US3777675A

US3777675A - Folding table leg brace construction

Info

Publication number: US3777675A
Application number: US00274096A
Authority: US
Inventors: T Hanusiak
Original assignee: Amtab Manufacturing Corp
Current assignee: Amtab Manufacturing Corp
Priority date: 1972-07-21
Filing date: 1972-07-21
Publication date: 1973-12-11
Anticipated expiration: 1990-12-11

Abstract

A folding leg for a table top has a bracing structure which is comprised of a cylindrical tubular member and a pair of juxtaposed arcuate cross section arms resiliently clamped on a swivel to the opposite sides of the tubular member adjacent one end of said tubular member with the tubular member nesting in the concave surfaces of the arms, these latter surfaces facing one another. The arms have extensions which diverge so that the arms and their extensions together form a generally wishbone structure, the ends of the extensions opposite the arms being hingedly connected to said folding leg which is pivoted adjacent one end of the table top. The second end of the tubular member is pivoted to the bottom of the table top spaced inwardly from said one end. The wishbone structure and tubular member are swingable relative to one another and will detent in two positions 180* apart in one of which the folding leg is normal to the table top and in the other of which the folding leg is parallel with the table top. Either detent position can be overcome by manual force.

Description

United States Patent -1 1 Hanusiak FOLDING TABLE LEG BRACE CONSTRUCTION [75] Inventor: Tadeusz J. Hanusiak, Chicago, 111.

[73] Assignee: Amtab Manufacturing Co., Chicago,

Ill.

[22] Filed: July 21, 1972 [21] Appl. No.: 274,096

Primary ExaminerFrancis K. Zugel Assistant Examiner-Glenn O. Finch Attorney-J. Irving Silverman et a1.

[ Dec. 11, 1973 [57] ABSTRACT A folding leg for a table top has a bracing structure which is comprised of a cylindrical tubular member and a pair of juxtaposed arcuate cross section arms resiliently clamped on a swivel to the opposite sides of the tubular member adjacent one end of said tubular member with the tubular member nesting in the concave surfaces of the arms, these latter surfaces facing one another. The arms have extensions which diverge so that the arms and their extensions together form a generally wishbone structure, the ends of the extensions opposite the arms being hingedly connected to said folding leg which is pivoted adjacent one end of the table top. The second end of the tubular member is pivoted to the bottom of the table top spaced inwardly from said one end. The wishbone structure and tubular member are swingable relative to one another and will detent in two positions 180 apart in one of which the folding leg is normal to the table top and in the other of which the folding leg is parallel with the table top. Either detent position can be overcome by manual force.

9 Claims, 5 Drawing Figures 1 FOLDING TABLE LEG BRACE CONSTRUCTION BACKGROUND OF THE INVENTION The invention relates to folding tables generally and more particularly is concerned with a leg brace for a folding table.

The type of table with which the brace construction of the invention is concerned is a relatively rugged one, as opposed to the so-called bridge or tea table. The latter are normally subject only to occasional use and even in such use the wear and tear is not very great. Tables to be used in halls, at meetings, in hotels and the large'social functions are larger than bridge or tea tables and are subject to heavy use. The tables and their folding mechanisms must be durable and fool-proof.

Many persons will be required to set them up and collapse them so that the mechanism must operate easily and safely lock in both the erect and the folded conditions.

The principal characteristic of the invention is its great simplicity and economy without sacrificing strength, durability and effectiveness.

Examples of folding tables of the general type involved may be seen in US. Pat. Nos. 2,374,670'and 3,072,451. The invention herein comprises an improvement over these structures.

SUMMARY OF THE INVENTION The invention'is characterized by the provision of a folding leg and bracing structure two of which are adapted to be secured to the bottom of a table top at the opposite ends of the table top to support the same while erect and toenable the legs to be swung against the bottom of the table top parallel therewith when the table is collapsed.

Each of the legs is braced by a folding structure comprising a cylindrical tubular member and wishbone structure pivoted to one another and resiliently clamped together. The wishbone structure has a pair of parallel arms of arcuate cross section with the concave sides facing one another and the curved surface of the tubular member is matingly engaged between these arms at one end thereof, on a pivotal connection which includes means resiliently clamping the arms upon the tubular member. The cylindrical tubular member is pivotally mounted to the bottom of the table top at the end opposite its connection with the arms, while the arms have divergent extensions whose ends are pivoted to the leg.

