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Publication numberUS3632147 A
Publication typeGrant
Publication dateJan 4, 1972
Filing dateApr 2, 1970
Priority dateApr 2, 1970
Publication numberUS 3632147 A, US 3632147A, US-A-3632147, US3632147 A, US3632147A
InventorsFinger Julie
Original AssigneeFinger Julie
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Modular frame structure and connector
US 3632147 A
Abstract
A modular frame structure and connector is provided in which the connector contains a plurality of pairs of diametrically opposed openings which are each female receptacles for receiving and holding a corresponding male plug. A first pair of these openings defines an axis of the connector. A first plurality of the pairs of openings are positioned around the center of the connector with the axes of these openings being coplanar. The central plane so defined is normal to the axis of the connector and substantially divides the connector into equal halves. A second plurality of pairs of openings is provided one end of which lies between the above-mentioned central plane and one of the axial pair of openings of the device. The other end of this plurality of openings lies between the central plane and the other axial opening. A plug is provided which has two ends, one of which is a male plug adapted to mate with the female openings in the connector. The other end of the plug is adapted to connect to the frame members.
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Description  (OCR text may contain errors)

United States Patent [7 21 Inventor Julie Finger 156 South Gardner Street, Los Angeles, Calif. 90036 [21] Appl. No. 25,218 [22] Filed Apr. 2, 1970 [45] Patented Jan. 4, 1972 [54] MODULAR FRAME STRUCTURE AND CONNECTOR 6 Claims, 6 Drawing Figs.

[52] U.S. Cl ..287/ 189.36, 52/665 [51] Int. Cl Fl6b 2/16 [50] Field of Search 46/29; 287/54 A, 54 C, 189.36 R, 53.5, 20.92 C, 189.36 F; 52/665, 648

[56] References Cited UNITED STATES PATENTS 2,709,318 5/1955 Benjamin 46/29 X 3,073,633 1/1963 Jeffs 287/54 A 2,044,588 6/1936 Moore ....287/l 89.36 R X 2,954,250 9/1960 Wing... 46/29 X FOREIGN PATENTS 477,946 19 1951 Canada v 46/29 498,484 12/1954 Italy 46/29 Primary Examiner-David J. Williamowsky Assistant ExaminerWayne L. Shedd Att0meyRonald W. Reagin ABSTRACT: A modular frame structure and connector is provided in which the connector contains a plurality of pairs of diametrically opposed openings which are each female receptacles for receiving and holding a corresponding male plug. A first pair of these openings defines an axis of the connector. A first plurality of the pairs of openings are positioned around the center of the connector with the axes of these openings being coplanar. The central plane so defined is normal to the axis of the connector and substantially divides the connector into equal halves. A second plurality of pairs of openings is provided one end of which lies between the abovementioned central plane and one of the axial pair of openings of the device. The other end of this plurality of openings lies between the central plane and the other axial opening. A plug is provided which has two ends, one of which is a male plug adapted to mate with the female openings in the connector. The other end of the plug is adapted to connect to the frame members.

Pmm'm 4m 316321147 SHEETI or 2 Fig.2

INVENTOR.

4h JUL IE F/NGEI? BY L4 MW? ATTORNEY 1 MODULAR FRAME STRUCTURE AND CONNECTOR BACKGROUND OF THE INVENTION The present invention relates to modular connectors and more particularly to a novel connector and system for constructing modular frame structures.

At shows, fairs and exhibits, it is customary for manufacturers, sales people or other people promoting a particular point of view to set up booths in which their goods are exhibited or their material is made available to the public or to people attending the function. Frequently, large numbers of exhibitors will be establishing many such booths in a large hall or even in a large outdoor field.

In its simplest form such a booth can be assembled by nailing together a framework of wood of suitable dimensions and draping cloth or other material over the framework to provide the walls. In a similar manner, shelves and platforms can be provided for displaying goods or for holding promotional materials. While the simplicity of this type of structure may be appealing, there are several serious drawbacks to its use. First, such booths are not as inexpensive as they might appear. For instance, the wood frame and material are usually cut on the site to fit its particular requirement and after the exhibit is over, which typically lasts only a few days at the most, the booth is torn down and the material which was used for the booth is no longer useful. Thus, the costs cannot be amortized over more than one use. Next, such exhibit halls usually have contracts with labor unions which provide that union members must be used to perform any construction in which pieces of wood are nailed together. Thus, the personnel staffing the booth cannot assemble and disassemble the booth, even if they have the necessary skill, but instead additional labor expenses must be incurred in both the erection and the removal of the booth.

