4| on the'angularly extending walls 40, which portions upon deformation of the support 34 within the crate 38 over the crowned uppermost layer of lettuce provide a contiguous border between the end and wall surfaces of the crate and the ice-support 34. In this construction, as is illustrated in Figure 6, the distribution of the refrigerating layer of ice is made relatively uniform throughout the length and breadth of the ice-supporting layer 34. Instead of the prior art type of centrally located mass of ice, the refrigerating layer is distributed as a protective coating on the top of the support 34. After the ice is placed over the support, the cover 82 is forced downward thereover under pressure and nailed to the sides of the crate in the usual manner.

It will be obvious that with the instant invention there is less likelihood of losing ice from the refrigerating layer to the lower sections of lettuce due to the gripping action of the resilient flanges 40. It will be further noted that this use of a resilient preformed pulp molded ice-support permits the packer to readilyadjust the support in the proper relation over the lettuce within the crate without any danger of the support thereafter slipping off or becoming misaligned as was common with the prior art type of sheet paper or cardboard protector.

Figures 4 and 5 illustrate a modification of the ice support and protector of Figures 1 through 3, inclusive. In this embodiment the longitudinal extent of the ice-support 34 is formed identical identical to that of Figures 1 through 3, inclusive and need not be further described.

- The double-crowned sheet construction is also suitable for use with lettuce packs that for one reason or another are not crowned. The normal yieldability of either crowned form of sheet permits it to conform to the shape of the lettuce heads notwithstanding the rigidifying effect of its peripheral retainmgwalls.

A still further modification is illustrated in use in Figures 7 and 8. In this form of the invention the ice support 2 is formed to have a substantially uncrowned or fiat horizontally extending configuration both lengthwise and crosswise of the surface of the support; the transverse cross section of this form of the invention being identical to that illustrated in Figure 5 The construction of the surface of this support is substantially identical to that of Figures 1 through 3, inclusive, and includes a molded cellulosic fibrous sheet 2 having a plurality of vertically extending, hollow, convex domes 4 with intermediate troughs 28 therebetween and an upwardly and angularly extending side and end wall portion l0 having a continuous horizontally disposed flange I l at the top thereof. The lengthwise configuration of the support is substantially fiat horizontally as indicated in Figure 7 where the support is shown in cross section along two separate longitudinal segments.

This fiat or uncrowned form of ice-support is alsoutilized with lettuce heads packed with the upper layers in crowned or uncrowned condition, and is adapted to be readily placed over the uppermost horizontal layer of lettuce and to lie in intimate contact therewith as illustrated in Figure 8. As shown the lettuce when first packed in the crate normally extends above the top surface of the sides and ends thereof. The support 4 is then placed over these extended heads and covered with finely crushed ice 38. The weight of the ice 30 settles the resilient support into firm contact with the, lettuce heads, the

angularly extending walls It retaining the refrigerating layer of ice within the confines of the support and preventing it from spilling without the crate. Paper sheets 28 and 28 placed within the crate are then folded over the top of the refrigerating layer of 'ice and the cover section 32 folded thereabove and pressed down upon the refrigerating layer of ice and ice-support 2 under pressure and subsequently, secured to the edges of the crate 8. As viewed in Figure 8 this method of packing results in a fairly uniform distribution of ice throughout the surface of the support 4 confined by the cover 28, but as is clearly indicated in such figure the major portion of the ice is concentrated in a vertically extending bulge in the center of the crate which gradually decreases in cross sectional area as it progressively slopes towards the sides of the crate.

- With the use of the present ice-support 4 such with that of the embodiment of Figures 1 and 2,

ice distribution does not produce any harmful results nor reduce the amount of refrigerating ice over the uppermost layer of the lettuce heads due to the extremely flexible character of the support 4 and the friction gripping action of the flange section i I of the angularly extending walls I!) of such support.

The various forms of the present invention provide many advantages over the prior art sheet paper or rigid cardboard protectors in that while being readily flexible and adaptable to conform to various miscellaneous sizes and shapes of lettuce in the packed crates it is still strong enough to resist breaking at the corners and the marginal area of the crate, thus preventing any loss in the refrigerating layer of ice as was a common fault withth prior art structures. The angularly and upwardly extending wall portions in are so designed to impart sufiicient rigidity to the body portion of the sheet 2 without destroying this flexible character. If the wall por tions were designed to be perpendicular to the surface of the sheet 2, the stresses imposed upon such sections under the load of the refrigerating layer of ice and the pressure of the cover would readily cause splitting and breaking in the marginal areas of the crate. For the purposes of the present invention walls Hi can be disposed at angles of between about 50 and 80 degrees with respect to the adjacent floor portions of the sheet.

