CN117656424A - High-strength blow molding structure - Google Patents

Abstract

A blow-molded plastic frame for a portable, collapsible sign includes a first exterior portion, a second exterior portion spaced apart from the first exterior portion, and a pattern of structural reinforcing features formed in the first exterior portion and the second exterior portion. The pattern includes rows and columns of first depressions extending from the first outer portion into the hollow inner portion between the first outer portion and the second outer portion and rows and columns of second depressions extending from the second outer portion into the hollow inner portion. Each first recess has a first base plate comprising three first arms having rotational symmetry. Each first arm is rotated 120 ° from the other first arm. Each second recess has a second floor comprising three second arms having rotational symmetry. Each second arm is rotated 120 ° from the other second arm. The first floor of each first recess is aligned with the second floor of an adjacent second recess.

Description

High-strength blow molding structure

RELATED APPLICATIONS

The present application claims priority from U.S. patent application Ser. No. 17/500270, entitled "high Strength BLOW-MOLDED Structure (HIGH STRENGTH BLOW-MOLDED STRUCTURE)" filed on Ser. No. 10/13/2021, which is a continuation of U.S. patent application Ser. No. 16/299302, entitled "high Strength BLOW-MOLDED Structure (HIGH STRENGTH BLOW-MOLDED STRUCTURE)" filed on Ser. No. 3/12/2019; patent application 16/299302 was published as U.S. patent 11147377 at 2021, month 10 and 19, and claims priority to:

U.S. patent application Ser. No. 15/975915, entitled "high strength BLOW-MOLDED STRUCTURE" (HIGH STRENGTH BLOW-MOLDED STRUCTURE) ", filed 5/10/2018, published as U.S. patent No. 10981319 at 20/4 of 2021 as a partial continuation;

U.S. provisional patent application No. 62/645216 entitled "high strength BLOW-MOLDED STRUCTURE" (HIGH STRENGTH BLOW-MOLDED STRUCTURE) ", filed on 3/20 of 2018;

U.S. design patent application No. 29/640679 entitled "BLOW-MOLDED STRUCTURE" (as part of a continuation), filed on 3/16 in 2018, published as U.S. design patent No. D884,487 on 19 in 2020; and

U.S. design patent application No. 29/640977 entitled "BLOW-MOLDED STRUCTURE" filed on 3/19 in 2018, published as U.S. design patent No. d909,802 on 9 in 2021;

the entire contents of these patents are incorporated herein by reference.

Technical Field

The present disclosure relates to structures constructed from blow-molded plastic, and in particular to high strength, low weight blow-molded plastic structures.

Background

Various items such as tables, chairs, dividers, walls, sporting equipment, and signs are made of plastic. To reduce the weight of the article, blow-molded plastic is typically used. The blow molded plastic structure has an outer wall enclosing a hollow interior space. While the hollow interiors make these structures lightweight, the hollow interiors of such blow molded articles also reduce the strength of the article such that the article is not able to support a significant amount of weight or force.

It is well known that reinforcing ribs made of metal or other durable material may be added to blow molded structures to increase the load bearing strength of the structure. However, such strengthening ribs typically add significantly to the weight of the structure and may create stress points at the attachment locations that lead to mechanical failure of the structure.

The reinforcing ribs may also be integrally formed from plastic during the blow molding process to increase the load carrying capacity of the blow molded structure. Such ribs may extend over portions of the length and width of the structure to provide load bearing support for the structure. However, integrally formed ribs generally require the use of thicker walls that increase the weight of the structure, increase production time, and increase the cost of producing such structures. The ribs may also interfere with other components of the structure, such as the support legs of a table top constructed from blow-molded structures.

In view of the foregoing, there is a continuing need for blow-molded structures having improved load carrying capability and simple lightweight configurations.

Disclosure of Invention

Accordingly, embodiments described herein provide a blow molded plastic structure having a hollow interior portion formed during a blow molding process. In a preferred embodiment, the blow molded plastic structure comprises: a first outer portion; a second outer portion spaced apart from the first outer portion; and a structural reinforcement feature pattern integrally formed in the first and second outer portions. The hollow inner portion is disposed between the first outer portion and the second outer portion, wherein a distance between the first outer portion and the second outer portion is defined by a first height. The pattern of structural reinforcing features includes a plurality of first recesses and a plurality of second recesses. The first depressions extend from the first outer portion into the hollow inner portion and are arranged in rows and columns. Each first recess includes a first floor spaced apart from the first outer portion. The first base plate includes a plurality of first arms, wherein one or more of the first arms is rotated a first angle relative to an adjacent one of the first arms. The second recesses extend from the second outer portion into the hollow inner portion and are arranged in rows and columns. Each second recess includes a second floor spaced apart from the second outer portion. The second base plate includes a plurality of second arms, wherein one or more of the second arms is rotated a second angle relative to an adjacent one of the second arms. In a preferred embodiment, the first floor of each first recess is aligned with the second floor of an adjacent second recess.

In some embodiments, the plurality of first arms comprises three first arms, the plurality of second arms comprises three second arms, the first angle is 120 °, and the second angle is 120 °.

In some embodiments, the center-to-center spacing between the first recesses in each row of first recesses is greater than three times the first height, and the center-to-center spacing between the second recesses in each row of second recesses is greater than three times the first height.

In some embodiments, the center-to-center spacing between the first depressions in each row of first depressions is about 63 millimeters and the center-to-center spacing between the second depressions in each row of second depressions is about 63 millimeters.

