Information
-
Patent Grant
-
6508184
-
Patent Number
6,508,184
-
Date Filed
Thursday, January 25, 200124 years ago
-
Date Issued
Tuesday, January 21, 200322 years ago
-
Inventors
-
Original Assignees
-
Examiners
Agents
- Workman, Nydegger & Seeley
-
CPC
-
US Classifications
Field of Search
US
- 248 1881
- 108 121
- 108 125
- 108 127
- 108 129
- 108 156
- 108 160
- 108 901
-
International Classifications
-
Abstract
A lightweight folding table with legs that may be attached without a separate fixturing step is disclosed. Preferably, the table includes a table top having a working surface and a mounting surface, upon which the legs are attached. Fixturing mounts may be integrally formed with the table top by a process such as blow molding. The fixturing mounts may be configured to receive and hold independent mounting assemblies, each of which is pivotally attached to a leg. The fixturing mounts may have fixturing protrusions arranged so as to frictionally engage the mounting assemblies in such a manner that the mounting assemblies are held in place. An adhesive may then be applied to the mounting assemblies to provide a more permanent attachment, if desired. The adhesive may be allowed to set without using any external fixturing implements to hold the mounting assemblies in place.
Description
BACKGROUND
1. The Field of the Invention
The present invention is related to a utility table, and more particularly, to a lightweight folding table having legs attached in self-fixturing fashion.
2. Technical Background
Lightweight folding tables are indispensable for groups or organizations that have limited floor space usable for multiple purposes. For example, foldable utility tables can be placed in a pre-determined configuration to meet the space requirements of a school or community gymnasium, a church multi-purpose room, or a hotel conference meeting room. Afterward, the tables can be neatly stored away and the room used for a different purpose. Thus, lightweight folding tables allow a group or organization to maximize the efficiency and utility of a particular space.
Foldable utility tables can also provide an immediate temporary work space in a garage, tool shed, and the like. The portability and foldability of these utility tables allows a user to conveniently set up, take down, and store the table whenever and wherever the user chooses.
A major drawback with many lightweight folding tables of the prior art is their inherent size and bulkiness. Many such utility tables require two people to collapse and store the table after use. Moreover, some prior art lightweight folding tables are heavy enough to cause injury if dropped or mishandled. These unwieldy tables are usually made from hardwood, particle board, or similarly heavy materials. In an attempt to overcome this bulkiness problem, some prior art portable utility tables are formed of lighter-weight materials. However, many of these utility tables generally lack the sturdiness of the heavier-weight prior art utility tables.
Another disadvantage to many prior art utility tables is the means used for attaching the table legs or two or more support pedestals to the underside of the table. As will be appreciated, prior art table legs are typically attached to the table top using mechanical fasteners, such as threaded screws or bolts, that are drilled into the underside of the table top. This means of attachment may compromise the integrity of the table top, thereby making it weaker at the point of attachment between the table legs and the table top.
Weakening of the table top material is especially problematic if lightweight materials are used to construct the tabletop. If legs are independently attached, as with smaller folding tables such as card tables, the danger of deflection of the table top may be increased because each leg is subject to lateral, or sideways, forces in multiple directions. With smaller tables, members used to attach the legs to the table top must also be compact, and thus may not effectively spread forces against the leg over a large region of the table top. In effect, forces against a leg are concentrated in the small region where the leg and any attachment members are affixed to the table top. As a result, the table top may bend, or the leg may become dislodged from the attachment members.
Many lightweight prior art tables compensate for the weakness of the lightweight table top material by adding a frame of stronger material underneath the table top. Such frames are typically made of metal, and add considerably to the weight of the table, to the extent that the table may no longer reasonably be classified as a lightweight table. Furthermore, additional parts are required to attach the frame to the table top. Tables with separate frames typically have legs that are not independently attached. In effect, the legs are attached to a separate, common member, such as the frame, which is then attached to the table top. Hence, extra steps are required to attach the legs to the table top.
In addition, mechanical fasteners tend to increase the number of parts required for a table. If any significant amount of friction is anticipated between a metal fastener and a plastic part, a bushing, bearing, or similar device must be used to insulate the plastic part from wear. Thus, it is especially desirable to avoid the use of mechanical fasteners between metal and plastic parts.
Prior art methods for attaching legs typically also require several steps to complete the attachment. For example, with many prior art tables, each leg must first be positioned against the underside of the table. Then, the leg must be fixtured, or held in proper alignment with the contact surface on the table top while fasteners are applied.
Fixturing often involves the use of multiple machines, in the case of an automated process, because one machine must hold the leg and the table top together, while another machine completes the fastening process. In the case of human assembly, one person must often keep the leg and table top together while another applies the fastening method. If a single person holds the leg and table top together, he or she must attach the table top and leg together while holding them. Such a process is often difficult to carry out rapidly without making errors. Alternatively, extra implements, such as clamps, clips, temporary mechanical fasteners, and the like may be applied prior to fastening and then removed once fastening has been carried out.
The need to fixture the table and legs adds dramatically to the time required to assemble the table, as well as the amount of equipment and employees needed. Fixturing is especially problematic when mechanical fasteners are used, because mating surfaces, such as bolts, threaded openings, and the like must be precisely aligned. Added steps in the assembly process also increase the chances that a mistake will be made, and the table improperly constructed.
From the foregoing, it will be appreciated that it would be an advancement in the art to provide a lightweight folding table that is durable enough to withstand the increased wear and tear that portable utility tables are subjected to over long periods of time and sturdy enough to support varying sized loads that will be place on the table, while at the same time being light-weight enough to be easily set up and taken down.
It would be another advancement in the art to provide a lightweight folding table that does not require extra process steps, machinery, or personnel to carry out fixturing of the legs to the table top for attachment. It would be a further advancement in the art to provide a lightweight folding table having a leg or support pedestal attachment mechanism that does not require any mechanical fasteners attached to the table top.
