US2381574A - Locking device for folding chairs - Google Patents

Description

Aug. 7, 1945. w. E. CLARIN 2,381574 LOCKING DEVICE FOR FOLDING CHAIRS 7 Filed May 6, 1945 Patented Aug. 7,1945 I Werner Glarin; Ghicago; Ill-J, assijnor ofone 1 half tq AlierLJacobson, Chicagogllla Application-lMayyii,1943; Serial-.l io; 485,219,

"4Olai'ms. (01. 155-442)- V ,This inventiom relates to'ailocking'device for. .ptvotably ;connected1 -foldable andcollapsible members particularlyg as applied. to chairs; commpnlxfknowrnras the Y type; Chairspf thisk-ind; here i0iore:-i n; extensive;use; ihave been. without means for i efiectively lockingsthe seat-in horizontalposition and; the.;1egs;: in their 9X? tended) relationship; Consequently when suchva chainfisi subiectedlto :some-abnormalen extreme din'aryt usesity often collapses stand oxr-ithe seat A with the weightarearwandlyl 0t 3 the @XiSwOii thespiyotal connectioniofi the; seat ,to.

the legs, or when a person has tilted the; chair. baclg-iorritssrear legs; Such strainsoitenmause a ehainot mannaneonates, .notiinfreqncntly tesu s l h n iniurie tia' e sf am to the cha r- The mainlohjectsj of i this linvention therelore, a vIto. provide an; improved form and intercom? nection of. thetparts of a. f01dih chair whereby the.seatfandleeswillibeg-locked automaticallyfand V positively in; their; extended positions I when the c i irgT nfol dedi to provide such an 'improved interlockinggmechanism to 'tne chaiiiparts that the; interlockingrelationship, is easilyand? automatically. releasediwhen an effort, isimade to fold v thechair; andto. providean iimplfovedfchair 00115 Especially hasathis a hazardiwh n aiperson;hasattemptcd,=to

structionwith a mechanism of 'thiskindfwhich is i very simple and economicallto manufacture; and

which is. positive and facile, in operation.

Inthe particular embodiment herein shown:

fFig; l'is a perspectiveviewof the chair in its unflded'fpositiony iv J v gj-2ffs1a fragmentary elevation taken from the inside' ofone of the legs with the-p arts folded ,Or' collapsed? 2 Flgi sis a similar :view'with'thelegs inth'eir' 1 extended relationship; anctwith. the seat" ShOWll I dotted outline just before' the" locking emher-engages its coacting shoulder;

legsmama 1 extended; the'seat likewise bein shown in dotted outline and the locking member is n'iovedintdengageznent with its coacting shoulder? how the pin plates are Fig. 8 is a cross sectional view taken onithe: line 88- of =Fig,4 showing the pivotal connection oftherseattoth iront 1egs;-'a;nd U

Fig.1 9-,-is a perspective View of the-metalcparts which; make: the pivotal. connection 3 showni in.

In the construction [wheres/1th. this improved locking; device. ,h asibeen related,i-the chairseom? prises; a pair. of '1 front:' leg' s l 0 apair 0t l rear legs I hand ,awseat I2-. which-are pivotallx connedted together; and. held inhtheir unfoldedfo seating position by.. a locking inechanism lhereinaiter" de-, scribed v Therfrontlegs in a. ani ate ne ation;

v trated,' ..comprise apa'ir; or. strips; IBIland. M which are of. such a len thiassto extendiagconsitlerable distance above the pivotal .connectionjioi these'at' I land are.- connected together. atltheinupnerend's by, the curved section I51; AQbaCKLreSt; L6; 1" e f cured in the, arcuate portionfbrmedby the sec tion l 5," This backrest also s'erveslas afreiniorcin-g member to insure ,thenecessaryj rigidity m theunperends oithe legstrips l3'fand" M The lower ends of'the. leg strips [3 and) M re on. nested-by areinforcingbar, IT. This further insures the rigidity} of these,stripsgand"provide'sif foot rest. Brackets .l8farerigidly securedtc the respective leg strips 1'3, and; Wat points above'the pivotalconnection ofi'the' seat 12; These brack; ets ext'ndirea ardly to providea pivotaisup' port forth'e rear legs H, i p

v Therea'r legs l'ljcon'iprisea pair cr mes-l s ens zg sim lar; toitlie strips; I33 n I 43* "but consider: ably; shorter: The? upper; ends or these we strips I 9 and 211' are; pivoted? by suitable pins to" the brackets" !8. Transverse 'reinforcing members 21 connect together the lower ends of thei'strips 19 The inner or" opposed iaces cfthe leg strips I 3- ami 20 each' have a slot 22 "extending lengthwise thereof slightly above the middle-portion *of tlie 1egs.- 'rneu-pper" ends of these 'slot's' terminate and 2"0"so' as to provide-the necessarvjirigidity-to Whichconstitute one'of th'e partsofrtheinterwar ingmecliariism hereinafter to be described The seat l2 as shown in this embodiment comprises a panel 24 preferably of veneer construction supported between reinforcing strips 25, and 26. The strip 25 extends across the front and along the sides of the panel 24 whereas the strip '26 extends across the rear of the panel between the ends of the strip 25. The seat is pivotally supported on the front legs ID by' means of pivot pins 21' on which are mounted the angle-shaped reinforcing, spacer members 28 and 29.

