US229619A - John d - Google Patents

Description

1! Mill. H J. D. LITLE V Dividing Compass.

No. 229,619. Patented July 6, i880.

WW nl efiliur @Z w a I set the set-screw. This set-screw, moreover,

UNITED STATES PATENT OFFICE.

JOHN D. LITLE, OF PETALUMA, CALIFORNIA, ASSIGNOR OF ONE-HALF OF HIS RIGHT TO GULLIK O.

DlVlDlNG-COMPASS.

SPECIFICATION forming part of Letters Patent No. 229,619, dated July 6, 1880.

To an whom it may concern:

Be it known that I, JOHN D. LITLE, of Petaluma, county of Sonoma, and State of California, have invented an Improved Dividing- Compass; and I hereby declare the following to be afull, clear, and exact description thereof.

My invention relates to certain improvements in that class of compasses used by carpenters and others as dividers, and having an adjusting and retaining arrangement.

My improvements consist in a peculiar means of securing the moving leg of the compass to the are by which the points of said compass are kept at any desired point, and in certain details of construction, which are more fully described in the accompanying drawings, in which- Figure 1 is a view of my invention. 2 is an edge view.

In the ordinary carpenters compass an arc is attached to one leg and passes through a slot in the other leg, a set-screw passing into this slot, so as to impinge on the side of the arc and secure the moving leg to the arc. After a measurement has been taken this setscrew is turned and the measure retained. In doing this both hands must be used, one to open or adjust the compass, and the other to Fig.

wears out rapidly and does not always work satisfactorily.

In my improved method of securing the moving leg to the arc only one hand has to be used to manipulate both compass and retaining device, this retaining device being of such a character, as to be very durable and easily operated.

Let A represent the legs of a pair of ordinary carpenters dividing-compasses, with its arc B secured to one leg with. the usual set screw and spring, and passing through the slot in the other leg, as shown. This are B, I

form in a peculiar'manner, one of its sides being beveled, as shown, and its lower edge, 12, corrugated or roughened. The lower edge of the slot through which it passes is correspondingly corrugated. v The slot through which the arc moves is somewhat extended, so as to (No model.)

admit of the interposition of a retaining-lever,

O, which is swiveled in said slot above the arc. The lower end of said lever is wedgeshaped, as shown at 0, and moves in the slot on the side of the are which is beveled. The upper end of the lever is formed with a thumbpiece, as shown.

These compasses may be taken in the hand, the legs passing between the fingers, and then the thumb-piece of the lever comes in proper position for the thumb to press or draw upon it. The points are first adjusted by the fingers to take a measurement, and when at the right distances apart the lever is depressed by the thumb. The wedgeshaped end of the lever, moving against the beveled or wedge-shaped side of the arc, pushes said are downward 6 slightly, so its lower corrugated edge engages with the corrugated face of the slot. The wedge of the lever thus locks the arc in that position and the compass-legs are retained at the proper distance apart. To release the are the lever is moved back by the thumb, the wedge being withdrawn from the slot so as to allow the arc freedom of motion. This retaining-lever will lock the are firmly and fix the compass, only one hand being used to handle both compass and lever. It is possible to make a very accurate adjustment in this manner.

Having thus described my invention, what I claim as new, and desire to secure by Let 8o ters Patent, is-

l. Aretainingdevicefor dividing-compasses, consisting. of a beveled are upon which awed geshaped lever is adapted to impinge, substantially as and for the purpose herein described.

2. In combination with the compass A, the beveled corrugated arc B, and the thumblever O, with its wedge 0, whereby the compasses are retained at any desired distance apart, substantially as herein described.

In witness whereof I have hereunto set my hand.

JOHN D. LITLE. Witnesses:

CHAS. G. YALE, FRANK A. BROOKS.

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