Two-piece structure including a blow-molded plastic portion

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to and the benefit of U.S. provisional patent application Ser. No. 60/579,590, filed Jun. 14, 2004. This application also claims priority to and the benefit of United States provisional patent application Ser. No. 60/579,338, filed Jun. 14, 2004. These applications are incorporated by reference in their entireties.

BACKGROUND

1. Field of the Invention

The present invention generally relates to blow-molded plastic structures and, in particular, to two-piece blow-molded plastic structures.

2. Description of Related Art

It is known to make a variety of structures from blow-molded plastic. For example, it is known to construct bases for portable basketball systems and table tops from blow-molded plastic. In particular, it is known to use blow-molded plastic to create table tops for utility-type tables. Utility tables are typically about six to eight feet in length and about two to three feet in width. Utility tables typically also include legs that are pivotally attached to the table top and the legs may be movable between a use position in which the legs extend outwardly from the table top and a storage position in which the legs are folded against the table top. Utility tables are often used in assembly halls, banquet halls, convention centers, hotels, schools, churches and other locations where large groups of people meet.

It is known to construct conventional utility tables from relatively heavy materials such as wood or metal, which may make the tables heavy and difficult to move. In particular, the table tops of many conventional utility tables are often made from fiber board, particle board, or plywood; and these known table tops may include a plastic or Formica-type surface laminated onto the upper surface of the table top to create a working surface. Disadvantageously, many of these conventional tables are not very strong and are unable to support a desired amount of weight. In order to increase the strength of these tables, thicker and heavier table tops are often used. Unfortunately, the thicker and heavier table tops further increase the weight of the tables. As a result, many conventional tables with wooden table tops are undesirably heavy, and two or more people are often required to move the tables. Further, heavier tables can increase shipping costs for manufacturers, retailers, and customers.

In order to decrease the weight of these conventional tables, the table tops can be constructed from relatively thin, light-weight materials. Disadvantageously, these lightweight table tops frequently require reinforcing members or other structural parts such as frames, railings, brackets and the like to strengthen the table top. These additional parts may increase the strength of the table top, but these additional parts also increase the weight of the table. In addition, these additional parts increase manufacturing costs and require additional time to assemble the table. Furthermore, these additional parts may have sharp edges that can injure the user's legs, arms or other body parts.

It is also known to construct table-tennis or “ping pong” tables from relatively heavy materials such as wood. In particular, many conventional table-tennis tables include a table top constructed of particle board or medium density fiberboard (“MDF”). Disadvantageously, many conventional table-tennis tables are not very strong and unable to support a large amount of weight. It is known to use thicker and heavier materials in order to increase the strength of these know table-tennis tables. This, however, may undesirably increase the weight of the table-tennis table and make the table more difficult to move and store. The additional weight may also increase the costs to ship and transport the table-tennis table.

The large size of conventional table-tennis tables may also make the tables more expensive to ship and transport. For example, conventional table-tennis tables are about nine feet in length (2.75 meters) and about five feet in width (1.5 meters). In addition, many conventional table-tennis tables are designed to be moved because most people are unable to dedicate a large area for playing ping-pong. Thus, many people desire to play ping-pong for a period of time in one area and then move the table-tennis table into a different area for storage. Because table-tennis tables are quite large, bulky and require a large amount of storage space, the tables are often stored in garages, on patios and in other areas that are more susceptible to various weather conditions such as heat, cold, sunlight, rain, snow and the like. Unfortunately, these weather conditions can often warp or otherwise damage conventional table-tennis tables.

SUMMARY

A need therefore exists for a structure that eliminates the above-described and/or other disadvantages and problems.

One aspect is a structure, such as a table-tennis top, that may include two or more components and the components may have different characteristics. Preferably the structure is designed and configured to maximize particular characteristics of the different components. For example, the characteristics of one component may include lightweight and the characteristics of another component may be high-strength and/or rigidity. Thus, the structure may be designed to maximize the lightweight characteristics of the one component and the high-strength characteristics of the other component.

