US 2764460 A
Description (OCR text may contain errors)
Sept. 25, 1956 G. NELSON FOLDING SECTIONAL. TABLE 5 Sheets-Sheet 1 Flled April 19, 1954 d W .4 7 2 m 4 e c V %w% 6 w 2 y m H v c Qw M p 25, 1956 G. L. NELSON 2,764,460
FOLDING SECTIONAL. TABLE Filed April 19, 1954 3 Sheets-Sheet 2 l 29 2 $1 4 & L34 B51; 20%
Sept. 25, 1956 G. L. NELSON FOLDING SECTIONAL TABLE Filed April 19, 1954 5 Sheets-Sheet 3 XVI/f/VTUR 6455 A. NEZSG/V WWM M Unite States Patent FOLDING SECTIONAL TABLE Glenn L. Nelson, St. Paul, Minn., assignor to Reynold R. Erickson, Forest Lake, Minn.
Application April 19, 1954, Serial No. 423,963
7 Claims. (Cl. 311-92) This invention relates generally to folding tables which may be easily and quickly collapsed for compact storage.
It is an object of my invention, as disclosed herein, to provide a relatively simple folding table which is extremely rigid and stable when in extended position and which is capable of being easily and compactly collapsed, and is particularly constructed to facilitate handling when in collapsed position.
It is another object to provide a folding table provided with a single pair of leg structures which form the sole supporting means for the table sections when the same are in collapsed and extended position.
It is another object to provide a two-section folding table having a single pair of supporting legs respectively underlying said sections with a toggle link truss forming the sole means for supporting the hingedly interconnected inner ends of said sections.
More specifically, it is an object to provide a folding table unit wherein the component members thereof are cooperatively arranged and constructed to form a double parallelogram assembly wherein the center support is common to both parallelograms and interconnects the same to provide a unit which can be compactly and easily folded into collapsed position with the outer supporting legs of the table forming the supporting base for the collapsed unit.
It is still a further object to provide a folding table wherein the linkage thereof is so arranged as to permit said table to be released from completely collapsed position but positively retaining the sections in partially extended position by an over-center locking action to facilitate easy control and handling of the unit during extension and collapsing thereof.
These and other objects and advantages of this invention will more fully appear from the following description made in connection with the accompanying drawings wherein like reference characters refer to the same or similar parts throughout the several views, and in which:
Fig. 1 is a side elevational view showing my folding table in fully extended position by full lines with portions thereof broken away, and also showing by dotted lines said table in partially collapsed position;
Fig. 2 is a side elevational view of my table shown in fully collapsed position;
Fig. 3 is an end elevational view of my table with the table top sections removed, but shown in outline by dotted lines;
' Fig. 4 is a side elevational view of my table with'the sections thereof retained in partially extended position by the over-center action of the supporting base structure and interconnecting members;
Fig. 5 is an enlarged fragmentary bottom plan view taken substantially in the plane indicated on the line 55 of Fig. 1;
Fig. 6 is an enlarged fragmentary horizontal sectional view taken substantially along the line 6-6 of Fig. 2, showing the arrangement of the center post structure.
2,764,4fi9 Patented Sept. 25, 1956 Fig. 7 is a similar view taken substantially along the line 77 of Fig. 2;
Fig. 8 is a similar view taken substantially along the line 8-8 of Fig. 2;
Fig. 9 is an enlarged fragmentary side elevational view showing the center post latch mechanism in detail;
Fig. 10 is a side elevational view of an alternative form of my folding table showing the same in extended position by full lines and in partially collapsed position by dotted lines;
Fig. 11 is a view of the form of my invention illustrated in Fig. 10 in fully collapsed position;
Fig. 12 is an end elevational view thereof with the top table sections removed but shown in outline by dotted lines;
Fig. 13 is a side elevational view thereof showing the sections retained in partially extended position by the over-center action of the supporting base structure and interconnecting members; and
Fig. 14 is a fragmentary horizontal sectional view of the center post structure taken substantially along the line 1414 of Fig. 10.
As illustrated in the accompanying drawing, I provide a pair of table top sections respectively designated by the numerals and 21 and adapted to be horizontally disposed in end to end relation when in operative position, as shown in full lines in Fig. 1 which shows form A of my invention. The two sections 20 and 21 are pivotally interconnected at their inner ends for swinging movement on a transversely disposed horizontal axis positioned below said sections. A pair of hinge brackets 22 having pivot pins 22a are respectively fixed in transversely spaced relation to the inner portions of said sections 20 and 21 adjacent the longitudinal marginal edge portions thereof, as best shown in Fig. 3.
