US1118693A - Pencil-holding means for pencil-sharpeners. - Google Patents

Description

G. C. SPENGLER.

PENCIL HOLDING MEANS FOR PENCIL SHARPENERS.

APPLICATION FILED JAN. 24. 1912.

Patented Nov. 24, 1914.

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Al 786 C 495' 5B) [er 20 F W UNITED srrarss PATENT. oFFioE.

CHARLES C. SPENGLER, OFROCKFORD, ILLINOIS, ASSIGNOR TO AUTOMATIC PENCIL SHARPENER COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF NEW YORK.

PENCIL HOLDING MEANS FOR, PENGIL-SI'IARPENERS.

To all whom it may concern:

Be it knownthat I, CHARLES C. SPENGLER,

a citizen of the United States,residing at Rockforckin the county of Winnebago and State of Illinois, have invented certain new and useful Improvements in Pencil-Holding Means for Pencil-Sharpeners, of which the following is a specification.

This invention relates to chucks to be used on pencil sharpeners for the purpose of holding. and rotating the pencils that are being sharpened. In some of the pencil holders or chucks heretofore produced, the jaws are pressed inwardly to grasp the pencil by means ofeither leaf or coiled springs. I These prior chucks, however, have been found unsatisfactoryin practice for the reason that they grip different sizes of pencilsto be sharpened with different degrees of force. To operate satisfactorily the chuck must grip the pencil with suflicient force to insure rotation of the latter therewith, but not tightly enough to prevent the pencil from beingdrawn or fed downwardly'to the cuttingfmeans. In previous chucks, if the relation of parts was such that a small-sized pencil would be gripped firmly enough to insure rotation of the pencil, then a large-sized pencil would be held so tightly that proper downward feeding movement thereof could not be had. On the other hand, if the chuck gripped a largesized pencil lightly enough to permit free downward feeding movement thereof, a small-sized pencil would not be engaged with suflicient force to cause rotation thereof with the chuck.

It is the object of my invention to produce a chuck which will grip all sizes of pencils with substantial uniformity. As ancillary to the main object of the invention it is my purpose to provide a chuck of simple and durable construction and one which is inexpensive to manufacture. a

In the accompanying drawings, Figure 1 is a front. elevation of a pencil sharpener equipped with a pencil chuck embodying my invention. Fig. 2 is a fragmental vertical section on line 2 of Fig. 1. Fig. 3 is a vertical section of the chuck with a large pencil Specification of Letters Patent.

Application filed January 24, 1912. Serial No. 673,094.

Patented NOV. 24, 1914.

inserted. Fig. -l is avertical section ofthe chuck with a small pencil inserted. Fig. 5 is a cross-section of the chuck and pencil on the line 5 5 of Fig. 3. Fig. 6 is a fragmental plan view of the chuck with the pencil in sorted and a portion of the casing broken away to show details of the chuck.

The pencil sharpener to which my improvements are herein shown as applied is of the type illustrated in the Gilfillan Patent No. 832,054, issued October 2, 1906. But it is to be understood that the chuck is not limited in its use to any particular form of pencil sharpener.

abase l in which is slidably mounted the The sharpener comprises i drawer 2,.the upper wallofsaid base having an opening 3 therein through which the shavings and dust from the pencils fall into the drawer 2. Surrounding the opening3 are guard walls at. Mounted upon the top wall of thebase 1 is a disk 5 having a plane face 5 on one side and havinga boss 6 formed upon its opposite side. Through this boss extends an opening or bore 7 adapt The opening .Textends at form, that herein shown comprising a plurality of rotating blades 8 lying against the face 5 of the disk 5, saidblades arranged to be rotated by means of a suitable crank handle 9 to move successivelyover the open lower end of the bore 7 so as to cut off the portion of the pencil protrudingthi'ough said lower end. As each knife cuts off a portion of the pencil it draws the pencil bodily downward a slight distance.

"lhe'means for frictionally engaging the pencil A to rotate the latter, which I desig nate as the chuck, is rotatably,mountedupon the upper end of theboss 6, saidineans com pr1s1ng,j1n the present embodiment, a sleeve 10 having an extension 1.1v at its lower end, i

whiclniin this instance,isjseatedlin a countersink in the upper end o'f the opening or bore 7. Fixed upon the extension 11 is a toothed wheel 12 adapted to be engaged by ion any suitable means for intermittently rotating the pencil holder or chuck. A member 13 having spring arms li lies at opposite sides of the sleeve 10 and engages the upper side of the toothed wheel 12 for the purpose of holding the extension 11 seated in the countersink, and also to frictionally hold the sleeve against rotation through momentum.