Another aspect is a structure, such as a table-tennis top, that may include two or more components that are interconnected. Desirably the components have different characteristics and the components may be used to create a structure such as a table-tennis top. For example, the table-tennis top may include a first portion that is constructed from a lightweight material such as blow-molded plastic and a second portion that is constructed from a heavier material with a greater relative mass, density or weight than the blow-molded plastic. The blow-molded plastic portion and the increased mass portion may be connected to form at least a portion of the table-tennis top. For example, the increased mass portion may be connected to the blow-molded plastic portion so that either the increased mass portion and/or the blow-molded plastic portion form at least a portion of the playing surface. All or a portion of the increased mass portion may also be disposed within the blow-molded plastic portion, if desired.

Yet another aspect is a structure, such as a table-tennis top, that may be constructed from two or more components and at least one of the components is constructed from blow-molded plastic. The other components are preferably constructed from other materials and/or processes so that the components have different characteristics. Advantageously, the different characteristics of the components may be used to maximize particular capabilities of the components and/or minimize other features of the components.

Still another aspect is a structure, such as a table-tennis top, that includes a component or portion constructed from blow-molded plastic. Advantageously, the blow-molded plastic portion may allow a lightweight table-tennis top to be constructed. The blow-molded plastic portion may also be easily formed into a desired configuration, shape, size and design. In addition, the blow-molded plastic portion may be used to create a table-tennis top that is generally weather resistant and temperature insensitive, which may allow the table-tennis table to be used and/or stored in a wide variety of locations and environments. The blow-molded plastic portion may also create a table-tennis top that is durable, long-lasting, corrosion resistant, rust resistant and otherwise does not deteriorate over time. Accordingly, this may allow the table-tennis table to be used and/or stored outside, in a garage and the like. Further, because the blow-molded table-tennis top may be relatively strong, it can be used to support a relatively large amount of weight. Thus, the blow-molded table-tennis top may form a structural member of the table. The blow-molded table-tennis top may also be supported by a frame or other components, if desired.

The blow-molded plastic table-tennis top may be relatively strong because it may include two or more opposing walls or surfaces that are separated by a distance. The opposing surfaces are preferably separated by a generally constant distance so that the table-tennis top has generally uniform characteristics and the opposing walls may help create a high-strength, rigid structure. In addition, because a hollow interior portion may be formed during the blow-molding process, the table-tennis top may be lightweight. Thus, the table-tennis top can be both lightweight and strong.

Yet another aspect is a structure, such as a table-tennis top, that may include a blow-molded plastic portion and this portion may include one or more depressions, “tack-offs” or “kiss-offs.” The depressions, which can extend from one surface towards another surface, may be desirably sized and configured to increase the strength and/or rigidity of the structure. The depressions may extend from one surface and contact or engage an opposing surface, but the depressions do not have to contact or engage another surface. Advantageously, the depressions may be integrally formed during the blow-molding process as part of a unitary, one-piece structure. The blow-molding process may also allow other features to be integrally formed in the structure.

Still another aspect is a structure, such as a table-tennis top, that may include a blow-molded plastic component with thin outer walls, which may reduce the amount of plastic required to manufacture the component. This may save manufacturing costs and reduce the amount of resources required to construct the component. The thin outer walls may also allow the component to be cooled more quickly during the manufacturing process, which may increase manufacturing efficiency. In addition, the thin outer walls may reduce the weight of the blow-molded plastic component, which may decrease shipping costs and allow the structure to be more easily moved.

Another aspect is a table-tennis table that may include a first portion of a table-tennis top constructed from blow-molded plastic and including a hollow interior portion that is formed during the blow-molding process. The first portion of the table-tennis top preferably includes an upper portion and a lower portion, and the first portion of the table-tennis top may have a first set of characteristics. The table-tennis table may also include at least one leg assembly connected to the first portion of the table-tennis top; and a second portion of the table-tennis top that is attached to the first portion of the table-tennis top. The second portion preferably has a second set of characteristics that are different than the first set of characteristics of the first portion. The first set of characteristics of the first portion of the table-tennis top and the second set of characteristics of the second portion of the table-tennis top may be selected to create a table-tennis top with desired characteristics. For example, the second portion of the table-tennis top may have increased mass, rigidity and/or strength relative to the first portion of the table-tennis top.

