U.S. patent application number 10/846679 was filed with the patent office on 2005-11-17 for retractable table.
Invention is credited to Collins, Thomas, Logan, Stephen.
Application Number | 20050252429 10/846679 |
Document ID | / |
Family ID | 35308198 |
Filed Date | 2005-11-17 |
United States Patent
Application |
20050252429 |
Kind Code |
A1 |
Logan, Stephen ; et
al. |
November 17, 2005 |
Retractable table
Abstract
The retractable table has a single, centrally disposed, vertical
lift column formed of a relatively large number of relatively short
sections. The relatively short sections permit the table to retract
into a relatively shallow receptacle, thus obviating need for a
deep well to house the column when retracted. Column actuation may
be achieved by various principles of operation, including hydraulic
cylinders and helically threaded sections which are rotated to
extend and retract the tabletop. The table has an anti-rotation
feature to prevent rotation of the tabletop relative to the
underlying receptacle in which it stores. The retractable table may
be provided as a "drop-in" installation, with the installer needing
only to cut the required opening in the deck or floor of the
vehicle in which the table is being installed, run appropriate
wiring, and secure the table and its mechanism and receptacle in
place.
Inventors: |
Logan, Stephen; (Easley,
SC) ; Collins, Thomas; (Anderson, SC) |
Correspondence
Address: |
Richard C. Litman
LITMAN LAW OFFICES, LTD.
P.O. Box 15035
Arlington
VA
22215
US
|
Family ID: |
35308198 |
Appl. No.: |
10/846679 |
Filed: |
May 17, 2004 |
Current U.S.
Class: |
108/147 |
Current CPC
Class: |
B60N 3/001 20130101 |
Class at
Publication: |
108/147 |
International
Class: |
A47B 023/00; A47B
037/00; A47B 009/00 |
Claims
We claim:
1. A retractable table, comprising: a floor installation base
having: a peripheral floor attachment flange having at least an
upper surface; a shallow tabletop recess defined within said floor
installation base, and depending below said floor attachment
flange; a lift strut receptacle disposed within said floor
installation base, and depending below the tabletop recess; a
single lift strut having a plurality of concentric, telescoping
lift strut segments retractably extending from said lift strut
receptacle; a power package affixed beneath said floor installation
base, and communicating with said lift strut; and a table top
having at least an upper surface, the table top being disposed atop
said lift strut, the upper surface of the table top being disposed
substantially flush with the upper surface of said floor attachment
flange when said table top is completely retracted.
2. The retractable table according to claim 1, further including:
an outer sleeve concentrically disposed about said lift strut, the
outer sleeve having: a plurality of concentric, telescoping outer
sleeve segments; and means for precluding relative rotation between
each of said outer sleeve segments.
3. The retractable table according to claim 2, wherein said lift
strut and said outer sleeve each comprise: a base segment extending
from said lift strut receptacle; a top segment affixed to said
table top; and a plurality of intermediate segments between the
base and top segments.
4. The retractable table according to claim 2, further including
overextension stop means disposed upon each of the segments of said
lift strut and the segments of said outer sleeve, for precluding
separation of adjacent and mating said segments from one
another.
5. The retractable table according to claim 1, wherein said power
package comprises a hydraulic pump and reservoir driven by an
electric motor.
6. The retractable table according to claim 1, wherein said lift
strut comprises a plurality of concentric, helically threaded,
rotationally extendable and retractable lift strut segments.
7. The retractable table according to claim 6, wherein said power
package comprises an electric motor rotationally driving said lift
strut for the selective extension and retraction thereof.
8. A retractable table, comprising: a floor installation base; a
tabletop; a single lift strut disposed between said floor
installation base and said table top, the lift strut having a
plurality of concentric, telescoping lift strut segments; an outer
sleeve concentrically disposed about said lift strut, the outer
sleeve having: a plurality of concentric, telescoping outer sleeve
segments; and means for precluding relative rotation between each
of said outer sleeve segments.
9. The retractable table according to claim 8, wherein said for
means precluding relative rotation between each of said outer
sleeve segments is selected from the group consisting of mating
keys and channels on adjacent segments and closely fitting,
non-circular segments.
10. The retractable table according to claim 8, further including
overextension stop means disposed upon each of the segments of said
lift strut and the segments of said outer sleeve, for precluding
separation of adjacent and mating said segments from one
another.
