US3594041A

US3594041A - Reverse cantilevered tubular chair

Info

Publication number: US3594041A
Application number: US848824A
Authority: US
Inventors: Ralph K Rye
Original assignee: Individual
Current assignee: Individual
Priority date: 1969-08-11
Filing date: 1969-08-11
Publication date: 1971-07-20
Anticipated expiration: 1988-07-20

Abstract

A two-part, tubular chair having a cantilevered seat that is supported at the rear of the chair. The chair base frame is formed from two tubular members, one positioned within the other, which are bent together to provide sufficient structural strength to prevent deflection of the reverse cantilevered seat section A tubular back frame having a back rest member is removably secured to the base frame to complete the chair structure.

Description

United States Patent lnventor Ralph K. Rye

102 Bellevue Road, Swampscott, Mass. 01907 Appl. No. 848,824

Filed Aug. 11, 1969 Patented July 20, 1971 REVERSE CANTILEVERED TUBULAR Cl-IAlR 8 Claims, 7 Drawing Figs.

US. Cl 297/445, 297/450 Int. Cl A47c 7/00, A47c 7/14 Field of Search 297/239,

[56] References Cited UNITED STATES PATENTS 1,993,601 3/1935 Goldberg 297/239 2,457,294 12/1948 Wood 297/447 2,519,096 8/1950 Addition a. 297/447 Primary ExaminerCasmir A. Nunberg Attorney-Chittick, Pfund, Birch, Samu'els & Gauthier ABSTRACT: A two-part, tubular chair having a cantilevered seat that is supported at the rear of the chair. The chair base frame is formed from two tubular members, one positioned within the other, which are bent together to provide sufficient structural strength to prevent deflection of the reverse cantilevered seat section A tubular back frame having a back rest member is removably secured to the base frame to complete the chair structure.

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Fig.4

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PATENTEB JUL20 I971 sum 2 OF 2 INVENTOR K p K- Rye m4 BM Luv 4 okra/dug REVERSE CANTILEVERED TUBULAR CHAIR BACKGROUND OF THE INVENTION This invention relates to the design and manufacture of chairs in general and, more particularly, to a reverse cantilevered, tubular chair in which the seat cantilevers forward from the rear legs of the chair.

In the manufacture of tubular chairs, it is important to provide a chair construction that maintains the structural relationships of the chair components when the chair is subjected to the loading imposed by the weight of the occupant of the chair. If the tubular frame bends or gives too much, the result ing change in structural relationships will severely impair the designed comfort of the chair. The problem of structural deflection in a tubular chair construction is even more critical in the case of chairs having a cantilevered seat.

It is accordingly, a general object of the present invention to provide a cantilevered tubular chair construction having sufficient strength to maintain its designed configuration under loading.

It is a specific object of the present invention to provide a two-part, reverse cantilevered tubular chair construction.

It is another object of the present invention to provide a reverse cantilevered, tubular chair construction in which the chair base frame is formed from two tubular members, one positioned within the other, which are bent together to produce a continuous chair base frame.

It is still another object of the present invention to provide a two-part, reverse cantilevered tubular chair construction that can be easily fabricated and, thereafter, assembled without requiring special tools, adhesives or other fastening devices to maintain the two chair components in fixed relation.

These objects and other objects and features of the invention will best be understood from the following detailed description of a preferred embodiment, selected for purposes of illustration, and shown in the accompanying drawings in which:

FIG. 1 is a view in front elevation of a reverse cantilevered chair constructed in accordance with the present invention;

FIG. 2 is a view in side elevation of the chair;

FIG. 3 is a plan view ofthe chair;

FIG. 4 is a view in cross section taken along line M in FIG. 1 showing the U-shaped configuration of the chair base frame;

FIG. 5 is a view in cross section taken along line in FIG. 3, with the seat and backrest members removed, showing the assembled relationship of the chair base frame and the chair back frame;

FIG. 6 is a view in cross section taken along line libb in FIG. 2 showing the fastening of the base frame arm section to the back frame; and,

FIG. 7 is a front elevation of an alternative baclt frame construction.