The connection between the arms and the tubular member is a detented one but can be overcome by manually forcing the pivotal movement of the arms and tubular member one relative to the other. The tubular member then rides out of the'concave surfaces and swivels on the edges of the arms until it can once more seat inthe arms. This it can do at positions 180 apart in one of which the leg is at right angle to the table top and in the other of which'the leg is folded flat against thebottom of the table top. The positions being-detented, there is a substantial locking in either of these positions.

BRIEFDESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a folding'table in erected condition and having the folding leg andbracing structure embodying the invention installed thereon.

FIG. 2 is an end-on elevational view of the folding table of FIG. 1 with portions broken away.

FIG. 3 is a fragmentary sectional view taken generally along the line 33 of'FIG. 1 and in the indicated direction, also showing the bracing structure in the process of being folded to collapse the leg.

FIG. 4 is a fragmentary bottom plan view of the folding table but in this case the leg has been fully collapsed and is lying parallel with and against the bottom surface of the table top.

FIG. 5 is a detailed sectional view taken generally along the line 5-5 of FIG. 4 and in the indicated direction.

DESCRIPTION OF THE PREFERRED EMBODIMENT The invention herein is characterized by simplicity and efficiency and primarily resides in the bracing mechanism of the folding table.

The table is designated generally 10 and comprises a table top 12 of any suitable construction which is assumed to be made out of wood for the purposes of this description, although it could be metal. There is a pair of legs 14 and 16 which are preferably constructed of steel tubular members, each being secured at an end of the table 10 to the bottom surface 18 of the table top 12. Each leg is pivotally mounted in any suitable manner, an example of which will be explained, anda bracing structure20 according to the invention braces each leg in a manner which enables the legs to be folded flat against the bottom surface 18 of the table top 12 as will also be explained. These bracing structures are identical and hence only one need be described.

I The leg 1-4 comprises an upper bar 21 whose ends are pivotally secured to the bottom surface 18 of the table top 12 by pillow blocks 23 fastened in place in any suitable manner. Parallel standards 27 are welded to the central part of the upper bar 21 and a pedestal member 29iswelded'to the bottom ends of the standards 27.

The leg 14 is an integral member easily fabricated and is conventional. For the purposes of the invention it is preferred that there be a pair of spaced apart standards as a part of the leg 14. These enable the securement of the bracing structure 20 to the leg 14 as will be explained.

The bracing structure 20 is formed of two parts, a wishbone structure 22 and a cylindrical tubular member 24. The wishbone structure 22 is comprised of a pair of separately fabricated but identical members held in assembly by virtue of the method of fastening. Each member is an angled member formed as a relatively simple stamping. One part is arcuate in cross section and the other is straight with a slight bend at its end. These parts are called the'arms 26 and the extensions 28. The best view of the configuration of the arms is obtained in FIG. 5 which shows them to be arcuate in cross section with the concave surfaces facing one another. These surfaces are matingly engagedagainst the opposite curved sides of the tubular member 24 and are clamped in position by meansof a bolt '30 that freely passes through suitable perforations in the arms 26 and the tubular member 24. The bolt '30 is substantially longer than the total thickness of the arms 26 and tubular member 30'and has coiled springs '32 under its head and nut with suitable washers, the springs'being placed under compression when the bracing structure 20 is assembled.

The extensions 28 are relatively flat strips and diverge from the arms as shown, the tab ends 34 being pivotally pinned at 36 to the standards 27. These ends 34 are preferably bent to parallel one another.

The tubular member 24 is a straight cylindrical tube of circular cross section having its end 38 opposite the pivotal connection with the arms 26 pivotally connected at 40 to the brackets 42 which in turn are secured to the bottom surface 18 of the table top 12.

When the wishbone structure 22 is aligned with the tubular member 24, that is, with the arms 26 matingly engaging the opposite surfaces of the tubular member as shown in FIG. 5, the bracing structure 20 is in either one of two positions. if the leg 14 is erect, that is, at right angle to the table top 12, then the bracing structure 20 is in the position shown in FIGS. 1, 2 and 3. This position is characterized by the free end 44 of the tubular member 23 extending out from the arms 26 opposite the divergent extensions 28.

If the leg 14 is folded flat against the surface 18 then the bracing structure 20 is in the position shown in FIG. 4. This position is characterized by the free end 44 of the tubular member 24 extending out from the arms 26 in the same direction as the divergent extensions 28.

