US2577089A

US2577089A - Adjustable back rest for chairs

Info

Publication number: US2577089A
Application number: US52503A
Authority: US
Inventors: Mondy Peter
Original assignee: Burroughs Adding Machine Co
Current assignee: Unisys Corp
Priority date: 1947-04-05
Filing date: 1948-10-02
Publication date: 1951-12-04
Anticipated expiration: 1968-12-04

Description

Dec. 4, 1951 MONDY 2,577,089

ADJUSTABLE BACK REST FOR CHAIRS Original Filed April 5, 1947 2 SHEETS-SHEET l IN VEN TOR.

Y Peter Mony Dec. 4, 1951 P. MONDY ADJUSTABLE BACK REST FOR CHAIRS Original Filed April 5, 1947 2 SHEETSSHEET 2 INVENTOR. PeTeP Nonciy mmm m 6 Wu 1 2 7 2 AL! 2 2 C 0 B Y 5 5 v B W 7 1 m =5 5 8 7 7 2 z 2 a 8 a I m m 1 ll'Fll 9 M 2 d- 12 $35 a H 1 Fig. 2.

Patented Dec. 4, 1951 UNITED stares ADJUSTABLEMBACK BEST FQB Ori inal appiication Apri 5, .1947; eri 1"No.. 739 553. Divided and this application (ictober My invention relates generally. to chairs-and has to do particularly with a tiltable back rest adjustably mounted on a back-supporting frame to provide maximum comfort for the: usercof' the chair.

Thisapplication is a division of m-y-coepending application, Serial No; 739,553, filed. April 5, 19147, for Adjustable .Chairr An object of my invention is to provide an improved chair of the,foregoing-character.

Another object is-to provide-an adjustable back rest for a chair which may be formed frorn a --re1 at ively small number of simple and inexpene sive parts with a minimum of: machined or closefitting'surfaces; and which-maybe assembled readily with a minimum of fitting or adjustment.

Another object is to. provide'a chair-having a simple and strong back-rest cushion supporting mechanism which may be readily adjusted to a convenient height by the user and which permits rocking movement of the back cushion on its support for increased comfort of the user as he shifts his position in the chair.

Other objects and advantages of-theinvention will appear from the following description taken in conjunction with the appended drawings,

wherein:

Figure 1 is a perspective view showing a chair constructed in accordance with my invention and with a portion of the tiltabl-e backrest cutaway showing one of its adjustable and pivotai support members;

in the base It, a seat I2 mounted on theseatsupporting post H and a back-supporting frame l3 extending upwardly at the rear of the seat! 2 for-adjustably supporting-a bracket-unit A. The bracket-unit A adapted to :pivotally support a tiltable back-rest cushion I4. at adjusted heights convenient to the user of the chair.

The back-rest support or back-supporting frame l3 (Fig. 2), preferably formed of a light cast metal such as aluminum, supports two rods l5 disposed in parallel relation and secured to .2 bosses. l3a: formed near the top and on the inside portion of the backesupporting frame Baby suitable fastening means, for example screwsuiii. Means is. carried on the rods i5 for supporting the back cushion Matadjusted heights relative to the back frame I13 and seat cushion I2 for maximum comfort of the user. This means comprises-a bracket lL'I disposed on the front side of each rod IS in slidable and adjusted clamped relation with its respective: supporting rod; The brackets i '1 are made integral with a cross-connecting bar I8 disposed transversely with andon the rear sideof the rods I 5, such as by a weld l-fla whereby the brackets are fixed 'tothe cross connesting bar It inspaced relation at points on the brackets inwardly from the rods- I5 to form the: slidable bracket-unit A. Each bracket H has arcuately shaped portions 19- co-eX-tensive with a portion of thefront surface of the rods l5, whereby-- the-brackets and cross-connecting bar I8 may be guided and maintained in fixed angular relation'with the rodsduring their adjusting movement therealong. An ear element 20 projectsoutwa-rdly from each bracket l1 and beyond the'rodsl5 and has a transverse opening adj acen-t-its end for freely receiving the threaded end of a knurled-headed thumb-screw2l. The threaded end of -the thumb-screw 2-! is threadedly received in the end of an ear- 22 provided by extending the cross-connecting bar [8 longitudinally in both directions to form areuate portions 22a (Fig. Bipartially encircling the rear-'side-of the rods [5' and terminating in the cars 22 which are disposed substantially parallel with the ears 2!! and spaced rearwardly therefrom. Each bracketil isprovided further with a forwardly directed arm *23 having a; transverse opening 24 adjacent its front end-tojournal a pivot stud 25 secured inan ear-formed on a bracket-plate 26. The bracket-plates 26 are provided at their tops and; bottoms with an elongated opening 251 adaptedto; receive suitable fastening means, for example screws 28', for fastening the bracket:- pla-te to a rear portion 29 of the. cushion l4; construction allows the back cushion I' l to, be locked at an adjusted height above the seat cushion l2 simply by tightening the thumbscrews 2| in the adjusted position ofthe, arcuate portions I'9and'22a along the rods l5 to cause these. ,arcuate portions to be securely clamped to th r ds and a ntain the cush on, liat'aselected height where it is free to move angularly relative to the back frame l3 on the pivot studs 25.