Turning now to the drawings and particularly to FIGS. 1 through 5 thereof, there is shown in varying views a two-part, tubular, reverse cantilevered chair constructed in accordance with the, present invention and indicated generally by the reference numeral 10. The reverse cantilevered chair W has two major structural elements: a base frame and a back frame indicated generally by the reference numerals i2 and 14, respectively, in FIG. ll. These two frames, when assembled as shown in FIGS. 1 through 4, support a seat member 16 and backrest member 18. Specific details concerning the materials and assembly of the seat and backrest members will be described below after first discussing the construction and configuration of the base frame 12 and the back frame M.

In the preferred embodiment of the invention, the chair base frame 12 is formed from two tubular members with one member positioned within the other. The two tubular members are then bent together as a unit to produce a continuous structural element which defines the chair base frame 12. Looking at FIG. 5, it can be seen that the base frame 12 comprises two tubular members, an outer tubular member or tube 20 and an inner tubular member or tube 22 which extends beyond the end of the outer tube 20. A corresponding portion of the inner tube 22 also projects beyond the end of the outer tube 20 at the left-hand side of the chair base frame 12 as viewed in FIG. 3. The extended portion 22a of the inner tube 22 mates with and frictionally engages the inner wall of the tubular back frame 14.

The two

coaxial tubes

20 and 22 are bent together as a single unit to form the chair base frame 12. For purposes of identification, the continuous chair base frame 12 can be divided into the following sections: a rearwardly opening, U- shaped support section 24 (FIG. 4) with vertically extending back legs sections 26 and 28 (FIGS. ll, 2 and 5) which turn forwardly to form substantially horizontal arm sections 30 and 32 (FIGS. 2, 3 and 5) which, at the forward ends, curve downwardly and then backwardly to form substantially horizontal seat supports sections 34 and 36 (FIGS. 2 and 5) which terminate in the extended end portions 22a of the inner tube 22. The U-shaped support section 24 can also be subdivided sectionally into two horizontal forwardly extended leg sections 24a and 24b which are held in spaced, coplanar relation by the transverse bar 240 of the U-shaped section.

It will be appreciated that the transverse bar 24c can per form its function of maintaining the chair base frame legs 24a and 24b in spaced, coplanar relation in positions other than at the front of the chair. For example, if the chair base frame 12 is formed from two sets of coaxial tubes with each set having a forwardly extending leg section, a vertically extending back leg section, a horizontal arm section and a substantially horizontal seat support section, the transverse brace or bar 24c can be positioned at the back of the horizontal leg section so that the Ushaped base support section 24 opens in a forward direction. Other configurations for the transverse bracing such as H" and X" members can be used if the chair base frame is formed from two sets of the coaxial tubular members. However, in the preferred embodiment of the invention, the single, continuous coaxial tubular element is used to form the backwardly opening U-shaped support section and corresponding vertical leg sections, horizontal arm sections and seat sections.

The coaxial, double-tube construction of the chair base frame 12 is required for the reverse cantilevered chair of the present invention in order to prevent undesirable deflection of the chair frame under the weight of the occupant. It has been found by experimentation that a single-tube base frame having the same configuration as shown in FIGS. I through 5 does not have sufficient strength to prevent the frame from bending forwardly. The deflection occurs in the single tube construc tion because the bending and pulling of the frame takes place in the straight portions of the frame as well as in the curves, thus allowing the seat to dip forwardly beyond the point of comfort for the occupant. Using a standard size single steel tubing, such as, a lowcarbon steel tube, either welded or seamless, having an outer diameter of 1 inch, the deflection could not be overcome by employing a thicker walled tube.

