US2701745A - Leg positioning mechanism for tables or platforms - Google Patents

Description

Feb. 8, 1955 c. MACKINTSH 2,701,745

LEG POSITIONING MECHANISM FOR TABLES OR PLATFORMS Filed May 16, 1952 4 sheds-sheet 1 I h i K INVENTOR ATTORNEYS Feb. 8, 1955 c. MACKINTOSH 2,701,745

LEG POSITIONING MECHANISM FOR TABLES OR PLATFORMS Filed May 16, 1952 4 Sheets-Sheet 2 I I am 6' z/ 5/ I if z 5 A INVENTOR 7 ,7, [lg

6 1/ BY 91 55. a-a My 9;E-u

ATTORNEYS Feb. 8, 1955 c. MACKINTOSH LEG POSITIONING MECHANISM FOR TABLES 0R PLATFORMS Filed May 16, 1952 4 Sheets-Sheet 3 Feb. 8, 1955 c. MACKINTOSH 2, ,7

LEG POSITIONING MECHANISM FOR TABLES 0R PLATFORMS Filed May 16, 1952 4 Sheets-Sheet 4 ATTORNHS LEG POSITIONING MECHANISM FOR TABLES (JR-PLATFORMS Charles Mackintosh, Los Angeles', Calif.

Application May 16, 1952, Serial N6. 288,166

6 Claims. I i 311 This invention relates to tables and platforms and more particularly to furniture and equipment of-thisv-type which have collapsible or foldableslegs or supporting frames, whereby moving, handling, and' storage of the furniture may be facilitated.

The general Object of the invention is to provide novel and improved tables and platforms of the class described, which are of sturdy and rugged construction, but simple in design and economical of manufacture.

The principal novel feature of the invention is-the provision of an ingenious leg bracing and collapsing means, whereby'the legs or'supporting frames, although pivotally secured to the bottom'ofthe table wellinwardly of the ends, may be readily and quickly released fromoperativeposi'tion: and collapsed and folded against the underside of the table when the latter is to be removed, stacked, or stored.

The principles of he invention'may be embodied in a wide variety of-tables or platforms, but-they probably find 'their most appropriate adaptation in large banquet tables or individual units thereof, or insturdyplat-form eeftions which go to make up temporary-stages or the Otherobjects and features of novelty including novel latching means for the supporting legs or frames in both their extended and retracted positions, will be apparent from the following specification, when read in conne'ction with the accompanying drawings in whichcertain embodiments of the invention are illustrated by way of example.

In the drawings: Figure 1 is a View in vertical section 'of atableembodying the ,principlesof the invention;

Figure 2 is a fragmentary top plan-view *of one end of the table with certain portionsbroken away toshow' underlying parts; e 1

, .F"ure 3 is a -transverse Vertical sectional view of the table taken on .line 3-3 of Figure l;

v Figure 4 ,is a fragmentary sectional view taken on line 4-4 of Figure 2; V,

Figure S is a horizontal sectional detail view taken on line 5-5 of Figure 3.;

Figure 5A is a detail sectional view taken on line SA-SA of Figure 2.; I I Figures 6, 7, and 8 are detail sectional viewstaken on lines 6 v6-, 7v-77 and -8-8,,-respectively, ofl'Figur e 3; Figure 9 is -a view in perspective of a pivot or hinge element for the-leg frames of the table,--su'ch as shown in section in Figure 6;

Figure- -10 is a vertical sectional view taken on line 10"1 0 of Figure 8-;

lfiigure l l is 'a 'vert-icallon'gimdinal' sect-ional view, similar to Figure 1, showing another embodimentof the invention;

Figure 12 "is a vertical transversesectional view of this form of 7 table or platform taken'on line 12- -12 bf Fig"- ure 11-;

T Figure 13 is 'asimilar-view taken-on line 13 -13 of Figure 11; and e V Figure 1'4 is an enlarged fragmentary sectional view taken on line 14-14 of Figure 11. I

Referring now to the embodiment illustrated in Figures 1-10 inclusive of the drawings, the novel folding table which comprises this embodiment of-t'he invention is' indicated generally "by the reference numeral 10. The,

table top 11 maybe of "anysuitable-construction and United States Patent 0 2,701,745 Patented F ch. 8, 1955 ICC 2 in the suggested embodiment comprises atop board 12 having depending side flanges 13 and end flanges 14.