As many apparently widely difierent embodiments of this invention may be made without.

departing from the spirit and scope hereof, it is to be understood that the invention is not limited to the specific embodiments hereof, except as defined in the appended claims.

What is claimed is: I

1. An ice support and protector for a lettuce pack and the like, a unitary molded felted fibrous cellulosic sheet, said sheet containing a plurality of vertically extending, shallow and downwardly opening domes arranged throughout the surface thereof, an angularly extending continuous peripheral side wall bounding the edges of said sheet, said side wall being directed upwardly at an angle with respect to .the vertical, and a horizontally extending and continuous flange surface being integrally formed on the uppermost edge of said wall.

' 2. The combination set forth in claim 1 in which said sheet is generally rectangular in configuration and is crowned lengthwise to bring its end portion lower than its center.

3. The combination setv forth in claim 1 in which said sheet is rectangular in configuration and is crowned transversely to bring its end portion lower than its center.

4. The combination set forth in claim 1 in which said sheet is substantially uncrowned.

5. An ice support and protector for crated heads of lettuce, having a substantially crowned upper bounding surface, said supportconsisting of a molded fibrous cellulosic sheet having a plurality of shallow, raised domes thereon, a contiguous peripherally and vertically extending wall formed on the edges of said sheet, said wall extending at an angle with respect to the vertical, said sheet being pro-formed to have an overall surface configuration of a substantially convex nature to snugly fit said crowned bounding surface of the packed lettuce heads, and said domes being shaped to overlie and frictionally engage the individual heads.

6. The combination set forth in claim 5 in which the convex surface configuration of said sheet includes end portions having a convex configuration and a central section interconnecting said end portions and having a fiat configuration.

7. The combination set forth in claim 5 in which said sheet and said end walls are flexible.

8. An ice support and protector for a lettuce formed at the intersections of the lowermost slopes of said domes and said latticework, a peripheral wall bounding the edges of said sheet and being integrally formed therewith, said wall extending upwardly at an angle to the vertical.

9. The combination set forth in claim 8 in which a continuous trough-like undulating latticework is formed between said bounding wall and the edge slopes of adjacent domes.

10. The combination set forth in claim 8 in which the said domes crowned configuration of said sheet extends in a lengthwise direction of said sheet, and said sheet has a substantially uncrowned horizontal transverse configuration.

11. An ice-support and protector for a lettuce pack and the like comprising a unitary molded felted fibrous cellulosic sheet, said sheet being shaped to provide a plurality of shallow downwardly opening domes arranged to contact the tops of a layer of packed lettuce heads. said sheet having a. continuous peripheral side wall extending upwardly at an angle with respect to the vertical to retain finely divided ice within the confines of its upper surface and to provide the sheet with an ice-retaining flexibility adequate for deformation over a packed layer of lettuce heads and under a lid bowed over the heads and fastened to side walls below the levels of the tops of the heads.

12. The combination as defined by claim 11 in which the sheet is sloped between the domes to a plurality of depressions provided with drainage apertures for water formed by the melting of the retained ice.

13. The combination as defined by claim' 11 in which the sheet contains about to 3% of a high-wet-strength-imparting resin.

14. The combination as defined by claim 11 in which the side walls are fianged outwardly at their upper edges to strengthen the deformable walls.

FRANK HUBERT McCANN.

WALTER J. SCHWERTFEGER.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date D. 138,968 Wackter Oct. 3, 1944 160,948 Peck Mar. 16, 1875 505,873 Bomgardner Oct. 3, 1893 585,782 Phillips July 6, 1897 1,223,872 Hartley et al. Apr. 24, 1917 1,310,161 Johnson July 15, 1919 1,603,693 Hiatt Oct. 19, 1926 1,608,422 Plass Nov. 23, 1926 2,186,352 Tracy Jan. 9, 1940' 2,254,406 Zarotschenzefi Sept. 2, 1941

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