Yet further, it would be an advancement in the art to provide a method and apparatus for attaching legs to a table top that would not require occupation of a great deal of mounting space, and that would permit independent attachment and folding of the legs. The method and apparatus could then be effectively used with smaller tables, such as card tables.
Such a lightweight folding table is disclosed and claimed herein.
BRIEF SUMMARY OF THE INVENTION
The present invention is directed to a novel lightweight folding table having legs that are independently attached to a table top, preferably without the use of a frame or any additional mechanical fasteners. The table top maybe constructed of a lightweight material, such as a plastic, and may be made from an inexpensive and rapid process, such as blow molding. In one presently preferred embodiment, the table top includes a mounting surface and a working surface formed opposite the mounting surface. Preferably, each leg is pivotally mounted on the table top so that the legs may be folded against the table top for storage and transportation of the table. Each leg may fold in a different direction so that no two legs overlap.
Brackets may be provided to attach the legs to the table top. More specifically, each leg may be pivotally attached to a bracket, and each bracket may, in turn, be rigidly affixed to the mounting surface. The brackets are preferably made from a comparatively stiff, strong material, such as a metal. Preferably, the brackets are shaped to distribute lateral stresses against the legs over a comparatively large portion of the mounting surface, so that deflection of the table top does not occur.
Other members may be attached between the brackets and the legs to provide additional stability and locking in the unfolded and/or folded positions. For example, a slotted member and a support strut may be attached between the leg and the bracket. A knob, wingnut, or other similar tightening device may be threaded through the slot and a suitable opening in the leg to enable a user to lock the leg in a desired orientation.
A fixturing mount is preferably formed in the mounting surface for each bracket. The fixturing mount may include one or more fixturing protrusions, formed integrally with the table top, that are positioned to keep the bracket in place. For example, a mounting shelf may enclose all of the legs, and may form a fixturing protrusion in all of the fixturing mounts. Each fixturing mount may also have additional fixturing protrusions in the form of a first abutment positioned to restrict motion of the bracket in one lateral direction (a direction parallel to the table top) and a second abutment positioned to restrict motion of the bracket in a second lateral direction.
Other fixturing protrusions outside the fixturing mounts may also be used. For example, an upraised portion, in the form of a centrally located plateau, may be formed on the mounting surface. Each leg may be arranged so as to lay flat against one side of the plateau when the table is in the folded configuration. A securing member may be formed near each side of the plateau, so that each folded leg is engaged between the plateau and a securing member.
The fixturing protrusions may thus provide an effective guide for assembly of the brackets with the table top. Furthermore, the fixturing protrusions may be configured to fixture the brackets to the mounting surface for attachment. For example, the abutments may be formed in close proximity to the mounting shelf so that the bracket is held between the abutments and the mounting shelfby friction. Similarly, the securing members mayhold the legs against the plateau. Thus, the brackets may be effectively held in place once they are assembled, so that no additional fixturing steps need be taken. Recesses may also be formed in the mounting shelf with gaps designed to engage tabs protruding from the brackets, to provide additional holding or fixturing force. The brackets may then be attached to the mounting surface by any chosen method.
The fixturing provided by the fixturing protrusions is ideal for use with adhesive attachment, because the adhesive may be allowed to set with no further necessary steps. Thus, although the present invention may provide fixturing for mechanical fasteners, the fixturing action of the present invention provides unique benefits when used with an adhesive. Additional features may be used to facilitate application and setting of the adhesive. For example, slots may be formed in the fixturing protrusions to accommodate the adhesive and hold it next to the brackets, so that a tighter bond is formed.
From the foregoing, it will be appreciated that the present invention provides a lightweight folding table that is inexpensive and easy to manufacture, and yet lightweight and durable. The present invention also provides a method of attaching independent legs to a table top through the use of self-fixturing retaining structures, or fixturing mounts. The fixturing mounts help reduce the time, machinery, and personnel required for assembly of a table.
Furthermore, the table top design of the present invention permits effective use of adhesives to replace conventional mechanical fasteners, so that the part count and assembly time are further reduced. The present invention facilitates independent attachment of the legs so that smaller tables may be easily produced without sacrificing sturdiness. The foregoing and other advantages and features of the present invention will become more filly apparent by examination of the following description of the presently preferred embodiments and appended claims, taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
To better understand the invention, a more particular description of the invention will be rendered by reference to the appended drawings. These drawings only provide information concerning typical embodiments of the invention and are not to be considered limiting of 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 a perspective view of one presently preferred embodiment of a lightweight folding table with independently attached legs;
FIG. 2
is a perspective view of the lightweight folding table of
FIG. 1
, depicting the mounting surface of the table top with attached mounting assemblies to hold the legs in place;
FIG. 3
is an enlarged perspective view of a mounting assembly suitable for the embodiment of
FIG. 1
, with an associated fixturing mount formed in the mounting surface of the table top;
FIG. 4
is an enlarged perspective view of the fixturing mount of
FIG. 3
with a bracket of the mounting assembly attached to the fixturing mount by an adhesive and by frictionally engaged tabs protruding from the bracket to corresponding gaps in the fixturing mount; and
FIG. 5
is an enlarged perspective view of an alternative embodiment of a fixturing mount suitable for the table of
FIG. 1
, with slots formed in the fixturing mount to receive the adhesive, in place of the tabs and gaps of the embodiment of FIG.
4
.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Reference is now made to the figures wherein like parts are referred to by like numerals throughout. With particular reference to
FIG. 1
, a lightweight folding table according to the present invention is generally designated at
10
. Although the method and apparatus of the present invention maybe beneficially utilized with a long, narrow table with linked or unitary sets of legs, particular application is envisioned for a smaller table with independently attached legs, as depicted in FIG.
