FR2720034A3 - Spring-driven pencil sharpener - Google Patents

Abstract

A cap (1) has an opening (11) to receive a pencil, a flexible clamp (15) and a pair of rectangular holding pins (16) for retaining the pencil. A main body is formed of a pair of castings (20), each with a lateral cover (3), containing a sharpening blade set (4) and a spring-driven powering device 5 to drive the blade set to rotate and sharpen the pencil. The spring in the device (5) is wound-up by a cord (56) which, when released, drives the blade set. Ratchet mechanisms are associated with the ends of the spring provide for spring wind-up and blade set rotation. Springs (142) on posts (14) carried by the cap (1) urge a pencil retained by the cap into engagement with the blade set (4) when the cap is moved outwardly relative to the main body.

Description

SPRING-CONTROLLED PENCIL SHARPENER

FIELD OF THE INVENTION

  The present invention generally relates to a pencil sharpener and more particularly to a spring-controlled pencil sharpener.

  TECHNOLOGICAL BACKGROUND OF THE INVENTION

  Usually a pencil sharpener is controlled electrically or manually. In the case of an electric pencil sharpener, a power source is required to control the device. The need for electricity somewhat restricts the application of

electric pencil sharpener.

  In the case of a manual pencil sharpener, the user must use both hands to hold the pencil sharpener and at the same time operate the sharpening blade. Operation may be difficult, especially for children who represent the

  most potential users.

SUMMARY OF THE INVENTION

  Consequently, the first object of the present invention is to propose a pencil sharpener controlled by

  spring which solves the problems of the previous art.

  According to the object mentioned above, the present invention makes it possible to provide a spring-operated pencil sharpener comprising a pencil sharpener holder and a device

  control spring to control the sharpening of the pencil.

  And also, the outer envelope of the present invention is preferably designed in the shape of an egg so that it can be held easily and present an appearance

pleasant.

  The above object, features and advantages of the invention will become quite apparent from

  of the following detailed description which should be read in

relationship with the attached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

  Figure 1 is a perspective view of the spring-operated pencil sharpener constructed in accordance with the present invention; Figure 2 is an exploded perspective view of the spring-operated pencil sharpener of Figure 1; Figure 3 is a cross-sectional view showing the means for holding the pencil of the spring-operated pencil sharpener in the state where the pencil is disengaged; Figure 4 is a cross-sectional view showing the means for holding the pencil of the spring-operated pencil sharpener in the state in which the pencil is engaged; Figure 5 is an exploded perspective view of the spring control device of the spring-operated pencil sharpener; Figure 6 is a cross-sectional view showing the operation of the spring-operated pencil sharpener; and Figure 7 is a cross-sectional view showing the state in which the pencil sharpening operation is

  complete with the pencil sharpener of the present invention.

  DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

  Referring to the drawings, a spring-operated pencil sharpener assembly constructed in accordance with the present invention is shown. With particular reference to FIGS. 1 and 2, the spring-operated pencil sharpener comprises an upper cap 1 whose shape resembles that of an airplane nose, means for holding the pencil comprising a flexible lock 15, a pair of retaining pins 16 and a pair of bolts 17. The cap 1 forms an interior space receiving the latch 15 and is moreover fixed from below by the nuts 17. The cap 1 has a pair of first rectangular notches 12 placed opposite one another on the side wall to receive respectively a portion of the

lugs 16.

  The cap 1 having a circular opening 11 formed at its upper part to allow the pencil to pass (see FIGS. 3 and 4), comprises a pair of side wings 13 descending from the bottom of the cap and a pair of uprights 14 which are in addition respectively fixed to the wings 13. Each of the uprights 14 comprises a flange 141 placed at its free end for retaining a first spring 142. The cap 1 further comprises a pair of interior projections directed downwards lla. Each projection l engages so as to be able to disengage an upper rectangular cavity 161 placed on each of the lugs of

maintenance 16.

  The latch 15, which is preferably made of flexible metal, has the shape of a cross having a first central notch 151 arranged at the point of intersection to allow the pencil to pass, a pair of first lateral notches 152 disposed on a branch of the cross and adjacent to two opposite sides of the notch 151, a pair of second rectangular lateral notches 153 disposed on the other branch of the cross and adjacent to the two opposite sides of the notch 151, and two end portions in tooth-shaped 154. Each of the two tooth-shaped end portions 154 is bent down around the central axis of each of the second rectangular side notches 153 to be parallel to the central notch 151 so that the latch 15 is considered laterally as a two-layer structure. Thus, the two tooth-shaped end portions 154 form a locking notch 155 below the central notch 151 for

  let the pencil pass and hold it inside.