In some embodiments, the center-to-center spacing between the first recesses in each column of first recesses is greater than twice the first height, and the center-to-center spacing between the second recesses in each column of second recesses is greater than twice the first height.

In some embodiments, the center-to-center spacing between the first depressions in each column of first depressions is about 50 millimeters and the center-to-center spacing between the second depressions in each column of second depressions is about 50 millimeters.

In some embodiments, the first height is in a range of about 13.7 millimeters to about 20.3 millimeters.

In some embodiments, the first floor of each first recess is spaced from the first outer portion by a second height in the range of about 7.5 millimeters to 11.5 millimeters.

In some embodiments, the second floor of each second recess is spaced from the second outer portion by a third height in the range of about 2.5 millimeters to 6.5 millimeters.

In some embodiments, the first floor of each first recess is spaced apart from the second floor of an adjacent second recess by a fourth height in the range of about 2 millimeters to 5 millimeters.

In some embodiments, each first arm in the first floor of each first recess is aligned with a respective one of the second floors of adjacent second recesses.

In some embodiments, blow-molded plastic structures comprise: a portion of a portable, collapsible sign frame.

In another aspect, embodiments described herein provide a blow molded plastic frame for a portable, collapsible sign. In a preferred embodiment, the frame comprises: a first outer portion; a second outer portion spaced apart from the first outer portion; and a structural reinforcement feature pattern integrally formed in the first and second outer portions. The hollow inner portion is disposed between the first outer portion and the second outer portion, wherein a distance between the first outer portion and the second outer portion is defined by a first height. The pattern of structural reinforcing features includes a plurality of first recesses and a plurality of second recesses. The first depressions extend from the first outer portion into the hollow inner portion and are arranged in rows and columns. Each first recess includes a first floor spaced apart from the first outer portion. The first base plate comprises three first arms having rotational symmetry, wherein each first arm is rotated 120 ° from the other first arm. The second recesses extend from the second outer portion into the hollow inner portion and are arranged in rows and columns. Each second recess includes a second floor spaced apart from the second outer portion. The second base plate comprises three second arms with rotational symmetry, wherein each second arm is rotated 120 ° from the other second arm. In a preferred embodiment, the first floor of each first recess is aligned with the second floor of an adjacent second recess.

The foregoing and other aspects, features and advantages of the embodiments disclosed herein will become more apparent from the following detailed description of the preferred embodiments and the appended claims.

Drawings

The drawings comprise a plurality of figures illustrating aspects of the preferred embodiments of the present disclosure and further illustrating advantages and features of the disclosed embodiments. It is to be understood that the drawings illustrate only preferred embodiments and are not intended to limit the scope of the claims. Thus, the disclosed embodiments are described and explained with additional specificity and detail through the use of the accompanying drawings in which:

FIG. 1 is a partial perspective view of a second exterior portion of a blow molded plastic structure according to a first embodiment;

FIG. 2 is a partial top view of a second exterior portion of a blow molded plastic structure according to a first embodiment;

fig. 3A, 3B and 3C are partial cutaway perspective views of blow molded plastic structures according to a first embodiment;

fig. 4 is a cut-away perspective view of a portion of a table top including a blow-molded plastic structure in accordance with a first embodiment;

fig. 5 is a top view of a second outer portion of a table top including a blow-molded plastic structure in accordance with the first embodiment;

Fig. 6 and 8 are perspective views, not to scale, of a table including blow-molded plastic structures according to the present disclosure;

FIG. 7 is a perspective view, not to scale, of a panel comprising a blow molded plastic structure according to the present disclosure;

FIG. 9 is a perspective view, not to scale, of a chair including a blow molded plastic structure according to the present disclosure;

fig. 10A and 10B are cutaway perspective views of a blow molded plastic structure according to a second embodiment;

FIG. 11 is a partial top view of a second outer portion of a blow molded plastic structure according to a second embodiment;

FIGS. 12A and 12B are partial top plan views of a second exterior portion of a blow molded plastic structure according to a third embodiment;

FIGS. 12C and 12D are cross-sectional views of a blow molded plastic structure according to a third embodiment;

FIGS. 13A and 13B are partial top plan views of a second exterior portion of a blow molded plastic structure according to a fourth embodiment;

FIG. 13C is a cross-sectional view of a blow molded plastic structure according to a fourth embodiment;

FIGS. 14A and 14B illustrate opposite sides of a panel of a portable, collapsible sign having a blow-molded plastic structure according to a fifth embodiment;

FIGS. 15A and 15B illustrate detailed views of opposite sides of the panel of FIGS. 14A and 14B;

FIG. 16 shows a cross-sectional view of the panel shown in FIGS. 14A and 14B; and, a step of, in the first embodiment,

fig. 17A to 17E show detailed views of portions of the panel shown in fig. 15A and 15B.

Detailed Description

As described above, the present disclosure generally designs blow-molded structures having enhanced strength and light weight. While strength and weight are important considerations, it should be appreciated that the blow-molded structures described herein may be suitable for use with other structures that do not require strength and light weight.

As used herein, the terms top and bottom, front and rear, right and left, horizontal and vertical, and rows and columns are intended to provide an understanding relative to the drawings and are not intended to limit the orientation of the disclosed structures. The blow-molded structures described herein may be disposed in a variety of desired locations, including various angles, sideways, and even upside down.