The problem of frame deflection in the reverse cantilevered chair construction was solved by reinforcing the conventional steel tubing with an inner steel tube of much lighter weight and smaller diameter. A reverse cantilevered chair base frame ll2 was constructed from standard, low-carbon steel tubing using an outer tube of 14 gage, l-inch outside diameter and 22 gage inner tube having a 13/ l 6-inch outer diameter. The inner tube 22 was positioned within the outer tube 20 with a snug fit prior to bending. The two tubes, after being assembled in coaxial relation to form a single continuous element, were then bent together as a unit into the configuration shown in FIGS. 1 through 5. As the two tubes were bent together, the inner steel tube 22 stretched thereby tensioning the outer steel tube 20. Since the inner steel tube was bent inside of the outside steel tube, crushing and distortion at the bends on the exterior surface was reduced while the inside tube distorted and wrinkled to give added internal strength. The resulting doubletube base frame 12 was stiff and had very little deflection and it provided more than enough added strength to overcome the unwanted deflection encountered with the single construction. However, it should be understood at this point that the type of material, the diameters and gages of the tubing used in the above example are by way of illustration only and should not be construed as limiting with respect to the reverse cantilevered chair construction of the present invention.

The second major structural element of the reverse cantilevered chair, i.e., the back frame I4, is illustrated in FIGS. 1, 2, 3, and partially shown in FIGS. 5 and 6. In the preferred embodiment, the back frame I4 comprises a single tube which is bent to form two downwardly and forwardly depending

side sections

38 and 40 which are held in spaced and fixed relation by a transverse back section 42. Looking at FIG. 5, it can be seen that the forwardly extending portions of the

side sections

38 and 40 slide over and are held in frictional engagement with the extended portions 220 of the chair base frame inner tube 22. The entire back frame, including the downwardly depending and forwardly extending

side sections

38 and 40, is located inwardly of the chair base

frame arm sections

30 and 32 and can best be seen in FIGS. 1, 2, 3 and 5. Although this location is preferred, the side sections of the back frame can be located on the outside of the chair base frame arm sections without departing from the scope of the invention.

The seat and

backrest members

16 and 18, respectively, can be formed from any suitable material, such as, for example, fabric, leather or plastic. The use of a flexible material for the seat and backrest members is preferred because it allows these members to be slid over the

seat support sections

34 and 36 and the back frames

side sections

38 and 40, respectively. However, it should be understood that the seat and

backrest members

16 and 18 can be formed from a relatively rigid material, such as, wood, plastic or metal and then hung from or otherwise secured to the appropriate seat support and back frame side sections.

Turning now to FIGS. 5 and 6, the preferred embodiment of the invention utilizes a fastening means between the substantially horizontal ann sections of the base frame and the downwardly depending side sections of the back frame. As shown in FIG. 6, the fastening means comprises a pin 44 which is threadably secured to the ann section of the outer and

inner tubes

20 and 22. Each back frame side section has an aperture 46 to receive the pin 44 in frictional engatement. A corresponding aperture 48 is provided in both sides of the back rest member 18 at a point that will line up with the pin 44 and back frame aperture 46 when the backrest member is positioned on the back frame as shown in FIGS. ll, 2 and 3.

The pins 44 keep the material of the backrest member 18 in place and in doing so eliminate the chance of the back frame and arm rattling where they cross. The pins also serve to exactly position the two chair frame parts and, when weight is applied to the seat, the pins transfer the pressure to the back legs. The pressure transfer keeps the seat from sagging and changing the comfort angles of the seat and back. This construction eliminates the chance that over a long period of use the bend at the front where the arm and seat support sections flow together will not stretch out causing permanent changes in the angles of seating for comfort.

FIG. 7 illustrates an alternative construction in which the backrest member 18 is secured to the back

frame side sections

38 and 40 by means of a plurality of braces as and corresponding suitable fasteners 52. In this configuration, the combination of the back rest and braces serves the dual pur pose of holding the

side sections

38 and 40 in the desired position and at the same time, provides a support for the chair occupants back.

