US2293394A - Folding table link latch - Google Patents

Description

8, 1942- u. K. JOHANNSEN 2,293,394

FOLDING TABLE LINK LATCH Filed Oct. 23, 1940 0 /l aH/INNMM INVENTOR.

' ATTORNEY.

Patented Aug. 18 1942 UNlTED STATES iii? a i. ()FFIQE FOLDHNG TABLE LINK LATCH Application October 23, 1-940, Serial No. 3. 225381 1 Claim.

My invention broadly relates to a portable folding table and is more particularly concerned with an improved latch device of the inbuilt type as applied to a collapsible ironing board stand, preferably comprising an all-metal, three legged chassis in which the erected legs are adapted to fold flatwise beneath the bottom face of such board and to be readily latched in erected leg position for use.

A pair of rear legs respectively have one end thereof alignedly pivoted to said bottom face and a centralized inclined front leg may be similarly the numerals If! and II respectively designate a pair of laterally spaced rear legs that may be fabricated from angle iron. These are preferably disposed to constitute a rear leg structure of a type in which the floor contacting ends are automatically spread apart by the use of guide straps l2 when the chassis is unfolded. In colpivoted between outstanding bracket lugs in substantial parallelism with the axis of the rear leg pivots. linked to the front leg for coordinated movement by complementary connecting rods. A unitary bail-shaped brace or the like link may straddle the erected front leg and have its respective terminals pivoted to the rear leg structure. the ironing board is set up for use, my integral bail nose is made to detachabl-y lock in a novel semi-automatic fashion behind a socketed bracket shoulder in order to rigidly retain the erected understructure against collapse. snap tongue may retainedly uphold the cylindrical nose in a certain centered relation to a quadrant profile portion of said shoulder; by merely depressing said retaining tongue, the nose may be conveniently released in an obvious manner.

The object of the present invention is to devise an extremely simple inbuilt nose lock of the indicated character in which the understr-ucture components require comparatively fewessential pivot points and the lock assembly is especially suited for rapid production on an extensive scale at low fabrication and die cost.

The present refinements represent certain structural improvements over my prior Patent No. 2,213,803 issued Sept. 3, 1940. Reference is had to the accompanying one sheet of drawings which is illustrative of a preferred exemplification hereof and in which drawing:

Fig. 1 is an elevational side view of an erected ironing board equipped with my latch devices.

Figs. 2 and 3 respectively show a bottom and a side view of my chassis when fully collapsed.

Fig. 4 represents an enlarged detail of my improved latch as seen along 4-4 of Fig. 5, and Fig. 5 is a cross-sectional view taken along 5-5 of Fig. 4.

Fig. 6 fragmentally depicts an alternative hookup for the Fig. l linkage arrangement.

Referring more specifically to these disclosures,

The medial regions of both rear legs are When A supplemental lapsed position, the rear legs then fall within the board width confines in the Fig. 2 manner. The upper end of each rear leg is pivoted at I3 beneath the bottom board face It. An intermediate pivot lb is located between the respective ends of each rear leg.

A single rigid front leg It has its upper end pivoted at H to said board face by a novel sheet metal bracket l3 extending transversely of the board length. The floor contacting region of my front l g may be provided with a foot pivot is. Mated tie rods such as 25 may interconnect said foot pivot with the respective intermediate pivots 15 for coordinated leg movement between collapsed and erected positions. Each such rod is rigid lengthwise and free from jointed links. As will be understood, all chassis pivotal points are intended to turn freely without binding effects.

My front .leg is preferably stamped up from sheet metal to comprise a cross-sectionally channel shape of which a longitudinally tapered web 2| is provided with integral side flanges such as 22 (see Figs. 4 and 5). The flanges of the divergent upper front leg end are respectively pivoted to a pair of outstanding, laterally spaced ear lugs 23 and 24 that may be pierced from the stamped bracket I8. This bracket may further include an elongated base plate 25 that is firmly anchored crosswise of the board. The front longitudinal plate edge maybe downturned into the curled depending stop shoulder 26 having a quadrant cross-sectional profile of which the lower edge is spaced forwardly beyond the bracket ear lugs to provide for an elongated abutment gap or rod receiving socket 21 extending parallel to the respective rear leg pivots.