First embodiment

Referring now to fig. 1 and 2, a portion of a blow molded plastic structure 10 according to a first embodiment of the present invention is shown in perspective and top view. The structure 10 includes a first outer portion 12 and a second outer portion 14, the second outer portion 14 being generally spaced apart from the first outer portion 12. In some embodiments, the first outer portion 12 is generally planar. The first outer portion 12 and the second outer portion 14 enclose a hollow inner portion 16 formed during the blow molding process. In particular, the present disclosure relates to a structural reinforcement feature pattern that includes a tripodal recess 18, such as a pattern of tripodal recesses 18 within a dashed box 20, the tripodal recess 18 being formed as part of the second outer portion 14 of the structure 10. Each recess 18 extends towards the first outer portion 12 of the structure. The depressions 18 are arranged in rows 22 and columns 24 in the second outer portion 14 of the structure 10, and this pattern may be repeated over a substantial portion of the second outer portion 14 of the structure. As shown in fig. 4 and 5, the rows 22 and columns 24 may be arranged such that each tripod recess 18 is closely adjacent to the other tripod recess 18 in the adjacent row 22 and column 24 over a substantial portion of the second outer part 14.

Referring now to fig. 2, a top view of the second outer portion 14 of the first embodiment of the structure 10 is shown. Each recess 18 is centered on a three-sided island 26 spaced from the first outer portion 12. Each depression 18 also includes dimples, shown as dimples 28a,28b and 28c, adjacent each side of the three-sided island 26. Thus, as shown, indentations 28a-c and islands 26 form the central portion of tripod recess 18 in second outer portion 14 of structure 10. In the first embodiment, the center-to-center spacing D5 between the dimples 28a-c within each depression 18 is in the range from about 11mm to about 14mm, and is preferably 12.5mm. The centerline of the tripodal depression 18 of each row 22a is spaced from the adjacent row 22b by a distance D1, the distance D1 being in the range of about 62.3mm to about 68.8mm, and preferably 65.5mm. Likewise, the tripodal concavity 18 of each column 24a is spaced from the adjacent column 24b by a distance D2, the distance D2 being in the range of from about 65.5mm to about 72.5mm, and preferably 69.0mm. As shown, the dimples 28a in one row 22a are spaced apart from the dimples 28b and 28c in an adjacent row 22b by a distance D3, the distance D3 being in the range from about 47.9mm to about 52.9mm, and preferably 50.4mm. The dimples 28b in column 24b are spaced apart from the dimples 28c in column 24a by a distance D4, the distance D4 being in the range from about 53.3mm to about 58.9mm, and preferably 56.1mm.

While one preferred embodiment includes three dimples 28a-28c in each dimple 18 (which form a tripod-dimple arrangement), other embodiments may include more than three dimples. For example, one embodiment provides four dimples arranged in a rectangular layout within each dimple 18, forming a four-foot dimple structure. The multi-dimple depression structure is generally referred to herein as a multi-foot depression structure.

Referring to fig. 3A, 3B and 3C, a partial perspective, cross-sectional view of a first embodiment of a plastic molded structure 10 is shown. As shown, the structural reinforcement feature includes a convex region 30 of the second outer portion 14; the convex regions 30 are disposed between the recesses 18 and have a height H1 (distance from the first outer portion 12); the height H1 is in the range from about 17.5mm to about 19.3mm, and preferably 18.4mm. The radius of curvature R is in the range from about 22mm to about 26mm, and preferably 24.0mm.

As shown in FIG. 3B, within each dimple 28a-28c, the height H2 between the second outer portion 14 and the first outer portion 12 is in the range from about 2.5mm to about 3.3mm, and preferably less than about 16% of the height H1. In a preferred embodiment, the height H2 is 2.9mm. Additionally, within each indentation 28a-28c, the second outer portion 14 may be spaced apart from or in contact with the first outer portion 12 of the blow-molded plastic structure, depending on the load applied to the structure 10. The three-sided islands in the recess 18 have a center height H3, with the center height H3 preferably being greater than about 37% of the height H1 and less than about 2.4 times the height H2. The height H3 may range from about 6.0mm to about 7.5mm, and is preferably 6.9mm. The total depth of each dimple 28a-28c is (H1-H2), and preferably at least about 84% of the height H1.

As also shown in fig. 3B, an angle r is formed between the first outer portion 12 and the second outer portion 14. In various embodiments, the angle r may be in the range from about 38 ° to about 55 °. In a preferred embodiment, the angle r is about 40.6 °.

Such a pattern of structural reinforcing features (including the convex regions 30 and the concave portions 18) provides improved strength to the blow-molded plastic structure 10 and reduces the flexibility of the structure 10 under load.

In order to provide the desired structural properties of the blow-molded plastic structure 10, the plastic material of the second outer portion 14 generally has a material thickness T2, the material thickness T2 being in the range from about 2.06mm to about 2.54 mm. In the preferred embodiment shown in fig. 3C, the material thickness of the second outer portion 14 may vary throughout the convex region 30. Table 1 below provides three examples of material thickness at five points within the convex region 30. As listed in table 1, dimensions T1, H2, and H3 are slightly different in each example. As will be appreciated by those skilled in the art, the plastic thicknesses T2 and T1 of the outer portions 14 and 12 may vary depending on the particular application for which the blow-molded plastic structure 10 is being used. Thus, by using the structural configuration described herein, a lighter weight blow molded plastic structure 10 may be provided.

