U.S. patent number 3,695,693 [Application Number 05/061,707] was granted by the patent office on 1972-10-03 for seat construction.
This patent grant is currently assigned to Tartan Corporation. Invention is credited to Hugh C. Acton, Roy W. Fink.
United States Patent |
3,695,693 |
Acton , et al. |
October 3, 1972 |
SEAT CONSTRUCTION
Abstract
Base structure for seat means including a U-shaped support
member having four upright legs defining two substantially parallel
planes, said member being secured by connection means to a rigid,
substantially horizontal frame member of the seat means. Said base
structure and seat means may be arranged to permit stacking. A pair
of runners are attached near the central portions thereof to the
lower ends of the legs in parallel relationship to each other and
transversely of said planes for engagement with a supporting
surface.
Inventors: |
Acton; Hugh C. (Ross Township,
Kalamazoo County, MI), Fink; Roy W. (Portage, MI) |
Assignee: |
Tartan Corporation (Kalamazoo,
MI)
|
Family
ID: |
22037576 |
Appl.
No.: |
05/061,707 |
Filed: |
August 6, 1970 |
Current U.S.
Class: |
297/239; D6/371;
297/445.1 |
Current CPC
Class: |
A47C
3/04 (20130101); A47C 7/002 (20130101) |
Current International
Class: |
A47C
3/04 (20060101); A47C 7/00 (20060101); A47C
3/00 (20060101); A47c 003/04 () |
Field of
Search: |
;297/239,248,445,457
;248/188,188.8 ;108/91 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
478,756 |
|
Jan 1938 |
|
GB |
|
1,150,233 |
|
Aug 1957 |
|
FR |
|
585,512 |
|
Feb 1947 |
|
GB |
|
575,965 |
|
Mar 1946 |
|
GB |
|
Primary Examiner: Zugel; Francis K.
Claims
The embodiment of the invention in which an exclusive property or
privilege is claimed are defined as follows:
1. Base structure for seat means having a rigid, substantially
horizontal frame member comprising:
elongated, rigid, downwardly opening, channel-shaped bridge means
having substantially flat plate means with first and second,
integral and spaced projection means extending downwardly from said
plate means; connection means adapted to rigidly secure said bridge
means to said frame member; a pair of similar, rigid, spaced,
parallel and U-shaped elements, each element having a crossrod and
legs extending perpendicularly and in substantially the same
direction from said cross-rod, said U-shaped elements defining
spaced and substantially parallel planes, said crossrods being
disposed between said projection means and extending in the
elongated direction of said bridge means, said cross-rods being
rigidly connected to said bridge means by being located at and
fixedly secured in the respective corners defined by the junctures
of said first and second projection means with said plate means;
and a pair of elongated, substantially straight runner means, each
of said runner means being rigidly secured near the center thereof
to the free end of one leg of each U-shaped element, said runner
means being substantially parallel with each other and transverse
of said planes.
2. A base structure according to claim 1,
wherein said projection means extend in the longitudinal direction
of the bridge means and comprise parallel, integral flanges
extending in the same direction from and substantially
perpendicularly to said plate means; and
wherein said crossrods are secured by welds to said flanges and
said plate means at intervals lengthwise thereof, said welds being
spaced from the lengthwise ends of said bridge means.
3. A base structure according to claim 1 wherein said bridge means
is substantially channel-shaped and said projection means are
flanges, said crossrods being rigidly secured to said flanges and
said plate means;
wherein said runner means are located on the outside of said legs;
and
wherein the free ends of said legs are flattened and offset so that
the inner surface of each runner means is substantially located
outside of a plane defined by the outside surfaces of the two legs
secured to such runner means.
4. A base structure according to claim 1 wherein said crossrods are
welded to said bridge means and the welds are spaced substantially
from the points on said crossrods of maximum deflection and stress;
and
wherein said connection means includes a rigid mounting plate
secured to said frame member and said bridge means.
5. A base support structure according to claim 1 wherein the
adjacent legs of said U-shaped elements are substantially parallel
and are laterally spaced from each other by a distance slightly
greater than twice the thickness of each leg; wherein said
crossrods extend beyond opposite edges of the seat means by a
distance slightly greater than the thickness of said legs; and
wherein said runner means are disposed on the outer sides of said
legs outwardly of a plane defined by the outer surfaces of said
legs whereby one said seat means having a said base structure can
be stacked upon another of said seat means attached to a said base
structure with the legs of one U-shaped element of said one base
structure being nested within the legs of said other base
structure.