Both of the above described positions are detented because of the springs 32. The movement of the leg 14 through 90 in order to achieve these positions is acompanied by a 180 rotation of the wishbone structure 22 relative to the tubular member 24 as best seen in FIG. 3. Thus, assuming that the leg 14 is erect, pressure upon the bracing structure 20 as for example by manually pushing the same in the direction of the arrow 46 will force the relative rotation of the tubular member 24 and the arms'26 around the bolt 30. The bracing structure 20 will fold as shown by the phantom lines of FIG. 3. The tubular member 24 will ride out from between the arms 26, moving them apart against the compression of the springs 32 and thereafter rotate on the edges of the arms 26 until the tubular member 24 and wishbone structure 22 have rotated 180. At this time the tubular member 24 will once more seat between the arcuate surfaces of the arms 26, snapping into position and being forcibly held there once more by the springs 32.

This folding movement can easily be commenced by turning the table upside down and stepping on the bracing structure 20, the components being simple and rugged enough to permit of this without likelihood of damage to the mechanism. The reverse movement of the leg 14 from folded to erect condition can be achieved by grasping the pedestal structure 29 and pulling the same away from the surface 18 in a pivoting movement of the leg 14 around the pillow blocks 23. The distance of the pedestal structure 29 from the bolt 30 is quite great so that considerable leverage multiplication is achieved and the tubular member 24 and the wishbone structure 22 readily pivot back to the bracing condition of FIGS. 1, 2 and 3.

The bracing structure is formed of three simple parts, a bolt, nut and washers and a couple of springs. The wishbone structure 22 is comprised of two simple stampings and the tubular member 24 is a sraight conventional tube cut to length and drilled with two holes for the

pivotal connections

30 and 40. There is no intricate or expensive forming or welding required.

The leg 14 and bracing structure 20 may be manufactured for sale as a unit to be purchased by makers of tables or the like to assemble with furniture of their own design.

Note that in the movement of the leg from erect to folded position at least a portion of the bracing structure 20 will extend through the plane defined by the leg 14. The standards 27 are thus best spaced apart to permit this to occur.

The bracing structure, like the legs 14 and 16, is preferably made out of steel structural members. The legs and tubular member 24 can be fabricated from commercial steel or aluminum tubing welded or brazed.

Variations can be made in the details of the invention without departing from the spirit or scope thereof as defined in the appended claims.

What is desired to be secured by Letters Patent of the United States is:

l. A bracing structure for a collapsible table or the like article of furniture which includes a table top having a leg swingably mounted to fold from a vertical erect position to a collapsed position flat against the underside of the table top and back to the erect position, said bracing structure comprising A. a wishbone structure having a pair of parallel arms of arcuate cross section and the arms having divergent extensions at one end thereof, and means for pivotally connecting the outermost ends of the extensions of the leg between the ends of said leg,

B. a tubular member having means at one end thereof for pivotally connecting same to the underside of said table top at a point spaced from the mounting of said leg and having the other end pivotally connected to said arms, the concave surfaces of said arms facing one another and matingly engaged against opposite sides of said tubular member,

C. the pivotal connection of said tubular member and said arms including means resiliently clamping the arms against the tubular member in a detented engagement whereby to enable the wishbone structure and tubular member to be forced out of their detented engagement sufficient to enable limited rotation of one with respect to the other in erecting or collapsing said leg.

2. The structure as claimed in claim 1 in which the wishbone structure and tubular member are rotatable one relative to the other and there is detented engagement at opposite ends of said rotation.

3. The structure as claimed in claim 1 in combination with a leg having a central passageway, the said outermost ends of the extensions being connected to said leg straddling said passageway, a portion of the bracing structure adapted to enter said passageway during the collapsing of said leg.

4. The structure as claimed in claim 1 in which said pivotal connection of the tubular member and arms comprises a bolt passing through the same and having resilient compression means on said bolt.

5. The structure as claimed in claim 4 in which said compression means comprise a spring on each end of the bolt engaging against the respective arm.

6 The structure as claimed in claim 3 in which the upper end of said leg includes an upper part for so swingably attaching the leg to said table top, the lower end includes a pedestal portion, and there is a pair of spaced apart central standards between said pedestal portion and upper part, said central passageway being constituted by the space between said standards and said outermost ends of said extensions being connected to the respective standards.

7. The structure as claimed in claim 6 in which the wishbone structure and tubular member are rotatable one relative to the other 180 and there is a detented engagement at opposite ends of said rotation, the leg and bracing structure lying in substantially the same plane at one end of rotation when the leg is collapsed with said bracing structure disposed between said standards.