A pair of supporting leg structure assemblies, respectively designated by the numerals 23 and 24, are hingedly connected to the respective table top sections in longitudinally outwardly spaced relation from the inner hingedly interconnected ends of said sections 20 and 21 as by the hinges 25. The leg assemblies 23 and 24 are, in the form shown, made up of a pair of generally upright elements 23a and 24a laterally offset at the upper ends thereof to form attachment arms 23b and 24b to which hinges 25- are securely fixed. The lower ends of said leg assembliesare horizontally offset longitudinally outwardly away from the center of the table, as best shown in Fig. 1, toform a pair of base arms 23c and 240 to which cross arms 23d and 24d are fixed and to which caster units 26 are attached.
In the form shown, a hollow mounting and guide post 27 is connected at the center of the entire table assembly. The upper portion thereof is securely anchored to said two table top sections by a pair of hinge brackets 28 which are fixed to the table top sections 20 and 21 as by the screws 22b. As best shown in Fig. 6, the hinge brackets 28 are interconnected by hinge pins 28a which are securely anchored at their inner ends to said post 27. A reinforcing collar 29 surrounds said post at the point of interconnection of said hinge brackets 28 and said hinge pins 28a extend outwardly therethrough and, as has been previously stated, pivotally interconnect said two brackets 28 While permitting said post 27 to remain in substantially vertical position at all times.
A pair of stretcher bar members, respectively designated by the numerals 30 and 31, have their outer end portions respectively hinged to a pair of cross bar members respectively interconnecting intermediate portions of the upright leg elements 23a and 24a of the leg assemblies 23 and 24, and said cross bar members are respectively designated by the numerals 23e and Me, as best shown J! nner ends of said stretcher bar 'votally connected to said center bracket elements 32 which d the lower portion of a? which has a second reincollar 33 surro nding the same and through which d. As best illustrated in Fi' l, in the center portions of the bracket in and 32 are shown broken away, the hinge brackets 28 and 32 have the top horizontally disposed web thereof recessed to receive the post 27 therethrough when said table is in extended position.
An upstanding toggle guide member 34- is slidably mounted in telescoping relation within hollow guide post 27 and has a pair of toggle links 35 respectively pivoted at their lower ends to said upstanding toggle guide member d as by b ing pivotally connected to a cross bracket 36 which is fixed to the lower end of said guide member. Said toggle links 35 extend upwardly through elongated slots 32b formed in the top web of the hinge brackets 32, as best shown in the fragmentary bottom plan view, Fig. 5, which is taken along the plane indicated at 5 of Fig. l. The upper ends of said toggle links 35 are pivotally connected to the outer portions of the two center hinge brackets 21%, as best shown in Fig. 1, and a bell crank type latch member 37 is pivotally mounted at the lower portion of depending guide post 27 and cooperates with a latch bar 37a fixed to the cross bracket 36 to positively lock the table in extended position, as best shown in the enlarged detail view, Fig. 9.
The following is a description of the operation of my new table. When the table is in extended position, as shown by full lines in Fig. l, the length of the guide post 27 is such that a positive stop is provided to limit the upward shifting movement of the toggle guide member 34. In the form shown, this stop is provided at the bottom of said post 27 and consists in the engagement of cross bracket 36, which is fixed to the guide member 34, with the bottom end of said post 27. This positively limits the upward shifting movement of the lower ends of said link 35 which resist downwardly directed pressure on the table top sections by pulling upwardly on said center table assembly just described. This downwardly di ected pressure applied to the table top sections and 21 tends to cause said sections to shift downwardly and swing inwardly about the pivot pins 2811 This downward swinging would, of course, require the upward shifting of the lower ends of the toggle links 35, and this shifting is, in the form shown, provided by engagement of the cross member 36 with the lower end of post 27 to thus form a truss assembly which produces an extremely stable table unit which provides a substantially clear span between the floor-engaging leg assemblies 23 and 24 and which is obviously unaffected by irregularities in the floor surface between said legs.