The combined back frame-backrest construction shown in FIG. 7 can also be employed in another embodiment of the invention. It has already been mentioned that the chair base frame 12 can be formed from two'sets of coaxial tubes and a transverse brace to maintain the horizontal leg sections in spaced, coplanar relation. Since the combined back framebackrcst construction shown in FIG. 7 performs the same function as the back frame transverse bar 42, i.e., holds the

side sections

38 and 40 in spaced, fixed relation, it will be appreciated that if the base frame is formed from two sets of coaxial tubes, the sets can be extended in length enough to form the

upstanding side sections

38 and 40 as a continuous structural element. In this embodiment, the reverse cantilevered chair I0 has a chair frame comprising two sets of coaxial tubes with each set having a forwardly extending leg section, a vertically extending back leg section, a substantially horizontal arm section, a substantially horizontal seat support section and a vertically extending side section. The two sets of bent coaxial tubes are held in spaced relation by suitable means, such as, the transverse brace 24c between the two forwardly extending leg sections and by means positioned between and secured to the two vertically extending

side sections

38 and 40, such as, the transverse bar 42 or the combined back frame-backrest construction shown in FIG. 7.

Having described in detail the preferred embodiment of my invention, what I claim and desire to secure by Letters Patent of the United States is:

I. A reverse cantilevered, tubular chair comprising:

a chair frame formed from two tubular elements, each tubular element comprising two tubular members, one posi tioned within the other, said chair frame tubular elements each being bent into a forwardly extending horizontal leg section which turns upwardly at the rear to form a vertically extending back leg section which turns forwardly at the upper end thereof to form a substantially horizontal arm section which, at the forward end thereof, curves downwardly and then backwardly to form a substantially horizontal seat support section and finally turns upwardly to form a substantially vertical side section;

means for maintaining said chair frame forwardly extending, horizontal legs sections in spaced, coplanar relation;

means for maintaining said upwardly extending, substantially vertical side sections in spaced, fixed relation; and,

a seat member mounted between said seat support sections 2. A reverse cantilevered, tubular chair comprising:

a base frame formed from two tubular elements, each tubular element comprising two tubular members, one positioned within the other, with the inner tubular member being longer than and extending beyond one end of the other tubular member, said base frame tubular elements each being bent into a forwardly extending horizontal leg section which turns upwardly at the rear to form a vertically extending back leg section which turns forwardly at the upper end thereof to form a substantially horizontal arm section which, at the forward end thereof, curves downwardly and then backwardly to form a substantially horizontal seat support section which terminates in the extended portion of the inner tubular member;

means for maintaining said base frame forwardly extending,

horizontal legs sections in spaced, coplanar relation;

a back frame comprising: two tubular side members fitted over the extended portions of said base frame inner tubular members, said side members extending backwardly and upwardly, and means for maintaining the upwardly extending portions of said side members in fixed, spaced relation; and,

a seat member mounted between and removably secured to said seat support sections.

3. The chair of claim 2 further characterized by said means for maintaining the upwardly extending portions of said side members in fixed, spaced relation including a backrest member.

4. A reverse cantilevered, tubular chair comprising:

a base frame formed from two tubular elements, each tubular element comprising two tubular members, one positioned within the other, with the inner tubular member being longer than and extending beyond one end of the other tubular member, said base frame tubular elements each being bent into a forwardly extending horizontal leg section which turns upwardly at the rear to form a vertically extending back leg section which turns forwardly at the upper end thereof to form a substantially horizontal arm section which, at the forward end thereof, curves downwardly and then backwardly to form a substantially horizontal arm section which, at the forward end thereof, curves downwardly and then backwardly to form a substantially horizontal seat support section which terminates in the extended portion of the inner tubular member;

means for maintaining said base frame forwardly extending,

horizontal legs sections in spaced, coplanar relation;

a tubular back frame having a substantially horizontal transverse back section and two downwardly and forwardly depending side sections, said side sections being fitted over the extended portions of said base frame inner tubular members;

a seat member mounted between and removably secured to said seat support sections; and,

a backrest member mounted between and removably secured to said back frame side sections.

5. The chair of claim 4 further characterized by means for fastening the downwardly depending side sections of said back frame to arm sections.

