US3131904A

US3131904A - Tilting chair construction

Info

Publication number: US3131904A
Application number: US126643A
Authority: US
Inventors: Lie Finn
Original assignee: Individual
Current assignee: Individual
Priority date: 1961-07-25
Filing date: 1961-07-25
Publication date: 1964-05-05
Anticipated expiration: 1981-05-05
Also published as: CA737268A

Description

May 5, 1964 F. LIE 3,131,904

TILTING CHAIR CONSTRUCTION Filed July 25, 1961 2 Sheets-Sheet 1 5 7 .32 4 3 46 I 56 42 2: I 1 I rev 5 L l r92 i 104 90 3 40 42 76 76 40 9 34 INVENTOR. F/G. 3 F/NN L/E ,47'TOENE V5 May 5, 1964 F. LIE

TILTING CHAIR CONSTRUCTION 2 Sheets-Sheet 2 Filed July 25, 1961 BY MLso/v, 557715 & CRAIG mu 6 m F z w a w L w 1% E w fl W fi /flz I,

ArrozA/E Y5 United States Patent 3,131,904 TILTING CHAIR CONSTRUCTION Finn Lie, Ring ti ration, near Hamar, Norway Filed July 25, 1961, Ser. No. 126,643 4 Ciairns. (Cl. 248-373) This invention relates to tilting chair constructions, as for example, ofiice chairs, and more particularly to an iron for a tilting chair that utilizes a torsion bar for resiliently restraining the backward tilting of a chair seat as a person, sitting in the chair, shifts his weight to tilt the seat back. V

A great many of the tilting chair iron constructions of the prior art have utilized heavy castings and coil springs in their construction. The coil springs are bulky and require sockets of appreciable size to retain their ends. Further, in order to adjust the tension of the springs, controlling the tilting movement of the chair, an adjusting mechanism of some sort, usually comprising a yoke and threaded handle spring tensioner assembly, has been required. The sum total of these requirements have found the prior art products to be of substantial bulk and characterized by various knobs, springs, plates, sockets, etc., which require an extended assembly time, generally resulting in a large unit, lacking in aesthetic appeal for consumers.

Accordingly, it is an important object of the present invention to provide a novel, tiltable chair iron' utilizing a torsion bar to provide a resilient restraining force for the tilting movement of the chair seat, as a neat, precise and compact unit.

Another object is to provide a tiltable chair iron which utilizes stamped parts in its construction, that are readily assembled with a minimum amount of labor, and that has long life substantially free of maintenance.

A further object is to provide a tiltable chair iron uti1iz ing a torsion bar wherein the two ends of the torsion bar are provided with stops whereby the parts bearing against the torsion bar are not secured to the torsion bar, thus substantially reducing the assembly time of the unit.

A further object is to provide a tiltable chair iron utilizing a torsion bar wherein a spindle socket support mounted on the torsion bar cooperates with a seat frame support to establish the pivotal limits of movement of the chair seat which is mounted upon the assembly.

A still further object is to provide a tiltable chair iron utilizing a torsion bar wherein a simple tensioning arm of neat appearance is interposed between one end of the torsion bar and a seat support to provide adjustment of the tension of the torsion barand thereby adapt the chair to use by occupants of differing weight.

Other objects of this invention will appear in the following description and appended claims, reference being had to the accompanying drawings forming a part of this specification wherein like reference characters designate corresponding parts in the several views.

- In the drawings:

- FIG. 1 is an elevational view of a chair incorporating an iron made in accordance with the present invention;

FIG. 2 is a bottom plan view of the present chair iron construction; i

FIG. 3 is a front view, partially in section, taken along the lines 33 of FIG. 2, loohng in the direction of the arrows; V

FIG. 4 is a section view taken along the line 44 of FIG. 2, looking in the direction of the arrows;

FIG. 5 is a side elevational view of FIG. 2, taken along line.55 of FIG. 2; and

FIG. 6 is a section view taken along the line 66 of FIG. 2, looking in the direction of the arrows. if

Before explaining the present invention in detail it is ice to be understood that the invention is not limited in its application to the details of construction and arrangement of parts illustrated in the accompanying drawings, since the invention is capable of other embodiments and of being practiced or carried out in various ways. Also, it is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation.

Briefly the present invention relates to a new and improved tilting chair iron construction that utilizes a pair of spaced seat supports that are carried by a pair of aligned frame tubes, spaced at their inner ends by a separator carrying a stop member. A torsion bar tube is positioned within the frametubes in rotatable relation and a torsion bar is positioned coaxially within thelatter tube. The torsion bar is connected at one end to one end of the torsion bar tube and extends the combined length of the frame tubes. An adjustable tensioning arm is connected to the other end of the torsion bar and is provided with a stop adapted to engage one of the seat supports.