11. The retractable table according to claim 8, wherein said floor
installation base further includes: a peripheral floor attachment
flange having at least an upper surface; a shallow tabletop recess
defined within said floor installation base, and depending below
said floor attachment flange; a lift strut receptacle disposed
within said floor installation base, and depending below said table
top recess, said lift strut retractably extending from said lift
strut receptacle of said floor installation base; and a power
package affixed beneath said floor installation base, and
communicating with said lift strut; wherein the table top has at
least an upper surface, the table top being disposed atop said lift
strut, the upper surface of the table top being disposed
substantially flush with the upper surface of said floor attachment
flange when the table top is completely retracted.
12. The retractable table according to claim 11, wherein said lift
strut and said outer sleeve each comprise: a base segment extending
from said lift strut receptacle; a top segment affixed to said
table top; and a plurality of intermediate segments disposed
between the base segment and the top segment.
13. The retractable table according to claim 11, wherein said power
package comprises a hydraulic pump and reservoir driven by an
electric motor.
14. The retractable table according to claim 8, wherein said lift
strut comprises a plurality of concentric, helically threaded,
rotationally extendable and retractable lift strut segments.
15. The retractable table according to claim 14, further including
an electric motor rotationally driving said lift strut for the
selective extension and retraction thereof.
16. A retractable table, comprising: a floor installation base; a
tabletop; a single lift strut disposed between said floor
installation base and said tabletop, the lift strut having: a
plurality of concentric, helically threaded, rotationally
extendable and retractable lift strut segments; a base segment
extending from said floor installation base; a top segment affixed
to said table top; and a plurality of intermediate segments
disposed between the base segment and the top segment.
17. The retractable table according to claim 16, further including
an outer sleeve concentrically disposed about said lift strut, the
outer sleeve having: a plurality of concentric, telescoping outer
sleeve segments; and means for precluding relative rotation between
each of said outer sleeve segments.
18. The retractable table according to claim 17, wherein said means
for precluding relative rotation between each of said outer sleeve
segments is selected from the group consisting of mating keys and
channels on adjacent segments and closely fitting, non-circular
segments.
19. The retractable table according to claim 17, further including
overextension stop means disposed upon each of said segments of
said lift strut and of said outer sleeve, for precluding separation
of adjacent and mating said segments from one another.
20. The retractable table according to claim 16, wherein said floor
installation base further includes: a peripheral floor attachment
flange having at least an upper surface; a shallow tabletop recess
disposed within said floor installation base, and depending below
said floor attachment flange; a lift strut receptacle disposed
within said floor installation base, and depending below said table
top recess, said lift strut retractably extending from said lift
strut receptacle of said floor installation base; an electric motor
rotationally driving said lift strut for the selective extension
and retraction thereof; said table top having at least an upper
surface, said table top being disposed atop said lift strut, the
upper surface of said table top being disposed substantially flush
with the upper surface of said floor attachment flange when said
table top is completely retracted.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates generally to permanently
installed, built-in furnishings having configurations convertible
between a deployed and a stored condition. More particularly, the
present invention relates to a retractable table having a
telescoping central column and cantilevered table platform
extending to all sides therefrom, with the column comprising a
relatively large number of relatively short sections. This enables
the present table and its support column to retract into a
relatively shallow depth, for compact installation and storage.
[0003] 2. Description of the Related Art
[0004] Recreational vehicles, including boats as well as road
vehicles, have become increasingly popular as families with
sufficient time and disposable income indulge their desire to
travel. In the past, most such vehicles were relatively primitively
equipped, often requiring their occupants to cook their meals over
an outdoor campfire and to sleep in sleeping bags. However, there
has been a tendency to provide greater luxury and accommodations in
such boats and road vehicles, including standard beds, kitchenettes
with complete cooking and cleaning facilities, bathroom facilities,
etc.
[0005] Such additional accommodations, of course, require
additional space, and space is already at a premium in most such
vehicles, particularly those of smaller size. As a result, most of
the components which require a relatively large area when deployed
are configured to fold for storage when not in use. In other cases,
components are engineered to provide multiple functions. An example
of such is a dining table and seating arrangement, which can be
folded flat for use as a double bed. In many cases, beds and
seating fold out of the way when not in use.
[0006] Even so, still greater utility and function might be
provided with furnishings which are better engineered for
retraction when not in use. The present invention provides a table
surface which is supported by a single central telescoping column,
with the column comprising a relatively large number of fairly
short sections. This enables the present table to retract into a
recess which requires very little depth, to avoid the need to
penetrate the hull or other structure of the vessel or vehicle for
installation of the present table. The present retractable table is
well suited for installation in a variety of different types of
recreational vehicles, but is particularly well suited for
installation in boats, where its supporting column fixes the table
in place and precludes movement when deployed. Different extension
and retraction mechanisms or principles may be provided for the
operation of the present retractable table.
