EP1800895A1 - Pencil sharpener and method for manufacturing the same - Google Patents

Abstract

Pencil sharpener (1) has a handle (3) with a central longitudinal axis, a sharpener insert (4) with a pencil guide channel and a paring blade. Handle has a base to be gripped by a human hand with a thumb and an index finger. The base is surrounded by four wall surfaces. Finger support grooves are arranged in the area of the vertex line of the third wall surface (7). The fourth wall surface serves as a peripheral end surface. First, second and third wall surfaces are formed to suit the inside of a curved human hand. An independent claim is included for a method of manufacturing a pencil sharpener.

Description

The invention relates to a pencil sharpener for sharpening a writing, painting or cosmetic pencil.

Conventional pencil sharpeners typically include a sharpener body into which a tapered pin guide channel is inserted. A laterally arranged on the pin guide channel paring knife carries from a rotating in the pin guide channel pin material, resulting in a sharpening of the pin. For catching Spitzabfall further container sharpener are known in which a tip insert with pin guide channel and paring knife a container is detachably mounted. By loosening the tip insert from the container it can be emptied.

To tip a pin in the manner described, some torque must be applied by a user to turn the pin to be sharpened against the peeling knife.

The invention has for its object to provide a pencil sharpener with improved handling. It is a further object of the invention to provide a method of manufacturing such an improved pen nib.

The first object is achieved by a pencil sharpener, which comprises a handle and a tip insert inserted into the handle with a pin guide channel and a paring knife, wherein the handle is at least partially formed the inner contours of a curved human hand.

The invention is based on the consideration that the handling of a pencil sharpener can be improved by the fact that the coupling of the pen nibbler is improved to the human user. For this purpose, the tip insert is placed in a handle that can be well grasped as such by a human hand. The human-tool interface is further improved by the fact that the handle is at least partially formed on the inner contours of a curved human hand. In other words, the handle has at least partial areas, which are designed to be complementary to the inside of a curved human hand substantially.

Due to the ergonomic design of the pencil sharpener by a handle which is formed in partial areas of the inner surfaces of a curved human hand, an improved power transmission is achieved by the user. Compared to conventional pencil sharpeners, a smaller force input is required to achieve the torque required for the sharpening process. In addition, the force entry deteriorating positions of the pen tip are prevented. The attitude is dictated by the Anformung to the human hand. Bad postures are avoided. The ergonomic design of the pencil sharpener makes it possible in particular children or users with limited manual skills to perform the sharpening process easily and easily. As a side effect of the pencil sharpener is also taken with a handle designed in this way and because of the ease of the pointed process like to hand. Especially children are therefore animated to more frequent tips.

The handle can in principle be formed in different parts of the curved human hand. An Anformung is particularly useful pressure points on which the human hand exerts pressure when grasping an object on this. This can be, for example, the palms or individual finger surfaces as such. If the surfaces of the handle are formed in the vicinity of the pressure grip points of the inner contour of a human hand, so the pencil sharpener is as such good in the hand and is easy to use.

In an advantageous embodiment, the handle comprises a base that can be grasped by the human hand with thumb and index finger with a central longitudinal axis, the base being formed with a thumb rest groove extending transversely to the longitudinal axis and with at least one finger rest groove extending transversely to the longitudinal axis. Since the human hand is designed as a gripping hand, with the thumb opposite the other fingers, this embodiment is appropriate, since in this way the handle between the thumb and at least one of the remaining fingers can be kept good and strong. For this purpose, it is sufficient if the handle extends along the longitudinal axis in the most minimal case over a distance of the dimension of about a finger thickness. In this case, the handle of the pen nib would have a flat base of approximately oval cross-section, at the edge of which the thumb rest groove and the finger rest groove are formed opposite one another.

In an advantageous embodiment of the invention, the handle is extended in the direction of the longitudinal axis, so that the base of the thumb rest groove opposite a plurality of parallel Fingerauflagerillen can be formed. In this case, the base at the point at which the finger support grooves are formed, the inner contour of the human hand is formed by the fact that the Fingerauflagerillen are separated from each other by intermediate webs. In this way, the handle fits into the surrounding this hand.