Advantageously, the second portion of the table-tennis top may be attached to the upper portion of the first portion of the table-tennis top, and the second portion may create a least a portion of a playing surface of the table-tennis table. The second portion of the table-tennis top may also be attached to the lower portion of the first portion of the table-tennis top, and the first portion may create a least a portion of a playing surface of the table-tennis table. In addition, the second portion of the table-tennis top may be at least substantially disposed within the hollow interior portion of the first portion of the table-tennis top. If desired, the second portion of the table-tennis top may be constructed from acrylic or a laminated material. The second portion of the table-tennis top may also include multiple layers that are attached to the first portion of the table-tennis top. The second portion of the table-tennis top may cover substantially the entire upper portion of the first portion of the table-tennis top. Further, the second portion of the table-tennis top may be connected to the first portion of the table-tennis top by an adhesive layer or by a mechanical connection.

Still another aspect is a table-tennis table that may include a first portion of a table-tennis top constructed from relatively lightweight blow-molded plastic and including a hollow interior portion that is formed during the blow-molding process, the first portion of the table-tennis top including an upper portion and a lower portion. The table-tennis table may also include at least one leg assembly connected to the first portion of the table-tennis top; and a second portion of the table-tennis top attached to the first portion of the table-tennis top, the second portion having increased mass relative to the first portion of the table-tennis top to facilitate construction of a table-tennis top with desired characteristics.

Yet another aspect is a table-tennis table that may include a first portion of a table-tennis top constructed from relatively lightweight blow-molded plastic and including a hollow interior portion that is formed during the blow-molding process, the first portion of the table-tennis top including an upper portion and a lower portion. The table-tennis table may also include at least one leg assembly connected to the first portion of the table-tennis top; and a second portion of the table-tennis top at least substantially disposed within the first portion of the table-tennis top, the second portion having increased mass relative to the first portion of the table-tennis top to facilitate construction of a table-tennis top with desired characteristics.

A further aspect is a table that may include a first portion of a table top constructed from blow-molded plastic and including a hollow interior portion that is formed during the blow-molding process, the first portion of the table top including an upper portion and a lower portion, the first portion of the table top having a first set of characteristics. The table may also include at least one leg assembly connected to the first portion of the table top; and a second portion of the table top attached to the first portion of the table top, the second portion having a second set of characteristics that are different than the first set of characteristics of the first portion. The first set of characteristics of the first portion of the table top and the second set of characteristics of the second portion of the table top are preferably selected to create a table top with desired characteristics.

These and other aspects, features, and advantages of embodiments of the present invention will become more fully apparent from the following detailed description of preferred embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

The appended drawings contain figures of preferred embodiments to further clarify and illustrate the above and other aspects, advantages and features of the invention. It will be appreciated that these drawings depict only preferred embodiments of the invention and are not intended to limit its scope. The invention will be described and explained with additional specificity and detail through the use of the accompanying drawings in which:

FIG. 1 is an exploded, partial cross-sectional side view of an exemplary structure including a first portion and a second portion, illustrating the first portion separated from the second portion and the structure as a portion of a table-tennis table;

FIG. 2 is a partial cross-sectional side view of the structure shown in FIG. 1, illustrating the first portion connected to the second portion;

FIG. 3 is a partial cross-sectional side view of another exemplary structure including a first portion and a second portion, illustrating the first portion connected to the second portion and the structure as a portion of a table-tennis table; and

FIG. 4 is a partial cross-sectional side view of still another exemplary structure including a first portion and a second portion, illustrating the first portion disposed within the second portion and the structure as a portion of a table-tennis table.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

The present invention is generally directed towards a structure including at least a portion that is constructed from blow-molded plastic, such as a table-tennis top. The principles of the present invention, however, are not limited to table-tennis tables. It will be understood that, in light of the present disclosure, the exemplary embodiments disclosed herein can be successfully used in connection with other types of tables, furniture and structures.