6. A base structure according to claim 1 wherein said runner means
have substantially flat lower surfaces adapted to engage a
substantially flat supporting surface, the combined area of said
lower surfaces being in the range of between 10 and 20 square
inches.
7. In a seat structure having seat means provided with a rigid and
substantially horizontal frame member on the underside thereof and
a vertically extending base structure fixedly secured to the frame
member, said base structure being adapted to be supported on a
substantially horizontal support surface for maintaining said seat
means elevated above said surface, the improvement wherein said
base structure comprises:
elongated, rigid, downwardly opening, channel-shaped bridge means
fixedly secured to said horizontal frame member, said bridge means
having a substantially flat plate means and first and second spaced
projection means fixedly connected to said flat plate means
adjacent the opposite longitudinal edges thereof, said projections
extending downwardly from said flat plate means and being spaced
substantially inwardly from the outer edges of said seat means
which extend in generally the same direction as the longitudinal
edges of said flat plate means;
a first pair of substantially parallel leg members fixedly
interconnected to said bridge means adjacent one longitudinal end
thereof, said leg members being positioned closely adjacent but
laterally spaced from one another and each including a
substantially horizontal portion fixedly connected to said bridge
means and extending outwardly to a point disposed adjacent an edge
of said seat means, the horizontal portions of said first pair of
leg members being disposed between said projection means and being
located at and fixedly secured in the respective corners defined by
the junctures of said first and second projection means with said
plate means, each of said leg members also including a
substantially vertical portion integrally connected to the outer
end of said horizontal portion and extending vertically downwardly,
whereby the vertical portions of said leg members are substantially
perpendicular to their respective horizontal portions;
a first elongated and substantially straight runner member fixedly
and rigidly secured to the lower end of the vertical portions of
said first pair of leg members, the lower ends of said vertical
portions being fixedly secured to said runner substantially near
the center thereof, said runner extending substantially
horizontally in a direction substantially perpendicular to the
longitudinal direction of said bridge means;
a second pair of substantially parallel leg members fixedly secured
to said bridge means adjacent the opposite end thereof, said second
pair of leg members also being closely adjacent but laterally
spaced from one another and each including a substantially
horizontal portion fixedly secured to said bridge member and
extending outwardly to a point adjacent an edge of said seat means,
the horizontal portions of said second pair of leg members being
disposed between said projection means and being located at and
fixedly secured in the respective corners defined by the junctures
of said first and second projection means with said plate means,
each of said leg members also including a substantially vertical
portion having the upper end thereof rigidly connected to the outer
end of said horizontal portion, said vertical portions being
substantially perpendicular to their respective horizontal
portions; and
a second elongated and substantially straight runner member rigidly
secured to the lower ends of the vertical portions of said second
pair of leg members, said lower ends of said vertical portion being
secured to said second runner member substantially near the center
thereof, and said second runner member also extending substantially
horizontally in a direction substantially perpendicular to the
longitudinal direction of said bridge means, whereby said first and
second runner members are substantially parallel to one
another.
8. A seat structure according to claim 9,
wherein one of the legs of said first pair and one of the legs of
said second pair are integrally connected to form a first
substantially U-shaped member; and
wherein the other leg of said first pair and the other leg of said
second pair are also integrally connected to form a second
substantially U-shaped member disposed closely adjacent but
laterally spaced from said first U-shaped member in parallel
relationship therewith.
9. Base structure for seat means having a rigid substantially
horizontal frame member comprising:
elongated, rigid bridge means having substantially flat plate means
with first and second, integral and spaced projection means
extending downwardly from said plate means;
connection means adapted to rigidly secure said bridge means to
said frame member;
a pair of similar, rigid, spaced and U-shaped elements, each
element having a crossrod and legs extending perpendicularly and in
substantially the same direction from said crossrod, said U-shaped
elements defining spaced and substantially parallel planes, each
crossrod extending in the elongated direction of and being rigidly
connected to said bridge means and located adjacent one of said
projection means;
said bridge means comprising a pair of channel members disposed on
opposite sides of said crossrods and opening toward each other,
said channel members having flanges welded to each other and to
said crossrods; and
a pair of elongated, substantially straight runner means, each of
said runner means being rigidly secured near the center thereof to
the free end of one leg of each U-shaped element, said runner means
being substantially parallel with each other and transverse of said
planes.