[0007] A discussion of the related art of which the present
inventors are aware, and its differences and distinctions in
comparison to the present invention, is provided below.
[0008] U.S. Pat. No. 928,726 issued on Jul. 20, 1909 to Guy H.
Witthaus, titled "Disappearing Table," describes a table having
opposed, inwardly folding leg trusses at each end thereof. The leg
trusses fold inwardly, with the table resting level atop the folded
trusses for storage. The leg truss arrangement precludes the
extension of a person's legs beneath the table, when seated at
either end thereof. The extension and retraction of the Witthaus
table is by manual means; no automated or powered extension or
retraction is disclosed.
[0009] U.S. Pat. No. 3,391,960 issued on Jul. 9, 1968 to Robert J.
Megargle et al., titled "Motor Vehicle Interior," describes a
relatively small table secured to an offset, generally vertical
column having limited telescoping capability. The Megargle et al.
table can be pivoted about its column for positioning between the
two front seats of a vehicle, or in front of or between either of
the rear seats. The device cannot retract below a height somewhat
above the seating surface of the front seats, for use as an armrest
between the two front seats. The entire assembly installs atop the
floor of the vehicle, rather than being set into the floor, as in
the present retractable table.
[0010] U.S. Pat. No. 4,019,443 issued on Apr. 26, 1977 to Ferris E.
Jones, titled "Table," describes a non-retracting table in which
the table base extends horizontally to a swivel attachment at the
base of an adjacent seat. The entire table and support may be
swiveled upwardly to place the table against the seat to which it
is attached by the swivel base, for ease in accessing the other
seating. No retraction means is provided.
[0011] U.S. Pat. No. 4,086,859 issued on May 2, 1978 to George V.
Dondero, titled "Boat Table," describes a table having a single
offset support post, allowing the table to be positioned
asymmetrically about the base of the support as desired. The base
of the support post may be removably secured to the underlying
structure by one or more brackets. No retraction means, either
powered or manual, is provided by Dondero for his table.
[0012] U.S. Pat. No. 4,130,070 issued on Dec. 19, 1978 to Cline E.
Herrin, titled "Linearly Translatable Table Top," describes a table
which can translate horizontally atop a fixed base pedestal. No
retraction is provided for the pedestal or tabletop attached
thereto.
[0013] U.S. Pat. No. 4,455,948 issued on Jun. 26, 1984 to Israel
Torres, titled "Automotive Trunk Table," describes a table which
extends from the floor of the trunk of an automobile on a pair of
parallel pantograph arms. The device does not retract into or flush
with the floor structure, and no single telescoping vertical
support column is provided, as such a structure would preclude the
lateral movement of the table to the rear of the vehicle, as
provided by Torres.
[0014] U.S. Pat. No. 4,577,821 issued on Mar. 25, 1986 to Torbjorn
Edmo et al., titled "Lifting Table," describes a table having a
scissor-type support structure, rather than the single, multiple
section telescoping support post of the present table. No
retraction flush with or inset into a floor structure is disclosed
by Edmo et al.
[0015] U.S. Pat. No. 4,620,741 issued on Nov. 4, 1986 to Jacobus N.
Hanemaayer, titled "Combination Table Support And Trunk Access
System For A Recreational Vehicle," describes an essentially fixed
table deployed over a subfloor storage area. The table includes a
primary support leg and a secondary brace which extends over the
storage area. No retraction of the table into the storage area, or
other area, is provided.
[0016] U.S. Pat. No. 5,031,563 issued on Jul. 16, 1991 to Vigbjorn
Matre, titled "System For Utilizing Raisable And Lowerable Berths
In Compartments Having A Limited Space," describes a large number
of embodiments of chair, table, and berth arrangements and
configurations for use in boats, camper vans, truck tractors, and
railroad cars. The table configuration disclosed folds downwardly
onto (but not into) the floor on a pair of fixed length, parallel
legs which pivot from the vertical to the horizontal with the table
remaining secured thereto. No telescoping support column is
provided for the table.
[0017] U.S. Pat. No. 5,069,142 issued on Dec. 3, 1991 to Vigbjorn
Matre, titled "Collapsible Table," describes two different
embodiments of such a table, with one of the table embodiments
being essentially the same as that described immediately above in
the '563 U.S. patent to the same inventor, but disclosed in greater
detail. The other embodiment has support legs forming an X pattern
when deployed, and which fold similarly to a conventional ironing
board or the like. No single telescoping support leg having a
relatively large number of segments is provided by Matre in either
of his two U.S. patents.