In a further advantageous embodiment of the invention, the handle is substantially formed by the body formed by the interior of a curved human hand. For this purpose, the base around the longitudinal axis substantially of a first, a second, a third and a fourth wall surface to rotate, wherein the wall surfaces are soft in the circumferential direction formed merge into one another. Each of the four wall surfaces has a specific area characteristic. The surface characteristic, ie the position and shape of the surface in three-dimensional space, can be, for example, from wall surface to wall surface in the curvature both in the direction of the longitudinal axis and in the circumferential direction, as well as in introduced surface structures such as Fingerauflagerillen, In particular, the first wall surface corresponds to a thumb rest surface in which the thumb rest grooves are inserted. The second wall surface corresponds to a thumb ball support surface and lies with an enclosed base of the thumb ball and possibly a part of the metacarpal of the human hand. The third wall surface forms a finger support surface, in which in particular the finger support grooves are formed. The fourth wall surface is formed as a peripheral end surface whose dimension is determined by the circumference of the base. If the base can be completely encompassed by a human hand, then the fourth wall surface can only be designed to form the transition between the first and third wall surfaces. If the base is dimensioned such that it can not be completely encompassed by a human hand, then the fourth wall surface corresponds to the open part of the base which lies between the thumb and forefinger of the human hand and which is not engaged.

To support the thumb bale, the second wall surface or the surface of the thumb ball is saddle-shaped. For this purpose, the thumb ball support surface in the direction of the longitudinal axis has a concave and in the circumferential direction a convex curvature.

In an advantageous embodiment, the first wall surface or thumb rest surface is also saddle-shaped. This creates a concave curvature of the thumb rest surface in the longitudinal direction through the introduced thumb rest groove. The curvature of the thumb rest surface in the circumferential direction is convex with a small curvature to flat.

In an advantageous development of the invention, the third wall surface or finger support surface has a substantially arcuate cross section with a vertex transversely to the longitudinal axis. In this case, the or each finger support groove is formed at the vertex, so that the vertex line running parallel to the longitudinal axis on the wall surface has a wavy course. The remaining surface area of the third wall surface is essentially smooth. In this embodiment, the finger support grooves with the intermediate webs form the bearing surface for the finger area of the back finger bones. These stand opposite the thumb in the case of a loosely curved human hand. In other words, by such a base of the handle for a loosely enclosing hand pressure grip points formed in the area of the rear finger bones, whereby an ideal force input can be made for the purpose of sharpening. The handle is in this way ergonomically in a loosely curved human hand. Due to the fact that the finger rest grooves are arranged substantially in the region of the apex line of the third wall surface, a malposition of the pen nibbler is reliably avoided.

As stated, the fourth wall surface serves as a peripheral end surface. While first, second and third wall surface are formed with appropriate dimensioning of the base of the handle the inner sides of a human hand, the design of the fourth wall surface remains open. Depending on whether the first, second and third wall surface are arranged in the circumferential direction in a clockwise or counterclockwise direction, a pencil sharpener is created for left-handed or right-handed people.

If the fourth wall surface is shaped similar to the second wall surface, a uniform design of the handle is advantageously possible both for left-handed and for right-handed users. In this case, the fourth wall surface for a left hand forms a peripheral end surface that is not gripped by the hand. The second wall surface is hereby shaped as the thumb ball support surface. For a right hand, the fourth wall surface but at the same time forms a thumb ball support surface and is formed, for example saddle-shaped. The second wall surface then has the function of the peripheral end surface and is not encompassed by the human hand. By the specified embodiment of the handle, it is thus possible to provide a uniform pen sharpener, which has an ergonomically designed handle for both left and right handed.