1
.
A table top
12
of the table
10
is preferably situated at a height suitable for use by a person, and may have a working surface
14
suitable for use and a mounting surface
16
upon which legs
18
and their associated supports may be mounted. The working surface
14
may be textured, beveled, or otherwise formed to provide attractiveness and comfortable, easy use by a user. The table top
12
may be constructed of any suitable material, and may be made through any number of manufacturing processes. Preferably, the table top
12
is made from a lightweight material such as plastic, and is made through a simple process such as blow molding.
Through blow molding, the table top
12
may be made substantially hollow, such that structural strength is substantially retained while less material is used. A “substantially hollow” member is a member having an interior cavity occupying a majority of any major cross-section of the member, i.e., a cross-section through more than just a small corner of the member.
The legs
18
may be disposed perpendicular to the table top
12
to maintain the table top
12
at the proper height when the table
10
is in the unfolded configuration. Preferably, the legs
18
are made from a comparatively stiff material, such as a metal. The legs
18
may also be made hollow so as to retain structural strength while requiring less material and weight. Each of the legs
18
may have a proximal end
20
and a distal end
22
. Feet
24
may be attached at the distal ends
22
of the legs
18
to broaden the surface over which the weight of the table
10
rests and avoid damaging flooring underneath the table
10
. The feet
24
may thus be made of a comparatively soft material, such as a plastic or rubber.
Although the table
10
of
FIG. 1
has four legs
18
, any suitable number of legs
18
may be included, as suited to the geometry and normal use of the table
10
. The apparatus and method of the present invention provides special advantages for tables for which it is desirable to attach and fold each leg independently, such as card tables, folding dining tables, and similar circular or square-shaped tables.
Referring to
FIG. 2
, the mounting surface
16
of the table top
12
is shown. A mounting shelf
26
may be formed about the periphery of the mounting surface
16
. As depicted in
FIG. 2
, the mounting shelf
26
is simply a substantially vertical, inward-facing wall against which various components may be mounted. The mounting shelf
26
thus restricts motion of any part resting against it in an outward direction. Although the mounting shelf
26
is depicted as square in shape, it may take any straight-sided or curved shape desired. The mounting shelf
26
is preferably integrally formed with the mounting surface
16
. Other features may also be formed in the mounting surface
16
to restrict inward motion of parts attached to the mounting surface
16
. Examples of such features will be depicted in connection with subsequent figures.
The upraised nature of the mounting shelf
26
may create an indentation
27
inside the mounting shelf
26
, into which the legs
18
may compactly fold. A plateau
28
may be formed centrally within the indentation
27
, and may be substantially square in shape, as depicted in FIG.
2
. The plateau
28
may provide additional structural strength and stiffness for the center of the table top
12
, and may also provide a suitable barrier for registering other components of the table. Similarly, an outer edge
30
of the table top
12
may also be upraised to provide strength, stiffness, and comfort for a user of the table
10
.
Securing members
32
may also be formed in the mounting surface
16
, within the indentation
27
. Preferably, the securing members
32
are situated near the plateau
28
so as to act as a clamping mechanism for the legs
18
. The legs
18
may then be folded into engagement with the plateau
28
and the securing members
32
to reach a folded position
34
, shown in phantom. Each of the securing members
32
may have a lip (not shown) extending over the legs
18
in the folded position
34
to hold them in place. Alternatively, the securing members
32
may simply be positioned close enough to the plateau
28
that the securing members
32
frictionally engage the legs
18
against the plateau
28
.
“Frictional engagement” refers to a method of assembly in which assembled parts are held together by friction. The assembled parts effectively fit tightly enough together that forces of static friction tend resist their disassembly. Little deflection of the assembled parts need occur to produce frictional engagement.
Each of the legs
18
may be pivotally attached to the mounting surface
16
with a mounting assembly
36
. The mounting assemblies
36
are preferably oriented such that the legs
18
fold into the position
34
depicted in
FIG. 2
, i.e., parallel to the edges of the plateau
28
. The legs
18
may thus fold at an angle with respect to the flat sides of the mounting shelf
26
. Alternatively, the legs
18
may be made to fold against the mounting shelf
26
, and the securing members
32
may be positioned to secure the legs
18
against the mounting shelf
26
in the folded configuration.
Referring to
FIG. 3
, one possible mounting assembly
36
suitable for the table
10
is depicted. Preferably, a fixturing mount
38
is formed in the mounting surface
16
. The fixturing mount
38
is simply some portion of the mounting surface
16
with a geometry suitable for receiving and retaining the mounting assembly
36
. Preferably, the fixturing mount
38
includes upraised portions of the mounting surface
16
that serve to restrict motion of the mounting assembly
36
in a lateral direction, i.e., parallel to the table top
12
.
The mounting assembly
36
may comprise a number of members configured to hold one of the legs
18
in place, while permitting the leg
18
to fold as desired. A bracket
39
of the mounting assembly
36
may abut the mounting shelf
26
, and may be held in place by the fixturing mount
38
. The bracket
39
may be substantially L-shaped so as to conform to a corner of the mounting shelf
26
. The bracket
39
may have a first end
40
, an intermediate portion
41
, and a second end
42
.
Preferably, the bracket
39
is thin, so as to be lightweight, but tall enough to have a high stiffness against bending in a vertical direction. The bracket
39
is preferably sufficiently long, to distribute the pressure of the leg
18
relatively evenly along the mounting surface
16
. The bracket is preferably formed of a substantially stiff and strong material, such as a metal. A “substantially stiff” material is a material having a comparatively high modulus of elasticity, i.e., higher than most lightweight materials, such as plastics. Preferably, each bracket
39
of the table
10
is independent, i.e., a separate member from the other brackets, so that each bracket
39
may be attached separately and easily.
