US1838856A - Lap table - Google Patents

Description

Dec 29, 1931. o. K. MITCHELL ET AL LAP TABLE Filed Feb. 16. 1927 2 Sheets-Sheet 1 Dec. 29, 1931. o. K. MITCHELL ET A1. 1,838,856

LAP TABLE Filed Feb. 16. 1927 2 Shee'cS-Sheet 2 Patented Dec. 29', 17931 Kras 4ossmiv K; MITCHELL Aim LEONARD o# Miroir-Euro1? OAK PARK; ILLINOIS La? vrieiisL'iiv App1ieation`i1ed` February 16,A '1927. .i Seriall NOJISASB.

Thisinventi'on relatesto tables oisthe kind which, for the sake'of aording amplesupport forthe'ftablelwhen resting upon the lap yor elsewhere, has itsfsupporting legs mount- 5 ed upon a fboard-like base member; and which, for the purpose oi'luinaking the table member adjustable in Vhight'from its said base member as well as angularly adjustable, has its legs in the former Connecting links pivoted to the two members which they connect,

namely, thetable member and the base menibei, and has some `of the'pivotal connections `adjustable `in the plane voffthewmember tov which they are connected.

* One1 object of the present invention isito provide a vertically and angularly adjustable system ofasupportinglinks between a table and its base'which will be of very simple construction, will afford awider variety "'20 of angular adjustment than, has been attainable with constructions heretofore known, will `render tlieftablemore easily adjustable to the various posi-tions whichit can assume, and will combine vertical -adjustability with angular adjustability in a manner to aiord a vide a table whicln'whilehaving itsbase meinberas well as its table Amember in the formelflat boards and while having adj ustment in both the angular presentation ofthe table member andthe height or" Vthe table member above the base membenjwill have its supporting and adjusting links all arranged in pairs, crossed between said members and located in vertical `planes extending ,from `front to rear of the table and so related that the rear portion of the table member can swing about a horizontal axis extending from side to side of the front portion of the table member until it attains,v an' approximately vertical upstanding position, or other desired angle of presentation, and then, with or without material departure from said angle 4of presentatiomcan be movedbodily tov or from the base member in order tofchan'ge itsheight about the base member.

k Still anotherobject is to providea table Arearwardly `extendingE links -bein adapted fof@ltlieakindabove described, in which4 the position "the tablemember may,"if;desired, be used as. a proteetinglscreenaa means 'upon :160 wlrieh tahang aweopy yorfmadeitoserve :any er .purposeworf wliifch 1it=mayf`be suitable.

l 1, i he inventionproceeds Supon the principle oonnectingfthe vertically and fore-and-aft timing*table' member with thebase ineinber-65 ithi ugh n'ieane` of supporting links which tog .Lwiththe members can' all .collapse-into parallel relation, ythe links being. arranged in pairs, all'working `in vertical planes extendingromf front to rear of the table, parallel to @.70 each otherV and tol the -oreeand-aft tilting planeof "theftable member; the lower endsof links'ot Aeach pair being pivoted stationarily,

`to the-fronti and rear margins respectively, of the base member g` and the links beingcrossed 1175 between the-members so that one linkoeach pair'ext'ends fromithe-rear margin of thebase member upwardly and forwardly to the front margin or' the .table member, while the other linkof eaclipair extends from-the front mar- '80 gin ofthe base.memberxupwar-dly and' rearwardly towardithe rear margin of lthe table member; the upwardly Vand Yforwardly eX- tending linksxbeing adapted'-for stationary j pivoting tothe opposite marginsiofthe twoi `memberszgandproviding, by the pivotal conneotions at'their loiward ends, the aforesaid swinging axis uponl which -theftablemember swings vertically A:to .f an; upstanding 'position over the `fr-ont margin oi" "the base, anduproviding, by the. pivotal 4Connections vat their roeren-lathe axis upon which the tablelmember through tliefradius-action of. said links, may swing bodilyupwardg the upwardly and `for stationary pivoting-upon thev ront mar- Igin ot the base memberyandadapted :for

, memberfso asto leavefsaid rear portion unrestrained in its upward swinging movement; the stationary base pivots of the upwardly and rearwardly extending links being adjacent to the forward pivots of the upwardly and forwardly extending links to cause the upwardly and rearwardly extending links to remain in approximate parallelism with the table member in moving tojtheir upstanding position, and the foreandaft movement of their rear ends relatively to the table meinber bein T of suiiicient range, (preferably eX- tending from the rear portion well past the middle of the table member) to permit the table member to move bodily upward a considerable distance, after attaining its upstanding position with or without material change iii its angular relation to the base member; the crossed links of the pairs being, at their crossings, free to move, each Ain the plane of the other, both longitudinally and laterally; and means being provided for fixing the parts at any selected adjustment.