[0018] U.S. Pat. No. 5,116,032 issued on May 26, 1992 to Julie
Strachan, titled "Rollingtable With Height Adjustment And Brake
Device," describes an operating table or the like having a
hydraulic system providing limited vertical adjustment. The table
is supported on casters, rather than being permanently installed,
as is the present table. The hydraulic system forces the base
downwardly against the underlying surface to preclude movement of
the table when raised. The device is incapable of folding or
retracting into a floor receptacle.
[0019] U.S. Pat. No. 5,220,698 issued on Jun. 22, 1993 to Keith
Hannant, titled "Patient Support Tables," describes another
operating table using the same principle and system as that of the
Strachan '032 U.S. patent discussed immediately above. It is noted
that the assignee is the same for both the Strachan '032 and
Hannant '698 U.S. patents. The same points of distinction noted in
the discussion of the Strachan '032 U.S. patent are seen to apply
here as well.
[0020] U.S. Pat. No. 5,437,236 issued on Aug. 1, 1995 to Harold R.
Zeiner, titled "Multi-Functional Table With Elevational
Capabilities," describes a table having a pneumatically adjustable
primary support column, with a pair of opposed brace columns. Only
two sections are disclosed for each of the columns, which means
that the table can only be lowered to about half of its fully
extended height. The table cannot be completely lowered in any
event, as a foot pedal is provided at the base of the primary
column, for pumping up the column. Access to this pedal must be
provided beneath the table.
[0021] U.S. Pat. No. 5,503,086 issued on Apr. 2, 1996 to D. Stephen
Hoffmann et al., titled "Table With Movable Top Surface," describes
a coffee table type structure in which the top surface may be
extended on opposed pairs of parallel arms, somewhat like the
tables disclosed in the '563 and '142 U.S. patents to Matre,
discussed further above. The Hoffman tabletop can also rotate about
its attachment to the underlying support structure. Hoffman fails
to provide any means of retracting his table top into a recess in
the underlying floor, however, and does not provide any form of
substantially vertical, telescoping support column.
[0022] U.S. Pat. No. 5,947,416 issued on Sep. 7, 1999 to John R.
Kraft, titled "Floor Rising Cabin Table," describes a pair of
embodiments of a retractable table configured for use in corporate
aircraft, which typically have relatively little interior room. The
primary embodiment utilizes a telescoping tube for support, but the
tube has only two, or at most three, different segments. The result
is a relatively deep installation, with the lower end of the
telescoping tube extending through the pressure vessel or hull of
the aircraft and into the lower wing center section, as shown in
FIG. 12 and described in column 13, lines 29-57.
[0023] Such an installation would be a major effort, as penetration
of the pressurized structure of an aircraft involves major
engineering considerations and work. The cost of the labor in such
an installation would likely be many times the cost of the table
and mechanism itself. Moreover, the lower wing center sections of
such aircraft generally include fuel tanks or baggage storage
areas, and the support column of the Kraft retractable table would
extend into these areas.
[0024] Kraft goes on at the bottom of column 13 to the top of
column 14 to state that a mechanical screw or worm gear support
structure could be configured to fit entirely within the pressure
vessel. However, he does not disclose such a mechanism, and the
only such mechanisms known to the present inventors require
relatively deep receptacles, unless they use a mechanism as
developed by the present inventors and disclosed herein. Moreover,
Kraft fails to provide any means to prevent the rotation of the
table surface about the cylindrical telescoping column, as the
table is raised and lowered. The rectangular configuration of the
folded table of Kraft, must be aligned with its receptacle when
being retracted into the floor. Kraft would require the tabletop to
be rotated by hand for alignment with the floor receptacle.
[0025] The present retractable table avoids these problems by (1)
providing a telescoping column formed of a relatively large number
of relatively short sections, thereby requiring a very shallow
depth when retracted, and (2) including alignment means for all of
the column segments and their supported table top, thereby assuring
that the table top will remain aligned with its receptacle when
retracted. In addition, the drive means for extending and
retracting the table support column is preferably provided with the
remainder of the mechanism for the present invention, as an
integral package. Kraft fails to disclose any specific means for
actuating his table, other than mere mention of a list of known
principles.
[0026] U.S. Patent Application Publication No. 2001/13,307
published on Aug. 16, 2001, titled "Safety Toe-Sensor For Lift
Table," describes a lifting device wherein the lift surface is
raised and supported by a pair of parallel X configuration arms,
similar to the apparatus of the '821 Edmo U.S. patent discussed
further above. The same points raised in the discussion of the Edmo
U.S. patent, i.e. the lack of a central telescoping column and lack
of means for retracting so the table top is flush with the
surrounding floor, are seen to apply here as well.
