US2723890A - Latch mechanism for folding lunchroom tables - Google Patents

Description

Nov. 15, 1955 R. R. ERICKSON LATCH MECHANISM FOR FOLDING LUNCHROOM TABLES Filed July 15, 1954 ET" N 0 25 9 T n w 9 a w m 3 E United States Patent LATCH MECHANISM FOR FOLDING LUNCHROOM TABLES This invention relates to a latch mechanism for positively locking a pair of hinged table sections in collapsed position and is particularly adapted for use with my Folding Table and Bench Structure disclosed and claimed in my Patent No. 2,514,319, granted July 4, 1950.

It is an object of my present invention to provide novel and improved means for positively locking the table and bench units of my folding lunchroom table in collapsed position. r

It is a further object to provide a compact and easily operable spring latch mechanism for individually holding the table sections on each side of the center supporting structure in collapsed upstanding relation adjacent said center structure.

More specifically, it is an object to provide a spring latch mechanism shiftably'mounted on the underside of the outermost table section and adapted to cooperate with a fixed latch element mounted on the upstanding support on which said table section is hinged to positively hold said table section in upstanding collapsed position against said upstanding support.

c j 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 top plan view showing one folding table and bench unit in outwardly extending position and the other unit in upwardly collapsed position,

Fig. 2 is a vertical sectional view of the structure shown in Fig. 1;

Fig. 3 is a fragmentary vertical sectional view drawn in an enlarged scale showing the pivoted latch mechanism in latching position;

Fig. 4 is a longitudinal vertical sectional view showing one of the latch mechanisms in locking position by full lines and a fragmentary portion of the other latch shown in locking position by dotted lines; and

Fig. 5 is a fragmentary transverse sectional view taken substantially along the line 5--5 of Fig. 4.

As illustrated in the accompanying drawings, I provide a central upstanding supporting structure, designated as an entirety by the numeral 7, having a pair of upstanding members 8 interconnected by a pair of spaced cross members 9 and 10 and supported on a pair of wheel supported arm structures 11 having the wheels 11a mounted under the end portions thereof.

A pair of upstanding support frame structures 12 and 13 are mounted on each side of the center upstanding supporting structure in outwardly spaced relation therefrom. Each frame structure 12 and 13 is constructed in the form shown with a top cross member and a lower cross member in a similar manner to that described in my patent previously identified herein. Each of the frame structures 12 has an inner table top section 14 hingedly interconnecting the top cross member thereof with the top cross member 9 of the central supporting slot formed therein.

2,723,890 Patented Nov. 15 1955 structure 7 and each of the outer frame structures 13 has an outer table top extension member 15 hingedly interconnecting the top cross member thereof with the top cross member of the frame structure 12 and the lower cross members of the respectively adjacent frame s.truc tures are respectively hingedly interconnected by the bench members 14a and 15a extending along'the sides of the respective table top sections. The frame structures 12 and 13 have supporting legs thereunder similar to the legs described in my patent previously identified herein and said bench and table top units are adapted to be folded upwardly into collapsed position, as shown in Figs. 1 and 2 of the drawing and as described in my said patent.

My present invention consists in providing a novel and improved latch means for positively locking the table and bench units in collapsed upstanding position and consists in a stationary latch member 16 and a shiftable spring latch member designated as an entirety by the numeral 17. The spring latch member 17 has a mounting plate 18 which is fixed to the underside of the central outer free end portion of each table top extension 15, as best shown in Figs. 2, 3 and 4. Thismounting plate supports a pivot pin 19 on which a bell crank 20 on said latch member 17 is pivoted. One of the arms of said bell crank 20 has a notch 21 formed therein and the end portion of said notched arm is beveled as at 22. The other arm of the bell crank 20 has a gripping handle 23 fixed at the outer end thereof, and a spring 24 resiliently holds the latch in locking position. An' outstanding stabilizing guide 18a is fixed as by being integrally formed with mounting plate 18 and received the handle-equipped operating arm of bell crank 20 through an elongated The slot terminates in' slightly spaced relation to the outer free end of the guide 18a and is of suflicient length to permit the necessary oscillation of the bell crank from releasing position to latching position, but engages the outer edge of said operating arm to limit the swinging movement of said arm in the direction urged by the spring 24 and to positively retain the bell crank in a predetermined latching position, the width of the slot is only sufficient to closely receive said operating arm whereby lateral stability is provided for said arm to prevent bending thereof.