Preferably, the legs of each pair are pivoted together at the places of their crossing, but

" their pivots are received by both legs which they connect, through the medium of slots eX- tending longitudinally of the legs in order that the point of lintersection may change freely and the described movements may take place, and with the substantial advantage of being able to clamp the legs together at their intersections, after a desired adjustment has been attained and thus render the structure more rigid in any position to which it may be adjusted. ln addition to the movements referred to, a table supported from'its base in the manner described is also adapted to be moved relatively to the base vertically with out changing its parallelism with the base, thereby presenting the table atV different heights but in substantially horizontal posi tion and incidentally changing its horizontal oiiset rearwardly in relation to the base; and the structural conditions described also adapt the table, by swinging about the axis defined by its stationary pivotal connections, to assume, any position intermediate of the upstanding or high elevation and horizontal positions referred to and even a position of rearward depression. The two pairs of crossed legs lie in parallel planes extending from front to rear' of the table and spaced apart by approximately the lateral dimension of the device or such proportion thereof as will be suiicient to insure stable support of the table upon the base; the crossed legs are of equal length or so near equal length that they can reach simultaneously from the front and rear margins of the base, respectively, to the rear and front margins of the table member and each pair of legs constitutes a system of mutually bracing links defining the relative positions of the table member and base member, not only by shifting the pivotal connection of one leg or link of each pair upon the Yporting legs with combined sliding and piv- 1 otal connection in one leg of each pair with the table, adapts the table member to assume a position of depression or inclination at a substantial angle to the horizontal in a direction opposite to the upstanding or inclined position first herein referred to.

ln order that the invention may be fully understood, the preferred embodiment there of will be described with reference to the ac companying drawings, in which-- Figure l is an end elevation of the table and base members with their connecting legs in folding or collapsed position.

Figure 2 shows the same parts, from the same viewpoint, after the table member with one leg of each pair has swung to an upstanding angular position about its pivotal connections with the other leg of each pair; said figure also showing in dotted lines the elevation of the table member relatively to the base member while retaining substantial parallelism with the latter.

Figure 3 is a view showing the table member raised from the position of Figure 2 while approximately retaining the relative angle of presentation of its reading surface, in assuming which the upstanding legs have drawn their pivotal connections with the table inwardly along the under side of the table, and the pivotal connections at the crossings of the legs have slid upwardly in the slots of said upstanding legs; and this view also shows in dotted lines a variation of the dotted line position of Figure 2, involving depression of the outer end of the table with replacement of the book supporting ledge; and

Figure l is a view from the left of Figure 2, showing the dotted line position of Figure 2 in full lines.

l represents a table member, and 2 a base member from which said table member supported. As a means for supporting table member 1 from base member 2 with freedom of elevation and angular adjustment, the present invention employs two pairs of legs 3, 4, the legs of each pair being connected by pivots 6, 7, to the base 2 at points thereon adjacent the respective longitudinal margins of said base; and said links 3 and 4: being also pivotally connected at 8 and 9, respectively, to the table member l, but of the said pivotal connections 8 and 9, those indicated at 8 are fixed pivots, while those indicated at pivots 9 inr slots 10 ,of a cleat or flange 11 and 4 of each pair are crossed between the table member 1 andthe base member 2,-and

i at the places of their crossing they are prefeiably Vunited by pivots 12 tor the purpose of firmly, binding the legs together in any relative positions which they mayv assume in i the adjustment of the vtable member 1,' andV s tlierebyreiidering the structure more rigid 'in its various positions. In order that the crossed legs may, While thuspivoted together, assume various relative positions, the pivots d `12 are received in slots 13 and 14 inthe respective legs of the pair', therebyV permitting tie vpivot to move longitudinally of one leg Whenever the other legswings laterally, and at the same time execute such movementlongitndinally of theswinging leg as the radiusV vaction may involve.

Atsuch number of the pivotal connections,

for instance, at moving pivots 9 on the table member and the crossing pivots 12, the pivots are provided with clamping'meaiis, such, for

' instance, as nuts 9a vand 12a', whichv can be readily loosened to permit adjustment and then tightened to hold the tions 'assumed The pairs of crossed connecting and supporting legsrelatedto the' table and base members as described, the device mayassume either a complete folded or collapsed position, such as shown in Figure 1, or any one of the several positionsshown by full and dotted Vlines in Figures 2, 3, and4; In moving from. the position of Figure l1'to the po- Y siti onof Figure 2, table member lfhas its rear or outer margin, together'with the legs totV the respective pairs, 'swung upwardly aboutV the pivotsS vas an axis, in the course of which the crossing pivots 12ivilltra`vel tovvardtlie ends of' the slots .18"and14a'nd be raised slightly by the distance of the inner end of snmed this positiom'nuts 9a and12a may be t `tightened and the position retained, ifiound the slots 14 of the legs 4, assumey an elevationV to involve -convenientgpresentation of the supporting surface ofthe ltable member 1. Or the table member 1, While retaining an angular position approximating that shownV in full lines` in Figure 2, may, bythe sliding of pivots 9 inthe slots 10 of the table mem? ber and the vsliding' of pivots 12 - upvvardlyin pivots 8 and 9, but with sliding movement parts in the posiof pivot 12in; the slot V13, and-therebykbring thevtable into fthe horizontal osition shown` depression of the outer margin of the table memberfl fromthe positionfshovvn in dottedl lines in Figui-e2, ivot l2may befurther "in dotted lines inFigureg2; y contimiiiigv v secured to said table member.A -The legs 3` displaceddownwar ley Vinprslotrl, and ,pivot 9.1112157- move in SloblOe distance t0 .brins the.