Conveniently, the base of the handle is integrally formed on the longitudinal axis a vertical, overhanging upper plateau surface. This ensures that the expended against the hand in the direction of the longitudinal axis of the pressure does not lead to slipping of the handle in the hand. This is safely prevented by the overhanging upper plateau surface, as it rests on umgriffener base of the curved human hand.

Appropriately, the overhanging part of the upper plateau surface finger recesses are molded for support on the thumb and forefinger. As a result, individual pressure points on the human hand are prevented, which would be uncomfortable for the user in the execution of the sharpening process. This also leads to an improvement of the interface between human hand and tool.

To set up the pen tip, it is advantageous if the base is formed a perpendicular to the longitudinal axis extending flat lower bearing surface. If the lower bearing surface consists of two mutually tilted flat surfaces, this can save material of the handle. At the same time, this embodiment allows a parking of the pen tip in two possible positions. Also, a free, not guided in a finger rest groove fingers of the inclined surface can be placed comfortably.

Advantageously, the tip insert is inserted approximately centrally parallel to the longitudinal axis in the base. As a result, an ideal force entry is achieved by the human hand in the pen sharpener for applying the torque required for the sharpening process.

In further advantageous embodiments of the invention, the tip insert is inserted into a bore for receiving Spitzabfall. To remove the spike, either the point insert may be releasably inserted, or the hole passes through the base in full length so as to face the point insert at the bottom of the base a lid for emptying the bore can be attached.

In a further advantageous embodiment, the handle comprises materials of different elasticity. Thus, the handle may have a material of high elasticity and otherwise a material of lower elasticity at the points of the hand pressure points. The softer, higher elastic material in this case gives the hand pressure points, while the harder material of lower elasticity controls the predetermined handle loading. As a result, an optimal gripping position can be specified.

The second object is achieved by a method for producing a pen tip, wherein a substantially cylindrical body is provided in approximately the dimension of a human hand from a moldable mass with a space for the point insert space creating placeholder, the body is firmly grasped by hand, whereby the body is formed at least a part of the inner contours of a human hand, wherein the molded body is optionally used with removed placeholder either as a raw template, with the help of a shaping processing technology, in particular a casting, casting, injection, rotary, Milling or laser processing technology, the handle is made, or the molded body is cured to the handle, wherein the placeholder is optionally taken before or after curing and wherein in the placeholder or in the space created by the placeholder opening a spike is used.

By this manufacturing method, it is possible in a simple manner to provide a pencil sharpener having a handle which is partially formed on the inner contours of a curved human hand. The handle is created in a sense as an imprint of the human hand. For this purpose, it is possible in a known manner to use the impression of the human hand as a basic or raw form for other common manufacturing technologies. In particular, a negative or casting mold can be produced from the raw form be made by which, for example by means of plastic injection molding the handle for the pencil sharpener. In this variant, the once created impression of the human hand is used as a template for a serial manufacturable pen sharpener.

Alternatively, it is also possible to make each one of the pencil sharpeners by grasping the body by the later user himself, by the human hand, thereby molding his own hand into the handle of the pencil sharpener. Curing the molded base of the handle creates a user-friendly pencil sharpener that fits perfectly in your own hand.

For curing the molded body, this advantageously comprises a plasticine made of a duroplastic, which can be molded in a soft form, the human hand. Subsequently, the body is cured, for example by a temperature treatment, which may optionally be carried out in a domestic oven. The personal pencil sharpener lies perfectly in the user's hand, resulting in a good force input to achieve the torque required for the sharpening process. In particular, children are thereby animated too frequent tips.

In a further advantageous embodiment, materials of different plasticity are used for the moldable mass. By a predetermined distribution of materials of different plasticity in the cylindrical body a certain influence on the shape can be achieved. In particular, the use of a material of high plasticity and a material of lesser plasticity allows to achieve certain points with high ductility, while other places are more likely to retain the original shape. For example, if the material of high plasticity on the outside of the cylindrical body and the material of lesser plasticity in the interior of the cylindrical body used, so gives the softer material in the shaping by the human hand the hand pressure points while the harder material controls the handle shape as such.