The stationary latch member 16 is mounted in fixed relation on the central portion of the lower side of cross member 9 and has a pair of depending locking flanges 16a formed thereon, said flanges being respectively adapted to be received in the notches 21 of latch member 17 which are respectively mounted on the central end portions of the table top extensions 15 as best shown in Figs. 1 and 2.

The following is a description of the operation of my locking mechanism. When the table is to be folded into collapsed position, the sections are shifted into upright relation and the latch member 17 interfits with latch member 16. As the sections approach upright position, the beveled portion 22 engages the flange 16a adjacent thereto and causes oscillation of the bell crank member 20 to permit the flange 16a to be received in the notch 21 thereof. As best shown in Fig. 4, the beveled end portions of the bell crank members 20 are. transversely offset to permit said end portions to be overlapped as illustrated when said flanges are received in the respective notches thereof. The individual latch mechanisms 17 for each of the end table top sections 15 permits each pair of table top sections to be individually held in collapsed position, while the other pair is being lowered into operative position or raised into collapsed position. By positioning the handle member 23 adjacent the outer free end of the table top extension sections 15, the same is readily accessible to facilitate operation thereof and release of each individual latch. The beveled portions 22 respectively engage the flanges 16a to cam the rates arm of the Hell crank 20 into retracted position against the force of spring 24 and permit the depending flanges 16a to ride into and be received by the respective locking notches 21 to theieby form a spring l'atch mechanism which automatically springs into latch position when said sections are folded into ollap's'd position. The stabilizing guide plate 18a prevents lateral ir'npact from bending or displacing the operating arm oifbell crank 20 and provides an extremely strong and durable latch men-1- her.

it will b'e een that I have pmv'ided a relatively simple but highly eflicieiit 'sp'ring latch mechanism for securely and automatically lock fig the hinged table top sections into upwardly foldedcollapsed position. I

It will, of course, be understood that various changes be made in the form, details, arrangement and pro portions of the parts without departing from the scope of this invention which, generally stated, consists in the matter? shown ahd described herein and set forth in the Wh'atI claim is:

l. A latch mechanism of the spring type Comprising a mounting bracket adapted to be securely anchored to a shiftably mounted member, a latch arm with an operatinga'rm fixed -theieto pivotally mounted on said bracket, resilient means urging saidlatch a'r'm into normal position but peimittin'g yieldable retraction thereof, stop means associated with said bracket for engaging one of said arms to positively position the same in normal position, and a fixed latch member cooperatively constructed to interfit with the latch arm when engaged therewith and adapted to be mounted in fixed relation to securely hold said sh'ift'able panel in latched position. I

2. The structure set forth in claim 1, and said stationarylatch member comprising a depending flange and said latch arm having a cooperating notch formed therein to receive said flange with a beveledcamming portion for engagement with said flange as said panel is shifted toward said fixed latch member to cam said latch arm into retracted position against the force of said spring until said flange is received in said notch-.-

3. A spring latch mechanism comprising a mounting bracket constructed to be mounted on the surface of a shiftable panel member, a bell crank member pivotally mounted on said bracket with one arm thereof forming a latch arm and the other arm forming an operating arm, stop means for engaging said bell crank and mounted on said bracket to retain said arms in normal position, yieldable means resiliently urging said bell crank toward said stop but permitting yieldable oscillation thereof away from said stop into i'eti'ac'te'cl position, and 'a fixed latch member constructed to interfit with the latch arm of said bell crank. v

4. A spring latch mechanism comprising a mounting bracket adapted to be mounted on a shiftable member, a latch arm pivotally mounted on said bracket, an operating arm fixed to said latch arm for pivotal oscillation therewith and extending radially outwardly from the pivotal mounting of said latch arm, a slotted guide fixed to said bracket and receiving the outer free end portion of the operating arm in the slot thereof to provide lateral stability therefor, resiliently yieldable spring means normally urging said latch am into latching position, and a fixed latch member constructed to interfit with said latch arm to securely hold and anchor said member on which said bracket is mounted in latched position.

5. The structure set forth in claim '4, and said slotted guide forming an arm-engaging stop for positively limiting the shifting movement of said latch arm with said resiliently yieldable spring means to positively hold the same in predetermined normal position.

References Cited in the file of this patent UNITED STATES PATENTS 2,153,950 Swen May 16, 1939 2,257,522 Baile t Sept. 30, 1941 2,514,319 Erickerson July 4, i950 2,607,647 Howe Aug. 19, 1952 2,650,146 Mugler Aug. 25, 1953

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