Closely contiguous to its pivots H, the relatively wide upper web end region of my front leg may be provided with a rectangular aperture or the like cavity 28 in the Fig. 5 manner to receive the snap tongue 29 therein. This retractible metallic leaf spring may be given a modified L-shaped profile of which one leg extremity may be permanently affixed by the rivets 39 to the front leg web and the other leg extremity crimped to provide for an offset stop lip 3!. The bulging intermediate tongue portion serves as a depressible finger piece. In normal position, said stop lip preferably rests against the bridge bar 33 that defines one transverse edge of the web aperture 28 and thereby positively locates the tongue bulge when the spring 29 is given adequate initial tension for present purposes. It will be observed that such aperture is cut in the wide divergent web face so as not to materially weaken the front leg support.

My bracket ear lugs and the stop shoulder 26 are spacedly formed in integral fashion to receive therebetween the rectilinear nose component 34 of the one-piece bail-shaped brace link 35 made from round bar stock. The link terminals are preferably pivoted coincident with the intermediate rear leg pivots lei as shown; as an alternative, separate equivalent pivots l5 and I5" may be resorted to in the Fig. 6 fashion. When operative, said cylindrical nose is arranged to bear radially upon the quadrant shoulder profile in centralized axial alignment so that any abnormal link thrust shall not tend to disengage these interlocking parts. In erected table position, the dead weight of the nose portion of such bifurcated brace link is upheld against inadvertent drop behind the snap tongue 28 as cross-sectionally indicated in Fig. 5. The length of said nose component is such as to cause adjacent spaced ear lugs to be snugly fitted between the sharply bent rod bifurcations and thereby eliminate pronounced longitudinal end play. When the brace link nose is latch engaged, it becomes positively held against leg collapse, my snap latch being arranged to command egress out of the socket mouth until the finger piece of such latch is deliberately depressed inwardly toward the front leg web.

As regards the intended mode of operation of the described linkage, this may be traced as follows:

To unfold the chassis, the rear board end may be rested upon a floor to allow the rear legs to fall by gravity toward their erected position. The bail nose will then unobstructedly glide lengthwise of either the web 2| or the board face l4 toward the front leg pivot ll. By deft handling, said nose may thereby be freely carried rearwardly into semi-automatic engagement with the latch tongue 29, whereupon said nose may be easily manipulated into its locked position. In fold my table, the latch finger piece is intended to be depressed inwardly into the arrowed direction indicated by dotted outline as 29' in Fig. 5, whereupon the released bail nose 34 may be freely withdrawn from its socket 2! and slid alongside the board face M to allow all the legs to collapse in unison.

In the present instance, there is no need for locking levers, cross head guides or the like. The intended use of my latch tongue 29 will be readily understood by housewives and the like nonmechanically inclined operators. In addition, the bracket die charges and material requirements have been substantially reduced over my prior bail locking devices and the elimination of a manipulative lever leaves the operator free to more comfortably actuate the foldable table legs between their erected and collapsed positions.

Other advantages inherent in my inbuilt leg latch mechanism are believed apparent to those skilled in this art, it being understood that equivalent underlying structural details may be resorted to, all without departing from the spirit and scope of my invention heretofore described and more particularly characterized in the appended claim.

I claim:

A collapsible table or the like adapted to unfold into erected position and which table is provided with a top board, a pair of rear legs alignedly pivoted to the bottom face of said board, a unitary bracket comprising a base plate anchored to said face forwardly of the rear leg pivots and which plate is provided with a pair of substantially parallel ear lugs and with a curled stop shoulder comprising a depending plate ortion having a cross-sectionally concaved profile disposed transversely of and in a bridging forwardly spaced relationship to said ears to constitute a socket whose mouth extends outwardly away from the board face in parallelism with the respective rear leg pivots, a channeled front leg pivoted to said ear lugs and which leg includes a web component having an aperture and an adjacent bridge bar in its pivot end region, mated rod means pivotally connecting the rear legs to the front leg for coordinated movement, an initially tensioned snap tongue carried by the front leg and of which the medial tongue region extends through the web aperture, said tongue terminating in a stop lip that coacts with the bridge bar, and a pair of brace links of which corresponding end regions are respectively pivoted to a diiferent rear leg and the other link end regions are rigidly interconnected by a single cylindrical nose portion enterable into the aforesaid socket mouth in erected leg position, the dead weight of said nose portion when entered into said socket being upheld against drop by said tongue in an axially coincident relation to the curvature center of said profile.

UDO K. J OHANNSEN.

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