US121471A - Improvement in devices for supporting and connecting school-desks - Google Patents

Description

UNITED STATES JAMES S. BANKIN, OF MINNEAPOLIS, MINNESOTA.

IMPROVEMENT IN DEVICES FR SUPPORTING AND IIIJNNEIITINIi SCHOOL-DESKS.

Specification forming part of Letters Patent No. 121,471, dated December 5, 1871.

A in convenient sections or lengths, which fit and are secured together, and in the peculiar manner of joining the parts, for the purpose hereinafter described.

In the drawing, Figure l is a side elevation of three school-desks connected in my improved manner; Fig. 2, a horizontal vertical section of the same; Fig. 3, a perspective view of a sec- 'tion of the beam detached; Fig. 4, a vertical crosssection in plane of line x w, Fig. 1, Fig. 5, a perspective view of several sections provided with dovetails and mortises; Fig. 6, a cross-section of two lengths as connected by dovetail and mortises. n

A A A represent school-desks of ordinary construction, which are connected and supported in an upright position by a central horizontal beam,

B. The latter is made in sections, preferably of the form shown at B' B' B', which are respectively secured to separate desks between the seat a and under side of the desk-shelf a' in any suitable manner. These sections B B intermatch and are connected to each other to form a continuous beam.

I prefer to form and connect the different lengths in the following manner, although any other plan may be adopted that may be found convenient: An upper length, b, of the section B', Fig. 2, is formed with a projecting tongue or tenon, b1, which fits into a corresponding groove,

c1, cut in the upper edge of the length c. These two lengths b c overlap and are secured to each other a portion of their length, leaving ends b2 c2 projecting outward in opposite directions.

In use, one whole section, B', is attached to each desk by securing the upper length b to the under side of the desk-shelf a', and the lower length c to the up per side of the seat a. To connect and support the desks, the projecting ends b2 of the upper lengths b are lapped over and matched with the ends c2 of the lower lengths c, and firmly secured together by means of screws or other convenient methods, the tongue b1 and groove c1 insuring a close and reliable unity of parts. If desired, the different lengths b c need not be secured to each other, as described, until during the operation of setting up the desks, thus economizing space in transportation.

In some cases, to avoid the employment of screws and similar fastenings, and to render the parts more convenient to transport, put together, Sto., I intend to provide the different lengths with vertical and horizontal dovetails and niortises m m n u, Figs. 5 and 6, and, in putting together, the horizontal connections are so arranged as to break joints with and lock the vertical connections. The beam lmay also be attached to the desk and seat in a similar manner, the numerous joints all combining to sustain and lock each other.

Among the many advantages secured by my constructionmay be mentionedits peculiar adaptation for packing and transportation, and the ease and rapidity with which the parts may be put together, forming a perfectly secure and reliable beam, possessing to all intents and purposes the advantages of an integral beam with none of its defects. By the use of short sections, as described, great economy is attained in both material and manufacture. Short lengths of lumber can be more easily procured, and there is less waste than when long lengths are employed. The short lengths can also be more quickly and conveniently handled, and admit of the substitution of machine for hand-work, heretofore employed. Another great advantage secured by my plan is that the danger from warping is reduced to a minimum, the long beams, when formed in one piece, as of old, frequently being rendered useless from this cause. As a result of the numerous advantages secured by my improved construction the cost of the whole is greatly reduced.

In the patent granted to me February 18, 1862, I claim a continuous wooden beam.

What I now claim as my invention, and desire to secure by Letters `Batent, is-

The central beam B, formed of a series of sections by the combination of the upper lengths b and the under lengths c, constructed, substantially as described, for supporting and connecting a series of school-desks, as set forth.

In witness whereof I have hereunto signed my name in the presence of two subscribing witnesses.

Witnesses: JAMES S. RANKIN.

GEO. W. MIATT, J. B. GEEHENHAGEN. (62)

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