One of the legs
18
may be pivotally attached to the bracket
39
at a pivot point
43
, which may be formed using a suitable fastener such as a bolt, screw, rivet, shaft and locking pin, or the like. A support strut
44
may be connected between the leg
18
and the bracket
39
to provide additional support for the leg
18
, particularly in a direction parallel to the second end
42
of the bracket
39
. The support strut
44
may be connected to the bracket
39
at a first attachment point
46
, which may be formed by a fastener such as that used to form the pivot point
43
.
Preferably, the attachment point
46
is located on an extension
47
extending from the second end
42
of the bracket
39
in near-perpendicular fashion, so that the first attachment point
46
is coaxial with the pivot point
43
. The support strut
44
may then pivot together with the leg
18
to reach the folded position
34
. The support strut
44
may be rigidly attached to the leg
18
, near the proximal end
20
of the leg
18
, at a second attachment point
48
. The second attachment point
48
may also be created by a fastener such as that of the pivot point
43
, although the second attachment point
48
need not accommodate pivoting, since the support strut
44
may rotate with the leg
18
.
A slotted member
52
may also serve to connect the leg
18
to the bracket
39
, and may also enable locking of the leg
18
in a desired configuration. The slotted member
52
maybe pivotally attached to the bracket
39
at a first attachment point
54
. The first attachment point
54
is preferably positioned on an offset portion
56
of the bracket
39
, so that the slotted member
52
is angled to permit the leg
18
to fold into the folded position
34
, which is angled with respect to the mounting shelf
26
. Folding the leg
18
to an angled folded position
34
enables the leg
18
to avoid features of the fixturing mount
38
that may otherwise impede folding of the leg
18
.
A slot
58
in the slotted member
52
preferably engages a sliding member (not shown) on the second attachment point
48
, disposed on the opposite side of the leg
18
from the support strut
44
. The sliding member may take any form that provides sliding motion with respect to the slotted member
52
. Furthermore, the sliding member may comprise a fastener configured for locking by hand, such as a knob or wingnut. Thus, a user may lock the sliding member to fix the position of the leg
18
with respect to the slotted member
52
, thereby locking the leg
18
in the folded or unfolded configuration.
Alternatively, the sliding member may not be configured for tightening and locking by hand. Rather, the slot
58
may be shaped to capture the sliding member when the leg
18
is folded, when the leg
18
is unfolded, or in both configurations. For example, the slot
58
may have a larger opening (not shown) near the leg
18
so that when the leg
18
is fully unfolded, the sliding member falls into the larger opening and remains in place until a user applies pressure against the slotted member
52
to remove the sliding member from the larger opening.
When the leg
18
is locked in the unfolded configuration, as depicted in
FIG. 3
, the slotted member
52
may provide lateral support similar to that provided by the support strut
44
. Since the support strut
44
and the slotted member
52
provide support in substantially perpendicular lateral directions, the support strut
44
and the slotted member
52
combine to completely support the leg
18
against lateral motion.
The bracket
39
may be held in place by an adhesive
60
applied at various strategic points. The adhesive
60
may be of any suitable type, but is preferably a urethane-based substance selected to bond plastic to metal. The function of the adhesive
60
and the operation of the fixturing mounts
38
will now be described in greater detail.
Referring to
FIG. 4
, the fixturing mount
38
of
FIG. 3
is shown, without the leg
18
, support strut
44
, slotted member
52
, or their associated attachment members
43
,
46
,
48
, and
54
. The bracket
39
, alone, is installed in the fixturing mount
38
. The bracket
39
may generally have a first arm
66
extending between the first end
40
and the intermediate portion
41
, and a second arm
68
extending between the intermediate portion
41
and the second end
42
.
Preferably, the fixturing mount
38
has a number of features designed to help retain the bracket
39
. For example, a first abutment
70
and a second abutment
72
may be positioned in close proximity to the mounting shelf
26
. A first recess
74
, a second recess
76
, and a third recess
78
may also be formed directly in the mounting shelf
26
. Such features may be easily created through blow molding by simply creating opposing protrusions and recesses in the mold prior to the blow molding operation.
The first abutment
70
may operate with the mounting shelf
26
to create a first channel
80
, or a narrow opening between the first abutment
70
and the mounting shelf
26
. Similarly, the second abutment
72
and the mounting shelf
26
may be separated by a second channel
82
. Preferably, the first and second channels
80
,
82
are dimensioned to receive the bracket
39
on either side of the intermediate portion
41
.
Preferably, some force must be applied to the bracket
39
to slide the bracket
39
into engagement within the first and second channels
80
,
82
, so that a frictional engagement is formed. The required force is preferably large enough to keep the bracket
39
firmly seated in the fixturing mount
38
when the table top
12
is moved, but small enough to be applied by hand so that the bracket
39
may be manually inserted, if desired.
The first abutment
70
, as depicted in
FIG. 4
, provides support against motion of the bracket
39
in a direction parallel to the second end
42
of the bracket
39
, i.e., a direction perpendicular to the first channel
80
. Similarly, the second abutment
72
restrains the bracket
39
against movement in a direction perpendicular to the second channel
82
. In effect, since the first and second channels
80
,
82
are substantially perpendicular to each other, the first and second abutments
70
,
72
are positioned to restrict motion of the bracket
39
in any lateral direction. Motion perpendicular to the mounting surface
16
may only be accomplished by overcoming the frictional engagement of the first and second abutments
70
,
72
.
The first recess
74
, the second recess
76
, and the third recess
78
may have a first gap
84
, a second gap
86
, and a third gap
88
, respectively. A first tab
100
, a second tab
102
, and a third tab
104
may then be inserted into the gaps
84
,
86
,
88
, respectively. The first tab
100
, for example, may simply be an extension of the first end
40
of the bracket
39
. The second tab
102
may be formed by making three perpendicular cuts in the intermediate portion
41
of the bracket
39
and bending the material between the cuts to a roughly perpendicular angle to the middle portion
41
. Thus, an opening
106
is formed, and the second tab
102
may extend from the opening to engage the second gap
86
. Similarly, an opening
108
may be formed in the second end
42
, and the material bent outward to form the third tab
104
, which may then engage the third gap
88
.