To assist in the description of the table-tennis top, words such as top, bottom, front, rear, right and left may be used to describe the accompanying figures. It will be appreciated, however, that the table-tennis top can be located in a variety of desired positions. It will also be understood that the drawings are not intended to limit the present invention and the drawings are not necessarily drawn to scale. A detailed description of the table-tennis top now follows.

As shown in FIG. 1, an exemplary table-tennis top 2 may include a first portion 6 and a second portion 8. The first and second portions 6, 8 preferably have different characteristics because, for example, the portions may be constructed from different materials and/or different processes. That is, one portion may be lightweight and the other portion may be relatively heavier, denser or have increased mass. One portion may also have greater strength and/or rigidity compared to the other portion. It will be appreciated that the first and second portions 6, 8 may have any desirable differences in characteristics depending, for example, upon the type of table-tennis top 2. Advantageously, the characteristics of the first and second portions 6, 8 may be maximized to create a table-tennis top 2 with improved characteristics. Thus, as discussed in greater detail below, the characteristics of the first and second portions 6, 8 of the table-tennis top 2 may be maximized to create a table-tennis table with uniform playing properties such as a consistent bounce, lighter weight, lower cost, easier to transport, improved weather resistance, and the like. It will be appreciated that the table-tennis top 2 could have any desired properties, characteristics and the like, and the table-tennis top may have any number of portions, components and the like.

In greater detail, the first portion 6 of the table-tennis top 2 may be constructed from a material that is more rigid, stiff and/or less resilient that the second portion 8 of the table-tennis top. For example, the first portion of the table-tennis top 2 may be constructed from a material such as plastic. In particular, the first portion of the table-tennis top 2 may be constructed from acrylic because it is a relatively high-strength, rigid and stiff material. The second portion 8 of the table-tennis top 2 may be constructed from a material with different characteristics such blow-molded plastic. The blow-molded plastic second portion 8 may have lower strength, rigidity and/or stiffness than the first portion 6 of the table-tennis top 2.

Advantageously, the characteristics of the first and second portions 6, 8 may be selected to create an improved table-tennis top 2. For example, the second portion 8 may be constructed from blow-molded plastic because it may be used to create lightweight and relatively inexpensive portion of the table-tennis top 2. The second portion 8 may be constructed using high-density polyethylene because, for example, it may allow this portion of the table-tennis top 2 to be quickly and efficiently manufactured. The first portion 6 may be constructed from acrylic because it may provide an appropriate surface upon which the table-tennis or ping-pong ball may bounce. This may also allow the ping-pong ball to bounce in a consistent and uniform manner. Thus, the characteristics of the materials and/or processes used to create the first and second portions 6, 8 may create an improved table-tennis top 2.

It will be appreciated that the first and second portions 6, 8 could be created using any suitable materials and/or processes, and the first and second portions could have a variety of suitable characteristics. It will also be appreciated that while the accompanying figures and description describe the structure in connection with a table-tennis top 2, the structure could have other suitable configurations and uses. For example, a table top for a table such as a utility table, conference table, card table, personal table and the like could have similar aspects, features and/or construction as described in connection with the table-tennis top 2. Thus, it will be understood that the table-tennis top 2 is only an exemplary embodiment and other structures could be constructed in accordance with the present disclosure.

In greater detail, as shown in the accompanying figures, the first portion 6 of the table-tennis top 2 may include an upper surface 10 and a lower surface 12, and the second portion 8 may include an upper surface 14 and a lower surface 16. The first portion 6 is preferably securely connected to the second portion 8 to form at least a portion of the table-tennis top 2. For example, the first portion 6 may be connected to the second portion using an adhesive, such as disclosed in Assignee's co-pending U.S. patent application Ser. No. ______ (attorney docket no. 15499.621.1), which was filed on Jun. 13, 2005, or a mechanical interface or connection such as disclosed in Assignee's co-pending U.S. patent application Ser. No. ______ (attorney docket no. 15499.622.1), which was filed on Jun. 13, 2005, each of which are incorporated by reference in their entireties. It will be understood that the first and second portions 6, 8 may be connected using other suitable manners and processes.