A spindlesocket support is rotatably mounted on the torsion b'ar tube within the separator for the frame tubes and is provided with an abutment to engage an abutment on a torsion bar tube. Also, the spindle socket support is provided with stops which establish the limits of tilting movement of the seat" supports.

Thus pivoting of the seat support and frame tubes about the torsion bar tube is effective to move the tensioning arm and thus impart a-twist to the torsion bar that biases the torsion bar tube more firmly against the immovable spindle socket support to provide a resilient pivoting support 'of thechair seat and engagement of the chair seat stop member with the spindle socket support stops to establish the limits of movement of the chair seat.

THE ENVIRONMENT As shown in FIG. 1, a chair structure, utilizing a torsion bar iron of the present invention, includes a floor engaging base 10 having outwardly extending legs 12 supported at their lower terminal ends by rollers 14 for moving the unit about. Centrally of the base 10 there is provided a vertically disposed spindle 16 having an exposed upper end of tapered configuration (not'shown). The upper end of the spindle projects into a tapered socket 18 which is a part of the central support assembly 20,-FIG. 2, of the chair iron 22. A chair seat 24 is mounted upon the iron 22 for rearward pivotal movement against resiliently restraining forces imparted by a torsion bar, to be subsequently described, which forms a component part of the iron. Arms 26 and a back 28 of suitable configuration are mounted on the seat 24 in a conventional manner to complete the chair structure.

I THE NOVEL IRON As shown in the detailed views of FIGS. 2-6, the iron 22 includes a pair of spaced seat-supporting angles 30,

each having a vertically disposed leg 32 and a horizontally disposed leg 34. The horizontally disposed legs 34 are provided with apertures as.at 36, suitably formed by drilling, punching or the like, through which bolts or other suitable fastening devices (not shown) can be passed for connection with a chair seat 24, previously FIGS. 2 and 3, assembly of the unit is such that the spaced, seat-supporting angles 30 are in aligned relationship.

Centrally of the spaced seat-supporting angles 30, there is provided a generally square spacer and stop member 44 having vertically disposed sides 46, a vertically disposed front 48 anda vertically disposed back 50. The sides 46, front 48 and back 50 are suitably fabricated from one piece of strap steel of rectangular cross section, as indicated in'FlG. 3, the ends of the strap being joined as by welding (not shown) after formation of the unit 44 is completed. As best shown in FIG. 4, a portionof the vertically disposed back 50, in the centralpart thereof, is turned back' from the top to provide a stop lip 52, that is fitted with aresilient stop cushion 54, suitably formed of nylon. The metal of the vertically disposed back 50, remaining beneath the stop lip 52, is bowed outwardly as indicated at 56 to stiffen the stop lip 52. v The vertically disposed sides 46 are provided with apertures 58 adapted to receive the inner ends of. the support tubes 40, which arewelded as'at 42,: to provide a rigid assembly made up of the spaced, seat-supporting angles 30, the support tubes 40 and the square spacer and stop member 44. This assembly supports a chair seat24 and cooperates with a torsion bar unit carried withinthe support tubes 40 to resiliently restrain tilting movement ofthe. chain seat between a horizontal 1 position and a tilted position. v a

Theiron also includes the p'erviou'sly mentioned central support. assembly'20 that, as best shown in .FIGS. 4

and 6, comprises a lower U-shaped yoke 60 having vertically disposed arms 62, and an upper U-shaped yoke64 having .verticallvdisp sed arms 66 fitting in adjacent relationship inside of the arms'62. Riverts 68 are inserted through aligned apertures formed in the arms 62 .and 66 to secure the' assembly. The previously mentioned tapered socket 18 is fitted into

suitable apertures

70 and 72 formed in the lower yoke 60 and the upperyoke 64 and is fastened in position by tack welding or the equivalent, as shown at 74 in FIG. 4.

As shown in FIG. .4; the vertically disposed arms 62 of the lower U-shaped yoke 60 extend rearwardly in the shape of enlarged supporting tabs 76, also shown in FIG. 2. The support tabs 76 are provided with apertures 78 in aligned relationship asshown in FIG. 2, and an elongated tube 80 is passed therethrough and within support tubes 40, enough clearance being provided to permit free rotation. As best shown in FIG. 4 a key 82.isinserted in secured relationship into a suitable aperture; provided in the tnbe80l Also, as shown in FIG. 4, the upper U- shaped yoke 64 extends rearwardly as an abutment tab 85 which is aligned with the key82, to be engaged thereby'and'thus' absorb tube thrust and transmit the thrust into the central support assembly 20, tapered socket '18, the chair spindle, the chair base, etc., thus to the surface upon which the chair rests. This configuration of parts permits assemblywithout welding.