, A central brace bar 15 extends between the side flange elements 13, and at points spaced somewhat from the end bars or flanges 14 other cross members 16 span the width of the table and are preferably snugly fitted against-the underside of the top bo'ard'12 and may be secured thereto or to the side-frame flanges '13.

Disposed beneath each of the cross members 16 are the pivoted leg frames 20. Each of these .leg frames comprises atop bar 21 having spaced downwardly extending bars 22 fixed through or made integrally therewith. Fixed to the lower ends of the vertical bars or rods 22 is the bottom cross bar 24 which is fitted with the feet elements-25 which contact the floor and which will be described indetail presently.

Each end of the upper bar- 21 is pivotally mounted with-respect to the side flanges 13 of the table top 11 and this pivotal connection may be attained by means oft'he pintle brackets 27, the cylindrical projecting portions of which-are adapted to enter recesses in the ends of the upper bars 21. For this purpose, it is convenient to make the-bars 21 in the form of hollow tubular elements or pipes. The pintle brackets 27 are provided with'per-forate'd flanges 28 through which screws 29 or other fastening elements maybe passed in order to secure the brackets tothe side members 13 of the table top. Thepintles .27 maybe made of metal or they may conveniently be formed of plastic material as suggeste in the drawings. v

Theintermed-iate portion 30 of the upper bar 21 of the .leg frame is arched somewhat .as shown inFigur-e .2 of the drawings and when the .leg frame is swung upwardl-y to a substantially horizontal position the arched" or curved portion 30 of-the upper cross-bar enters-the notch or cutaway portion-32 formed in the cross bar 16. The purpose of this arched construction will be explained later.

@In the embodiment illustrated in Figures 3 and 8 of the drawings, the feet 25 comprise blocks of plastic or other suitable material, eachof .the blockshaving a concave'recess in its upper surface adapted to receivethe lower portion of the cylindrical ends oft he bottom bars 24. -Countersunk or recessed portions 33 are formed in the bottoms of the blocks to accommodate the bolts or rivets 35' by means of which the feet are secured to the tubular bar or pipe member 24.

i In Figure 10 of the drawings, a somewhat more elaborate foot-member 25A is shown. In this case the portion of the block'whic'h rests upon the floor is provided with a concave" portion to receive the lower part of the end of the rod 24 and the undersurface is provided with a recess 33 to accommodate the rivet or bolt 35A, but this bolt extends entirely through the pipe or rod 24. The block 25A is provided with a cylindrical portion 36 which enters the hollow end of the pipe or rod 24 and serves to provide asturdier foot piece. The bolt or rivet 35A is also extended throughthe cylindrical portion36 of the foot piece 25A. 7

I A bracing and actuating member is provided for the legframes 20 at each end of the table and these members,

indicated generally by the reference numeral 40, are

somewhat lshaped in configuration having an elongated upper cross bar or tube 41, a downwardly extending bar 42 rigid therewith .and a lower cross piece 44 which has angledend' pieces 45 and is of 'a length :just sufficient to sp'anthespace between the leg frame uprights 22. The hollow or recessed ends of the upper cross piece 41 of each of' the bracing and actuating members receives the pintle projection of the supporting bracket 27A which is constructedexactly the same as the similar pivot bracket 27 for the upper leg bars 21. The common nature of these pivotal connections is indicated clearly in Figure 6 of the drawings.

Thelower cross bars 44 of the bracing and operating frames 40 carry locking devices whereby they may be secured to an intermediate portion of 'the leg uprights 22 when the'legs are in extended operative position. This ldcking means comprises spring-pressed bolts 50 having pointed ends 51 adapted to enter the-holes 52 formed in the-side walls of the tubdlariuprights 22 ofthe leg n mes;

The bolts 50 pass entirely through openings provided in opposite side walls of the extensions 45 of the operating cross bars 44 and again through an opening in the end wall of the housing bracket 55 which is welded or otherwise secured to the inner sides of the extensions 45. A flange 56 is fixed upon an intermediate portion of each of the pins 50 and a coil spring 57 is compressed between the flange 56 and the end wall of the housing bracket 55, and thus serves to urge the bolt 50 into locking position within the opening 52 in the leg members 22. The shank ends of the pins 50 may be provided with eyes 58 and -a wire or cord 59 may be connected between these eyes for manual release of the bolts when it is desired to collapse the legs 20 of the table.