When the table is desired to be collapsed, the pivoted latch element 37 is pressed inwardly at the top thereof and the center portion of the table is lifted upwardly as indicated by the dotted lines in Fig. 1. This upward shifting obviously draws the outer ends of the table top sections together about the hinge pins 22a and 28a which are axially aligned, and this causes the lower ends of the toggle links 35 to be projected downwardly to push the guide member 34 downwardly and extend the same from the hollow supporting post 27. When the axes of the hinges 25 reach the respective center line planes drawn through the axis of the hinge pins 22a and 28a and the respective axes of the caster Wheels, as best shown by the upwardly convergent dash lines in Fig. 4, the structure will be in a relatively stable balanced condition with relatively little tendency for the table top sections to move in either direction. inwardly directed pressure on said table top sections will shift the same inwardly into the over-center position shown in Fig. 4 wherein the outer surfaces of the leg assemblies 23 and 2d respectively en gage the inner or lower surfaces of the table top sections 21 and 22. In the form shown rubber bumpers 26a and 21:: are provided to cushion the impact between said members and to provide a fixed pad therebetween. it will be seen from Fig. 4 that the shifting of the sections 29 and 21 inwardly from the balanced position indicated by said dashed lines will cause the upper ends of the leg structures 25 and 24 to converge slightly and slope inwardly in substantially parallel relation to the table top sections and the upstanding portions of the leg assemblies 23 and 24 will remain in parallel relation to said table top sections during the final collapsing of the table unit into the position shown in Fig. 2. Suitable means for retaining the table in fully collapsed position are provided such as the spring latch member 38 pivotally mounted on pivot pin 39 and extending inwardly through a slot in a guide plate 443. The latch lever has a bar receiving notch to receive a latch bar 4-1 fixed in inwardly extending relation to the lower portion of the other leg assembly, a best shown in Figs. 2 and 4. When the latch lever 38 is depressed to release latch bar 41, the table sections 26 and 21 will spread apart at the bottom into the position shown in Pig. 4, but the over center action of the pivots will prevent further unfolding of the table top sections without additional spreading force being applied thereto to move said sections outwardly beyond the dashed balance line shown in Fig. 4. After the hinge pins of hinges 25 pass outwardly beyond said dashed line, the tendency will be for the table to extend further into fully extended operative position and the operator merely holds the inner end portions of the two sections to gradually lower the center portion of the table into the full line position shown in Fig. 1 wherein the two leg assemblies 23 and 24 again form the sole means for supporting a table. it should be noted that the longitudinally extending arms 23: and 240 pro vide an extremely stable base structure and each pair of arms combines with the respective cross bars 23d and 24d to form a base unit and said two base units carry suitable floor-engaging supporting elements such as the casters 26 for permitting the table to be rolled from one location to another when the same is in folded position. These longitudinally extending base arms 23c and 24c are disposed below the lower outer edges of the table sections 29 and 21 to permit said sections and the upright portions of the leg assemblie 23 and 24- to be compactly collapsed into closely spaced parallel relation, as is best shown in Fig. 2, while still providing a relatively wide stable base structure which is formed from the two base units.
An alternative form of my invention is illustrated in Figs. 10 through 14, inclusive, and is designated by the letter B. in this form of my invention, a pair of table top sections 20' and 21 are provided which are substantially similar to the sections 29 and 21. The inner ends of said table top section 29' and 21' are pivotally interconnected for swinging movement on a pair of spaced horizontally disposed axes 42 and 43, and a hollow center post member 44 is interposed between said axes and, as best shown in Fig. 11, is pivotally connected at its upper end to the underlying and supporting frame for said axes to permit said post 44 to be maintained substantially vertically. A center guiding member 45 is telescopically received within hollow post member 44, and a pair of toggle links 46 are pivotally interconnected at the lower end of said guide member 45 with the upper ends of said toggle links being pivotally interconnected to the bottom of the respective table top sections 20' and 21. A springpressed pin 47 extends transversely through the post member 44, as best shown in Fig. 14 and, when telescopically mounted member 45 is in fully upwardly projected position at the time the table is fully extended, the pin 47 will be brought into registration with a cooperating aperture in the upper portion thereof to securely lock the table in extended position. A handle 47a is provided for controllably retracting said pin and the inner end thereof may be beveled to, in effect, form a spring latch when the table is being extended. A pair of depending legs 48 are pivotally connected at their upper ends to intermediate portion of the table top sections 20' and 21 and have high friction padded lower ends such as the rubber tips 4801 on the bottom thereof to engage the floor surface when said table is fuliy extended and prevent shifting of the table on the floor surface when the same is in use. Two pairs of caster wheels 49 are connected with the lower portions of the legs 48, with each pair thereof longitudinally spaced outwardly from its respective leg as best shown in Fig. 10. In the form shown, each leg structure 48 is made up of a pair of transversely spaced-apart substantially parallel depending leg elements 4811, with each of said elements being bent laterally outwardly at the bottom to form rigid mounting and stabilizing arms 480, with said tips 48a being mounted on downwardly bent, extreme end portions on the lower end to each leg element 48b.