[0027] British Patent Publication No. 1,559,945 published on Jan.
30, 1980, titled "Operation Table," describes a portable table for
medical use, e.g. X-ray examinations or operations. The table
actually comprises a series of platform sections that may be
angularly adjusted relative to one another, but their height above
the base is essentially fixed atop a fixed pedestal. No vertical
retraction or extension mechanism is disclosed, and the portable
nature of the table does not permit retraction into a floor
receptacle.
[0028] PCT Patent Publication No. WO 87/5272 published on Sep. 11,
1987, titled "Cockpit Table For Boats," describes a table mounted
on a swivel arm. The arm extends horizontally from a bracket, and
rotates about its swivel mounting. The table attaches to the distal
end of the arm, by a swivel mounting. While the table and its
bracket can be removed from a permanent wall mounted anchor, no
retraction means is disclosed.
[0029] PCT Patent Publication No. WO 88/10,081 published on Dec.
29, 1988, titled "Table Having A Table Board The Height Of Which Is
Adjustable," describes an elevated table extending upwardly on a
pedestal from a lower stand. The stand includes a mechanism for
raising the table as desired, and a locking mechanism for fixing
the height of the table as desired. The table may only be lowered
to the top of the stand; the stand rests atop the underlying
surface. No retraction flush with the underlying surface is
possible with the table.
[0030] Japanese Patent Publication No. 64-53,999 published on Mar.
1, 1989, titled "Table Lift," describes (according to the drawings
and English abstract) a scissor type lifting arrangement, with one
of the arms comprising a hydraulic cylinder. The mechanism can lie
relatively flat beneath the table, due to a starting linkage which
initiates the table lift when the system is actuated. This provides
some initial angle for the operation of the hydraulic lift strut to
work. While the assembly can fold to a quite thin and compact
configuration, no vertical telescoping column is provided, nor is
any means of installing the device to lie flush with the floor of a
structure, as provided by the present retractable table.
[0031] Japanese Patent Publication No. 2-175,595 published on Jul.
6, 1990, titled "Lifting Table," describes (according to the
drawings and English abstract) a table and lifting mechanism
recessed into a lower surface or pit. A telescoping hydraulic
cylinder is used to provide the lifting force. However, the
hydraulic mechanism comprises only two segments and cannot be
collapsed to a sufficiently short height as to fit within the
confines to which the present retractable table is directed.
Moreover, no means of preventing relative rotation between the
upper and lower portions of the hydraulic cylinder is apparent in
the '595 Japanese Patent Publication.
[0032] Finally, British Patent Publication No. 2,242,624 published
on Oct. 9, 1991, titled "Operating Table," is based upon the '032
U.S. patent to the same inventor, discussed further above.
Accordingly, the same points raised in the discussion of the '032
U.S. patent are seen to apply here as well.
[0033] None of the above inventions and patents, taken either
singly or in combination, is seen to describe the instant invention
as claimed. Thus a retractable table solving the aforementioned
problems is desired.
SUMMARY OF THE INVENTION
[0034] The present retractable table provides a compactly folding
or retracting article for installation in boats, recreational
vehicles, and cabin-size corporate aircraft, as desired. A key
feature of the present retractable table is its multi-segmented
telescoping support strut. Rather than being formed of two, or
perhaps three, sections, the support strut for the present folding
table is formed of a larger number of shorter sections, enabling
the table to extend to full height above the supporting surface and
still retract compactly in a very shallow receptacle.
[0035] Various means for actuating the present retractable table,
including hydraulic and helically threaded mechanical systems, are
described herein. In both systems, appropriate seals and stop means
are provided in order to preclude overextension of any given pair
of mating segments. Appropriate means for preventing relative
rotation between extension segments is also provided, assuring that
the table remains aligned at all times with the receptacle in which
it retracts.
[0036] The present retractable table is most preferably configured
as a "drop-in" assembly, including a shallow well or receptacle
which may be installed in a cutout in the floor or deck of the
vehicle, boat, or aircraft in which the device is installed. The
installer need only form the required cutout in the surface in
which the present invention is to be installed, run the appropriate
electrical power and control wiring to the installation area,
secure the device within the cutout opening, and connect the
wiring. The hydraulic embodiment of the present retractable table
includes a hydraulic pump and motor power pack as an integral unit
therewith, thus obviating the need for a separate hydraulic system
and plumbing.