The means by which the frames 40 may be utilized to swing the leg frames 20 inwardly under the table will now be described. This means enables the operator to practically completely collapse the legs inwardly against the underside of the table while standing at the end of the table and without reaching under the table further than necessary to grasp the lower bar 44 of the frame 40. The means by which this is accomplished will be readily understood from an inspection of Figures 2 and 4 of the drawings. Extending between the upper bar 21 of each of the table leg frames 20 and the upper bar 41 of the bracing and actuating members 40, are flexible stra members 60, these straps being preferably of relativelv thin sheet metal and applied in the general form of a figure eight. The respective ends 61 and 62 of the stra s 60 are riveted or bolted to the cross bar 21 of the leg frames as at 63, these points of securement being at the intersection of a right-hand end of a horizontal diameter of the tubular rod 21 as viewed in Figure 4. The bi ht 65 of each of the straps 60 passes around a collar 66 fixed to an intermediate portion of the cross bar 41 of the frame 40 and the strap is riveted or bolted as at 68 at the p int f intersection of the horizontal diameter of the rod 41 with the left-hand wall of the bar as shown in Fi ure 4. The securing of the strap 60 at the points 63 and 68 upon the res ective remote sides of the bars 21 and 41 is accomplished while the parts are in their operative p itions as shown in full in Figure l of the drawin s. The reas n for the provision of the collar 66 will develop presently.

It will be seen that in the position of the legs of the table when it is set for use. the legs themselves make an angle of 90 with the t ble top. and the fr mes 40 stand at an angle of 45 with respect to the table too. Now when one of the bracing and operating frames 40 is unlatched bv pulling on the cord or wire 59 and withdrawing the bolts 50 from the openings 52 in the frame elements 22. it is swung upwardly about the pivots 27A toward arallelism with the table top. During this movement thr ugh the 45 angle, the strap 60 causes the leg frames 20 to rotate in the op site direction toward parallelism with the table top. The sleeve 66 is of twice the diameter of the tubular upper bar 21 of the leg frames and thus for each de ree of swinging movement of the operating frames 40 the leg frames 20 will move two degrees. Thus by the time the actuating frame 40 has moved up to substantial parallelism with the table top, the leg frames will have moved through their travel of substantially 90.

The reason for the provision of the arched portions 30 i on the cross bars 21 will now be understood. The displacement of the arched portion 30 provides room for the central bar 42 of the operating frame 40 when the operating frame is brought up to parallelism with the table top. In order to latch the operating bar in retracted position, the folowing means is suggested. As shown most clearly in Figures 1, 2, and 5A of the drawings there is fixed to the underside of the table top 12, as by means of the screws 70, the upper brackets 75, each of which is provided with an opening 76 within which the pointed end of one of the bolts 50 carried by the cross bar 44 of the operating frame 40 may enter. In order to facilitate the snap-latching of these elements the inner face 77 of the bracket 75 may be sloped as indicated in Figure 5A.

The utility and function of the arrangement which has been described are now fully apparent. In order to collapse the table for removal, transportation, or storage, the operating frames 40 at each end of the table are released by manipulation of the cords or wires 59 connecting the eyes 58 of the rods 50. The frames 40 are lifted and as they move upwardly the leg frames are urged inwardly and upwardly at twice the speed and both of these elements arrive at their ultimate folded position beneath the table top at substantially the same time, the latch pins 50 engaging the openings 76 of the latch plate or keeper 75 to retain the elements in their collapsed positions. It will be apparent that by this means, two attendants may collapse the table by simultaneously actuating the leg frames at both ends; or a single attendant may successively collapse the respective ends of the table, the end bar 14 at the end of the table where the first leg has been folded, resting upon the floor while the leg frame at the opposite end is being manipulated. The legs may be extended and the table set up by a mere reversal of the operation just described.