The gaps
84
,
86
,
88
and their associated tabs
100
,
102
,
104
may also act to more firmly seat that the bracket
39
within the fixturing mount
38
. Each of the tabs
100
,
102
,
104
resists bracket motion in a direction perpendicular to itself. Thus, the bracket
39
may be more resistant to lateral motion with the use of the tabs
100
,
102
,
104
. In addition, the gaps
84
,
86
,
88
and the tabs
100
,
102
,
104
may be dimensioned to frictionally engage one another, so as to provide resistance against withdrawal of the bracket
39
from the fixturing mount
38
in a direction perpendicular to the mounting surface
16
. The tabs
100
,
102
,
104
may also have curved terminal portions tending to grip interior surfaces of the recesses
74
,
76
,
78
to further keep the bracket
39
in place.
The securing member
32
that holds the leg
18
attached to the bracket
39
may provide additional support for the bracket
39
. In effect, the securing members
32
maintains the leg
18
in one rotational orientation when the leg
18
is in the folded position
34
. Consequently, any force tending to rotate the bracket
39
within the plane of the mounting surface
16
will be effectively resisted by the leg
18
because it is secured by the securing member
32
. The securing member
32
may also frictionally engage the leg
18
to support the bracket
39
against removal from the fixturing mount
38
in a direction perpendicular to the table top
12
.
Assembly of a leg
18
with the table top
12
may then be carried out without any extra process steps, personnel, or equipment to fixture the bracket
39
during attachment. “Fixturing,” as used herein, refers to the process of holding two parts together so that they can be more permanently attached. Since the bracket
39
is held comparatively firmly by the fixturing mount
38
, the table
10
is effectively “self-fixturing.”
Self-fixturing may be provided through the use of fixturing protrusions of the mounting surface
16
that are easily created through processes such as blow molding. The “fixturing protrusions” include any feature formed in the mounting surface
16
that tends to keep a mounting assembly
36
properly positioned for permanent attachment. In the embodiments depicted in
FIGS. 2
,
3
, and
4
, the fixturing protrusions include the mounting shelf
26
, the plateau
28
, the securing members
32
, the first abutment
70
, and the second abutment
72
. In effect, one process step is eliminated through the unique design of the mounting surface
16
including the fixturing protrusions
26
,
28
,
32
,
70
, and
72
.
Thus, assembly of a leg
18
to the table top
12
may be rapidly and easily carried out. For example, the leg
18
, bracket
39
, support strut
44
, and slotted member
52
may be assembled as depicted in FIG.
3
through the use of the various attachment members
43
,
46
,
48
, and
54
to form the mounting assembly
36
. The mounting assembly
36
may then be inserted into the fixturing mount
38
by aligning the bracket
39
with the first and second channels
80
,
82
and applying force to the bracket
39
to seat the bracket
39
firmly within the fixturing mount
38
.
The mounting assembly
36
may be inserted into the fixturing mount
38
with the leg
18
in the folded or unfolded configuration. If the leg
18
is folded during insertion, the leg
18
may be pushed into engagement with the securing member
32
and the plateau
28
simultaneously with insertion of the mounting assembly
36
into the fixturing mount
38
. If the leg
18
is unfolded during insertion, it may subsequently be folded into the folded position
34
to engage the securing member
32
and the plateau
28
. In either case, engagement of the leg
18
by the securing member
32
and plateau
28
may help fixture the bracket
39
.
After the mounting assembly
36
and the leg
18
are fully engaged, the bracket
39
is fully fixtured and ready for attachment to the mounting surface
16
by any desired method. Preferably, the bracket
39
is attached to the fixturing mount
38
. Mechanical fasteners may be utilized if desired. The self-fixturing properties of the bracket
39
and the fixturing mount
38
may facilitate application of mechanical fasteners.
“Mechanical fasteners,” as referred to herein, are independent solid devices used to attach two or more parts together. For example, bolts, nuts, screws, clips, clamps, rivets, and pins are all mechanical fasteners. Chemical adhesives, welds, and the like are not mechanical fasteners.
The self-fixturing properties of the table
10
may provide great benefits in combination with adhesive fastening methods. The adhesive
60
maybe applied at any comparatively tight interface between the bracket
39
and the fixturing mount
38
. As depicted in
FIGS. 3 and 4
, the adhesive
60
may, as one example, be applied at the first channel
80
, the second channel
82
, the first gap
84
, the second gap
86
, and the third gap
88
. Since the bracket
39
and the fixturing mount
38
are comparatively tightly assembled at these points, the adhesive
60
may effectively cap the bracket
39
against withdrawal of the bracket
39
in a direction perpendicular to the table top
12
.
The adhesive
60
may be applied by any desired method. If plastic is used to form the table top
12
, the plastic of the fixturing mount
38
maybe flame treated before application of the adhesive
60
to improve the bonding strength of the adhesive
60
to the table top
12
. The bracket
39
may similarly be coated or otherwise treated to improve the bonding strength of the adhesive
60
. The adhesive
60
may be applied by a brush, sprayer, dropper, or any other suitable applicator. Only a matter of seconds is required to apply the adhesive
60
over the channels
80
,
82
and gaps
84
,
86
,
88
.