[0037] The present retractable table meets the needs of persons
having cabin class boats and aircraft, as well as those with
recreational vehicles, where space is at a premium. The present
table is easily extended by actuation of a switch or the like, to
serve as a table for dining, chart work, games, or other activities
as desired. When the table is no longer needed, it is easily stored
by retracting into its well in the floor.
BRIEF DESCRIPTION OF THE DRAWINGS
[0038] FIG. 1 is a schematic side elevation view in partial section
of a hydraulically operated embodiment of the retractable table
according to the present invention in an extended state, showing
its various features.
[0039] FIG. 2 is a schematic side elevation view in partial section
of the retractable table of FIG. 1 in a retracted state.
[0040] FIG. 3A is a top plan view in section of an embodiment of
the multi-segment hydraulic lifting column of the table of FIGS. 1
and 2, showing the means for preventing relative rotation of the
column segments.
[0041] FIG. 3B is a top plan view of a broken away section of an
alternative embodiment lifting column, showing alternative means
for preventing rotation of the segments relative to one
another.
[0042] FIG. 4 is a schematic side elevation view in partial section
of an embodiment incorporating a number of helically threaded
column segments for raising and lowering the table.
[0043] FIG. 5 is a perspective view in section of the helically
threaded column of FIG. 4, showing the mutually engaging ends of
the segments for preventing overextension of mating segments.
[0044] Similar reference characters denote corresponding features
consistently throughout the attached drawings.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0045] The present invention comprises several embodiments of a
retractable table, suited for permanent (or semi-permanent)
installation in the floor or similar structure of a cabin class
boat, aircraft, or recreational vehicle. The present retractable
table generally includes a base which is installed in a cutout
formed in the vehicle floor, with a single, multiply segmented
telescoping lift strut extending upwardly from the base to support
a table top thereon. The relatively large number of lift strut
segments result in each segment being relatively short, allowing
the lift strut and table to retract flush with the floor without
requiring any substantial depth below the floor for the retracted
lift strut.
[0046] FIG. 1 of the drawings provides a schematic side view in
partial section of a first embodiment of the present retractable
table apparatus in its extended configuration, designated by the
reference numeral 10. The present retractable table assembly 10 is
configured for permanent, or at least semi-permanent, installation
in the deck D or floor of a cabin class boat or yacht, a cabin
class aircraft, or recreational vehicle. A floor installation base
12 includes a peripheral floor attachment flange 14, which secures
atop the deck D or floor using conventional fasteners or other
suitable attachment means. The flange 14 preferably tapers
outwardly to a thin edge, in order to avoid forming a tripping
hazard. The installation base 12 has a shallow tabletop recess 16
located just below the upper surface 18 of the flange 14, for
receiving the table 20 of the present invention when it is
retracted. The tabletop recess 16 is dimensioned to closely fit the
table 20, with the cutout formed in the deck D preferably
dimensioned to fit closely about the exterior of the tabletop
recess 16 in the installation base 12.
[0047] The installation base 12 further includes a lift strut
receptacle 22 in the tabletop recess portion 16 thereof, and
depending below the tabletop recess 16. The lower end of the lift
strut for the tabletop 20 is affixed within this lift strut
receptacle 22. The lift strut 24 is formed of a relatively large
number of relatively short, concentric, telescoping sections or
segments, e.g. a lower or base segment 24a affixed within the lift
strut receptacle 22, a series of five intermediate strut segments
24b through 24f which are extendable from the base segment 24a, and
an uppermost segment 24g to which the table top 20 is affixed. More
or fewer lift strut segments may be provided as desired, depending
upon the height requirement for the extended tabletop 20 and the
depth limitation for the lift strut receptacle 22. However, a
series of seven such lift strut segments 24a through 24g has been
found to provide a suitable compromise in lift height and depth of
the retracted mechanism, without requiring undue complexity.
[0048] Preferably, the lift strut assembly 24 comprises a series of
concentric hydraulic cylinders, with conventional seals disposed
between each segment. A power package comprising a hydraulic pump
26 and fluid reservoir 28 is situated beneath the floor
installation base 12, e.g. secured to the lift strut receptacle 22,
and provides hydraulic fluid under pressure by means of inlet and
outlet lines 30 and 32 between the pump 26 and the base cylinder or
segment 24a. A conventional electric motor and remote switch (not
shown) may be used to actuate the pump 26 as desired to extend or
retract the column 24 and table 20.