Example	T1	T21	T22	T23	T24	T25	H1	H2	H3
										1	2.15	2.25	2.27	2.29	2.25	2.06	18.39	2.87	6.85
2	2.51	2.45	2.36	2.49	2.54	2.38	18.52	3.06	6.73
										3	2.41	2.40	2.51	2.45	2.34	2.24	18.56	3.01	6.81

TABLE 1

Referring again to fig. 2, the area occupied by each depression 18 may be approximated by triangles 32 and the area occupied by each convex region 30 may be approximated by triangles 34. The combined total area of the triangles 32 is in the range of about 45% to about 55% of the total surface area of the second outer portion 14. Likewise, the combined total area of triangles 34 is in the range of about 55% to about 45% of the total surface area of second outer portion 14. Thus, the ratio between the total surface area of the convex regions 30 and the total surface area of the depressions 18 is in the range from about 0.82 to about 1.22. Each tri-sided island 26 may be approximated by a triangle 38, with the surface area of triangle 38 being less than or equal to about 4% of the surface area of triangle 32.

As shown in fig. 4 and 5, the recess 18 covers a substantial portion of the second outer portion 14 of the blow-molded plastic structure 10. Furthermore, although the recess 18 is shown and described as being located in the second outer portion 14 of the structure 10, the recess 18 may be formed in any desired portion of the structure 10. The depressions 18 may be spaced apart such that each depression 18 contacts an adjacent depression in its adjacent row 22 and adjacent column 24 over a substantial portion of the second outer portion 14.

While the tripod recesses 18, convex regions 30 and the three-sided islands 26 provide enhanced load bearing characteristics to the blow molded plastic structure 10, the second outer part 14 may include additional structures that provide enhanced resistance to the flexibility of the structure 10. In some embodiments, the second outer portion 14 further includes one or more cross beams 40 and 42, which may be integrally molded in the second outer portion 14 and may surround the area 44 including the tripod recesses 18, as shown. Additional reinforcement of the second outer portion 14 may be provided by raised lip 46, with raised lip 46 also integrally molded into the second outer portion 14 of structure 10.

Advantageously, the smaller distance between the depressions 18 increases the structural integrity and strength of the blow-molded structure 10, which allows the thicknesses T1 and T2 of the first and second outer portions 12 and 14 of the blow-molded structure 10 to be reduced. Thus, less plastic material may be used to construct the blow-molded plastic structure 10 due to the reduced thickness of the first and second outer portions. Minimizing the amount of plastic used to produce the structure 10 may reduce the cost of the structure, as well as reduce the cooling time, thereby reducing the manufacturing time of the structure 10. The faster cooling of the structure 10 enables the structure to be removed from the mold more quickly. The size and shape of the recess 18 may also reduce the need for multiple beams 40 and 42 to reduce the flexibility of the structure 10.

Non-limiting examples of articles that may incorporate blow-molded structure 10 may include: tables 48 and 50 (fig. 6 and 8), which may be foldable and/or collapsible tables; partition wall 52 (fig. 7), which may be used as a structural panel for a wall or partition or other portion of a building; a chair 54 (fig. 9) that may use the blow-molded plastic structure 10 as part of a seat 56 and/or a back support 58 thereof; and, a bench (fig. 10A).

Second embodiment

Referring now to fig. 11, a top view of the second outer portion 14 of the second embodiment of the structure 10 is shown. As in the first embodiment, each recess 18 is centered on a three-sided island 26 spaced from the first outer portion 12. Each depression 18 also includes dimples, shown as dimples 28a,28b and 28c, adjacent each side of the three-sided island 26. Indentations 28a-c and island 26 form the central portion of tripod recess 18. In the second embodiment, the center-to-center spacing D5 between the dimples 28a-c within each depression 18 is in the range from about 16.2mm to about 19.8 mm. In a preferred embodiment, the distance D5 is 18.0mm. The centerline of the tripod recess 18 of each row 22a is spaced from the adjacent row 22b by a distance D1, the distance D1 being in the range from about 61.0mm to about 67.4 mm. In a preferred embodiment, the distance D1 is 64.2mm. Likewise, the tripodal concavity 18 of each column 24a is spaced from the adjacent column 24b by a distance D2, the distance D2 being in the range from about 49.1mm to about 54.3 mm. In a preferred embodiment, the distance D2 is 51.7mm. As shown, the dimples 28a in one row 22a are spaced apart from the dimples 28b and 28c in an adjacent row 22b by a distance D3, the distance D3 being in the range from about 42.6mm to about 47.0 mm; and the dimples 28b in column 24b are spaced apart from the dimples 28c in column 24a by a distance D4, the distance D4 being in the range from about 28.7mm to about 31.7 mm. In a preferred embodiment, distance D3 is 44.8mm and distance D4 is 30.2mm.

Referring to fig. 10A and 10B, a partial perspective, cross-sectional view of a second embodiment of a plastic molded structure 10 is shown. As shown, the structural reinforcement feature includes an interspersed region 30 of the second outer portion 14, the interspersed region 30 being disposed between the depressions 18 and having a height H1 (distance from the first outer portion 12), the height H1 being in the range from about 16.0mm to about 17.8 mm. In a preferred embodiment, the height H1 is 16.9mm.