As shown in FIGS. 1 and 2, the lower surface 12 of the first portion 6 is preferably connected to the upper surface 14 of the second portion 8 of the table-tennis top 2. It will be appreciated that the first portion 6 does not have to cover the entire second portion 8 and the first and second portions could be connected in any suitable configuration. For example, as shown in FIG. 3, the upper surface 10 of the first portion 6 could be attached to the lower surface 16 of the second portion 8. Preferably, the first and second portions 6, 8 are positioned to create a structure with the desired configuration and properties. Thus, for example, depending upon the intended use or design of the table-tennis top 2, the first and second portions 6, 8 could be connected in any suitable arrangement or configuration.

In particular, the table-tennis top 2 preferably includes an upper surface that facilitates playing table-tennis or ping-pong. For example, the table-tennis top 2 may have a generally rectangular playing surface that is about 274 centimeters (or about 9 feet) in length and about 152.5 centimeters (or about 5 feet) in width. The table-tennis top 2 is preferably positioned in a generally horizontal plane and about 76 centimeters (or about 2.5 feet) above a support surface, such as a floor, to allow a game to be played. The table-tennis top 2 may also include a net that divides the table into two generally equally-sized halves. If desired, the table-tennis top 2 may be moved between a collapsed position and a playing position. For instance, the table-tennis top 2 may include two sections that are pivotally connected to allow the table-tennis top to be moved between the collapsed and playing positions. The table-tennis top 2 may also have any other suitable dimensions, configuration and arrangements depending, for example, upon the intended use of the table-tennis top.

The table-tennis top 2 is preferably constructed so that the ping-pong ball bounces in a predictable, consistent and uniform manner. In particular, the first and second portions 6, 8 are preferably selected so that the table-tennis top 2 provides a generally uniform bounce of about 23 centimeters (or about 8.75 inches) when a standard table-tennis ball, which is typically constructed of celluloid or a similar plastic material with a diameter of about 40 millimeters and a weight of about 2.7 grams, is dropped from a height of about 30 centimeters (or about 12 inches) above the upper surface of the table-tennis top. It will be appreciated that the first and second portions 6, 8 may also be selected so that the ping-pong ball in other suitable manners. For example, the table-tennis top 2 may be constructed to provide a generally uniform bounce of about 21 to 25 centimeters when a standard table-tennis ball is dropped from a height of about 30 centimeters above the upper surface of the table top. Of course, if desired, the table-tennis top 2 may have other suitable characteristics.

Although not shown in the accompanying figures, one of ordinary skill in the art will understand that the table-tennis top 2 may be supported by one or more leg assemblies. Each of the leg assemblies may include one or more legs and the legs may be movable relative to the table-tennis top 2 to facilitate storage and/or transportation of the table-tennis table.

As shown in the accompanying figures, the upper surfaces 10, 14 and the lower surfaces 12, 16 of the first and second portions 6, 8, respectively, are preferably spaced apart by a distance. These surfaces are preferably separated by a generally constant distance so that the first and second portions 6, 8 may have generally uniform characteristics, but the upper and lower surfaces could be separated by any suitable distances. As shown in FIGS. 1-3, the second portion 8 may include one or more depressions 18, which are also know as tack-offs or kiss-offs. The depressions 18 may be sized and configured to increase the strength and/or rigidity of the second portion 8 of the table-tennis top 2. Advantageously, if the second portion 8 is constructed from blow-molded plastic, then the depressions 18 may be integrally formed as a unitary part of the second portion.

The depressions 18 are preferably located in the lower surface 16 of the second portion 8 of the table-tennis top 2 and the depressions preferably extend towards the upper surface 14 of the second portion. The ends of the depressions 18 may contact or engage the upper surface 14, or the ends of the depressions may be spaced from the upper surface. The depressions 18 may cover substantially all or just a portion of the lower surface 16 of the second portion 8 of the table-tennis top 2. It will be appreciated that depressions 18 may also be formed in the first portion 6 of the table-tennis top 2 and that depressions are not required.