Each pair of caster wheels is interconnected by a transversely disposed cros member 50 which is pivotally connected with the lower end portions of the adjacent leg structure 48 as by a pair of parallelogram links 51, as best shown in Figs. and 11. A pair of stretcher bars 52 respectively interconnect intermediate portions of said leg structure 48 with the center post member 44 and are pivoted at their inner ends to said post member and in slightly spaced relation to their outer ends to substantially medial portions of said leg structures as at $3. The axes of said pivots 53 are disposed respectively adjacent the outer planes of said leg structures 48 and actuating lever arms 52a are formed on the outwardly extended end portions of said stretcher bars 52. The outer extremities of said stretcher bar extensions 52a are respectively pivoted to a pair of actuating links 54, the lower ends of which are pivotally connected to an intermediate portion of said cross bar 50 as at 54a. Obviously, the outer ends of parallel mounting links 51 will be projected downwardly as the center portion of the table is raised toward collapsed position to engage said caster wheels 49 with the floor surface, and said caster wheels will be raised from the floor surface when the table is in fully extended position with the outer ends of the stretcher bar extension levers 52a disposed in raised position, as best shown by the full lines of Fig. 10. In the form shown, the actuating links 54 have rigid right-angle bends formed therein but the apex of the bend is entirely free and is not connected to any of the operating mechanism. In other words, the said actuating links 54 are connected only at their upper ends and at their lower ends to the respective pivots.
A lock is provided for holding the table sections in collapsed raised position which is generally similar to the spring latch mechanism provided in form A of my invention having a resiliently mounted latch lever 38 pvotally mounted on the lower portion of one of the leg structures 48 and a fixed latch 41 fixed to the other leg structure to interfit with said pivoted latch as shown in Fig. 11.
The operation of form B of my invention .is very similar to that described for form A since the center toggle link trus structure is substantially identical with the truss structure previously described and securely supports the inner ends of table top sections 29' and 21. The projection and retraction of caster wheels 49 has been described and .it will be seen that this permits automatic anchoring of the table in fully extended position to prevent movement of the unit when in use. Form B of my invention also has the over-center retaining action described for form A of my invention when the table in Fig. 13.
It will be seen that I have provided a relatively simple, yet highly efiicient table structure which can be compactly collapsed and easily moved from one location to another when in collapsed position with the outer supporting leg structures forming the wheeled base for the collapsed unit. In form B of my invention, the caster wheels 49 are automatically elevated when the table is in fully extended position to permit the rubber friction tips 48a to securely hold the table against shifting movement in the desired position when .in use.
It will, of course, be understood that various changes may be made in the form, details, arrangement, and proportions of the parts without departing from the scope of this invention which, generally stated, consists in the matter shown and described herein and set forth in the appended claims.
What is claimed is:
1. A folding table comprising a pair of hingedly interconnected table top section disposed in end to end relation and lying in a horizontal plane when in operative extended position but being collapsible into substantially vertical position with their hingedly interconnected inner ends elevated, a depending center support hingedly mounted at the inner ends of said sections, a pair of depending leg assemblies respectively hinged to .intermediate portions of said sections and spaced a substantial distance inwardly from the outer ends of said sections, rigid interconnecting elements hingedly interconnecting said center support and said leg assemblies and disposed in substantially parallel spaced relation below said table top sections to form a pair of hingedly interconnected parallelograms arranged in end to end relation, and means for maintaining said leg assemblies and said center support in substantially vertical position during the swinging of said table sections, releasable locking means positively locking said table in fully collapsed position, said leg assemblies having longitudinally disposed outwardly offset lower portions provided with longitudinally spaced-apart floor-engaging elements to form the sole means for supporting said table when in collapsed position, the hinge connections between the table top sections and the respective leg assemblies forming a pair of knee pivots respectively disposed between the section interconnecting hinge means and the floor-engaging elements whereby an overcenter retaining action is provided to positively hold the table sections in partially collapsed or partially open position which prevents sudden dropping of the table into operative position after initial release of said retaining lock.
2. A folding table comprising a pair of hingedly interconnected table top sections disposed in end to end relation and lying in a horizontal plane when in operative extended position, a pair of supporting legs hingedly connected to said sections in outwardly spaced relation to the inner ends thereof forming the sole supports for said table when the same is in operative extended position as well a in collapsed position, a depending support shorter than said legs mounted in hinged relation at the inner ends of said sections and forming a supporting strut for a toggle truss assembly, a pair of toggle links respectively pivoted at their ends to said table top sections and to said center support with means for permitting rectilinear movement of one end of each of said links, positive stop means for limiting the rectilinear shifting of said links when said table sections are disposed in horizontal operative position whereby the inner ends of said table section are supported in elevated relation without requiring a center floor-engaging support, and a pair of interconnection members respectively disposed in substantially parallel spaced relation below said table top sections and hingedly interconnecting said supporting legs with said center strut to provide a pair of hingedly interconnected parallelograms arranged in end to end relation.