As shown in fig. 10B, within each dimple 18, the height H2 between the second outer portion 14 and the first outer portion 12 is in the range from about 3.6mm to about 4.8mm, and preferably less than about 25% of the height H1. In a preferred embodiment, the height H2 is 4.2mm. The three-sided islands in the recess 18 have a center height H3, with the center height H3 preferably being greater than about 49% of the height H1 and less than about twice the height H2. The height H3 may range from about 7.5mm to about 8.9 mm. In a preferred embodiment, the height H3 is 8.4mm. The total depth of each dimple 28 is (H1-H2), and preferably at least about 75% of the height H1.

As also shown in fig. 10B, an angle r is formed between the first outer portion 12 and the second outer portion 14. In various embodiments, the angle r may be in the range from about 38 ° to about 55 °. In a preferred embodiment, the angle r is about 44.2 °.

In order to provide the desired structural properties of the blow-molded plastic structure 10, the plastic material of the second outer portion 14 generally has a material thickness T2, the material thickness T2 being in the range from about 2.6mm to about 3.3 mm. The plastic material of the first outer portion 12 preferably has a material thickness T1, the material thickness T1 being in the range from about 3.1mm to about 3.8 mm. Table 2 below provides three examples of material thicknesses T1 and T2, and corresponding variations in height dimensions H1, H2, and H3.

Example	T1	T2	H1	H2	H3
						1	3.78	3.34	16.81	4.22	8.24
2	3.58	3.04	16.87	4.18	8.35
						3	3.07	2.62	16.88	4.07	8.45

TABLE 2

Third embodiment

Fig. 12A to 12D show a part of a blow-molded plastic structure 10 according to a third embodiment of the present invention. The structure 10 includes a first outer portion 12 that is generally planar as described in other embodiments, and a second outer portion 14, the second outer portion 14 being generally spaced apart from the first outer portion 12. The first and second outer portions enclose a hollow inner portion 16 formed during the blow molding process. The third embodiment includes a pattern of structural reinforcing features in the form of tripod recesses 18 integrally formed in the second outer part 14 of the structure 10. Each recess 18 extends towards the first outer portion 12 of the structure. The depressions 18 are arranged in rows 22 and columns 24 in the second outer portion 14, and this pattern may be repeated over a substantial portion of the second outer portion 14 of the structure. As shown in fig. 12A, the rows 22 and columns 24 may be arranged such that each tripod recess 18 is closely adjacent to the other tripod recess 18 in the adjacent row 22 and column 24 over a substantial portion of the second outer part 14.

In the third embodiment, all the recesses 18 in each row are rotationally flipped 180 ° relative to all the recesses 18 in the adjacent row. For example, in fig. 12A, all of the recesses 18 in row 22A are rotationally flipped 180 ° relative to all of the recesses 18 in row 22 b. In addition, all of the recesses in each column are rotationally flipped 180 ° relative to all of the recesses 18 in the adjacent column. For example, all of the recesses 18 in column 24a are rotationally flipped 180 ° relative to all of the recesses 18 in column 24 b.

As shown in fig. 12B-12C, each recess 18 is centered on a three-sided island 26 spaced from the first outer portion 12. Each depression 18 also includes dimples, shown as dimples 28a,28b and 28c, adjacent each side of the three-sided island 26. Thus, as shown, indentations 28a-c and islands 26 form the central portion of tripod recess 18 in second outer portion 14 of structure 10. In the third embodiment, the center-to-center spacing D5 between the dimples 28a-c in each depression 18 is in the range from about 11mm to about 14mm, and is preferably 12.5mm. The centerline of the tripodal recess 18 of each row 22a is spaced from the adjacent row 22b by a distance D6, the distance D6 being in the range from about 49.5mm to about 60.5mm, and preferably 55.0mm. Likewise, the tripodal concavity 18 of each column 24a is spaced from the adjacent column 24b by a distance D7, the distance D7 being in the range from about 49.5mm to about 60.5mm, and preferably 55.0mm. The centerline spacing between adjacent recesses 18 in each row and between adjacent recesses 18 in each column is about 99mm to about 121mm, and preferably 110mm. The diagonal centerline spacing D8 is about 70mm to about 86mm and preferably 78mm.

As shown in fig. 12D, the structural reinforcement feature includes the interspersed regions 30 of the second outer portion 14, the interspersed regions 30 being disposed between the recesses 18. The penetration region 30 has a height H1 (distance from the first outer portion 12 to the second outer portion 14) that is in the range of from about 29.7mm to about 36.3mm, and preferably 33.0mm. Within each dimple 28a-28c, the height H2 between the second outer portion 14 and the first outer portion 12 is in the range from about 5.0mm to about 6.0 mm. In a preferred embodiment, the height H2 is 5.5mm. Each dimple 28a-28c has a total depth (H1-H2), and preferably at least about 83% of the height H1. Additionally, within each indentation 28a-28c, the second outer portion 14 may be spaced apart from the first outer portion 12 of the blow-molded plastic structure or may contact the first outer portion 12, depending on the load applied to the structure 10. The three-sided islands 26 in the depressions 18 have a center height H3, with the center height H3 preferably being greater than about 20% of the height H1 and less than about 1.3 times the height H2. The height H3 may range from about 6.0mm to about 7.5mm, and is preferably 6.9mm.

In a third embodiment, the plastic material thicknesses T1 and T2 are in the range from about 3.8mm to about 4.0 mm. As will be appreciated by those skilled in the art, the plastic thicknesses T1 and T2 may vary depending on the particular application for which the blow-molded plastic structure 10 is being used.