8. A collapsible table or the like article of furniture having a table top and at least one folding leg and bracing structure comprising, a leg having an upper part swingably connected to the underside of said table top and arranged when erect to be disposed at 90 relative to said table top, said leg having a lower pedestal part and a pair of vertical spaced apart standards between the upper and lower parts, a bracing structure extending from a location on said underside spaced from said leg to the spaced apart standards and being arranged at an angle to both the leg and the underside when the leg is erect, the bracing structure including a cylindrical tubular member and a wishbone structure, the wishbone structure including a pair of arms of arcuate cross section with the concave surfaces facing one another and pivotally connected to one end of said tubular member in a connection which resiliently clamps the arms to opposite sides of the tubular member in a detented mating engagement and the arms having divergent extensions the ends of which are respectively pivotally connected to said standards, the tubular member being pivotally connected at its opposite end to the underside of said table top at said location, the leg adapted to be collapsed by applying pressure against the bracing structure toward the table top to force the rotation of the wishbone structure and tubular member relative to one another around their pivotal connection out of their detented engagement, the bracing structure enabling the leg to move to a position parallel with and flat against the said underside, a portion of the bracing structure passing through the space between said standards during said movement and the bracing structure assuming a position lying substantially in the same plane as the leg when the leg is fully folded.

9. The structure as claimed in claim 8 in which the tubular member and wishbone structure rotate through substantially during said folding movement and assume a detented engagement with one another at the end of said movement.

Claims

1. A bracing structure for a collapsible table or the like article of furniture which includes a table top having a leg swingably mounted to fold from a vertical erect position to a collapsed position flat against the underside of the table top and back to the erect position, said bracing structure comprising A. a wishbone structure having a pair of parallel arms of arcuate cross section and the arms having divergent extensions at one end thereof, and means for pivotally connecting the outermost ends of the extensions of the leg between the ends of said leg, B. a tubular member having means at one end thereof for pivotally connecting same to the underside of said table top at a point spaced from the mounting of said leg and having the other end pivotally connected to said arms, the concave surfaces of said arms facing one another and matingly engaged against opposite sides of said tubular member, C. the pivotal connection of said tubular member and said arms including means resiliently clamping the arms against the tubular member in a detented engagement whereby to enable the wishbone structure and tubular member to be forced out of their detented engagement sufficient to enable limited rotation of one with respect to the other in erecting or collapsing said leg.

2. The structure as claimed in claim 1 in which the wishbone structure and tubular member are rotatable one relative to the other 180* and there is detented engagement at opposite ends of said rotation.

6. The structure as claimed in claim 3 in which the upper end of said leg includes an upper part for so swingably attaching the leg to said table top, the lower end includes a pedestal portion, and there is a pair of spaced apart central standards between said pedestal portion and upper part, said central passageway being constituted by the space between said standards and said outermost ends of said extensions being connected to the respective standards.

7. The structure as claimed in claim 6 in which the wishbone structure and tubular member are rotatable one relative to the other 180* and there is a detented engagement at opposite ends of said rotation, the leg and bracing structure lying in substantially the same plane at one end of rotation when the leg is collapsed with said bracing structure disposed between said standards.

8. A collapsible table or the like article of furniture having a table top and at least one folding leg and bracing structure comprising, a leg having an upper part swingably connected to the underside of said table top and arranged when erect to be disposed at 90* relative to said table top, said leg having a lower pedestal part and a pair of vertical spaced apart standards between the upper and lower parts, a bracing structure extending from a location on said underside spaced from said leg to the spaced apart standards and being arranged at an angle to both the leg and thE underside when the leg is erect, the bracing structure including a cylindrical tubular member and a wishbone structure, the wishbone structure including a pair of arms of arcuate cross section with the concave surfaces facing one another and pivotally connected to one end of said tubular member in a connection which resiliently clamps the arms to opposite sides of the tubular member in a detented mating engagement and the arms having divergent extensions the ends of which are respectively pivotally connected to said standards, the tubular member being pivotally connected at its opposite end to the underside of said table top at said location, the leg adapted to be collapsed by applying pressure against the bracing structure toward the table top to force the rotation of the wishbone structure and tubular member relative to one another around their pivotal connection out of their detented engagement, the bracing structure enabling the leg to move to a position parallel with and flat against the said underside, a portion of the bracing structure passing through the space between said standards during said movement and the bracing structure assuming a position lying substantially in the same plane as the leg when the leg is fully folded.

9. The structure as claimed in claim 8 in which the tubular member and wishbone structure rotate through substantially 180* during said folding movement and assume a detented engagement with one another at the end of said movement.