Once the adhesive
60
is applied, it may simply be left to dry for a selected period of time, determined by the type of adhesive
60
used. Since the table
10
is self-fixturing, no other implements need be used to hold the mounting assembly
36
in position. Thus, multiple tables
10
maybe made, stacked in the folded configuration, and prepared for shipment even while the adhesive
60
is setting. The table
10
may even be transported while the adhesive
60
is setting. Engagement of the legs
18
by the securing members
32
ensures that the mounting assemblies
36
will not be dislodged from the fixturing mounts
38
when the table
10
is picked up by a user grasping one of the legs
18
in the folded position
34
, even if the adhesive
60
has not finished setting.
Although the tabs
100
,
102
,
104
and engaging gaps
82
,
84
,
86
may help fix the bracket
39
in place, as described above, they are not required features of the fixturing mount
38
. The first and second abutments
70
,
72
may provide sufficient gripping force to retain the bracket
39
against the mounting shelf
26
without the use of additional features. Alternatively, different features may be added to enhance the frictional engagement of the bracket
39
within the fixturing mount
38
, or to improve bonding strength of adhesives used.
Referring to
FIG. 5
, an alternative embodiment of a table
120
with a fixturing mount within the scope of the present invention is shown. The bracket
39
, the first abutment
70
, and the second abutment
72
are all substantially as depicted in FIG.
4
. However, for the embodiment of
FIG. 5
, the recesses
74
,
76
,
78
, the gaps
84
,
86
,
88
, the tabs
100
,
102
,
104
, and the openings
106
,
108
have been omitted. The first and second abutments
70
,
72
may be dimensioned such that the first and second channels
80
,
82
are tight enough to hold the bracket
39
in place without the addition of the tabs
100
,
102
,
104
.
In place of the recesses
74
,
76
,
78
, slots
121
,
122
,
124
,
126
have been formed in the mounting shelf
26
proximate the first end
40
, the intermediate portion
41
, the second end
42
, and between the first end
40
and the intermediate portion
41
. The slots
121
,
122
,
124
,
126
may be dimensioned to suit the viscosity of the adhesive
60
, so that the adhesive
60
may readily flow into the slots
121
,
122
,
124
,
126
. The slots
121
,
122
,
124
,
126
thus effectively provide a channel through which the adhesive
60
may flow to reach the side of the bracket
39
. Preferably, the slots
121
,
122
,
124
,
126
are also dimensioned to keep the adhesive from flowing away from the bracket
39
before setting. As a result, a larger bonding surface is created between the mounting shelf
26
and the bracket
39
, and the bracket
39
is more tightly attached to the mounting shelf
26
.
The slots
121
,
122
,
124
,
126
may be omitted or reconfigured as desired. For example, slots may be formed in the bracket
39
, the first abutment
70
, the second abutment
72
, or some combination thereof, rather than in the mounting shelf
26
. Different-shaped openings may be formed in the mounting shelf
26
, the abutments
70
,
72
, or the bracket
39
to accommodate the adhesive
60
.
In the alternative, the first and second channels
80
,
82
may simply be dimensioned to grip the bracket
39
with less of the adhesive
60
, or with no adhesive or other attachment method. If no attachment method is used to attach the mounting assembly
36
to the fixturing mount
38
, aside from the frictional engagement of the fixturing protrusions
26
,
70
,
72
of the fixturing mount
38
, the table
10
is not only self-fixturing, but also self-attaching.
The number of steps required for assembly is then reduced to one: the mounting assembly
36
must simply be properly positioned within the fixturing mount
38
. The mounting assembly
36
need not be permanently attached by a separate step, and the mounting assembly
36
need not be fixtured for permanent attachment. Thus, configurations in which no adhesive
60
is used may enable the table
120
or the table
10
to be manufactured in the simplest possible way.
Numerous other configurations are possible for the lightweight folding table provided by the present invention. The fixturing mounts
38
maybe located in any number of positions on the mounting surface
16
at which it would be desirable to attach a leg
18
. Similarly, any configuration of fixturing protrusions, within and outside the fixturing mounts
38
, may be used to effect self-fixturing. Similarly, the mounting assemblies
36
may take any form suitable for assembly with the mounting surfaces
16
of the present invention.
Many of the problems associated with prior art lightweight folding tables are addressed by the teachings of the present invention. From the above discussion, it will be appreciated that the present invention provides a novel lightweight folding table having legs that can be rapidly and easily attached to the table top with a minimum of machinery and personnel. The lightweight folding table may be constructed without a frame, so that each leg may independently be attached directly to the table top.
The present invention also provides novel fixturing mounts and mounting assemblies that may be assembled and permanently attached without a separate fixturing step. The fixturing mounts and mounting assemblies may also be permanently attached together without the use of mechanical fasteners. The present invention also provides novel systems and methods for attaching legs to a table top with an adhesive.
It should be appreciated that the apparatus of the present invention is capable of being incorporated in the form of a variety of embodiments, only a few of which have been illustrated and described above. The invention may be embodied in other forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.
Claims
- 1. A lightweight folding table, comprising:a tabletop comprising a working surface and a mounting surface disposed opposite the working surface; a plurality of legs independently arranged in supportable relation to the tabletop; a plurality of brackets secured to the mounting surface, each bracket of the plurality of brackets being configured to provide pivotal coupling between a leg of the plurality of legs and the tabletop; and wherein the mounting surface comprises a plurality of fixturing mounts, each of which is configured to receive a bracket from the plurality of brackets during attachment of the bracket to the mounting surface and wherein the fixturing mounts are configured to restrain motion of the brackets in any lateral direction.
- 2. The lightweight folding table of claim 1, wherein the tabletop is substantially hollow and is constructed of a plastic material formed by blow molding.
- 3. The lightweight folding table of claim 1, wherein the plurality of legs comprises at least three legs.
- 4. The lightweight folding table of claim 1, wherein each bracket of the plulraity of brackets are attached to the mounting surface without mechanical fasteners.
- 5. The lightweight folding table of claim 4, wherein the brackets are attached to the mounting surface by an adhesive applied between the brackets and the mounting surface.