Description
BACKGROUND OF THE INVENTION
This invention relates in general to a seat construction and, more
particularly, to a base or support structure for seat means, which
base structure is capable of stacking, capable of use with a
variety of seat means, resistant to tipping, sufficiently
resiliently flexible to give greater comfort to the occupant of the
seat means, and designed to minimize wear on or damage to the
supporting surface.
Persons acquainted with the manufacture and use of chairs, seats
and similar devices for supporting human beings will immediately
recognize that the hereinafter described invention provides a
completely new departure in seat base constructions. In particular,
the base structure for the seat overcomes or avoids a number of
problems which have been virtually inherent in chairs since they
were first built. Specifically, many conventional, four-legged
chairs are easy to tip, particularly in a backwards direction where
the occupant is almost helpless to prevent his own injury which is
often serious.
The conventional chair is virtually inflexible. That is, the base
structure is such that it well not flex when it is occupied. Thus,
any change in the position of the occupant necessitates an
adjustment of the occupant to the chair, because the chair, or seat
thereof, will not adjust with the occupant.
It is difficult to clean the floor around a conventional chair and,
as a rule, the chair must be moved. The upright legs of the
conventional chair are constantly in the way and in a short period
of time clearly confirm this fact by the nicks and mars thereon. In
spite of efforts to the contrary by manufacturers, the legs of the
conventional chair make virtually pinpoint contact with their
supporting surface. Accordingly, carpeting, tile, wood or any other
known conventional supporting surface in homes, schools, offices
and the like soon become torn, worn, gouged, dimpled or scratched
by chair legs.
It is well known that chairs used in schools, institutions and the
like are advantageously capable of stacking when not in use in
order to minimize storage space. Many types of stackable chairs
have been developed, but the commercially acceptable types are
designed with individual legs for pinpoint contact with the floor
or other supporting surface.
Chairs of the type used in residences or offices must be readily
capable of variations in color and style to accommodate demands of
decor. Usually, this is accomplished by modifying the seat and back
structures. Thus, there has been a real need for an attractive,
sturdy base or support structure which can be quickly and easily
attached to a wide variety of seat and back arrangements in order
to satisfy individual needs and tastes.
Accordingly, a primary object of this invention is the provision of
a seat construction having base structure rigidly secured to the
seat means but capable of flexing in order to permit some movement
of the seat means relative to the supporting surface when said seat
means is occupied, and wherein the base structure includes
elongated runners which engage the supporting surface along an
extensive area so that wear on or damage to the supporting surface
by the base structure is at least reduced if not eliminated.
A further object of the invention is the provision of a base
structure for a seat construction which has greater than average
resistance to tipping backwards and which minimizes lateral tipping
by virtue of the location and extent of said runners, said base
structure being capable of use with and adaptation to a wide
variety of seat means to provide chairs, benches, couches and the
like.
A further object of this invention is the provision of a seat
construction, as aforesaid, which creates a minimum of interference
for cleaning operations around the seat construction, which is
capable of stacking, which avoids structural failures by avoiding
conventional stress points and which minimizes obstruction to
movement of the occupant of the seat means around the seat
means.
Other objects and purposes of this invention will be apparent to
persons familiar with this type of equipment upon reading the
following descriptive material and examining the accompanying
drawings, in which:
FIG. 1 is a perspective view of a seat construction having a base
structure embodying the invention;
FIG. 2 is a fragmentary front elevational view of said seat
construction;
FIG. 3 is a sectional view substantially as taken along the line
III--III in FIG. 2;
FIG. 4 is a broken sectional view taken along the line IV--IV in
FIG. 2;
FIG. 5 is a broken fragment of FIG. 2 as viewed from the cutting
line V--V;
FIG. 6 is a fragment of FIG. 4 illustrating a modified
structure;
FIG. 7 is a side elevational view of a plurality of said seat
constructions arranged in stacked positions;
FIG. 8 is a sectional view taken along the line VIII--VIII in FIG.
7; and
FIG. 9 is a front elevational view of a modified seat construction
embodying the invention.
For convenience in description, the terms "upper," "lower,"
"front," "rear" and words of similar import will have reference to
the seat construction as appearing in FIG. 2, for example, wherein
the front side of the seat construction is shown. The terms
"inner," "outer" and derivatives thereof will have reference to the
geometric center of said seat construction and parts thereof.
SUMMARY OF THE INVENTION
The objects and purposes of the invention, including those set
forth above, are met by providing a base structure having a
U-shaped support member including crossbar means and a pair of
substantially parallel legs extending downwardly from the opposite
ends of said crossbar means. The crossbar means of the support
member is attached to a rigid frame member that is part of a seat
means. A pair of parallel, substantially coextensive runners are
connected to the lower extremities of the legs, one runner being on
each side of the chair.