In Figures 11, 12, 13 and 14 there is illustrated another embodiment of the invention which contemplates the provision of a somewhat heavier and sturdier article which may be used either as a table or as a platform or stage. The same principles of utilization of a bracing frame as a manipulating means for collapsing and fold ing the legs of the platform are involved here as in the case of the earlier described embodiment.

In this case the table or platform is indicated in its entirety by the general reference numeral 100, and comprises the platform proper 101 which includes a top board 102 and a marginal frame comprising the side bars or flanges 103 and the end bar 104.

The platform 101 is supported by two pairs of leg frames, the leg frames of the left-hand pair as viewed in Figure 11 being designated by the reference numerals 105 and 106, and those of the right-hand pair being indicated at 107 and 108. The end leg units 105 and 108 are identical in construction but differ from the intermediate units 106 and 107, these latter units being modified to permit infolding without collision.

As clearly shown in Figure 12 of the drawings, the end leg units 105 and 108 each com rise a horizontal top bar 110 and two depending vertical elements 111 which serve to rigidly connect the top bar 110 with the bottom floor bar 112. Inclined intermediate brace bars 113 are also provided for strengthening the end leg frames.

The upper bar 110 of the end frames 105 and 108 is socketed (if, in fact, the bars are not already formed of tubular material) to receive the pintle proiections which extend from the pivot brackets 114 which are exactly similar to the brackets 27 shown in Figures 6, 7 and 9 in connection with the earlier described embodiment.

The intermediate frames 106 and 107 are both shown in Figure 13 of the drawings, this view being a vertical section taken from the ri ht of the frame 107 and looking toward the leg frame 106 but omitting the showing of any of the end frames and manipulating mechanism. for the sake of clearness of illustration. The nearer intermediate frame 107 is seen to comprise the top bar 115 and three upri ht elements 116, 117 and 118, the u ri hts 116 and 117 being closer together upon one side of the center line of the platform and braced and interconnected by means of the inclined element 119. A floor piece or foot piece 120 is also rigidlv secured to the bottom ends of the upri hts 116 and 117. while the isolated upright 118 rests directly upon the floor or ground surface. The upper element 115 of the frame 107 is pivotally supported by means of brackets 114 similar to those described in connection with the end frames.

The frame 106 as shown in Figure 13 comprises the upper cross bar 122 which is pivotally mounted by means of brackets 114 between the side bars 103 of the platform, and from this upper bar the upri hts 123, 124 and 125 depend, the elements 123 and 124 being braced. to form a single frame unit. by means of the bar 127 and the bottom piece 126. Since the single isolated legs and the double upright frame units of the intermediate leg frames 106 and 107 are disposed upon opposite sides of the center line in non-interfering positions, it will be readily seen how, upon movement toward each other, the two leg frames canintermesh without collislon.

In order to ensure uniform swinging movement of the leg frames 105 and 106, and 107 and 108 of each pair, the bottom ends of the respective frames of each pair are pivotally connected by means of the links 128 and 129, the pivot points being provided in any suitable way and indicated by the reference numerals 130.

The. manually actuatanre. means, provided for collaps ing the leg is, quit similar in principle, to those; described in connection with the. first illustrated embodiment. A bracing and actuatingfram'e- 135 is provided for each pair of'leg frames and, these actuating devices, are illustrated in Figures 11 and 12' of the drawings. Each of these actuating frames l35 comprises. an. upper'cross bar 136 and the depending side bars 137 which are continued at the lower portion of the frame to provide the horizontal lowerbar portion 138. Normally when the legs are. extended as in Figures 11 and 1,2, the actuating frames135' extend outwardly and downwardly from the underside of the latform at an an le of approximately 45 the actuating frame being loopedaround theoutermost legs 105; and 108i and preferably releasably secured thereto by certain latching means which will presently be described. At appropriate intervals along the extent of the upper bar 136 of the actuating frames 135 are secured the collars 140. These collars are in effect pulleys, comparable tothe collars 66 of the earlier described embodiment and are adapted to receive the bight portions of the belts 145' and 146 which are preferably made of strap metal and are fixed as by means of pins 147 to the respective pulley collars. The-ends of the looped belts 146 extend in criss-cross fashion to form a figure eight and are secured as by means of the pins 149 to. the remote side of theupper bar.115 of the adjacent inner leg frame 106.