Means are provided for adjusting the angular position of the back-rest cushion I l relative to 3 the back-supporting frame l3, which includes rubber headed thumb-screws 30 carried in threaded collars 3| secured to the brackets 26. The brackets 26 are mounted on the back of the cushion M in a position so that the pivot studs 25 are located above the horizontal center line of the cushion l4 and the weight of the cushion below the said center line tends to maintain the cushion in a vertical position unless held otherwise out of this position by the rubber headed thumbscrews 3|] contacting in the channel portion of the back-supporting frame i3. A rubber stop 32 secured to the back-supporting frame l3 adjacent the top and on the front surface thereof is adapted to be contacted by the back 29 of the cushion if the said cushion is rotated counterclockwise (Fig. 2) a sufficient extent on its pivot studs 25.-

The length of the lugs 23 and the rubber stop 32 is such that both the height and tilting adjustments are accessible to the user of the chair without danger of pinching the fingers or hands regardless of the angular position of the cushion which making said adjustments.

While I have shown and described herein one form of structure embodying my invention, it will be understood that changes in details and ar-' rangements of parts may be resorted to without departing from the spirit of the invention.

I claim:

1. In a posture chair of the type having seatsupporting means and a back-supporting frame extending upwardly therefrom, the combination of a back rest mounting bracket unit having a rigid cross-bar and spaced arms extending forwardly therefrom, means supporting said mount ing bracket unit on said frame for vertical slidin adjustment thereon, a back rest, spaced pivot members rigidly secured to said back rest and pivotally journaled in said arms respectively for pivotally mounting said back rest on said mounting bracket unit and rearwardly extending bumper elements carried on said back rest and positioned to abut said frame to limit pivotal movement of said back rest in one direction.

2. In a posture chair having seat-supporting means and a back rest supporting frame extending upwardly therefrom, a back rest, a back rest mounting bracket unit having a rigid cross-bar and spaced arms extending forwardly therefrom, means for supporting said bracket unit in vertical slidable relationship on said supporting frame and comprising a plurality of spaced guides mounted on said frame, means for locking said mounting bracket unit to said guides in adjusted relationship thereon, a plurality of bracket elements rigidly mounted on the back of said back rest and having studs secured therein for pivotally supporting said back rest to said first mounting bracket unit, an adjustable resilient stop supported on said back rest below the pivot axis of said studs to limit the pivotal movement of said back rest in one direction, and a resilient stop secured to the said supporting frame above the pivot axis of said studs to limit the pivotal movement of said back rest in the other direction.

3. In a chair having a back-supporting frame, a back rest, means on said frame for adjustably and pivotally supporting a back rest, said means comprising spaced parallel rods having their ends secured to said frame, a bar extending transverse to and disposed on one side of said rods with the ends thereof projecting beyond said rods and having a threaded opening adjacent each of said projected ends, clamping elements integral with said bar and disposed on another side of said rods, each of said clamping elements having a first arm projecting therefrom, said first arm having an opening adjacent its end in axial alignment with the threaded opening in said bar, locking means disposed in said openings to clamp said clamping elements and said bar to said rods at selective positionsv along said rods, a second arm projecting forwardly from each of said clamping elements, brackets secured to the back of said back rest and supporting pivot elements journaled in said second arms respectively to pivotally support said back rest for angular movement relative to said frame, and an adjustable resilient stop supported on each of said brackets to limit the angular movement of said back rest in one direction and against said frame.

4. In a chair having a back-supporting frame, a back rest, spaced parallel elongate guides secured to said frame in vertically extending position and each spaced therefrom throughout a portion of its length, a bar extending transversely of said guides with the ends thereof projecting beyond said guides, clamping elements integral with said bar and disposed adjacent said guides, each of said clamping elements having a first arm projecting laterally therefrom in registry with the projecting ends of said bar respectively, locking means engaging said clamping elements and said bar to lock said bar on said guides at selected positions along said guides, a second arm projecting forwardly from each of said clamping elements, brackets secured to the back of said back rest pivotally connected to said second arms to support said back rest for locking movement relative to said frame, and a stop means to limit angular movement of said back rest in one direction and against said frame.

5. In a posture chair having seat-supporting means and a backrest supporting frame extending upwardly therefrom, a back rest, a back rest mounting bracket unit having a rigid cross-bar and spaced arms extending forwardly therefrom, means for supporting said bracket in vertical slidable relationship on said supporting frame and comprising a plurality of spaced elongate guides mounted on said frame, means including elongate clamp elements each partially embracing said guides respectively for locking said mounting bracket unit on said guides in adjusted relationship thereon, a plurality of bracket elements mounted on the back of said back rest and pivotally supporting said back rest on said mounting bracket unit, and resilient stop means on each of last said bracket elements to limit the pivotal movement of said back rest in either direction.

PETER MONDY.

REFERENCES CITED The following references are of recordin the file of this patent:

UNITED STATES PATENTS