The sleeve 1.1 has a'plurality of openings 15 in its sides, above which and suitably at tached to said sleeve, is an annular flange 16. A housing or cap 17 is secured to the flange 16 in any suitable way as by means of screws 18 threaded into said flange. housing incloses the upper portion of the sleeve 10- and the gripping means to be now described.

The gripping means comprises a plurality (in this instance four) of fingers or jaws 19, which, in the exemplary embodiment herein disclosed, take substantially the. form of the letter U. The upper or free end of one of the arms 20 of each jaw is pivotally attached to the chuck in any suitable manner, that herein shown comprising a plurality of notches 21 in the periphery of the flange 16 and above the openings 15, the free ends of the arms 20 of the jaws lying in these notches and each having lugs 22 overlying the edges of the notches and engaging the upper surface of the flange 16. Bosses 23 formed in the housing 17 provide chambers 24% in which the upper ends of the arms 20 he, said chambers serving to hold said upper ends in proper position, but permitting the necessary movement thereof. The other arm 25 of each of the jaws 19 is reduced at its free end,as at 26, to provide shoulders 27. Surrounding the reduced ends 26 of the arms 25 and bearing at one end against the shoulders 27 are coiled springs 28, the other ends of which bear against the housing 17.

- Thefingers 1 9 and springs 28 normally ex tend diagonally with respect to the sleeve 11. By a comparison of Figs. 3 and 4, the

former figure showing a large pencil and the latter figure a small pencil inserted into the chuck, it will be noticed that when the jaws 19' are forced to their outermost position by a large pencil, the direction of force exerted by the springs 28- is more nearly parallel to the jaw than :when a small pencil is inserted, as shown in Fig. i. As the jaws are forced outwardly from their innermost position the direction ofpressure of the springs 28 gradually shifts, from a line more or less transverse to the extent of the jaws, toward a line parallel to the jaws. By reason of this operation of the springs and jaws the,

eflfective gripping action of the jaws upon the pencil is maintained substantially constant for all sizes of pencils. This is due to the fact that the force of the springs actu- Said.

ally transmitted to the jaws when in their outer position is less than when in their innermost position, because in the former pos tion the springs act more nearly in a line with the jaws, and thus exert part of their force in pulling downwardly on the pivots of the jaws, while in the latter position the springs act in a direction at a greater angle with respect to thejaws. And this direction of pressure of the springs gradually shifts as the jaws are moved one way or the other, with the result that the effective gripping pressure of the jaws is maintained constant for all sizes of pencils.

In the operation of thesharpener, apenoil is inserted in the chuck and pressed downward into the opening 7. The knives are rotated by means of the handle 9 and the knives cut the wood from the pencil, and, at the same time, gradually draw the pencil downward until it rests upon the stop 29. Between each cut of the knives the toothed wheel 12 is engaged to move the pencil chuck through a partial rotation.

It should be understood that the invention is not limited to the details of construction herein shown and described, but may be modified in various ways without departing from the spirit and scope of the invention.

I claim as my invention:

1. A chuck for pencil sharpeners having pivoted gripping jaws, and coiled springs acting on said jaws and tending, to swing them inwardly, said springs extending 1on gitudinally alongside of the jaws.

2. A pencil chuck comprising a sleeve adapted to receive a pencil and having openings in its sides, a housing attached to said sleeve, U-shaped .pencil gripping jaws extending through said openings in position to grip a pencil, each of said jaws being pivoted by the free end of one of its arms, and coiled springs each bearing at one end against said housing and at its other end upon the other arm of one of said U-shaped aws.

3. A pencil chuck comprising a sleeve adapted to receive a pencil, and having openings in its sides, a flange fixed to the upper end of said sleeve, a housing secured to said sleeve, a plurality of pencil-gripging jaws extending through said open ings in position to grip a pencil, each of said jaws being of approximate U-shape and having the free end of one of its arms pivotally supported by said flange, and coiled springs each bearing at one end against said housing and at its other end;

against the other arm of one of said U- 10 tioned diagonally with respect to said sleeve,

each of said springs bearing at one end against one of said fingers, and at its other end against said housing.

In testimony whereof I aflix my signature in the presence of two Witnesses.

CHARLES C. SPENGLER.

Witnesses:

GUST IIAKSTROM, EDMUND H. RUK.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. 0.

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