Similarly, the straps or belts 145 are crossed and extended toward the end leg frames 105 and 108 and are secured at remote points to the top bar 110 of the end leg frame.

The pulley collars 140, just as in the equivalent structure of the first described embodiment are of twice the diameter of the top bars 110, 115 and 122. Thus, when the operating and bracing frames 135 are detached from the end leg frames 105 and 108 and swung upwardly through an angle of 45 to a position substantially parallel with the underside of the table, the inner and outer legs of each pair will be swung upwardly in the opposite direction through angles of 90 and the table may thus be collapsed for removal or stacking.

Although not indicated in the drawings, similar provisions to those described in connection with Figures linclusive may be provided in this embodiment for latching the frames 135 to the underside of the table or platform and for nesting the operating and leg frames beneath the platform top, although a quite adequate folding and collapsing of the legs for most purposes is possible without these provisions, even though the leg frames are not all nested within the actual confines of the platform marginal framing 103, 104.

One suggested latching means for connecting the bracing frame 135 with the end leg frames 105, 108 is shown in Figures 12 and 14 of the drawings. At the curved portion of the frame at the junction of the arms 137 and the transverse portion 138 there is welded or otherwise secured an angular bracket 150. An opening 151 is formed in one arm of the angle bracket 150 adjacent the point where the vertical element 111 of the leg frame would come when the parts are in extended or set-up position. A similar opening 152 is provided in the wall of the tubular frame part 137, 138 and if desired, a tubular boss 153 may be welded or formed adjacent this opening. A further opening 154 is provided in the side wall of the upright 111. A latching bolt 155 is inserted within the openings 152 and 151 and this bolt is provided with a pointed end 156 adapted to be projected into the opening 154 in the leg frame member and a rigid collar 157 is fixed to the bolt just inside of the bracket 150. A coil spring 159 surrounds the bolt and is compressed between the collar 157 and the margins of the opening 152 (in this case the boss 153) and serves to urge the bolt 155 outwardly toward engagement wlth the leg frame. The latching arrangement may be repeated upon the opposite side of the frame as indicated in Figure 12.

In order to withdraw the bolt when it is desired to collapse the table legs the following mechanism is suggested. A cord or cable 160 is secured to the shank ends of both of the bolts 155 at opposite sides of the frame and is trained about the small pulleys 161, 162, 163 and thence through the openings 165 in the wall of the central portion of the cross bar 138 of the actuat ng frame. The central bight or manually operable portion of. the c rd or cable 160, is then passed ar und he x: ternal pulleys 167' and lfibqso as to be readily accessible for manipulation,- Of. course, the guiding; means. for the actuating cable may be modified as, desired and. in fact the, cable may be guided about pins or any smooth rounded portions of structure. within the tubular frame, sharp corners which would fray or wear the cable unduly being avoided. It will bereadily seen that in order to collapse the table logs, the operator will pull the bight portion of the cable 16.0 which lies between the pulleys 1'67 and 168 and this will serve to withdraw thelatch bolts from engagement with. the openings 154 in the uprights 111 and then the frame may be swung upwardly, whereupon the .legs willjbe swung in the opposite direction at twice the rate until, all of the frames are folded up against theunderside of the table or platform,

Various changes andmodifications may be made in the embodiment illustrated anddescribed hereinwithout departing from the scope of the invention as defined by the following claims.

Having thus described the invention, what is claimed as new and desired to be" secured by Letters Patent is;

1- In a folding or' ollapsihle ta l pl tform, t p panel and at least one leg'me'mber pivoted to, the, under; portion of the'top 'panel'tor swinging movement on a horizontal axis'from a substantially verticallpositioninwardly and up y o a- POS ti'on beneath and substantially parallel with the top panel, a dependingbracing and actuating member also pivoted to the under-side of said top panel on an axis spaced from the axis of the pivotal connection of said leg member, belt-and-pulley drive connections between the upper pivoted portions of said leg member and said bracing and actuating member, said bracing and actuating member when in extended position being disposed at an acute angle with respect to said leg member, and latching means for securing said bracing and actuating member to said leg member in order to brace the latter in its operative vertical position, the pulley means on the actuating member being of greater diameter than the pulley means on the leg member, whereby swinging movement of the bracing and actuating member through one angle toward parallelism with said panel will swing the leg member through a greater angle toward parallelism with said panel.

