US636816A - School furniture. - Google Patents

Description

Patented Nov. I4, I899.

c. H. LAWTON. SCHOOL FURNITURE.

(Application filed Jan. 19, 1899.)

(No Model.)

NITED STATES PATENT OFFI E.

CHARLES H. LAVVTON, F WABASH, INDIANA.

SCHOOL FURNITURE.

SPECIFICATION forming part of Letters Patent No. 636,816, dated November 14, 1899. Application filed January 19, 1899. Serial No. 702,690. (No model.)

T0 all whom, it may concern.-

Be it known that 1, CHARLES H. LAWTON, a resident of Wabash, in the county of Wabash and State of Indiana, have invented certain new and useful Improvements in School Furniture; and I do hereby declare the following to be a full, clear, and exact description of the invention,such as will enable others skilled in the art to which it pertains to make and use the same.

The invention relates to school furniture and the like, and has for its object to provide a firm connection between a back, seat, or like part and its supporting-frame.

The invention consists in the construction hereinafter described and pointed out.

In the accompanying drawings, Figure 1 is a side elevation, partly in section, of a seat and its support. Fig. 2 is a transverse section on line 2 2 of Fig. 3. Fig. 3 is an elee vation of a hinge, one of the leaves being removed and its securing-screw and the hingepivot sectioned. Fig. 4 is a section on line 4 4 of Fig. 1. Fig. 5 is a partial bottom plan of the seat, and Fig. 6 is a plan of the seatsupport.

Numeral 1 indicates a part of a wooden structure, such as the back of a school-desk or a seat therefor.

2 denotes a part of the metal supportingframe, being in the instance illustrated a hinged seat-supporting arm.

3 indicates the central leaf of a hinge made integral with the arm.

4 denotes a leaf and the frame-standard, and 5 a cap or loose leaf, both cooperating with the central one. The leaf 4 has a concavity to receive a boss 6, formed about the central opening of leaf 3. This boss fitting the concavity acts as an axis and relieves the screw 7 of a part of its duty.

Rubber or leather pieces 8 and 9 are interposed between shoulders 10 and 11, respectively, to obviate jar and noise.

The seat has in its under side a groove 12, having a length nearly equal to the width of the seat and provided at intervals in its bottom with a series of comparatively long in-' elines 13 and oppositely-situated short inclines 14, alternately arranged, as best shown inFig. 1. By arranging the short inclines to meet the long inclines, as shown, the crests 15 are formed below the surface of the mate rial and aid materiallyin securing the parts, as the lugs may be placed directly in the groove, thus initially holding them in proper alinement throughout the length of the seat. The crest or apex 15, where the long and short inclines of each pair meet, is slightly below the general surface of the seat and adjacent the widest part of a series of openings 16, which together constitute the outer or more superficial part of the before mentioned groove 12. Superficially the grooves are con tracted intermediate the points 15 and adjacent their deepest parts 16,where the inclines disappear, the narrowest parts of said groove being nearer the short than the long inclines.

The side walls of the groove 12 are undercut at 17 on each side, so that the faces 17 overhang its deepest parts. A seat, back, or other suitable part being provided with a continuous groove 12, such as shown and described, is joined to a support or arm like that indicated at 19 in Figs. 1, 2, and 6, by means of dovetailed lugs 20, formed at suitable intervals on said arms. These are made nearly rectangular on their outer face and are undercut on each side at 22 and also at 23 on one end. The outer faces are inclined to the adjacent surface of the arm, as shown. 24 denotes a rib adapted to bear on the crest 15 when the arm and seat are joined, and it occupies a space below the surface of the part 1 about equal to or a trifle greater than the depth of said crest below the same surface, so that it acts to draw the faces 22 against the undercut faces 17 when the arm and seat are forced together.

It will be understood that the surface 25 of the arm has approximately the same contour as the seat and is adapted to fit it when the parts are joined. To effect this junction, the edge of each lug is entered at the widest part of the groove near a crest 15 and the arm is forced forward to press the lugs over the crests and down the long inclines. By this operation the edges of the lugs are made to engage the short inclines and to wedge the lugs against the overhanging side walls of the groove. These crests are below the proximate surface of the seat (or other part) 1, as shown in Fig. 1, and being situated in the widest or lug-entering region of the groove their depression has the effect to shorten the inclines 13 at their upper end and to permit the overhanging faces 17 to extend farther backwardly. This shortening of the inclines 13 allows the lugs to be placed nearer each other, which facilitates a close fit of contiguous curved parts-that is, a superficial fit of the arni and seat or back, as the case may be. It also provides for the easier entrance of the lugs, which are initially placed with their toes upon the crests and below the surface of the seat, whereby they are held in proper alinement and whereby they are guided when pushed home under the said faces 17. When the lugs are forced into the grooves, as stated, the narrow rib 24 will, if necessary, be pressed into the wood at the crest 15 and aid in holding the lugs engaged under the overhanging side walls of the groove. Obviously if the so-called crests were made flush with the seat-surface the difficulty of securing a close superficial fitof the arm and seat would be enhanced. The contact of the rib and crest is narrow and below the surface of the seat and will not materially interfere with closely fitting together the surfaces of the arm and seat. The pressure of the lugs is mainly lengthwise the grain of the wood. The crowding of the wood between the undercut portions of the lugs and the surface 25 of the arm compresses but does not split it.

If green wood be employed, the arm and seat may be easily made to fit by forcing the lugs into the groove, as such wood yields with comparative readiness. lVhen subsequently seasoned, the wood contracts and the union is made more firm.

I am aware that a series of slats have been provided with a groove without inclines and having portions made comparatively wide to receive lugs fixed to a standard and having intermediate portions provided with undercut walls to engage the lugs, and such groove and lugs, broadly, are not of my invention.

Having described my invention, I claim- 1. A seat or the like provided with a continuous groove having a series of alternate long and short inclines in its bottom and having its sides undercut, the proximate inclines being of opposite inclination and arranged to meet on a plane below the surface of the material, in combination with a support having a series of undercut lugs adapted to fit between the undercut sides of the groove and initially held in alinement with the groove by being placed on the meeting-points of thei11- clines, the shorter inclines serving as an additional lock for the lugs.

2. A seat or the like provided with a continuous groove having a series of alternating inclines in its bottom and having its sides undercut, the junction of the inclines forming a crest, in combination with a support having a series of undercut lugs fitted between the undercut sides of the groove, and ribs intermediate the lugs adapted to be pressed into the crests when the parts are locked together.

3. A seat or the like provided with a continuous groove having series of alternating inclines in its bottom and having its sides undercut, the junction of the inclines forming a crest, in combination with a support having a series of undercut lugs fitted between the undercut sides of the groove, said inclines being entirely below the proximate seat-surface and the groove having wide portions near the top of the depressed inclines and narrow portions over the bottoms of said inclines, said support having a longitudinal rib between the lugs, adapted to be pressed into the crests when locked.

In testimony whereof I have signed this specification in the presence of two subscribing witnesses.

CHARLES H. LAWTON.

Witnesses:

SARAH HIPSKIND, OLIVER H. BOGUE.

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