table into a position of .depression andpres entation of its supporting :surface Iin the" opposite `direction to thatfinvolved in'Figf representsA avisupporting ledge pre er-` ably ,provided `upon the table member 1,;a n d suitablefin position and dimensions "to, pref d vent reading metterci' any-other object which the table is used'to support', from sliding o tf V the table member when the latter isat a sub` i.

stantialfangle ofelevation.` This' supporting ledge maybe secured in amanner to render itV readily removable, as, forinstanc'e, through meansV of i studs 16 carrying removable nuts 16a. (Figure4)1f It the table member isgivenV an angle of depression suclifas sute'nfge'sted4 by vdotted lines inV Figure 3, the supporting ledge 15 will be changed to the position 15m as 1. A collapsible and reversibleilap-"table,`

comprising boards, a pair of primarycon-V y necting members each having fixed ,pivotal connections with both of the boards, a pair 'of secondary connecting members crossing the primary connecting membersand each havfing pivotal connection'vvith 'one ofthe boards,

means connecting the oppositeendportions of each "of the secondary connectmgdmemfbers with the other board,` for both* pivotal i and tiansversefmovement ofthe last-menv i tioned end .portions relativefto the `said other board', at least onemember, of each` .pair

of connectingmembersfbeing movable along v the other, land I neaiis` for locking said con` j necting" members against pivotal movement K c relative yto the boards. Y the slot 14 from the base'pivot 6. Having as- 2. A jcellapsille jlap tibftmpfsng a iin Y i base board anda table board,fa pair of coni necting members having {fiXed pivotal conneclions atftheir ends with th rear Portion y of thebase vboard and the forward; portion in g members V:pivotally connected atftheir ends with `thej forx `vardjportion of, the base i Vboard" and the rear portion` of *the table board, .the pivotal' connectionsV lvvith the rear portion of tli'etable bo'ard being slidableffor- Wardly andrearwardly v onthe table board, the connecting members Vloi?Qone'pa'ir being disposed across the connectinglmembers of the other pair, and locking means at the crossf ing points of the member slidable longitudinally of the members and adapted to ade vjustably connect the crossed members together and to permit relative adjustment of the boards.

isc

' 3. A collapsibleand `reversible lapftable, comprisingv two boards, tv/o primary connect-l ing `members each-having xedypivotal connections with the boards, two secondary connecting members each Ahaving pivotal con-A nections with the boards, said last mentioned connections with one of the boards being movable relative thereto, said seconda-ry connecting members being disposedacross the w primary connecting members, and locking means at the intersecting points and slidable longitudinally of the members for adj ustably connecting the crossed members together in pairs and to permit relative adjustment of '15 the boards.

4. In a collapsible table a base. board, a table board, a primary support between said boards, comprising a pair .of`legs, each having at its ends lined pivotal connection, re'

ao spectively, with the rear portion of the base yboard and the forward portion of the table board, said legs, by their vertical swinging movement, alilording'bodily vertical adjustment of the table board to different heights 255 above the base board, a secondary support between said boards comprising legs crossing the legs of the 'primary support and having pivotal connections with the respective boards at points offset forwardly Iand rear- 30 wardly of said fixed pivotal connections, said secondary support having, in addition to its pivotal connections with sa'id boards, a yielding movement relatively to the table board which releases the table board tover-v tical swinging movement in assuming angular adjustment, upon its primary support, pivotal connections between the legs at their crossings adapted` to shift theirpositions in response to the height adjustment and angu- 415 lar adjustment of the table board,and means for releasably locking the legsV ofone support against movement'relatively to those of the other support and thereby hold the table to its adjustments.

45 5. A collapsible table/as described in claim el, in which the yielding of the l.secondary support and the shifting of thecroSsing pivots have ranges of movement which Vpermit the table member to swing about itsl pivots on 5% the primary support, from collapsed position to approximately Vertical position and then by the swinging of its primary support, move bodily upward while maintaining its u-gastanding position. i

55 Signed at Oak Park, Illinois thisllth day or" February, 1927. f Y OSSIAN 4K. MITCHELL.

LEONARD 0, MITCHELL.

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