In the production of the pencil sharpener, in particular those materials can be used which have a different elasticity in the final state.

Fig. 1 bis 4

in einer dreidimensionalen Darstellung jeweils einen Stiftspitzer mit einem teilweise den Innenkonturen einer gekrümmten menschlichen Hand angeformten Handgriff (aus verschiedenen Blickrichtungen),

Fig. 5

schematisch den Stiftspitzer gemäß den Fig. 1 bis 4, wie er von einem menschlichen Hand umgriffen wird, und

Fig. 6

in einem Längsschnitt den in den Stiftspitzer integrierten Spitzeinsatz mit einer Bohrung zur Aufnahme von Spitzabfall.

Embodiments of the invention will be explained in more detail with reference to a drawing. Show:

Fig. 1 to 4

in a three-dimensional representation in each case a pencil sharpener with a part of the inner contours of a curved human hand molded handle (from different directions),

Fig. 5

schematically the pencil sharpener according to FIGS. 1 to 4, as it is encompassed by a human hand, and

Fig. 6

in a longitudinal section of the integrated into the pen sharpener tip with a hole for receiving Spitzabfall.

1 to 4, a pencil sharpener 1 is shown from different viewing directions in a three-dimensional representation, comprising an ergonomic handle 3 and a pin insert 4 inserted into the handle 3. The pin insert 4 is here inserted centrally substantially along the longitudinal axis of the handle 3. Also shown is a pin 6, as it is used for tips in the pin guide channel of the pin insert 4. At the same time, the pin 6 defines the longitudinal axis of the handle 3 or its base which can be grasped by the hand.

The base running along the longitudinal axis is circulated in total by four wall surfaces with characteristic properties.

In Fig. 1, the handle 3 is shown with a view of the third wall surface 7. The third wall surface 7 is formed as a finger support surface and has for this purpose introduced Fingerauflagerillen 8 and between the Fingerauflagerillen 8 extending webs 9 on. The third wall surface 7 has further perpendicular to the longitudinal axis, which is defined by the pin 6, a substantially arcuate course with a vertex. This is evident from the drawn contour line 10. The Fingerauflagerillen 8 are each attached to the vertex, so that there is a wavy crest line at this point in the direction of the longitudinal axis. On both sides of the Fingerauflagerillen 8, the third wall surface 7 is formed substantially flat.

The base of the handle 3, an upper plateau surface 11 is formed, which has a circumferential overhang 12. By the overhang 12, the plateau surface 11 of the base of the handle 3 is over, creating a support surface is created for the hand enclosing the hand. As a result, the pressure necessary for the sharpening process can be easily generated in the direction of the pin 6 or in the direction of the longitudinal axis.

Fig. 2 shows the pen sharpener 1 from another viewing direction. Compared with Fig. 1, the third wall surface 7 is rotated away to the left. You can still see the Fingerauflagerillen 8 and the intermediate webs 9. One looks obliquely from below against the underside of the upper plateau surface 11. To avoid pressure points of the underside of the upper plateau surface 11 finger recesses 14 are formed.

From the viewing direction shown in FIG. 2, the second wall surface 16 of the base of the handle 3 can be seen. The second wall surface 16 is substantially saddle-shaped. One recognizes the convex curvature in the circumferential direction and the concave curvature in the direction of the longitudinal or pin axis. Since the third wall surface 7 or finger support surface is arranged to the left of the second wall surface 16 or the surface of the thumb ball, the illustrated pencil sharpener 1 is designed ergonomically for a left-hander.

At the end opposite the pin 6 or the tip insert 4, the handle 3 has a flat lower bearing surface 18.

In Fig. 3, the pencil sharpener 1 is again shown from another direction. It can be seen now that the third wall surface 7 or finger support surface at the bottom of the handle 3. From this representation it is apparent that the lower support surface 18 consists of two mutually bevelled part levels. In Fig. 3, the upwardly inclined tilted part plane 18 'can be seen.