- 6. The lightweight folding table of claim 5, wherein the fixturing mounts comprise a plurality of slots formed in the fixturing mounts, the slots being configured to receive the adhesive and to hold the adhesive against the brackets.
- 7. A lightweight folding table, comprising:a tabletop comprising a working surface and a mounting surface disposed opposite the working surface; a plurality of legs independently arranged in supportable relation to the tabletop; a plurality of brackets secured to the mounting surface, each bracket of the plurality of brackets being configured to provide pivotal coupling between a leg of the plurality of legs and the tabletop; and wherein the mounting surface comprises a plurality of fixturing mounts, each of which is configured to receive a bracket from the plurality of brackets during attachment of the bracket to the mounting surface and wherein each of the fixturing mounts comprises a plurality of fixturing protrusions positioned to restrain motion of a bracket from the plurality of brackets in a direction parallel to the table top.
- 8. The lightweight folding table of claim 7, wherein each bracket is further configured to be slidable in a direction substantially perpendicular to the table top to engage the fixturing protrusions.
- 9. A lightweight folding table, comprising:a tabletop comprising a working surface and a mounting surface disposed opposite the working surface; a plurality of legs independently arranged in supportable relation to the tabletop; a plurality of brackets secured to the mounting surface, each bracket of the plurality of brackets being configured to provide pivotal coupling between a leg of the plurality of legs and the tabletop; and wherein the mounting surface comprises a plurality of fixturing mounts, each of which is configured to receive a bracket from the plurality of brackets during attachment of the bracket to the mounting surface and wherein each of the fixturing mounts comprises at least a first gap, and wherein each of the brackets comprises at least a first tab protruding from the bracket, the first tab being configured to be engageable within the first gap.
- 10. A lightweight folding table, comprising:a tabletop comprising a working surface and a mounting surface disposed opposite the working surface; a plurality of legs independently arranged in supportable relation to the tabletop; a plurality of brackets secured to the mounting surface, each bracket being configured to pivotally attach a leg of the plurality of legs to the tabletop; and wherein the mounting surface comprises a plurality of fixturing protrusions configured to restrict lateral motion of the brackets.
- 11. The lightweight folding table of claim 10, wherein the plurality of fixturing protrusions further comprises a mounting shelf disposed proximate an outer edge of the mounting surface and positioned to restrict motion of each of the plurality of brackets toward the outer edge.
- 12. The lightweight folding table of claim 11, wherein the plurality of fixturing protrusions further comprises a plurality of abutments positioned proximate the mounting shelf, so as to restrict motion of each of the plurality of brackets away from the outer edge.
- 13. The lightweight folding table of claim 12, wherein the plurality of fixturing protrusions further comprises a securing member configured to engage one of the plurality of legs in a folded position of the leg, so as to restrain lateral motion of the leg.
- 14. The lightweight folding table of claim 11, wherein the mounting shelf further comprises at least a first gap corresponding to each bracket, each first gap having a narrow opening, and wherein each bracket comprises at least a first tab protruding from the bracket, the first tab being configured to be frictionally engageable within the narrow opening of the first gap to hold the bracket in place against the mounting shelf.
- 15. The lightweight folding table of claim 10, wherein each bracket is secured to the mounting surface by an adhesive applied between the bracket and one or more of the plurality of fixturing protrusions.
- 16. The lightweight folding table of claim 10, wherein the plurality of legs comprises at least three legs.
- 17. The lightweight folding table of claim 16, wherein the plurality of legs comprises four legs.
- 18. The lightweight folding table of claim 10, wherein the tabletop is constructed of a plastic material and is formed by blow molding.
- 19. The lightweight folding table of claim 10, wherein the plurality of brackets are secured to the mounting surface independent of mechanical fasteners.
- 20. A lightweight folding table comprising:a tabletop comprising a working surface and a mounting surface disposed opposite the working surface; a plurality of legs independently arranged in supportable relation to the tabletop; a plurality of brackets secured to the mounting surface, each bracket being configured to pivotally attach a leg of the plurality of legs to the tabletop; and wherein the brackets are secured to the mounting surface by an adhesive, the adhesive operating without mechanical fasteners, and wherein the mounting surface further comprises a plurality of fixturing mounts integrally formed with the table top, each fixturing mount comprising a fixturing protrusion configured to restrict lateral motion of one of the plurality of brackets with respect to the table top.
- 21. The lightweight folding table of claim 20, wherein the adhesive is applied between the fixturing protrusion of each fixturing mount and the bracket so as to restrict motion of the bracket in a direction perpendicular to the table top.
- 22. The lightweight folding table of claim 21, wherein the fixturing protrusion of each fixturing mount comprises a plurality of slots configured to receive the adhesive and hold the adhesive against the bracket.
- 23. The lightweight folding table of claim 20, wherein the tabletop is constructed of a plastic material and is formed by blow molding.
- 24. A table comprising:a blow molded tabletop including a working surface and a mounting surface that are generally spaced apart, the blow molded tabletop including a generally hollow interior; a first leg that is capable of moving between a collapsed position and an extended position relative to the tabletop; a second leg that is capable of moving between a collapsed position and an extended position relative to the tabletop; a first mounting bracket attached to the first leg; a second mounting bracket attached to the second leg; a first mounting area integrally formed in the blow molded tabletop as part of a one-piece structure, the first mounting area including one or more protrusions and each protrusion of the one or more protrusions including at least one mounting surface that is sized and configured to help retain the first mounting bracket in a fixed position; and a second mounting area integrally formed in the blow molded tabletop as part of a one-piece structure, the second mounting area including one or more protrusions and each protrusion of the one or more protrusions including at least one mounting surface that is sized and configured to help retain the second mounting bracket in a fixed position.