When the parts are assembled, as shown in FIG. 4, the stop lip 52, previously mentioned, projects between the underside of the upper, U-shaped'yoke 64 and the upper surface. of, the lower, U-shaped yoke-60. This provides upper and lower stop limitsfortilting movement of the chair seat.

1 As best shown in'FIG, 3,1the tube: 80 has substantially the same length as the distance between the terminal ends of the tubes 40 but is positioned to extend outwardly from the left end of the left tube. 40, so thatthe right end lies at a point 86, whichisa short distance inside of the right end of the right tube 40. The left end of the tube" 80 is plugged and the plug is provided centrally with a square opening 88 into which the terminal end of a square torsion bar 90 is fastened.

The torsion bar90 extends the full length of the inner,

elongated "tube 80, as well as the full length of the outer support "tubes 40 and projectsya short distance beyond t r ht hand end, of the 'righthandtube 40 o provide a shoft connecting portion 92.

As best shown in FIGS. 2 and 5, a tensioning arm 94 is provided at its rear end with a circular bushing portion 96, having a square hole formed centrally thereof for receiving the right hand end of the torsion bar 90, including the short connecting portion 92. The circular bushing portion 96 has an outside diameter slightly less than the inside diameter of the tube 40 and thus is supported in rotatable, journaled relationship therein. The front end of the tensioning arm 94 is provided with a horizontally disposed tab portion 98 provided with a threaded aperture, adapted to receive the threaded end 100 of an adjusting or tensioning crank 102. The threaded end 100 of the tensioning crank 102 terminates in a contacting ball portion 104, FIGS. 3 and 5, that abuts the underside of the horizontally disposed leg 34 of the right support angle 30. The other end of the crank '102 takes the form of-an offset arm 105 having a knob 106 fastened thereto.

, FUNCTION OF THE APPARATUS support assembly 20 and the arms 76 thereof also em brace the elongated tube 80 to support the tube in space. Thus, the vmechanism including the square spacer. and stop member 44, support. tubes 40 and angles are supported in space to support the chair seat.

When, as shown in FIGS. 4 and 5, a personoccupies V the chairand tilts the rear portion of the seat downwardly and rearwardly, two actions take place. 'The first action 1 is the pressing-of the horizontal leg 34 of the right support angle 30 against the contact portion 104 of the crank 102 to carry the tensioning arm 94 downwardly, causing the torsion bar 90 to be twisted, thus turning the elongated tube 80 and forcing the key 82 into tighter engagement 1 with the abutment tab 84, which is immovable, thus providing a resilient, restraining action for the downward tilting of the chair seat. During the downward and rearward tiltingof the chair seat, the stop lip.52, carrying the resilient stop cushion 54, moves from contacting relationship with the underside of the upper, U-shaped' yoke ADJUSTABILITY FEATURE By means of the tensioning crank 102, the resilient restraining force provided by the torsion bar 90 can .be adjusted. Thus, as shown in FIG. 5, turning the'crank 102 to move the horizontal tab portion 98, of the, tensioning arm 94 upwardly will have the efiectof reducing the pretwist'imparted to the torsion bar 90 and thus will permitthe chair to be tilted with less weight or'force.

' On the other hand, adjusting the crank 102 to pull the tensioning arm 94 downwardly will serve to impart a greater pretwist to the torsion'bari90 and accordingly 2. larger weight or force be required to move the chair seat downwardly in a tilting manner. adapted to use by persons of different weight. i

MATERIALS OF CONSTRUCTION u The stampings utilized in the present constructionwill be formed of steel as will the support tubesf Also, the spindle. socket will be made of steel. The torsion bar will be made of steel of a suitable resiliency. to provide a supportingstructure and will be of a metal which will resist torsionalbending throughout along lifetime. The tensioning arm maybe madeas a casting, forgi.ng,.ior stamping,- of suitable. steel. .The adjusting or tensioning crankwill be made of cold rolledsteel rod stock or the equivalent and the knob' of similar material. The re,

Thus the iron silient stop cushion 54 is suitably formed of nylon, as mentioned, although other resilient materials, such as rubber and plastics or synthetic resins of resiliency characteristics similar to nylon can be utilized.

SUMMARY In View of the foregoing it will be observed that an improved chair iron of the tilting type is provided that utilizes a torsion bar as a resilient restraining member, and that comprises a minimum number of parts, including simple stampings and tubing, readily and simply assembled with a minimum amount of labor, including only a small amount of Welding and a minor amount of riveting. Thus substantial manufacturing economies are provided for a clean, compact unit, characterized by long, trouble-free operation, substantially without maintenance.

