US469378A - Carl schuster - Google Patents

Description

(No Model.)

G. SGHUSTER. SCHOOL DESK. No. 469,378. Patented Peb. 23, 1892.

NVENTOH ATTRNEYS` UNITED STATES PATENT OFFICE.

CARL SCHUSTER, OF BERLIN, GERMANY.

SCHOOL-DESK.

SPECIFICATION forming part of Letters Patent No. 469,378, dated February 23, 1892.

` Application ned May 1891. serai No. 391,713. cto man.)

To @ZZ whom t may corr/cern:

Be it known that I, CARL .SCHUSTEIn cal)- inet-maker, a subject of the German Emperor, residing at 25 Dorothemstrasse, Berlin,in the Kingdom of Prussia, German Empire, have invented a new and useful Improvement in lVriting Tables or Desks for Schools and for other Purposes, of which the following is a specification.

The object of my invention is to provide a writing-table which can easily be adj usted and in such manner that it affords a convenient support for writing and suitable to the height of the person using it.

The invention consists of the usual frame, on top of which is arranged a box-shaped attachment with two bars passing from the front to back of same and two similarbars from one side to the other. To the former bars are secured bearings, in which rotates a rod or shaft carrying two eccentrics or cams in connection with and bearing on the under side of the desk-table by means of elastic bands of steel, leather, or similar material. To the crossbars, or those passing from side to side, are attached the ends of two metallic sliding bars, the other ends of these bars being hinged to the under side of the desk-table. Vhen the desk-table is pulled forward, the elastic bands attached thereto cause the eccentrics to turn, thus causing the desk-table to be raised from a horizontal to an angular or slanting position.

If desired, wedge-shaped pieces can be secured to the under side of the desktable,

against which the eccentrics or cams can operating mechanism. Fig. 2 is a longitudip nal section on line y, Fig. 1. Fig. 3 is a vertical cross-section through the middle of Fig. 2, looking from right to left. Fig. 3 is a similar sectional view showing a certain rack-le ver and spring and the relation of these parts to the general structure of the desk, and Fig. 4 is an enlarged detail view.

. In said drawings, a represents a frame, on the top of which rests or is secured a boxshaped cover or attachment b. Within the frame a and extending from the front to the rear are bars c c, and above these bars 4are other bars d d, extending lengthwise of the frame, as shown in Fig. l. Upon the upper surfaces of the rods c c are firmly secured bearings c e, in which revolves or rotates a shaft or rod f. To the bars d d are secured in any desired manner guides or ways g g, in which reciprocate sliding bars h 7L. Upon the top of theframe a is arranged awriting-table A, adapted to be moved in and out on the top of the table, as will beliereinafter described. To this table A are hinged or pivoted on its under side the forward ends of the sliding bars h 7L, the other ends of said bars being left free, as shown in Figs. l and 8. On the shaft or rod f are mounted or secured two eccentrics or cams 7c 7a, to the outer periphery of which ends of straps or bands s s are attached, the other ends of said straps being secured to the under side of the table A and forward of the shaftorrodf, as shown in Fig. 3. When desired, triangular or wedge-shaped blocks j can be secured to the under side of the table A, as shown in Fig. 3,and are so located that they can be acted on directly `by the eccentrics to aid in assisting the raising of the table to such angular position as may be sought.

To facilitate the reciprocating movement of the bars h 7L and to decrease the friction, I have shown in Figs. 2 and 3 rolls r, upon which the bars h h rest in their movement. To prevent these bars 72, .7L from being drawn too far forward, a groove or recess o can be formed in the rear portion of the bars, adapted and arranged to receive a lug or projection vw on the under side of the table A, as shown in Fig. 4:.

To enable the table A to beiirmly held in any desired position after it has been pulled or drawn forward, a recess m is formed in the upper side of the bar CZ, and in the bottom of this recess is secured by a hinge or pivot one end of a lever n and adapted to rest within the recess when not in use. Vithin this recess is also secured an actuating-sprin g p for controlling the 'lever n.

On the under side ofthe table A and oppo- IOO site the recess m when the table is pushed in is secured a rack or ratchet bar t, arranged to receive and hold the free end of the lever n. This is shown in Fig. 3%

Having thus described my invention, what I claim as new,'and desire to secure by Letters Patent, is-

l. An adjustable writing table or desk combining therein a frame-work a Z), a top A, adapted to slide within said frame-work, sliding bars hh, hinged to the topAand adapted to guide said top in its movement, eccentrics or cams 7c k, elastic bands s s, connecting said cams with said top, said eccentrics being adapted to be raised orlowered bythe sliding movement of said top, and two sets of crossbarsc c and d d for supporting' the shaft of the eccentrics and the guides for sliding bars h h, all said parts being arranged and adapted to operate substantially as described, and for the purpose set forth.

2. An adjustable writing table or desk combining therein a frame-Work d Z9, a top A,

adapted to slide within said frame-Work, sliding bars 7i h, hinged to said top, cross-bars CZ d for guiding said sliding bars, eccentrics or cams 7c 7c, elastic bands s s, connecting said cams with said top, said eccentrics being adapted to be raised or lowered by the sliding movement of top A, a rack i, secured to said top, and a lever` n, pivoted to cross-bar d and controlled by a spring p and adapted to hold the top firmly in any desired position, all said parts being arranged and adapted to operate substantially as described, and for the purpose set forth.

In witness whereof I have hereunto set my hand in presence of two witnesses.

CARL SCHUSTER. Witnesses:

W. H. EDWARDS, W. HAUPT.

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