2. In a folding or collapsible table or platform, a top panel and at least one leg member pivoted to the underportion of the top panel for swinging movement on a horizontal axis from a substantially vertical position inwardly and upwardly to a position beneath and substantially parallel with the top panel, a depending bracing and actuating member also pivoted to the under-side of said top panel on an axis spaced from the axis of the pivotal connection of said leg member, belt-and-pulley drive connections between the upper pivoted portions of said leg member and said bracing and actuating member, whereby when said bracing and actuating member is swung upwardly toward parallelism with said panel, the leg member will also be swung upwardly toward parallelism with said panel, said bracing and actuating frame when in extended position being disposed at an angle with respect to said leg member, latching means for securing said bracing and actuating member to said leg member in order to brace the latter in its operative vertical position, and latching means for retaining said bracing and actuating member in retracted upward position beneath said top panel.

3. In a folding or collapsible table or platform, a top panel and at least one leg frame pivoted to the underportion of the top panel for swinging movement on a horizontal axis from a substantially vertical position inwardly and upwardly to a position beneath and substantially parallel with the top panel, said leg frame including a horizontal top rod trunnioned to the top panel to rotate about its own axis, a bracing and actuating member including a horizontal rod trunnioned to the top panel to rotate about its own axis, said last named axis being spaced inwardly from the axis of the leg frame top rod beneath the top panel, said bracing and actuating member normally extending from its trunnion axis to a point of detachable connection with said leg frame in order to brace the leg frame while it is in its downwardly extending operative position, a flexible but inelastic belt surrounding said spaced trunnioned rods, the portion of the actuating member rod about which the belt runs being of greater diameter than the corresponding portion of the leg frame rod, whereby a smaller swinging movement of the bracing and actuating member from its angled bracing position to a substantially horizontal position beneath the top panel will cause the leg frame to move through a greater angle from a substantially vertical' position to a horizontal position beneath the top ane P 4. The folding or collapsible table or platform as set forth in claim 3 in which two leg frames are provided, one inwardly of the other, the bracing and actuating member extending toward detachable connection with one of said leg frames, crossed belt driving connections between the top rod of said actuating member and the top rods of both of said leg frames, and linkage connections between the lower portions of the two leg frames to further brace the structure and ensure parallel movement of said leg frames.

5. In a folding or collapsible table or platform, a top panel and at least one leg member pivoted to the underportion of the top panel for swinging movement on a horizontal axis, a depending actuating member also pivoted to the underside of said top panel on an axis spaced from the axis of the pivotal connection of said leg member, said actuating member extending at an angle with respect to said top panel and having non-supporting relationship therewith, belt and pulley drive connections between the upper pivoted portions of said leg mem- .7 8 ber and said actuating member, the pulley means on the actuating member being of greater diameter than the pulley means on the leg member.

6. In a folding or collapsible table or platform, a top panel and at least one leg member pivoted to the underportion of the top panel for swinging movement on a horizontal axis, a depending actuating member also pivoted to the underside of said top panel on an axis .spaced from the axis of the pivotal connection of said leg member, said actuating member extending at an angle with respect to said top panel and having non-supporting relationship therewith, and a differential connection between the upper pivoted portions of said leg member and said actuating member in order that swinging movement of said actuating member through a lesser angle will swing the leg member through a greater angle.

References Cited in the file of this patent UNITED STATES PATENTS 893,031 Stone July 14, 1908 1,063,642 Birdsall June 3, 1913 1,956,946 Duffy May 1, 1934 2,050,677 Waldschock Aug. 11, 1936 2,086,463 Bram July 6, 1937 2,514,061 Hood July 4, 1950 2,618,523 Boyce Nov. 18, 1952

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