Fourth embodiment

Fig. 13A to 13C show a part of a blow-molded plastic structure 10 according to a fourth embodiment of the present invention. The structure 10 includes a first outer portion 12 that is generally planar as described in other embodiments, and a second outer portion 14, the second outer portion 14 being generally spaced apart from the first outer portion 12. The first and second outer portions enclose a hollow inner portion 16 formed during the blow molding process. The fourth embodiment includes a pattern of structural reinforcing features in the form of tripod recesses 18 integrally formed in the second outer part 14 of the structure 10. Each recess 18 extends towards the first outer portion 12 of the structure. The depressions 18 are arranged in rows 22 and columns 24 in the second outer portion 14, and this pattern may be repeated over a substantial portion of the second outer portion 14 of the structure. As shown in fig. 13A, the rows 22 and columns 24 may be arranged such that each tripod recess 18 is closely adjacent to the other tripod recess 18 in the adjacent row 22 and column 24 over a substantial portion of the second outer part 14.

As shown in fig. 13A, in the fourth embodiment, all the recesses 18 in the row 22a are rotationally aligned in the same direction. The depressions 18 in adjacent rows 22b are rotationally aligned alternately 180 deg. from one to the next. All of the recesses 18 in row 22c are rotationally aligned in the same direction, but they are rotationally flipped 180 ° relative to the corresponding recesses 18 of row 22 a. All of the recesses 18 in row 22d are aligned in the same direction as the corresponding recesses 18 in row 22 b. The pattern repeats starting from the row below row 22 d.

With continued reference to fig. 13A, all of the recesses 18 in column 24a are rotationally aligned in the same direction. The depressions 18 in adjacent columns 24b are alternately rotationally aligned 180 deg. from one to the other. All of the recesses 18 in column 24c are rotationally aligned in the same direction, but they are rotationally flipped 180 ° relative to the corresponding recesses 18 in column 24 a. All of the recesses 18 in column 24d are aligned in the same direction as the corresponding recesses 18 in column 24 b. The pattern repeats starting with the column to the right of column 24 d.

As shown in fig. 13B-13C, each recess 18 is centered on a three-sided island 26 spaced from the first outer portion 12. Each depression 18 also includes dimples, shown as dimples 28a,28b and 28c, adjacent each side of the three-sided island 26. Thus, as shown, indentations 28a-c and islands 26 form the central portion of tripod recess 18 in second outer portion 14 of structure 10. In the fourth embodiment, the center-to-center spacing D5 between the dimples 28a-c in each depression 18 is in the range from about 11mm to about 14mm, and is preferably 12.5mm. The centerline of the tripodal recess 18 of each row 22a is spaced from the adjacent row 22b by a distance D9, the distance D9 being in the range from about 39.6mm to about 48.4mm, and preferably 44.0mm. Likewise, the tripodal concavity 18 of each column 24a is spaced from the adjacent column 24b by a distance D10, the distance D10 being in the range of from about 43.2mm to about 52.2mm, and preferably 48.0mm. The centerline spacing between adjacent recesses 18 in each row is about 86mm to about 106mm, and preferably 96mm. The centerline spacing between adjacent depressions 18 in each column is about 79mm to about 97mm, and preferably 88mm. The diagonal centerline spacing D11 is about 58.6mm to about 71.6mm and preferably 65.1mm.

As shown in fig. 13C, the structural reinforcement feature includes the interspersed regions 30 of the second outer portion 14, the interspersed regions 30 being disposed between the recesses 18. The interpenetration zone 30 has a height H1 (distance from the first outer portion 12 to the second outer portion 14), the height H1 being in the range from about 18.0mm to about 22.0mm and preferably 20.0mm. Within each dimple 28a-28c, the height H2 between the second outer portion 14 and the first outer portion 12 is in the range from about 5.4mm to about 6.6 mm. In a preferred embodiment, the height H2 is 6.0mm. Each dimple 28a-28c has a total depth (H1-H2), and preferably at least about 83% of the height H1. Additionally, within each indentation 28a-28c, the second outer portion 14 may be spaced apart from the first outer portion 12 of the blow-molded plastic structure or may contact the first outer portion 12, depending on the load applied to the structure 10. The three-sided islands 26 in the depressions 18 have a center height H3, with the center height H3 preferably being greater than 20% of the height H1 and less than about 1.3 times the height H2. The height H3 may range from about 7.2mm to about 8.8mm, and is preferably 8.0mm.

In a fourth embodiment, the plastic material thicknesses T1 and T2 are in the range from about 3.8mm to about 4.0 mm.

Fifth embodiment

Fig. 14A to 14B, 15A to 15B, 16 and 17A to 17E show a blow-molded plastic frame 10 of a portable shrinkable label according to a fifth embodiment of the present invention. The frame 10 includes a generally planar first outer portion 12 spaced from a generally planar second outer portion 14. The first and second outer portions enclose a hollow inner portion 16 formed during the blow molding process. The frame 10 includes a pattern of structural reinforcement features including a first recess 18a and a second recess 18b, the first recess 18a being integrally formed in the first outer portion 12 and the second recess 18b being formed in the second outer portion 14. Each first recess 18a extends inwardly from the first outer portion 12 towards an aligned second recess 18b in the second outer portion 14 of the structure, and each second recess 18b extends inwardly from the second outer portion 14 towards an aligned first recess 18a in the first outer portion 12.