I claim:

1. In a tilting chair iron, a seat support comprising two laterally spaced frame elements, a pair of support tubes, each of said tubes having one end connected to one of said frame elements, the other ends of said tubes being connected to a spacer with the tubes in axial alignment, said spacer being effective to space the other ends of said support tubes 2. short distance apart, a torsion bar tube positioned within said support tubes in rotatable relation therein, a spindle socket support rotatably mounted on said torsion bar tube within said spacer and between the other ends of said support tubes, a key in said torsion bar tube engageable with said spindle socket support, an elongated torsion bar within said torsion bar tube, said torsion bar being connected to said torsion bar tube at one point, and adjustable abutment means carried by said torsion bar and spaced from said one point and contactably engaging said seat support.

2. In a tilting chair iron, a cushion-supporting frame element, a support tube connected to said frame element, a stop connected to said support tube, a torsion bar tube positioned within said support tube in rotatable relation, a spindle socket support rotatably mounted on said torsion bar tube, first and second spaced abutments on said spindle socket support engageable with said support tube stop, means on said torsion bar tube engageable with said spindle socket support, a torsion bar within said torsion bar tube, means connecting a first point of said torsion bar to said torsion bar tube, and an arm connected to a second point on said torsion bar and freely engaging said frame element.

3. In a chair iron,

a seat support comprising two laterally spaced frame elements,

a pair of support tubes, each of said tubes having one end connected to one of said flame elements,

said tubes being positioned in coaxial alignment with the other end of each tube connected to a spacer,

said spacer being effective to separate the other ends of said support tubes,

a torsion bar tube extending within said support tubes in rotatable relation and spanning said spacer,

a spindle socket support rotatably mounted on said torsion bar tube within said spacer and between the other ends of said support tubes,

a key abutment on said torsion bar tube contactably engageable with said spindle socket support,

a torsion bar within said torsion bar tube,

said torsion bar being connected to said torsion bar tube at one end and projecting beyond the other end of said torsion bar tube to be exposed,

an arm rigidly connected at one end to said torsion bar exposed end,

an aperture in the other end of said arm,

and a threaded rod in said aperture and having one end engageable with one of said frame elements.

4. In a tilting chair iron,

a seat support comprising two laterally spaced frame angles,

first and second support tubes, each of said tubes having one end connected to one of said frame angles,

said tubes being positioned in coaxial alignment with the other ends of said tubes attached to a connector,

said connector being efiective to separate the other ends of said support tubes and provide a space therebetween,

a torsion bar tube positioned within said support tubes in rotatable relation therein,

a spindle socket support rotatably mounted on said torsion bar tube within said connector space, between the ends of said support tubes,

abutment means on said torsion bar tube contactably engageable with said spindle socket support,

spaced abutments on said spindle socket supports,

a stop lip formed on said connector and projecting between and engageable with said abutments,

an elongated torsion bar within said torsion bar tube, said torsion bar being connected to said torsion bar tube at one point,

and means carried by said torsion bar and spaced from said one point and contactably engaging a frame angle of said seat support.

References Cited in the file of this patent UNITED STATES PATENTS

Claims

1. IN A TILTING CHAIR IRON, A SEAT SUPPORT COMPRISING TWO LATERALLY SPACED FRAME ELEMENTS, A PAIR OF SUPPORT TUBES, EACH OF SAID TUBES HAVING ONE END CONNECTED TO ONE OF SAID FRAME ELEMENTS, THE OTHER ENDS OF SAID TUBES BEING CONNECTED TO A SPACER WITH THE TUBES IN AXIAL ALIGNMENT, SAID SPACER BEING EFFECTIVE TO SPACE THE OTHER ENDS OF SAID SUPPORT TUBES A SHORT DISTANCE APART, A TORSION BAR TUBE POSITIONED WITHIN SAID SUPPORT TUBES IN ROTATABLE RELATION THEREIN, A SPINDLE SOCKET SUPPORT ROTATABLY MOUNTED ON SAID TORSION BAR TUBE WITHIN SAID SPACER AND BETWEEN THE OTHER ENDS OF SAID SUPPORT TUBES, A KEY IN SAID TORSION BAR TUBE ENGAGEABLE WITH SAID SPINDLE SOCKET SUPPORT, AN ELONGATED TORSION BAR WITHIN SAID TORSION BAR TUBE, SAID TORSION BAR BEING CONNECTED TO SAID TORSION BAR TUBE AT ONE POINT, AND ADJUSTABLE ABUTMENT MEANS CARRIED BY SAID TORSION BAR AND SPACED FROM SAID ONE POINT AND CONTACTABLY ENGAGING SAID SEAT SUPPORT.