The depressions 18 may be arranged into a predetermined pattern or array in order to increase the strength and structural integrity of the second portion 8 of the table-tennis top 2. In particular, the depressions 18 may be spaced closely together in a predetermined pattern such that the distance between the depressions is reduced. unsupported areas of the upper surface of the second portion 8 of the table-tennis top 2. In addition, reducing the distance between the depressions 18 may increase the structural integrity and strength of the second portion 8 of the table-tennis top 2. Thus, the depressions 18 can be closely spaced on the lower surface 16 of the second portion 8 of the table-tennis top 2 such that the depressions are separated by a reduced or a minimum distance in order to create a table-top component and/or table top with greater strength, structural integrity, and an upper surface with increased smoothness.

The depressions 18 may also be arranged in a predetermined pattern with a generally constant and uniform spacing so that the second portion 8 of the table-tennis top 2 has generally uniform characteristics. In particular, the depressions 18 may be arranged into a uniform pattern across the bottom surface 16 of second portion 8 of the table-tennis top 2 so that the strength, structural integrity and/or other characteristics are generally uniform. The depressions 18, however, need not be arranged in any particular pattern of any particular characteristics or design.

Additional details regarding the size, shape, and configuration of depressions 18 that may be suitable for use in connection with a table-tennis top 2 are disclosed in U.S. patent application Ser. No. 10/409,000, entitled HIGH-STRENGTH, LIGHTWEIGHT BLOW-MOLDED PLASTIC STRUCTURES, filed Apr. 8, 2003, which is incorporated by reference herein in its entirety.

As discussed above, the table-tennis top 2 may be constructed from blow-molded plastic. In particular, the second portion 8 of the table-tennis top 2 may be constructed from blow-molded plastic and it may include a hollow interior portion formed during the blow-molding process. As shown in FIG. 4, the hollow interior portion of the second portion 8 of the table-tennis top 2 may be filled with ballast 20 such as, sand, water, concrete, foam, or other suitable materials having appropriate characteristics. Advantageously, this may create a table-tennis top 2 in which the ping-pong ball bounces in a generally uniform manner. For example, the ballast 20 may increase the weight of the second portion 8 of the table-tennis top 2 and that may cause the ping-pong ball to bounce in a more consistent manner. In addition, if the second portion 8 of the table-tennis top 2 is at least partially filled with ballast 20, then the first portion 6 may not be used. Thus, the table-tennis top 2 may simply consist of the second portion 8 and the ballast 20. It will be appreciated, however, that the ballast 20 may be used in combination with the first portion 6 if desired. It will also be appreciated that the ballast 20 may consist of a heavier material, such as sand, or a lighter material, such as foam, depending, for example, upon the desired characteristics of the table-tennis top 2.

While the table-tennis top 2 has been shown and described in connection with first and second portions 6, 8, it will be appreciated that a table-tennis top may include any suitable number of portions. Additionally, as discussed above, it will be understood that the structure could have other suitable configuration other than as a table-tennis top 2. For example, a table top could be constructed using the first and second portions 6, 8 in a manner similar to that discussed above to create a table top with desired characteristics. Advantageously, the table top may have a variety of suitable configurations, such as rectangular, round, square and the like, and the table top may include one or more desired features, properties and/or characteristics. For instance, one portion of the table top may be constructed from blow-molded plastic and another portion of the table top may be constructed from other materials and/or processes, such as acrylic, that have different features, properties and/or characteristics. This may allow a lightweight table top to be constructed because of the blow-molded plastic portion and a very strong, smooth upper surface because of the acrylic portion. It will be understood that the various portions of the table top could be constructed from any materials and/or processes with desirable characteristics.

Although this invention has been described in terms of certain preferred embodiments, other embodiments apparent to those of ordinary skill in the art are also within the scope of this invention. Accordingly, the scope of the invention is intended to be defined only by the claims which follow.