The first and second recesses 18a, 18b are preferably arranged in rows 22 and columns 24 in the first and second outer portions 12, 14, and this pattern may be repeated over a substantial portion of the first and second outer portions 12, 14. The rows 22 and columns 24 are preferably arranged such that each first recess 18a is immediately adjacent to another first recess 18a in an adjacent row 22 and column 24 over a large area of the first outer portion 12, and such that each second recess 18b is immediately adjacent to another second recess 18b in an adjacent row 22 and column 24 over a large area of the second outer portion 14. The centerline spacing D13 between adjacent recesses 18a-18b in each row 22 is about 60mm to about 66mm, and preferably about 63mm. The centerline spacing D12 between adjacent recesses 18a-18b in each column 24 is about 47mm to about 53mm, and preferably about 5mm.

As shown in fig. 17A to 17E, at the center of the bottom of each of the first recess 18a and the second recess 18b is a three-arm surface, which is referred to herein as a bottom plate 36. Each base plate 36 includes three arms 28a, 28b, and 28c having rotational symmetry, with each arm rotated 120 ° from the other arms. Thus, the bottom plate 36 forms a central portion of each of the first and second recesses 18a, 18b in the first and second outer portions 12, 14 of the frame 10. In a preferred embodiment, the spacing D14 between the ends of the arms 28a-28c within each recess 18a-18b is in the range from about 11mm to about 14mm, and preferably about 12mm.

As shown in fig. 15A-15B, the structural reinforcement feature includes regions 30 interposed between the recesses 18a in the first outer portion 12 and between the recesses 18B in the second outer portion 14. As shown in fig. 17C and 17E, the height H1 (the distance from the first outer portion 12 to the second outer portion 14 within the penetration region 30) is in the range from about 13.7mm to about 20.3mm, and preferably about 17mm. As shown in fig. 17E, the height H4a between the first outer portion 12 and the bottom plate 36 within each recess 18a is in the range from about 7.5mm to about 11.5mm, and preferably about 9.5mm. Similarly, as shown in fig. 17C, the height H4b between the second outer portion 14 and the bottom plate 36 within each recess 18b is in the range from about 2.5mm to about 6.5mm, and preferably about 4.5mm. As also shown in fig. 17C and 17E, the height H5 between the floor 36 of each recess 18a and the floor 36 of the aligned recess 18b is in the range from about 2mm to about 5mm, and preferably about 3mm.

As shown in fig. 16, the thickness T of the plastic material ranges from about 2.0mm to about 4.0 mm.

Advantages over conventional structures

Easy to produce. Because the edges of the depressions 18a and 18b have a large radius of curvature (R), the structure 10 may be more easily removed from the blow-molding machine.

Strength increase. During production, the amount of plastic material (such as HDPE) provided to the mold must be adjusted to provide the optimum amount of material for stretching of the recess structure in the mold. The curved configuration of the depressions 18a and 18b described herein allows a higher amount of plastic material to be used throughout the structure 10, helping to ensure that the structural areas surrounding the depressions 18a and 18b are not too soft when stretched in the mold. In this way, sufficient strength can be maintained more uniformly across the top and bottom surfaces of the structure 10.

Defect rate reduction. Due to the large radius of curvature (R) of the depressions 18a and 18b, the material stretches in the mold to a depth that is less than typical of conventional blow-molded structures. Thus, the stretched area of the bottom surface of structure 10 is not too soft, thereby significantly reducing the defect rate caused by the low strength of the bottom surface.

Better performance. Because the depth of the depressions 18a and 18b is less than in conventional blow-molded structures, the bottom surface of the structure 10 may be thinner, which requires less material. Less material of the bottom surface allows for use in the top surface More material, without an overall increase per unit of material. This allows the top surface to be made thicker and thus stronger and more durable, which results in better physical properties, for example in impact and load tests.

Less material is required for production. In addition, because the depth of the depressions 18a and 18b is less than in conventional blow-molded structures, less material is required per unit to produce the structure 10 while maintaining at least the same strength as conventional structures.

The production time is reduced.Due to the depression structure, the wall thickness may be more uniform across the structure 10 than would be possible with a conventional blow-molded structure. This allows the manufacturer to more quickly and efficiently adjust and/or fine tune the operation of the blow molding machine of the structure 10 than would be possible with conventional structures. This reduces the idle time of the machine.

Three dimple depressions are supported.Because the recesses 18a and 18b having the three arms 28a, 28b, 28c may be more evenly distributed over the entire bottom surface of the structure 10, the material stretch in the mold may be reduced. While the four-arm recess embodiment may provide greater overall strength, the four-arm recess requires a higher stretch ratio, which requires more units of production material. Thus, from a materials standpoint, the three-arm recesses 18a and 18b of the preferred embodiment provide advantages over a four-arm design.

The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. Accordingly, the scope and range of the disclosed embodiments are indicated by the appended claims. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.

Claims (22)

1. A blow molded plastic structure having a hollow interior portion formed during a blow molding process, the blow molded plastic structure comprising:

a first outer portion;

a second outer portion spaced apart from the first outer portion, wherein the hollow inner portion is disposed between the first and second outer portions, and wherein a distance between the first and second outer portions is defined by a first height; and, a step of, in the first embodiment,

a structural reinforcement feature pattern integrally formed in the first and second outer portions, the structural reinforcement feature pattern comprising:

a plurality of first recesses extending from the first outer portion into the hollow inner portion, the first recesses being arranged in rows and columns, each first recess including a first base plate spaced apart from the first outer portion, the first base plate including a plurality of first arms, one or more of the first arms being rotated a first angle relative to an adjacent one of the first arms; and, a step of, in the first embodiment,

A plurality of second recesses extending from the second outer portion into the hollow inner portion, the second recesses being arranged in rows and columns, each second recess including a second floor spaced from the second outer portion, the second floor including a plurality of second arms, one or more of the second arms being rotated a second angle relative to an adjacent one of the second arms,

wherein the first floor of the first recess is aligned with the second floor of an adjacent second recess.

