Patent Application
20090205541
The present invention relates generally to a mechanism for adjusting the tilt of a top surface, and more particularly to a mechanism for a flip-top table having improved stability, robustness, ease of use, and ease of manufacture.
Tables with titling tops are well known in the art. Designers of flip-top tables, however, have faced many challenges in designing the mechanism that allows the top to tilt and preferably lock in place. First, the rigidity of a flip-top table must be comparable to conventional non-flip tables. Second, the mechanism must be simple to manufacture and preferably accommodate a variety of leg and table top sizes so that a single style of mechanism may be manufactured for multiple table designs.
Third, the mechanism must allow the table to fold in a manner so that the table may pass through a standard doorway. Fourth, the mechanism must be able to satisfy government regulations, such as those set by OSHA, and non-governmental organization's standards, such as the Business and Institutional Furniture Manufacturer's Association.
Fifth, pinch points at the location of mechanism activation must be minimized to reduce the risk of injury to the table operator. Sixth, the operation of the mechanism should be intuitive and a single or dual operation should be used for releasing the table top from multiple positions.
Seventh, the mechanism must latch when the table is in a “use” position and the mechanism must latch or clip when the table is in a “folded” position. Eighth, the mechanism must provide a signal to the operator that the mechanism has locked. A preferable signal to the operator is an audible sound.
Ninth, the mechanism must be difficult to accidentally activate when it is bumped or kicked by a person using the table. Tenth, the design of the mechanism must work with a free-swinging modesty panel.
Eleventh, the mechanism should inhibit bidirectional rotation about a rotation axis when the table is in the “use” and “folded” positions. Twelfth, the mechanism may be used to limit the speed of rotation of the table top when the table is transitioning between positions.
Finally, the mechanism should be constructed from lightweight yet robust materials. The mechanism should utilize unique latching features for each unique configuration because utilizing different portions of the mechanism helps to evenly spread the wear on the mechanism. Utilizing separate features for each latching position also allows the mechanical tolerances of the design and table wobble to be reduced. Additionally, separate features may be individually customized (strengthened, etc.) based
There have been many attempts to address these challenges faced by designers of flip-top table mechanisms. For example, U.S. Pat. No. 1,203,783 issued to Reischmann and U.S. Pat. No. 3,641,946 issued to Charnay disclose lockable mechanisms for pivoting tables. The mechanisms have springs that are securable to a plurality of rods or holes, with each rod or hole corresponding to a unique table position. The '783 and '946 patents, however, do not provide unique spatially separated latching features since one spring interacts with all the rods or holes. Additionally, the latching mechanisms of the '738 and '946 patents are only functional with one type of table leg because the legs are integrated into the mechanisms, thus the need remains for an improved flip-top table mechanism.
U.S. Pat. No. 4,986,195 issued to Diffrient discloses a “tilting table top mechanism . . . [with] a chassis member which is secured to the underside of a table top and a base plate which is secured to the top of a table leg. A dual locking mechanism maintains the table top in its normal ‘use’ position but is manually disengaged with ease.” The mechanism of the '195 patent does not bi-directionally lock the rotation of the table in a folded configuration, thus the need remains for an improved flip-top table mechanism.
U.S. Pat. No. 3,796,169 issued to Bales and Estes discloses a flip-top table mechanism that utilizes unique portions of the latch for each configuration of the table. However, the mechanism of the '169 patent has several pinch points near the activation point of the mechanism.
Accordingly, an object of the present invention is to provide an easily manufacturable mechanism for a flip-top table with rigidity comparable to a non flip-top table.
Another object of the present invention is to provide an intuitively operable mechanism that meets government and industry standards.
Yet another object of the present invention is to provide a flip-top table mechanism that is capable of locking a table in both a use and folded position.
Still another object of the present invention is to provide a mechanism that gives an audible signal when locking.
A still further object of the present invention is to provide a single release mechanism capable of releasing the table top from both a folded and a use position while being difficult to accidentally engage.