The plates 32 are secured to the rear corners of w the seat I2 by means of pins or rivets 33 and 34 as will be noted from Figs. 5 and 6. The plates are further anchored in place by means of strap members 35. secured to the back of the seat strip 26 by means of screws 36 and have their outer ends provided with hooks 31 which extend through recesses 38 formed in the plates 32 adjacent the rear edges thereof. 1 M

The size, shape and pivotal mounting of the blocks or members 30results in thesemembers shifting into and out of engagement withythe shoulders 23 as the legs of the chair are pulled into their final, fully extended position or are first shifted out of such fully extended position. This swinging or locking of the blocks or members 30 is caused by the rocking contact of the upper ends of the members 30 with the upper ends of the slots 22 under the influence of the relative shifting of the front and rear legs near the extreme of their extended relationship. 7

The position of these blocks or members'30 just before they swing into or out of the enlargement for engagement or disengagement with the shoulders 23 is shown in Fig. 3. The position of these blocks or members 30 in theirengagement with the shoulders 23 for locking the seat and legs in their unfolded and extended position is shown in Fig, 4.

It will be apparent from the foregoing description that a chair provided with a locking means of this kind isvery secure against accidental collapse. This could not occur even 'by reason of allof the weight of a person being placed on the seat rearwardly of the pivotal connection With'the front legs III, as would be the case of one standing on the chair seat. Neither could it occur by reason of one tilting back on the rear legs I I.

Even though the chair parts are .thus securely locked in their. extended positions, the. locking mechanism is released by a very slightrearward pressure on the forward edge of the chair seat or a pulling forward on the curved back section witheven a slight pressure against the forward edge of the seat I2. This will cause the blocks or members to shift out of contact with the shoulders 23 and permit their continued downward movement in the slots 22 as the seat and the consequent swinging of the legs are shifted toward their folded positions, as indicated in Fig. 2.

Since certain changes may be made in the foregoing apparatus and different embodiments of the invention may be made without departing These straps have their inner ends,

Fix

from the scope thereof, it is intended that all matter described hereinb'efore or shown in the accompanying drawingshall be interpreted as illustrative and not in a limiting sense.

I claim:

1. A foldable chair comprising pairs of legs hingedly connected together and siftable into and out of collapsed and extended relationship, one pair of said legs having slots extending longitudnally thereof and enlarged at one end to form offset shoulders, at seatpivoted on one of said pair of legs shiftable relative to the other said pair of legs, and means slidable in said slots and pivotally connected to pins mounted on said seat so as to be shiftable transversely of said slots into and out of engagement with said shoulders when said means I engage the adjacent-ends of said slots, thereby releasably locking said seat and legs in their extended positions.

2. A foldable chair comprising pairs of front and rear legs hingedly connected together and shiftable into and out of collapsed and extended relationships, each of said rear legs having formed in one facethereof a longitudinal slot the upper end of which is enlarged to provide an ofi set. shoulder, a seat pivotally attached between said front legs, and members pivotally mounted on said seat and slidably retained in said rear leg slots, said members being shiftable into engagement with said shoulders when said members engage the upper ends of said slots for releasably locking said seat in its horizontal position and said pairs of legs are in their extended relationship.

3. A foldable chair comprising pairs of front and rear legs hingedly connected together and shiftable into and out of collapsed and extended relationships, said rear legs having formed in the opposed face thereof longitudinal slots the upper ends of which are enlarged to provide offset shoulders, a seat pivotally mounted inwardly of its rear edge between said front legs, outwardly disposed pins on the rear corners of said seat, and blocks pivotally mounted on said pins and slidably retained in the adjacent slots, said blocks being shiftable relative to said seat for engagement with said shoulders when said blocks engage the upper ends of said slots for locking said seat in its horizontal position and said pairs of legs are in their extended relationship.

-a pin mounted on, said third member whereby one end of said block is shiftable into and out of engagement with said shoulder when the opposite end of said block engages the adjacent end of said slot for releasably locking said members relative to each other.

WERNER E. CLARIN.

Images