- 25. The table of claim 24, wherein the first mounting area includes a generally hollow interior that forms a unitary part of the generally hollow interior of the table top, and the second mounting area includes a generally hollow interior that forms a unitary part of the generally hollow interior of the table top.
- 26. The table of claim 24, wherein the first leg is pivotally connected to the first mounting bracket and the second leg is pivotally connected to the second mounting bracket.
- 27. The table of claim 24, further comprising a first channel and a second channel formed in the first mounting area, the first mounting bracket being at least partially disposed within the first channel and the second channel of the first mounting area; and further comprising a first channel and a second channel in the second mounting area, the second mounting bracket being at least partially disposed within the first channel and the second channel of the second mounting area.
- 28. The table of claim 24, further comprising a first abutment surface and a second abutment surface in the first mounting area, the first mounting bracket being sized and configured to engage at least a portion of the first abutment surface and the second abutment surface in the first mounting area; and further comprising a first abutment surface and a second abutment surface in the second mounting area, the second mounting bracket being sized and configured to engage at least a portion of the first abutment surface and the second abutment surface in the second mounting area.
- 29. The table of claim 24, further comprising a first end and a second end of the first mounting bracket, the first end and the second end being sized and configured to assist in connecting the first mounting bracket to the first mounting area; and further comprising a first end and a second end of the second mounting bracket, the first end and the second end being sized and configured to assist in connecting the second mounting bracket to the second mounting area.
- 30. The table of claim 24, further comprising a first tab attached to a first arm of the first mounting bracket and a second tab attached to a second arm of the first mounting bracket, the first tab and second tab of the first mounting bracket being sized and configured to engage one or more surfaces of the first mounting area; and further comprising a first tab attached to a first arm of the second mounting bracket and a second tab attached to a second arm of the second mounting bracket, the first tab and second tab of the second mounting bracket being sized and configured to engage one or more surfaces of the second mounting area.
- 31. The table of claim 24, further comprising a first support strut connecting the first leg to the first mounting bracket and a second support strut connecting the second leg to the second mounting bracket.
- 32. The table of claim 24, further comprising a first slotted member connecting the first leg to the first mounting bracket and a second slotted member connecting the second leg to the second mounting bracket.
- 33. The table of claim 24, further comprising an adhesive that is used to secure the first mounting bracket to the first mounting area and the second mounting bracket to the second mounting area.
- 34. A table comprising:a blow molded tabletop including a working surface and a mounting surface that are generally spaced apart; a mounting assembly integrally formed in the tabletop as part of a one-piece structure, the mounting assembly including one or more outwardly extending protrusions; a mounting bracket attached to the mounting assembly, the mounting bracket including one or more arms that are sized and configured to contact the one or more outwardly extending protrusions; and a table leg attached to the mounting bracket, the leg being capable of moving between a first position in which the leg is generally positioned adjacent to the mounting surface of the table top and a second position in which the leg extends outwardly from the mounting surface of the tabletop.
- 35. The table of claim 34, wherein the blow molded tabletop is substantially hollow.
- 36. The table of claim 34, wherein the mounting bracket is frictionally connected to the mounting assembly in order to secure the leg to the tabletop.
- 37. The table of claim 34, further comprising a plurality of slots in the mounting assembly that are sized and configured to receive the mounting bracket.
- 38. The table of claim 34, further comprising a plurality of channels in the mounting assembly, the mounting bracket being at least partially disposed within the plurality of channels.
- 39. The table of claim 34, further comprising a first tab attached to a first arm of the mounting bracket and a second tab attached to a second arm of the mounting bracket, the first tab and second tab of the mounting bracket being sized and configured to engage one or more engagement surfaces of the mounting assembly.
- 40. The table of claim 34, further comprising a support strut connecting the leg to the mounting bracket.
- 41. The table of claim 34, further comprising a slotted member connecting the leg to the mounting bracket.
- 42. The table of claim 34, further comprising an adhesive that is used to secure the mounting bracket to the mounting assembly.
- 43. The table of claim 34, further comprising a securing member integrally formed in the mounting surface of the tabletop as part of a one-piece structure, the securing member being sized and configured to frictionally engage and retain the leg in the first position.
- 44. A table comprising:a blow molded tabletop including a working surface and a mounting surface that are generally spaced apart; a mounting assembly integrally formed in the tabletop as part of a one-piece structure, the mounting assembly including one or more channels; a mounting bracket attached to the mounting assembly, the mounting bracket including one or more arms that are sized and configured to be inserted into the one or more channels in the mounting assembly; and a table leg attached to the mounting bracket, the leg being capable of moving between a first position in which the leg is generally positioned adjacent to the mounting surface of the table top and a second position in which the leg extends outwardly from the mounting surface of the tabletop.
- 45. The table of claim 44, wherein the blow molded tabletop is substantially hollow.
- 46. The table of claim 44, wherein the mounting bracket is frictionally connected to the mounting assembly in order to secure the leg to the tabletop.
- 47. The table of claim 44, further comprising a plurality of protrusions in the mounting assembly that are sized and configured to retain the mounting bracket in a fixed position.
- 48. The table of claim 44, further comprising a first tab attached to a first arm of the mounting bracket and a second tab attached to a second arm of the mounting bracket, the first tab and second tab of the mounting bracket being sized and configured to engage one or more engagement surfaces of the mounting assembly.
- 49. The table of claim 44, further comprising a support strut connecting the leg to the mounting bracket.
- 50. The table of claim 44, further comprising a slotted member connecting the leg to the mounting bracket.
- 51. The table of claim 44, further comprising an adhesive that is used to secure the mounting bracket to the mounting assembly.
- 52. The table of claim 44, further comprising a securing member integrally formed in the mounting surface of the tabletop as part of a one-piece structure, the securing member being sized and configured to frictionally engage and retain the leg in the first position.
US Referenced Citations (13)