U.S. patent number 3,777,675 [Application Number 05/274,096] was granted by the patent office on 1973-12-11 for folding table leg brace construction.
This patent grant is currently assigned to Amtab Manufacturing Co.. Invention is credited to Tadeusz J. Hanusiak.
United States Patent |
3,777,675 |
Hanusiak |
December 11, 1973 |
FOLDING TABLE LEG BRACE CONSTRUCTION
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.degree. 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.
Inventors: |
Hanusiak; Tadeusz J. (Chicago,
IL) |
Assignee: |
Amtab Manufacturing Co.
(Chicago, IL)
|
Family
ID: |
23046751 |
Appl.
No.: |
05/274,096 |
Filed: |
July 21, 1972 |
Current U.S.
Class: |
108/132;
108/81 |
Current CPC
Class: |
A47B
3/0912 (20130101) |
Current International
Class: |
A47B
3/00 (20060101); A47b 003/00 () |
Field of
Search: |
;108/81,82,132-135,160
;248/188.9 ;287/98,57R |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Zugel; Francis K.
Assistant Examiner: Finch; Glenn O.
Claims
What is desired to be secured by Letters Patent of the United
States is:
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.degree. 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.degree. 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.degree. 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.degree.
during said folding movement and assume a detented engagement with
one another at the end of said movement.
Description
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 U.S. 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 to enable 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 in the
arms. This it can do at positions 180.degree. 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 the bottom of the table top.
The positions being detented, there is a substantial locking in
either of these positions.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a folding table in erected
condition and having the folding leg and bracing 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 3--3 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, and a bracing structure 20 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.
The leg 14 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 29 is welded 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 engaged against the opposite
curved sides of the tubular member 24 and are clamped in position
by means of 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.degree. in order
to achieve these positions is acompanied by a 180.degree. 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.degree.. 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
10 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 20 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.
* * * * *