US2979031A

US2979031A - Pencil sharpener

Info

Publication number: US2979031A
Application number: US845168A
Authority: US
Inventors: Phlibotte Gaston
Original assignee: Individual
Current assignee: Individual
Priority date: 1959-10-08
Filing date: 1959-10-08
Publication date: 1961-04-11
Anticipated expiration: 1978-04-11

Description

April 11, 1951 G. PHLlBoT-rE 2,979,031

PENCIL SHARPENER Filed Oct. 8, 1959 Tame/$24 6A sro/v PHL /orrf @y @@fviw 2,979,031 11C@ patented Apr. 11, 1961 PENCIL SHARPENER Gaston Phlibotte, 2218 Visitation St., Montreal, Quebec, Canada Filed ct. '8, 1959, Ser. No. 845,168

1 Claim. (Cl. 1Z0-96) The present invention relates to a pencil Sharpener of the type having a helicoidal cutter blade.

The main object of the present invention is the provision of a pencil Sharpener in which there is a single cutter having a helicoidal vcutter blade and arranged to pull the pencil during cutting instead of repelling the same as in ordinary pencil Sharpeners.

A very important object of the present invention is the provision of a pencil Sharpener of the character described in which the speed of rotation of the cutter around its axis is a multiple of the speed of its circular movement around the pencil, such that the pencil is sharpened within a minimum of turns of the operating member.

Yet another important object of the present invention is the provision of a pencil Sharpener of the character described which is of very simple construction, having a minimum of component parts, and which is relatively inexpensive to manufacture.

Still another important object of the present invention is the provision of a Sharpener of the character described in which one part is duplicated and has two functions so that one can substitute the two parts one for the other, when one part is worn out, as regards one of its functions, while still useful in its alternate function.

The foregoing and other important objects of the present invention will become more apparent during the following disclosure and by referring to the drawings in which:

Figure l is a broken sectional elevation of the Sharpener;

Figure 2 is a cross-section along line 2-2 of Figure 1;

Figure 3 is a longitudinal section of part of the casing andV of the sharpening mechanism;

yFigure 4 is a top plan view of the sharpening mechanism; and

Figure 5 is a cross-section along line 5-5 of Figure 4.

The pencil Sharpener of the present invention comprises a casing 1 having at spaced parallel side walls 2 and end walls 3, the latter being extended by a curved top wall 4 which is provided with a carrying handle 5. The bottom of the casing is closed by a cover plate 6 tightlyhinserted in position and abutting against shoulders 7 formed by the

walls

2 and 3.

The side walls 2 are provided, at about mid-height, with opposed threaded circular openings S which are axially aligned, have an equal diameter and are adapted to receive

caps

9 and 9 in threaded engagement.

Caps 9 and 9' are of identical construction Such that they may be interchanged at either side of the casing 1. Each cap has threads 10 receiving the threads of the opening 8 and a radial flange 11 abutting against the external face of the side wall 2.

The bore of the cap has a stepped shape to form shoulders 12. The cap is further-more provided with gear teeth forming a crown gear 13, the teeth of which are slightly diverging towards the inside of the casing 1.

A pencil bearing block generally indicated at 14 has a circular journal portion 15 journaled within the cap 11 which forms a bearing therefor. Journal portion 15 has a stepped section to conform to the steps 12 of the cap 9 and rotates within said cap. A knurled operating disk 16 is threaded onto the end section 17 of reduced diameter of journal portion 15 and serves to rotate the pencil bearing block 14 relative tothe cap 9 and housing 1. The block 14 comprises furthermore a cradle 18 of trough like section and integrally connected to journal portion 15 by'means of two lateral arms 19. Cradle 18 is extended by sleeve like end portion 20 having stepped cylindrical outer surfaces journaled within the bore of the other cap 9', itself threaded within the opposite side wall 2 ofthe casing 1. The stepped surfaces of the

caps

9 and 9 which serve as bearing member for the pencil bearing block 14 prevent axial displacement of said block and enable easy rotation thereof. Sleeve 20 forms an axially extending bore 21 for the insertion of a pencil P Vto be sharpened. The bore 21 has an outer cylindrical portion which is extended and opens within the groove formed by cradle 18; said groove has an inclined surface portion 22 converging towards the extended axis of the cylindrical bore 21 in a direction away from said bore.

The inclined surface portion 22 terminates short of the journal portion 15 so as to leave a slot in which is inserted a pinion 23 which is mounted for free rotation on an inclined shaft 24 and which meshes with the gear teeth of the crown gear 13 of the cap 9. The shaft 24 consists of a pin tightly fitted within the journal portion 15 and within an axially aligned hole made in an ear 25 depending from the body portion 14 adjacent the connecting arms V19 and disposed radially outwardly from the cradle 18. Y

The pinion 23 in turn meshes with a bevelled gear 26 which is integral with or rigidly secured to a cutter 27 of generally cylindrical shape and having spirally extending cutter blades 28.