Another disadvantage of such simple booths, perhaps less apparent than the economic disadvantages discussed above, is that such exhibits are frequently used to promote advanced goods or services having a high-technological content to a sophisticated, professional clientele. Exhibitors at such shows obviously wish to avoid a jerry-built, old fashioned county fair image for their booth and instead seek to establish in the minds of their clientele an image of being as advanced as their product or services.

Another problem with booths of the type described above is that they are obviously not very portable. Today it is common for an exhibitor to wish to have a display at many different exhibits which may be held in a relatively short period of time but at many widely scattered locations. However, even if a booth as described above could be configured to be useful at more than one location and even if it could be assembled and disassembled a number of times without substantial damage to the structure, the weight and bulk of the material would make it impractical to ship it from location to location, considering the value of the material. Thus, the exhibitor is faced with the dilemma of either paying high freight costs to ship relatively low-value material from location to location or taking the extra time and trouble to reacquire new material at each location.

It is thus seen that there is a definite need today for an exhibit booth which can be easily assembled, which can be easily configured into different structures to fit a particular require ment and which is sufficiently light that it can be easily transported from place to place.

OBJECTS OF THE INVENTION It is accordingly an object of the present invention to provide an improved means for constructing frame structures.

It is another object of the present invention to provide an improved connector for use in constructing frame structures.

It is yet another object of the present invention to provide an improved modular frame structure and connector which can be easily assembled into any desired configuration by persons having no particular training or skill in assembling such structures.

It is still another object of the present invention to provide an improved modular frame structure which can easily be disassembled, transported to another location and reassembled at minimum cost and effort.

BRIEF DESCRIPTION OF THE PRESENT INVENTION Briefly stated, and in accordance with the presently preferred embodiment of the invention, a connector is provided whose body is a polyhedron. The body includes a first pair of diametrically opposed openings the axis of which defines the axis of the body. A first plurality of pairs of diametrically opposed openings are positioned around the center of the body, with the axes of these openings all lying in a common plane which is normal to the axis of the body. This center plane thus divides the body into two substantially equal halves. A second plurality of pairs of diametrically opposed openings is also provided, with each of these pairs having their first openings positioned between the center plane mentioned above and one of the openings which defines the axis of the body. The second opening of the second plurality of pairs is positioned diametrically opposite the first openings and thus lies between the center plane and the other of the openings which defines the axis of the body. Each of the above-mentioned openings projects inwardly from the surface of the body towards its centers and each is a female receptacle adapted to mate with a corresponding complementary male plug. In the preferred embodiment, the openings are threaded with female threads to receive a correspondingly threaded male plug. Each of the surfaces of the polyhedron corresponds to a respective opening described above, with each surface being normal to the axis of its respective opening. A modular frame structure system is provided by using this connector in combination with plugs and frame members which are to be attached into the frame structure system. The plug has a first end which is a male member complementary to the openings in the connector and, as mentioned above, in the preferred embodiment is threaded. The second end of the plug is adapted to connect to the frame member in any suitable manner.

BRIEF DESCRIPTION OF THE DRAWINGS The attached drawings show the invention in detail and illustrate the advantages obtained by its use. In the different figures, the same reference numeral is used to indicate the same part or component.

FIG. I shows a perspective view of a connector in accordance with the presently preferred embodiment of the invention.

FIG. 2 shows an end view of the connector of FIG. 1.

FIG. 3 shows a side view of the connector of FIG. 1.

FIG. 4 shows a sectional view taken along the lines IV-IV of FIG. 3.

FIG. 5 shows a perspective view of a modular frame structure using the connector of FIGS. 1 through 4, and

FIG. 6 shows an exploded perspective view of a detail of FIG. 5 and illustrates how the combination of the connector, the plug and the frame member is used to construct a modular frame structure.

DETAILED DESCRIPTION OF THE DRAWINGS FIG. 1 shows a perspective view of a connector in accordance with the preferred embodiment of the present invention. As shown therein, connector 10 is a polyhedron body having a plurality of openings in its surface extending radially inwardly towards the center of the body. The surface of connector 10 is formed from a plurality of flat surfaces each corresponding to a respective opening in connector 10. Each of these surfaces is normal to the axis of its respective opening and thus gives connector 10 its polyhedron shape. As is shown in greater detail below, in the presently preferred embodiment of the invention, there are 22 of the openings and thus 22 surfaces.

Each of the openings in connector 10 is a female receptacle designed to receive and hold a corresponding male plug. In the presently preferred embodiment of the invention, and is as is shown in all of the Figures, the openings are threaded with female threads to receive a correspondingly threaded male plug member, shown in more detail in FIG. 6 below.