DETAILED DESCRIPTION
The seat construction, here a chair 10 which is illustrated in
FIGS. 1 and 2, comprises an occupant engaging portion having a seat
11 and back 12 which, in this particular embodiment, are formed in
a molding operation as integral members made from plastic
impregnated with fiberglass. However, other materials may be used.
A seat cushion 13 may be supported upon the seat 11, and
upholstering may be used as desired. The seat, back and cushion of
said chair 10 may be, and preferably are, substantially
conventional in structure, provided that said seat 11 has a
relatively rigid part engageable from below it.
The chair 10 (FIG. 1) has a base structure 15 which, in combination
with the seat 11, comprises the novel improvement in said seat
construction. Specifically, the base structure 15 comprises a pair
of elongated support elements 16 and 17 which are U-shaped and
fabricated from steel rod in this particular embodiment. However,
other metals or plastics might be used, and the elements 16 and 17
can be tubular, either round or rectangular in cross section.
Support element 16 has a crossrod 18 and a pair of parallel legs 19
and 20 which extend substantially perpendicularly from the crossrod
18, except for a slight radius at their connections with the
crossrod 18. The support element 17 has a crossrod 23 and a pair of
legs 24 and 25 which are arranged so that they are preferably
identical with the arrangement of legs and crossrod in the element
16. While the legs 19,20 and 24,25 are illustrated as being
parallel, their may be circumstances where it is desirable to have
legs 19 and 24 diverge slightly downwardly with respect to the legs
20 and 25, respectively, to facilitate stacking operations
discussed hereinafter.
The lower ends of the legs 19 and 24 (FIGS. 4 and 5) are flattened
at 27 and 28, respectively, in order to facilitate their
connection, as by brazing or welding, for example, to the runner
29. It will be observed in FIG. 8 that the flattening is
accomplished so that the sides thereof engaged with the runner are
slightly beyond the plane defined by the corresponding outer edges
of the legs above the flat portions. This arrangement accomplishes
two purposes, namely, it permits stacking and it moves the point of
maximum deflection and stress upwardly away from the runner which
at least reduces the chances of breaking the connection between the
legs and the runner. In this embodiment, the distance between the
legs 19 and 24 or the legs 20 and 25 is preferably approximately
twice the thickness of any one of said legs. This arrangement
permits the stacking disclosed in FIG. 7.
The lower ends of the legs 20 and 25 also have flat portions, as
shown at 32 in FIG. 2 with respect to the leg 20, which flat
portions are secured by welding or brazing to the central portion
of a runner 33. The runners 29 and 33 are preferably parallel for
normal use and preferably perpendicular to the legs 19,24 and
20,25. However, under some circumstances, it may be desirable to
cant or slope the legs forwardly or rearwardly relative to the
runners 29 and 33 and this application contemplates such
possibility. Although the runners 29 and 33 are shown herein as
rectangular in cross section, other cross-sectional shapes may be
employed.
In this particular embodiment, each of the runners 29 and 33 has a
substantially flat and downwardly facing surface of approximately
13 square inches. The front and rear ends of each runner are curved
so that they cannot catch the pile of carpeting or the raised edges
of tiles as said chair is moved across the floor. The total floor
engaging surface of the legs on an average four-legged chair does
not exceed four square inches.
In one embodiment of the invention, the crossrods 18 and 23 (FIG.
3) are engaged by a channel-shaped, steel bridge member 34 having a
web 36 and a pair of flanges 37 and 38 which are parallel with each
other and perpendicular to the web 36. The crossrod 18 is
preferably welded at zones 39 to the flange 37 and at zones 40 to
the web 36. The cross-rod 23 is welded to the flange 38 at zones 42
and to the web 36 at zones 41. The outermost ones of the weld zones
39 and 42 are spaced inwardly from the end of the bridge member 34,
thereby spacing such outermost welds from the points of maximum
deflection of, and stress upon, the crossrods 18 and 23, which
points are located at the lengthwise edges of said bridge member.
Thus, the chance of breaking the outermost welds due to stress upon
and deflection of the crossrods is at least reduced.
A mounting plate 43, (FIGS. 3 and 4), preferably fabricated from
rigid steel plate, is rigidly secured to the seat portion 11 of the
chair 10 by means of screws 44 which are slidably received through
openings 46 in the plate 43 and threadedly received into openings
47 in the seat portion 11. The web 36 of the bridge member 34 is
rigidly secured to the mounting plate 43 by means of the nuts and
bolts 48, but such securing could be effected by a weld. The bends
in the mounting plate 43 are merely to accommodate same to the
curved shape of the lower surface of the seat portion 11.