The present invention provides an improved mechanism for operating a flip-top table. While maintaining the benefits of standard mechanisms, the mechanism of the present invention also achieves many benefits including improved table rigidity, an intuitively operable release mechanism, a single release action for both the “use” and “folded” positions, and spatially separated latches for the “use” and “folded” positions. Additionally the present invention provides a mechanism that meets or exceeds government and industry standards and has a refined appearance.
The present invention may be used with any type of flip-top structure and is particularly suited for applications requiring a lightweight, rigid, and robust mechanism with a intuitively operated release action. The improved flip-top table mechanism of the present invention may be used with flip-top objects such as chairs, tables, stadium seating or benches. However, for descriptive purposes, the present invention will be described in use with a flip-top table.
The storage latch and the use latch may be significantly different in shape or size depending on the forces expected to act upon the mechanism when the table is in the various configurations. For example, the storage latch may be reinforced if it is expected that the table top will be bumped while in the folded configuration. Conversely, the storage latch may be significantly thinner than the use latch if the mechanism is designed for a table that is only briefly put into the folded position on rare occasions.
A spring is shown pulling on the latching piece, however a variety of pulling means such as magnets, belts, ropes connected to weights, and rubber bands may be used to pull upon the latching piece.
Although the cable assembly connects to a groove in
The base piece is preferably constructed as a unitary piece from an extrusion process or other mass manufacture process. The base piece may be constructed having a mirror plane 127 to reduce design and manufacture costs for the base piece. The mirror plane also serves to provide a base piece of refined appearance.
The spatial separation of the hinge area and the latch area on the base piece serves to increase the structural rigidity of the table by minimizing the effects of any movement or gaps between the use latch and the latching edge. Assuming the latching mechanism is positioned at the center of a table, the total wobble at the end edge of the table is approximately:
Where Table Wobble is the vertical wobble at the edge of the table due to the latching mechanism, Table Width is the width of the table, Ledge Wobble is the difference between the minimum and maximum vertical distance between the latching edge and the use latch, and Distance is the separation between the hinge area and the latch area. As clearly shown, increasing the separation between the hinge area and the latching area has a significant impact on the stability of a flip-top table.
The components of the mechanism may be constructed from a wide variety of materials such as plastics, metals, natural materials, and composite materials. Materials contemplated by the inventor include molded glass, fiberglass, nylon, glass material, stamped steel, stamped aluminum, carbon/nylon reinforced textile sheets, amarid, polyester, and carbon fiber. For components created by an extrusion process, the resins contemplated by the inventor include epoxy, unsaturated polyester, urethane acrylate, vinyl ester, phenol, polyurethane, a thermoplastic resin, nylon 6, nylon 66, nylon 12, PBT, PET, polycarbonate, polyacetal, polyphenylene sulfide, polyether ether ketone, polyether sulfide, polyphenylene oxide, modified polyphenylene oxide, polypropylene, and polyvinyl chloride, ethylene-vinyl acetate copolymer, polystyrene, acrylonitrile-butadiene-styrene copolymers (ABS), 6, 11, 12, 6-6 and 6-10 polyamides, poly(ether amide) sequenced copolymer, fluorinated polymers, polysulfone, polyethersulfone, polycarbonate, polyetheretherketone, polyphenylene sulfur, polyetherimide, and polyphenylene ether.
As shown in
The inventor contemplates several alterations and improvements to the disclosed invention. The latching and release mechanisms may further include protective and/or decorative coatings such as paint. Other alterations, variations, and combinations are possible that fall within the scope of the present invention. For example a spring may be added between the base piece and the top plate so that the mechanism will automatically transition from a “use” position to a “folded” position when the latching piece is released from the ledge. Although various embodiments of the present invention have been described, those skilled in the art will recognize more modifications that may be made that would nonetheless fall within the scope of the present invention. Therefore, the present invention should not be limited to the apparatus described. Instead, the scope of the present invention should be consistent with the invention claimed below.