Continuing now the description of FIG. 1, for each opening in connector 10 there is a corresponding opening on the opposite side of connector 10. Thus, each such opening and its respective opposed opening forms a diametrically opposed pair of openings whose axis passes through the center of connector 10.

A main axis 12' of connector 10 is defined by the axis of a first opening 12a and its corresponding diametrically opposed opening 12b (not shown in FIG. 1). These openings are hereafter called the axial openings. Spaced around the center of connector 10, around the center of the polyhedron, are a plurality of openings 14a, 16a, 18a, 20a, 22a and 24a. Each of these openings has a corresponding paired diametrically opposed opening l4b, 16b, 18b, 20b, 22b and 24b, respectively (again not shown in FIG. 1 for clarity). The axes of these opposed pairs of openings, hereafter called the central openings, are coplanar, with this central plane passing through the center of connector 10 and being normal to the main axis 12' of connector 10. The angle between adjacent axes of the central openings is above 30.

In the preferred embodiment, the connector 10 is completed by four additional opposed pairs of openings. Two of these openings, 26a, and 28a are shown in FIG. 1. The axis of each of these pairs of openings also passes through the center of connector 10 and forms a 45 angle with both the axis 12 and the central plane of connector 10. The centers of openings 26a, 28a, 30a and 320 (these last two openings not shown in FIG. 1) thus form a plane parallel to the central plane and lying between that plane and axial opening 12a. The centers of the diametrically opposed openings 26b, 28b, 30b and 3212 (none of which are shown in FIG. 1) form a second plane parallel to the central plane and lying between that plane and axial opening 12b. These openings 26a and 26b, 28a and 28b, 30a and 30b, and 32a and 32b are hereafter called the intermediate openings.

FIG. 2 shows an end view of the connector 10 looking down the axis 12' and shows the axial opening 12a and the intermediate openings 262, 28a, 30a and 320. For clarity, no hidden lines are shown in FIG. 2 so none of the other openings appear in that view.

FIG. 3 shows a side view of the connector 10 and shows the main axis 12 and its corresponding diametrically opposed axial openings 12a and 12b. This view also shows the central openings 14b, 18a, 20a, 22a and 24a around the center of connector l and the intermediate openings 26a, 28a and 30a on one side of connector and the intermediate openings 26b, 30b and 32b on the other side of connector 10. For clarity, the other openings are not shown as hidden lines in this view.

FIG. 4 shows a sectional view taken along the line IVIV of FIG. 3. This view shows the axial opening 12a and the opposed pairs of central openings 14a and 14b, 16a and 16b, 18a and 18b, a and 20b, 22a and 22b, and 24a and 24b. Also, as shown therein, the axes of these openings pass through the center of connector 10, with the angular spacing between adjacent axes always being 30, since there are l 2 equally spaced openings.

FIGS. 1 through 4 illustrate the details of connector 10, As shown therein the connector includes an axial pair of diametrically opposed openings, six pairs of central openings whose axes are coplanar and uniformally radially spaced every 30 in this plane. This central plane is normal to the main axis of connector l0 and divides connector 10 into two substantially equal halves. The connector is completed by four pairs of intermediate openings whose axes also pass through the center of connector I0 and which form a 45 angle with both the central plane and the main axis of connector 10. The connector thus includes eleven pairs of diametrically opposed openings.

In each instance, the spacing between the two openings which form the pair is uniform. A spacing of three inches has been found to be quite satisfactory. The advantages of this uniform spacing will be more apparent when the description of FIGS. 5 and 6 below is considered.

FIG. 5 shows a perspective view of a portion of a modular frame structure which is constructed in accordance with the present invention. As shown therein, a plurality of connectors 10 such as were described in FIGS. I through 4 above are used to interconnect a plurality of orthogonal frame members 40 and diagonal frame members 42. Of course, the shown structure is purely representational of the invention and the connectors, orthogonal members and diagonal members can easily be constructed into any desired configuration. Also, the diagonal members 42 shown in FIG. 5 are connected into the intermediate openings of the connector 10 to provide either 45 diagonals or 30-60 diagonals.