[0049] FIG. 2 of the drawings provides an elevation view in partial
section of the retractable table mechanism 10 in its retracted
state. In FIG. 2, the central lift strut 24 has been collapsed or
retracted, with the smaller diameter segments nesting within the
larger diameter segments. The segments forming the outer sleeve
assembly 34 are nested in the same manner. The large number of
relatively short segments forming the lift strut 24 and outer
sleeve assembly 34, allow the table top 20 to be retracted so that
its upper surface 36 is flush or essentially coplanar with the
upper surface 18 of the peripheral mounting flange 14 of the floor
installation base 12, while still providing a relatively shallow
depth for the lift strut receptacle 22 and its removable access
cover 38.
[0050] As the hydraulic cylinder segments 24a through 24g are
circular in cross section, there is nothing per se to preclude
relative rotation of any of the cylinder segments relative to one
another. This may not be critical in the case of a round table 20
and correspondingly shaped circular table receptacle 16 in the
installation base 12, but it is important where a non-circular
tabletop 20 and correspondingly shaped recess 16 are provided.
Accordingly, the present retractable table mechanism 10 includes an
outer sleeve assembly 34, as noted above, which serves to maintain
the alignment of the tabletop 20 with its underlying recess 16. The
outer sleeve assembly 34 comprises a base sleeve 34a (which may be
the same as the lift strut receptacle 22), a series of concentric,
telescoping intermediate sleeves, e.g. sleeve segments 34b through
34f, and an uppermost sleeve segment 34g. Preferably, the number of
outer sleeve segments 34a through 34g is the same as the number of
hydraulic cylinder segments 24a through 24g, although the limiting
factor for the extension and retraction height of the assembly 10
is the length of the longest cylinder or sleeve segment, if they
are not of equal length.
[0051] The series of outer sleeve segments 34a through 34g each
include some form of cooperating linear engagement means to
preclude relative rotation between each of the immediately adjacent
segments, and thus between the lift strut receptacle 22 comprising
the lowermost outer sleeve segment 34a and the uppermost outer
sleeve segment 34g with its attached table top 20. FIGS. 3A and 3B
illustrate examples of such anti-rotation means. In FIG. 3A, a
series of outer sleeve segments 34a through 34g concentrically
surround the inner lift strut segments 24a through 24g. The outer
sleeve segments 34b through 34g all include at least one (and
preferably two or three) linear channel(s) 40 formed in their outer
walls, with the segments 34a through 34f all having corresponding
linear ribs 42 formed along their inner walls and engaging the
corresponding channels 40 of the inwardly adjacent segments. The
engagement of the channels 40 and ribs 42 prevent relative rotation
between adjacent segments, thus preventing rotation of the
innermost segment 34g, and its attached table top 20 (shown in
FIGS. 1 and 2) relative to the outermost base segment 34a. It will
be seen that the orientation of the channels and ribs may be
reversed if so desired, with the ribs extending outwardly and
channels extending inwardly, or other engagement means may be used
as desired.
[0052] FIG. 3B provides a broken away plan view in section of an
alternative outer sleeve assembly of non-circular cross section,
designated as sleeve assembly 35. The inner hydraulic cylinder
assembly 24, comprising segments 24a through 24g, is essentially
identical to the assembly 24 shown in FIGS. 1 and 2. However, the
outer sleeve assembly 35 is formed of a series of non-circular
segments 35a through 35g, with each of the segments having the same
non-circular shape and being progressively smaller to fit closely
within one another. (It should be noted that clearances between
segments 24a through 24g and 35a through 35g in FIG. 3B, and
clearances between segments 24a through 24g and 34a through 34g in
FIG. 3A, are exaggerated for clarity in the drawing Figs.) The
non-circular configuration of the outer sleeve segments may be
square, as shown, or may alternatively be of any regular or
irregular shape as desired, so long as they share the same shape
but vary progressively in size from the largest to the smallest
segment, in order to fit closely with one another and preclude
relative rotation of any of the segments.
[0053] To this point, a hydraulic operating system has been
described for extending and retracting the table top of the present
invention. However, it will be seen that other actuating mechanisms
may be provided, as desired. One such mechanism may comprise a
series of concentric, helically threaded segments 124a through 124g
forming a threaded lift strut 124, as illustrated in FIG. 4 of the
drawings. An outer sleeve assembly, e.g. sleeve assembly 34
comprising segments 34a through 34g, is provided to prevent
rotation of the table top 20 relative to the base 12 and its table
top recess 16. The helically threaded lift strut assembly 124
operates by means of an electric (or alternatively, hydraulic)
motor 44, which communicates with a drive wheel 46 extending from
the lower end of the first helical segment 124a. Conventional belt
or chain drive, gearing, etc. (not shown) may be used to connect
the rotation of the motor 44 to the lift strut drive wheel 46.