3. The structureset forth in claim 2 and said center supporting strut being hollow and provided with a telescopically received toggle guiding member, said toggle links being pivotally connected to said telescopically received toggle guiding member at their lower ends and being pivotally connected at their upper ends to said table top sections in outwardly spaced relation from the inner ends thereof, and stop means between said guiding member and said hollow strut for positively limiting the upward shifting movement of said guiding member into saidrstrut.
4'. The structure set forth in claim 2 and latch means for positively locking the table sections in extended operative position.
5. A folding table comprising table top sections arranged to swing from horizontal operative position into substantially vertical collapsed position with the surfaces thereof disposed in substantially adjacent bottom to bottom relation, a depending center support underlying the central portion of said table when in horizontal operative position depending leg assemblies respectively hinged to intermediate portions of said sections and provided with longitudinally disposed outwardly offset lower portions with floor engaging roller elements thereunder, the upper ends of said leg assemblies being spaced inwardly from the respective outer ends thereof a distance less than the length of the upstanding portions of said leg assemblies, stiff interconnecting elements hingedly interconnecting, said center support and said leg assemblies, means for maintaining said leg assemblies and said center sup port in substantially vertical position during the shifting of said table sections, said roller elements shifting said sections from one position to another and providing the sole means of supporting said table when in collapsed position with said longitudinally offset portions underlying the respective end portions of said table top sections, said leg assemblies and said center support being so constructed and positioned with respect to each other and-with respect to said table top sections to permit said leg assemblies and center support to lie in substantially contiguous planes when collapsed to produce an extremely compact easily stored unit.
6. A folding table comprising a pair of table top sections arranged for relative swinging movement from one position to another and disposed in longitudinal alignment when in horizontal operative position and in upstanding substantially bottom to bottom relation when in collapsed position, a pair of underlying leg assemblies respectively hinged at the outer end portions of said sections and provided with longitudinally outwardly oifset lower portions to provide an underlying stable base structure forming the sole means for supporting said sections when the same are disposed in collapsed position with the upstanding portions of said leg assemblies lying in substantially contiguous planes, the upper ends of said leg assemblies being respectively spaced inwardly from the outer endsof said sections a distance less than the upstanding leugth of said leg assemblies to permit the outwardly ofilset lower portions of said leg assemblies to extend outwardly beyond the collapsed upright table sections to permit said base structure to be wider than the collapsed sections, roller elements underlying the outer end portions of said base structure to facilitate collapsing said sections and moving the same when in collapsed position, a center support member depending below the inner of said sections and hingedly mounted relative thereto, means maintaining said leg assemblies and said center support in substantially vertical position at all times, and releasable means for holding said sections in collapsed position.
7. A folding table comprising a pair of elongate table top sections having their inner ends hingedly interconnected for swinging movement between a horizontal position With the sections disposed in longitudinal alignment and a collapsed position in which the sections are in substantially vertical, opposed bottom-to-bottom relation, a pair of underlying leg assemblies respectively hinged to the undersurface of said sections intermediate the opposite ends thereof and provided with outwardly and oppositely offset generally horizontal lower portions, means for maintaining said leg assemblies in substantially vertical position at all times, a center support underlying the inner ends of said two sections for supporting the inner end portions of said table sections, releasable means for holding said sections and leg assemblies in collapsed position, the upstanding portions of said leg assemblies being hingedly connected to the respective table top sections at points spaced inwardly from the outer free ends of said sections a distance less than the upstanding length of the upstanding portions of said leg assemblies to permit the outer free ends of the table top sections to clear the lower portions of the leg assemblies when the sections are disposed in collapsed position with the upstanding portions of the leg assemblies being drawn together on opposite sides of said center support with the undersurfaces of the table top sections lying immediately adjacent to and outwardly of the upstanding portions of the leg assemblies, providing a vertically elongate but compact assembly when in collapsed position.
References Cited in the file of this patent UNITED STATES PATENTS 1,062,996 Sornberger, May 27, 1913 1,424,610 Zielonko Aug. 1, 1922 1,808,305 Howe June 2, 1931 1,930,176 Metzler Oct. 10, 1933 2,203,394 Schieber June 4, 1940 2,257,522 Bailey Sept. 30, 1941 2,544,228 Hoppe Mar. 6, 1951 2,650,146 Mugler Aug. 25, 1953