FIG. 6 shows a perspective exploded view of the detail 44 of FIG. 5 and illustrates how the frame members 40 are connected to the connector 10. As shown therein, a plug 46 is provided which includes a first end 48 which is a complementary male member for the openings in connector 10. Since in the preferred embodiment, the openings are threaded, the ends 48 in FIG. 6 are shown having corresponding male threads. The plug 46 is then simply screwed into the openings in connector 10. The second end 50 of plug 46 is designed to attach to the frame member 40. Any suitable means for attaching plug 46 to the frame members 40 may be used. In the preferred embodiment, and as is shown in FIG. 6, the frame members 40 are hollow pipes and the end 50 of plug 46 is cylindrical in shape, having a diameter slightly less than the inside diameter of the frame member 40. A spring-loaded snap ball 52 is provided in the end 50 and a corresponding groove 54 is provided on the inner surface of frame member 40. To assemble, the spring-loaded ball 52 is simply depressed with the thumb and the plug is slid into the inside of frame member 40 until the ball 52 snaps out into the groove 54 under the urging of an internal spring (not shown in FIG. 6). Such springloaded snap balls are well known to those skilled in the art. If desired, other connecting means between plug 46 and frame member 40 could be used. For example, they could be provided with complementary threads, or in many applications, a simple friction fit would be acceptable.

FIG. 6 also shows a second type of plug 54 which may be used with the invention. Plug 54 is identical to plug 46 except that a shoulder 56 is provided near its center. When this type of plug is used, the groove inside the frame member 58 (not shown) is spaced at a sufficient distance from the end such that when the spring-loaded ball 60 engages the groove, the end of frame member 58 rests on shoulder 56. It has been found useful to use this type of plug on vertical frame members which may be under a substantial amount of compressive force, so that these forces do not cause the frame member to slip downwardly past the spring-loaded snap ball and into the connector 10.

FIG. 6 also shows details of a base member 62 which may be provided under the bottom row of connectors 10. As shown therein, the base 62 is a cylinder of suitable dimensions having a threaded member at its top to engage the bottom opening of connector 10.

From the above description of the invention, it will be appreciated that an infinite variety of modular frame structures can be constructed using only one form of connector, one or two forms of plugs and a few standard lengths of frame members. The connectors, plugs and frame members can be made from any desired material. For example, it has been found satisfactory to make the components from aluminum, magnesium, or a suitable plastic such as polypropylene. These materials are particularly suited for use with the invention because of their strength characteristics and light weight. They can be easily used to assemble a frame structure of any desired configuration which can then easily be disassembled. The components can then be readily transported to another location where any other desired frame structure can be assembled.

While the invention is thus disclosed and a particular preferred embodiment described, it is not intended that the invention be limited to this shown embodiment. lnstead, many modifications will occur to those having skill in the art which lie within the spirit and scope of the invention. Accordingly, it is intended that the invention be limited only by the appended claims.

What is claimed is:

l. A modular frame structure system comprising, in combination: a connector, a plurality of hollow frame members and a plurality of plugs;

i. said connector comprising a eluding:

a. a first axial pair of diametrically opposed openings, the

axis of which defines an axis for said body;

b. a first plurality of pairs of diametrically opposed openings, the axes of which all lie in a first plane, said first plane being normal to said axis of said body and dividing said body into two substantially equal halves; and

c. a second plurality of pairs of diametrically opposed openings, each of said pairs comprising a first opening and a second opening, the centers of said first openings defining a plane substantially parallel to said first plane and lying between said first plane and a first one of said axial pair of openings, the centers of said second openings defining a plane substantially parallel to said first plane and lying between said first plane and the other one of said axial pair of openings;

d. each of said openings projecting inwardly from the surthree dimensional body inface of said body towards the center of said body;

e. each of said openings being threaded with female threads adapted to mate with male threads on a corresponding complementary male plug;

2. said hollow frame member including a groove around its inner surface; and

3. said plug having a first end and a second end, said first end having male threads complementary to said female threads in said openings in said connector and being adapted to mate with said openings, and said second end being adapted to fit within said hollow frame members and including a spring-loaded snap ball which seats in said groove for attaching said plug to said frame member.

2. The combination of claim 1 in which the angle between the adjacent axes of said first plurality of pairs of openings in said connector is substantially 30.

3. The combination of claim 2 in which the distance between the first opening and the second opening of each pair of openings in said connector is substantially equal to that of every other pair of openings in said connector.

4. The combination of claim 3 in which the body of said connector is a polyhedron having a respective surface corresponding to each opening in said body, each of said surfaces being normal to the axis of its respective opening.

5. The combination of claim 4 in which the axes of said second plurality of pairs of openings each forms substantially a 45 angle with said first plane and the axis of said body.

6. The combination of said claim 5 in which said second end of said plug includes a shoulder for supporting the end of said frame member.

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Classifications
U.S. Classification403/171, 403/217, 52/665, 403/328, 403/176
International ClassificationA47F5/14, E04B1/19, F16B7/18
Cooperative ClassificationA47F5/14, F16B7/185, E04B2001/1927, E04B2001/196, E04B1/1906
European ClassificationE04B1/19B1, A47F5/14, F16B7/18C