The bridge member 34 and the crossrods 18 and 23 comprise a rigid
crossbar means whereby the legs 19, 20, 24 and 25 are secured to
the mounting plate 43.
The bridge member 51, illustrated in FIG. 6, is comprised of a pair
of channel members 52 and 53 having webs 54 and 55, respectively.
The flanges 56 and 57 of channel member 52 are preferably spaced an
appropriate distance from the flanges 58 and 59, respectively, of
the channel member 53 when their respective webs 54 and 55 are
bearing against diametrically opposite sides of the crossrods 18A
and 23A. Thus, the channel members 52 and 53 can be secured to each
other and, at the same time, secured to the crossrods 18A and 23A
by two lines of welding on opposite sides of the bridge member 51.
There may be occasions when this form of structure would be
desirable to improve strength or achieve the same strength with
slightly lighter gauge materials.
Moreover, there may be circumstances where the central portions of
the crossrods can be omitted so that the upper ends of the legs are
integral with small pieces of rod which are secured within the
opposite ends of the bridge member 51.
The bolt 63, which secures the bridge member 51 to the mounting
plate 43A, is slidably received through a spacer 64 located between
the webs 54 and 55, and said bolt is engaged at its lower end by a
nut 65. In all other respects, a chair having the bridge member 51
could, and preferably would, be identical with a chair having the
bridge member 34.
FIG. 7 illustrates three chairs embodying the invention and
arranged in stacked positions. It will be seen that the legs of an
upper chair are readily nestable with the legs of a lower chair and
the combination of the sloped back of the chair and the forward
stepping of the legs thereof, relative to the chair below it,
avoids interference between the seat and back portions. FIG. 8
merely illustrates that the legs of the nested chairs will be
substantially coplanar, as will be their runners.
FIG. 9 illustrates that an elongated base structure 71, which is
substantially the same, except for width, as the base structure 15
described above with respect to FIG. 2, can be used to support a
seat structure 72 which is also laterally elongated to accommodate
more than one occupant. However, the same minimizing of the adverse
affects of stress and strain and deflection upon the welds is
retained and such elongated seat and base structure is still
nestable. It will be readily apparent that other variations can be
furnished, including the variation in which two seat and back
combinations, as shown in FIG. 1, are placed upon the elongated
base structure of FIG. 9, and such an arrangement would not affect
the nesting features of this basic design.
OPERATION
Although persons skilled in this art will readily understand the
operation of the structures disclosed above from such disclosure,
the operation thereof is briefly summarized hereinafter for the
sake of convenience. A chair 10 (FIG. 1), built as described above,
can be occupied by children or adults in the same manner as a chair
having a similar occupant engaging portion, but having an entirely
conventional base or support structure. However, the runners 29 and
33 provide a much larger area for engagement with a supporting
surface, thereby substantially reducing the pressure per unit area.
This prevents harmful compression of carpet pile, dimpling of
relatively soft surfaces, such as vinyl tile, and scratches on
wooden surfaces, all of which are notorious problems created by
conventional, four-legged chairs.
While the support elements 16 and 17 are relatively rigid, they
have sufficient resilient flexibility that, for example, the
crossrods 18 and 23 will tend to flex as the occupant in the chair
leans frontwardly or rearwardly. This will tend to reduce fatigue
experienced in using a conventional four-legged chair in which such
deflections are virtually nonexistent. Such deflections of the
crossrods can be permitted because the lower ends of the legs are
securely anchored together. The extents and locations of the
runners 29 and 33 cause the chair 10 to resist backward
tipping.
Because the support structure 15 can be attached to the mounting
plate by means of two or more nut and bolt combinations, and
because the mounting plate 43 is secured to the seat 11 by four cap
screws, base structures 15 can be stocked in stacked arrangements
which require relatively little space for immediate attachment to a
wide variety of the occupant engaging portions, including a seat,
back and cushion. This permits decorator use of fabrics and colors
in relatively small quantities without losing the advantages of
large-scale production efficiency in the manufacture of the base
structures.
Although a particular preferred embodiment of the invention has
been disclosed in detail for illustrative purposes, it will be
recognized that variations or modifications of the disclosed
apparatus, including the rearrangement of parts, lie within the
scope of the present invention.
* * * * *