6. A reverse cantilevered, tubular chair comprising: a base frame formed from two tubular members, one positioned within the other, with the inner tubular member being longer than and extending at each end beyond the outer tubular member, said base frame having a rearwardly opening, U-shaped support section with vertically extending back leg sections which turn forwardly to form substantially horizontal arm sections which, at the for-,

ward ends thereof, curve downwardly and then backwardly to form substantially horizontal seat support sections which terminate in the extended portions of said inner tubular member;

a tubular back frame having a substantially horizontal transverse back section and two downwardly and forwardly depending side sections, said side sections being fitted over the extended portions of said base frame inner tubular member;

7. The chair of claim 6 further characterized by means for fastening said downwardly depending side sections of said back frame to said arm sections.

8. The chair of claim 7 further characterized by said back frame side sections being located inwardly from said base frame arm sections.

Claims

1. A reverse cantilevered, tubular chair comprising: a chair frame formed from two tubular elements, each tubular element comprising two tubular members, one positioned within the other, said chair frame tubular elements each being bent into a forwardly extending horizontal leg section which turns upwardly at the rear to form a vertically extending back leg section which turns forwardly at the upper end thereof to form a substantially horizontal arm section which, at the forward end thereof, curves downwardly and then backwardly to form a substantially horizontal seat support section and finally turns upwardly to form a substantially vertical side section; means for maintaining said chair frame forwardly extending, horizontal legs sections in spaced, coplanar relation; means for maintaining said upwardly extending, substantially vertical side sections in spaced, fixed relation; and, a seat member mounted between said seat support sections

2. A reverse cantilevered, tubular chair comprising: a base frame formed from two tubular elements, each tubular element comprising two tubular members, one positioned within the other, with the inner tubular member being longeR than and extending beyond one end of the other tubular member, said base frame tubular elements each being bent into a forwardly extending horizontal leg section which turns upwardly at the rear to form a vertically extending back leg section which turns forwardly at the upper end thereof to form a substantially horizontal arm section which, at the forward end thereof, curves downwardly and then backwardly to form a substantially horizontal seat support section which terminates in the extended portion of the inner tubular member; means for maintaining said base frame forwardly extending, horizontal legs sections in spaced, coplanar relation; a back frame comprising: two tubular side members fitted over the extended portions of said base frame inner tubular members, said side members extending backwardly and upwardly, and means for maintaining the upwardly extending portions of said side members in fixed, spaced relation; and, a seat member mounted between and removably secured to said seat support sections.

4. A reverse cantilevered, tubular chair comprising: a base frame formed from two tubular elements, each tubular element comprising two tubular members, one positioned within the other, with the inner tubular member being longer than and extending beyond one end of the other tubular member, said base frame tubular elements each being bent into a forwardly extending horizontal leg section which turns upwardly at the rear to form a vertically extending back leg section which turns forwardly at the upper end thereof to form a substantially horizontal arm section which, at the forward end thereof, curves downwardly and then backwardly to form a substantially horizontal arm section which, at the forward end thereof, curves downwardly and then backwardly to form a substantially horizontal seat support section which terminates in the extended portion of the inner tubular member; means for maintaining said base frame forwardly extending, horizontal legs sections in spaced, coplanar relation; a tubular back frame having a substantially horizontal transverse back section and two downwardly and forwardly depending side sections, said side sections being fitted over the extended portions of said base frame inner tubular members; a seat member mounted between and removably secured to said seat support sections; and, a backrest member mounted between and removably secured to said back frame side sections.

6. A reverse cantilevered, tubular chair comprising: a base frame formed from two tubular members, one positioned within the other, with the inner tubular member being longer than and extending at each end beyond the outer tubular member, said base frame having a rearwardly opening, U-shaped support section with vertically extending back leg sections which turn forwardly to form substantially horizontal arm sections which, at the forward ends thereof, curve downwardly and then backwardly to form substantially horizontal seat support sections which terminate in the extended portions of said inner tubular member; a tubular back frame having a substantially horizontal transverse back section and two downwardly and forwardly depending side sections, said side sections being fitted over the extended portions of said base frame inner tubular member; a seat member mounted between and removably secured to said seat support sections; and, a backrest member mounted between and removably secured to said back frame side sections.