The cutter 27 together with its bevelled gear 26 is mounted for free rotation on a shaft 29 which consists of a pin tightly tted within the journal portion 1S and in a through bore of -an extension 30 integral with pencil bearing block 14 adjacent sleeve 20. The stud shaft 29 is inclined with respect to the axis of the bore 21 for receiving the pencil P and is divergent with respect to the shaft 24 of the pinion 23. Thus, the cutter 27 has its cutting blades 28 converging with respect to the abutment surface 22 to grind the pencil P inserted within bore 21 to a fine point.

The cradle portion 18 of the block 14 is shaped such as to provide between the cutter 27 and its surfaces sufiicient clearance for the discharge of the wood and lead shavings. Said shavings fall onto the bottom cover 6 of the, casing 1.

The pencil Sharpener is used as follows: The end to be ground of a pencil P is inserted within bore 21 until it abuts against the cutter 27. The operator disk 16 is then rotated in the usual direction and the pencil which is held against rotation is progressively ground and is pulled towards the disk 16, that is within the machine due to the side on which cutting edges of the spiral threads blades 28 are disposed with respect to the usual direction of rotation of the cutter. As the pencil is ground it slides along the inclined surface 22. Rotation of the bearing block 14 'causes peripheral rotation of the cutter 27 around the pencil so as to engage all the peripheral surface thereof while the cutter itself is rotated with respect to the block 14 about its stud shaft 29 at an increased speed due to the provision of the interposi-tion of the pinion 23. The speed ratio between pinion 23, bevelled gear 26 and crown gear 13 can be selected such as to increase as desired the speed of rotation of the cutter 27 about its axis 29 with respect to the number of turns of the body 3 14 around the pencil P. Thus, increase sharpening speed is obtained as compared to conventional Sharpeners in which the gear 26 is meshing directly with the crown gear '13.

The fact also that the pencil P is pulled inwardly by the cutter 27 facilitates the holding of the pencil.

The Sharpener of the present invention in spite of the fact that it has only a single cutter and is thus less expensive to manufacture, has been found to sharpen pencil with greater eiciency than two-cutter Sharpeners.

Obviously, the operator disk 16 can be'replaced by a crank handle and the sharpening assembly can also be used inassociation with another type of casing than the casing 1 shown, which latter is particularly designed as a portable Sharpener. More specifically, the sharpening mechanism including body 14 and associated parts could very Well be used in association with a bracket for mounting the mechanism to a wall and with a shaving receiving housing suspended from said body 14.

This is possible because the sleeve portion 20 of the block 14 need not be journalled within cap 9 but can be free with respect to the latter, as the journal portion 15 ofthe block 14 provides sufficient bearing surfaces for said block 14.

The entire assembly 14 can be removed from the casing 1 by simply unscrewing cap 9 and pulling the assembly through opening 8, the latter having a sucient diameter for said passage. The casing 1 can be emptied of pencil shavings through opening S.

When the gear teeth 13 of the cap 9 are worn out the latter is very easily replaced by cap 9' and cap 9 substitted in place of cap 9. To accomplish this purpose, the disk 16 is unscrewed from end section 1S of block 14.

While a preferred embodiment in accordancevwith the present invention has been illustrated and described, it is understood that various modifications may be resorted to without departing from the spirit and scope of the appended claim.

What I claim is:

A pencil Sharpener comprising a casing having threaded circular openings of equal diameter in opposite side Walls thereof, interchangeable identical cap elements in threaded engagement with and closing said respective openings, each cap element having a stepped central bore and inclined gear teeth forming a bevelled crown gear at the periphery of said bore adjacent the inside face of the respective cap element, a pencil bearing block disposed within said casing and having stepped end journal portions respectively journalled in said cap elements, one of said end journal portions having a pencil receiving bore made therethrough, the portion of said block intermediate said end journal portions forming a cradle of trough like section having an inclined bottom face extending from said bore and terminating short of the other of said end journal portions to define a slot therewith, an ear outwardly projecting from said cradle adjacent said slot, a pinion extending in said slot, journaled in said ear and in said other of said end journal portions and meshing with said crown gear, a cylindrical cutter rotatably mounted on said block and extending in said cradle for rotation about an axis inclined with respect to the axis of pencil receiving bore and to the axis of said-pinion, a bevelled gear wheel fast with one end of said cutter and meshing with said pinion, and manual means for rotating said block in said cap elements.

References Cited in the tile of this patent v UNITED STATES PATENTS