(Such an electric motor 44 may also be used to drive the hydraulic
pump 26 of the hydraulically actuated embodiment of FIGS. 1 and
2.)
[0054] The helically threaded lift strut embodiment of the present
retractable table is illustrated in its extended or deployed
position in FIG. 4. From an initial stored or retracted
configuration, rotation of the drive wheel 46 also rotates the
first helically threaded segment 124a, which causes the second
segment 124b to unthread from its stored position within the first
segment 124a. When the second segment 124b has reached the end of
its threaded extension from the base segment 124a, it will also be
forced to rotate, thereby causing the third segment 124c to
unthread from the second segment 124b. This sequential unthreading
operation will continue until all of the lift strut segments 124a
through 124g have unthreaded themselves from one another to their
limits, thus causing the table top 20 to rise to its fully deployed
position as shown in FIG. 4. While the unthreading of the segments
124a through 124g has been described as a sequential operation, it
should be noted that the order of relative rotation may vary
depending upon friction between segments, and is not critical.
[0055] It will be understood that some means is required for
preventing the overextension of the various segments, in order to
prevent segments from disassembling from one another as they
extend. FIG. 5 provides a detailed perspective view in section of
the outer sleeve assembly 34 and its segments 34a through 34g, as
well as the helically threaded lift strut 124 and its segments 124a
through 124g, showing the overextension stop means provided. Each
of the outer sleeve segments 34a through 34f includes an upper,
inwardly extending flange 48, with each of the segments 34b through
34g having a lower, outwardly extending flange 50 of smaller inner
diameter than the outer diameter of the corresponding opposite
flange 48. Thus, when the outer sleeve 34 extends to its maximum
height, each of the outer flanges 48 is prevented from
overextension by its contact with the overlying inner flange of the
next sleeve unit or segment. This same principle may be used to
limit the extension of the hydraulic strut assembly 24 shown in
FIGS. 1 and 2, as well, or other overextension stop means (e.g.,
conventional grooves with internal and/or external snap rings,
etc.) may be used.
[0056] Overextension of the helically threaded lift strut segments
124a through 124g is prevented in much the same manner, with each
of the segments 124a through 124f having an upper, inwardly
extending flange 52 and each of the segments 124b through 124g
having a lower, outwardly extending flange 54. Alternative
overextension prevention means may be used, as noted above in the
description of such means for the lift strut 124. However, each of
the inwardly extending flanges 52 of the helically threaded lift
strut segments 124a through 124f includes internal threads 56,
which engage the external threads of the adjacent inner lift strut
segment. In this manner, rotation of any lift strut segment
relative to its immediately adjacent lift strut segment results in
the extension or retraction of the two segments relative to one
another, depending upon the relative direction of rotation.
[0057] As noted further above, the rotational extension or
retraction of the helically threaded segments 124a through 124g may
be sequential, or in some other order, depending upon relative
friction between adjacent segments. However, the order of extension
or retraction is not critical, as when any two segments have
reached their fully extended state, the abutting outward and inward
flanges 52 and 54 of any two mating segments prevent further
extension and cause the two segments to rotate together as one
unit, thereby transferring relative rotation to other segments of
the assembly until extension is complete.
[0058] While not shown in the drawings, additional lower, inwardly
extending flanges or upper, outwardly extending flanges may be
provided opposite their counterparts 48, 52 and 50, 54 on the outer
sleeve segments 34a through 34g and the lift strut segments 124a
through 124g (or the hydraulic lift strut segments 24a through 24g
of FIGS. 1 and 2). This serves to prevent the higher segments from
dropping through the lower and larger diameter segments, when the
assemblies are retracted. Again, other means may be used, e.g.
circumferential grooves and snap rings, etc.
[0059] In conclusion, the present retractable table in its various
embodiments provides a much needed means of creating a table for
dining, chart work, games, or any other suitable purpose, which may
be retracted into the floor for unobtrusive storage when not
needed. A simple throw rug or the like may be spread over the
retracted table surface when floor space is needed, in order to
protect the table surface when retracted. Alternatively, folding
extension leaves may be provided from the edges of the table to
expand the surface area of the table when in use, with the leaves
folding over the top of the table to protect the table surface when
retracted into the floor. The present retractable table assembly is
easily installed, as it is provided in an installation base which
is easily secured within the floor, once the appropriate cutout has
been formed in the floor. Accordingly, the present retractable
table will be favorably received by owners of cabin class boats and
aircraft, recreational vehicles, and others who have need for a
retractable table surface within a confined area.
[0060] It is to be understood that the present invention is not
limited to the embodiments described above, but encompasses any and
all embodiments within the scope of the following claims.
* * * * *