One looks at the third wall surface 7 or finger support surface opposite first wall surface 20, in which a thumb rest 21 is formed. The thumb rest 21 is formed substantially flat in the circumferential direction. Overall, a saddle-shaped shape of the first wall surface 20 results.

Between the first wall surface 20 and the third wall surface 7, the fourth wall surface 23 can be seen. This has, as can be seen from the drawn contour line 24, a convex curvature in the circumferential direction and a concave curvature in the longitudinal direction. In other words, the fourth wall surface 23 is similar to the second wall surface 16, namely saddle-shaped configured. If a right-handed person grasps the illustrated pencil sharpener 1, the fourth wall surface 23 serves as a thumb-ball support surface. The second wall surface 16 is exposed in this case between the thumb and the remaining fingers and then acts as a peripheral end surface. The pencil sharpener 1 shown is thus ergonomically shaped both for a left-handed and for a right-handed person.

From the viewing direction shown in FIG. 4, in particular the first lateral surface 20 with a molded-on thumb rest 21 can be seen. The design of the lower support surface 18 with a tilted part plane 18 'is clearly visible.

In Fig. 5 of the pencil sharpener 1 shown in Figs. 1 to 4 is shown as it is encompassed by a human left hand 26 schematically. One recognizes those in the human hand-based base 31 of the handle 3. The contour of the base 31 is formed by the first, second, third and fourth wall surface 20, 16, 7 and 23 respectively. Here, the first wall surface 20 is the thumb 29, the second wall surface 16 of the thumb ball, the third wall surface 7 of the fingers (shown are index finger 27 and middle finger 28) on; the fourth wall surface 23 serves as a peripheral end surface. It is not enclosed by the hand 26.

Next you can see the base 31 of the handle 3 molded upper plateau surface 11, which rests on the human hand 26 on the surface formed by the thumb 29 and index finger 27. The outline of the plateau surface 11 is shown here by dashed lines.

The tip insert 4 is inserted into the pencil sharpener 1 centrally in the base 31 of the handle 3. The pin insert 4 has two pin guide channels 33 with different diameters. In each of the pin guide channels 33, which are formed tapered, a paring knife 34 is used in each case to the tips of a pin used.

FIG. 6 shows the pencil sharpener 1 with an ergonomically designed handle 3 in a longitudinal section. The tip insert 4 with pin guide channel 33 and paring knife 34 is inserted by means of a cover 35 in a bore 37. The bore 37 is centrally inserted in the base 3 of the pen point 1. The lid 35 is removable for emptying the bore 37 of spiked waste.

In a alternative shown in dashed lines, the bore 37, which receives the tip insert 4, extends to the lower support surface 18. Here, the bore 37 is closed by means of a removable cover 38. In the dashed variant, the tip insert 4 can be firmly mounted in the handle 3. The bore 37 is emptied of garbage by the lid 38 is opened.

LIST OF REFERENCE NUMBERS

1

pencil sharpener

3

handle

4

sharpener insert

6

pen

7

third wall surface

8th

Finger support grooves

9

Stege

10

contour line

11

upper plateau surface

12

overhang

14

finger grooves

16

second wall surface

18

lower support surface

18 '

tilted part plane

20

first wall surface

21

Thumb support groove

23

fourth wall surface

24

contour line

26

human hand

27

index finger

28

middle finger

29

thumb

31

Base

33

Pin guide channel

34

paring knife

35

cover

37

drilling

38

cover

Claims (21)