2. The blow molded plastic structure of claim 1, wherein the first plurality of arms comprises three first arms and the second plurality of arms comprises three second arms, the first angle being 120 ° and the second angle being 120 °.

3. The blow molded plastic structure of claim 1, wherein a center-to-center spacing between first depressions in each row of first depressions is greater than three times the first height and a center-to-center spacing between second depressions in each row of second depressions is greater than three times the first height.

4. The blow molded plastic structure of claim 1, wherein a center-to-center spacing between first depressions in each row of first depressions is about 63 millimeters and a center-to-center spacing between second depressions in each row of second depressions is about 63 millimeters.

5. The blow molded plastic structure of claim 1, wherein a center-to-center spacing between first depressions in each column of first depressions is greater than twice the first height and a center-to-center spacing between second depressions in each column of second depressions is greater than twice the first height.

6. The blow molded plastic structure of claim 1, wherein a center-to-center spacing between first depressions in each column of first depressions is about 50 millimeters and a center-to-center spacing between second depressions in each column of second depressions is about 50 millimeters.

7. The blow molded plastic structure of claim 1, wherein the first height is in a range of about 13.7 millimeters to about 20.3 millimeters.

8. The blow molded plastic structure of claim 1, wherein the first floor of each first recess is spaced from the first outer portion by a second height in the range of about 7.5 millimeters to 11.5 millimeters.

9. The blow molded plastic structure of claim 1, wherein the second floor of each second recess is spaced from the second outer portion by a third height in the range of about 2.5 millimeters to 6.5 millimeters.

10. The blow molded plastic structure of claim 1, wherein the first floor of each first recess is spaced from the second floor of an adjacent second recess by a fourth height, the fourth height being in a range of about 2 millimeters to 5 millimeters.

11. The blow molded plastic structure of claim 1, wherein each of the first arms in the first floor of each first recess is aligned with a respective one of the second arms in the second floor of an adjacent second recess.

12. The blow molded plastic structure of claim 1, comprising a portion of a frame of a portable, collapsible sign.

13. A blow molded plastic frame for a portable, collapsible sign, the blow molded plastic frame comprising:

a first outer portion of the frame;

a second outer portion of the frame spaced apart from the first outer portion, wherein a distance between the first outer portion and the second outer portion is defined by a first height;

a hollow interior portion disposed between the first exterior portion and the second exterior portion; and, a step of, in the first embodiment,

A structural reinforcement feature pattern integrally formed in the first and second outer portions, the structural reinforcement feature pattern comprising:

a plurality of first recesses extending from the first outer portion into the hollow inner portion, the first recesses being arranged in rows and columns, each first recess comprising a first base plate spaced apart from the first outer portion, the first base plate comprising three first arms having rotational symmetry, wherein each first arm rotates 120 ° from the other first arm; and

a plurality of second recesses extending from the second outer portion into the hollow inner portion, the second recesses being arranged in rows and columns, each second recess comprising a second base plate spaced apart from the second outer portion, the second base plate comprising three second arms having rotational symmetry, wherein each second arm rotates 120 ° from the other second arm;

wherein the first floor of the first recess is aligned with the second floor of an adjacent second recess.

14. The blow molded plastic frame of claim 13, wherein a center-to-center spacing between first depressions in each row of first depressions is greater than three times the first height and a center-to-center spacing between second depressions in each row of second depressions is greater than three times the first height.

15. The blow molded plastic frame of claim 13, wherein a center-to-center spacing between first depressions in each row of first depressions is about 63 millimeters and a center-to-center spacing between second depressions in each row of second depressions is about 63 millimeters.

16. The blow molded plastic frame of claim 13, wherein a center-to-center spacing between first depressions in each column of first depressions is greater than twice the first height and a center-to-center spacing between second depressions in each column of second depressions is greater than twice the first height.

17. The blow-molded plastic frame of claim 13, wherein a center-to-center spacing between first depressions in each column of first depressions is about 50 millimeters and a center-to-center spacing between second depressions in each column of second depressions is about 50 millimeters.

18. The blow molded plastic frame of claim 13, wherein the first height is in a range of about 13.7 millimeters to about 20.3 millimeters.

19. The blow molded plastic frame of claim 13, wherein the first floor of each first recess is spaced from the first outer portion by a second height in the range of about 7.5 millimeters to 11.5 millimeters.

20. The blow molded plastic frame of claim 13, wherein the second floor of each second recess is spaced from the second outer portion by a third height in the range of about 2.5 millimeters to 6.5 millimeters.

21. The blow molded plastic frame of claim 13, wherein the first floor of each first recess is spaced from the second floor of an adjacent second recess by a fourth height, the fourth height being in a range of about 2 millimeters to 5 millimeters.

22. The blow molded plastic frame of claim 13, wherein each of the first arms in the first floor of each first recess is aligned with a respective one of the second arms in the second floor of an adjacent second recess.