A pencil sharpener (1) comprising a handle (3) and a tip insert (4) inserted into the handle (3) with a pin guide channel (33) and a paring knife (34), the handle (3) at least partially reflecting the inner contours of a curved human Hand (30) is formed. A pencil sharpener (1) according to claim 1,
the handle (3) comprising a base (31) having a central longitudinal axis graspable by the human hand (26) with thumb (29) and forefinger (27), and wherein the base (31) has a thumb rest groove (33) extending transversely to the longitudinal axis ( 21) and their opposite at least one extending transversely to the longitudinal axis Fingerauflagerille (8) are formed. A pencil sharpener (1) according to claim 1 or 2,
wherein the base (31) of the thumb rest groove (21) is formed integrally with a plurality of parallel finger rest grooves (8), and wherein the finger rest grooves (8) are separated from each other by intermediate lands (5). A pencil sharpener (1) according to claim 2 or 3,
wherein the base (31) about the longitudinal axis substantially from a first (20), a second (16), a third (7) and a fourth wall surface (23) is circulated, wherein the wall surfaces (20,16,7,23 ) are smoothly formed into one another in the circumferential direction, wherein in each case the first (20) and third (7) and the second (16) and fourth wall surface (23) are substantially opposite, wherein the thumb rest groove (21) in the first (20) and the or each Fingerauflagerlage (8) in the third wall surface (7) is formed, and wherein the second wall surface (16) is formed substantially saddle-shaped to support the thumb bale. A pencil sharpener (1) according to claim 4,
wherein also the first wall surface (20) is saddle-shaped. A pencil sharpener (1) according to claim 4 or 5,
wherein the third wall surface (7) has a substantially arcuate cross-section with a vertex transverse to the longitudinal axis, wherein the or each Fingerauflagerille (8) is formed to the vertex, so that on the wall surface (7) parallel to the longitudinal axis extending apex line a wave-shaped course has, and wherein the remaining surface area is substantially smooth. A pencil sharpener (1) according to any one of claims 4 to 6,
wherein the fourth wall surface (23) is shaped similar to the second wall surface (16). A pencil sharpener (1) according to one of claims 2 to 7,
wherein the base (31) has a vertical to the longitudinal axis, overhanging upper plateau surface (11) is integrally formed. A pencil sharpener (1) according to claim 8,
wherein the overhanging part (12) of the upper plateau surface (11) on the underside finger recesses (14) are formed for resting on the thumb and forefinger. A pencil sharpener (1) according to any one of claims 2 to 9,
wherein the base (31) has a perpendicular to the longitudinal axis extending flat lower bearing surface (8) is formed. A pencil sharpener (1) according to claim 10,
wherein the lower support surface (8) is formed from two mutually tilted flat surfaces (eg 8 '). A pencil sharpener (1) according to any one of claims 2 to 11,
wherein the tip insert (4) is inserted approximately centrally parallel to the longitudinal axis in the base (31). Pencil sharpener (1) according to one of the preceding claims,
wherein the tip insert (4) is inserted into a bore (37) for receiving spiked waste. A pencil sharpener (1) according to claim 13,
wherein the tip insert (4) for releasing the bore (37) is detachably inserted. A pencil sharpener (1) according to claim 13 or 14,
wherein the handle (3) has on its underside a closable opening for emptying the bore (37). Pencil sharpener (1) according to one of the preceding claims,
wherein the handle (3) comprises materials of different elasticity. A pencil sharpener (1) according to claim 16,
wherein the handle (3) comprises a material of high elasticity and a material of lower elasticity. A method of making a pen nib (1) according to any one of claims 1 to 17, comprising the steps of: a substantially cylindrical body approximately the size of a human hand (26) of a moldable mass is provided with a placeholder creating space for the point insert (4), the body is grasped firmly by hand, whereby the body is formed at least part of the inner contours of a human hand (26), - The molded body is optionally used with removed placeholder either as a raw template, by means of a shaping processing technology, in particular a casting, casting, injection, turning, milling, or laser processing technology, the handle (3) is produced . - or the molded body is cured to the handle (3), wherein the placeholder is optionally taken before or after curing, - In the placeholder or in the resulting from the placeholder opening a tip insert (4) is used. Method according to claim 18,
wherein the moldable mass comprises a thermoset kneading material, and the shaped body is cured by means of a temperature treatment to the handle. Method according to claim 18 or 19,
wherein the moldable material materials of different plasticity are used. Method according to claim 20,
wherein a material of high and a material of lesser plasticity are used.

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