  Each of the rectangular retaining lugs 16, which has a lateral rectangular cavity 162 at one end for tightening and holding the lower layer of the latch 15, the structure of which is two layers, comprises a ball 163 disposed at its other end and having a bottom

  rough to be able to grip properly.

  Normally, the diameter of the locking notch is less than that of the pencil so as to keep the pencil passing through it tight. The height of the first rectangular notches 12 of the cap 1 is greater than that of the rectangular retaining lugs 16. Thus, as shown in FIG. 3, when the lugs 16 are forced to tilt upwards so that the upper cavities 161 engage, so that they can be released, respectively, the internal projections lla of the cap 1, the two tooth-shaped end portions 154 of the latch 15 are separated so as to widen the notch

  locking device 155 so that the pencil can pass through it.

  And, as shown in FIG. 4, when the lugs 16 are forced to act on the upper cavities 161 so that they disengage the internal projections lla, the flexible latch 15 restores the lugs 16 in their normal positions, which results flexibility and keeps the pencil tight inside the notch

lock 155.

  Referring again to Figures 1 and 2, the spring-operated pencil sharpener further comprises a shell 2 which is constructed with a couple of molded parts which form an interior space, and a pair of side covers 3 which can be s '' open to remove the chips from the sharpening of the pencil and which are respectively connected to

molded parts 20.

  In the interior space of the shell 2, the spring-operated pencil sharpener comprises a pencil blade holder 4 provided with a conical cavity 41 to receive the head of the sharpening pencil and a spring-loaded control device 5. The pencil holder 4 further comprises a lower pawl 42 so that the spring control device 5 controls the holder 4 so that it sharpens the received pencil by means of its engagement with the

ratchet 42.

  One of the molded parts 20 comprises a pair of blocking plates 21 arranged on its inner surface which block so that they can be released in a pair of blocking notches 21a disposed on the other molded part constituting the shell 2. The shell 2 has an upper opening 22 allowing the pencil to pass through and forms an upper chamber 23 to receive there the pencil sharpener blade holder 4 and to store there the shavings of the sharpening of the pencil and a lower chamber 24 to receive there the spring control device 5. The shell 2 also forms a pair of lateral chambers 25 to receive the uprights 14, the flanges 141, and the springs 142 respectively, so that the cap 1 is there

maintained while being able to move.

  Each of the molded parts 20 comprises two parallel horizontal plates 27, 28 mounted inside the chamber 24. The upper plate 27 has a central notch 271 to be locked so as to be able to be released by the control device 5 and the plate lower 28

  is designed to support the control device 5.

  Each of the molded parts 20 further comprises connection means 29 adjacent to the upper opening 22 for pivotally connecting the side cover 3 to the upper part 31 so that the cover 3 can be opened by tilting to evacuate the chips from the sharpening of the pencil produced by the blade holder 4. And the outer shell of the shell 2 is preferably designed to adapt to that of the cap 1 to have an egg shape

  and be held easily and look nice.

  Referring to Figures 2 and 5, the spring control device 5 comprises a ring-shaped cover 51 having an upper opening 511 for receiving the pawl 42 disposed at the bottom of the blade holder 4 and a plurality of projections outer preferably arranged at the circumference to be blocked in rotation by the notch 271 of the inner plate 27 inside the lower chamber 24. The spring control device 5 comprises a pulley 52 controlled by tensioning a rope comprising an upper pawl 521 to engage so that it can be released in the pawl 42 to rotate the blade holder 4 in one direction and a lower retaining element 522, and a second spring 53 held at one end by the lower retaining element 522. The spring control device 5 also comprises a fixing 54 comprising an upper retaining element 541 extending upwards to maintain ir the other end of the second ring 53 and the lower external pawl 542. The spring control device 5 further comprises a base 55 comprising an internal pawl 551 for engaging so that the lower external pawl 542 can be released from the fixing 54 and a rope 56 wrapped around and attached to the pulley 52 controlled by tensioning a rope. The base 55 forms an interior space for receiving the pulley 52 controlled by tension of a rope, the second spring 53 in the compressed state and the

fixing 54.

  Figure 6 is a cross-sectional view showing the operation of the spring-operated pencil sharpener of the present invention. After having pressed the flexible latch 15 to widen the locking notch 155 formed by the two tooth-shaped end portions 154, the user inserts the pencil into the opening 11 of the cap 1, in the notch locking 155, and if necessary in the notch 41 of the blade holder 4 so as to place the head of the pencil inside the blade holder 4 and pulls the uprights 14 of the cap 1 partially out of the side chambers 25 to compress the first springs 142 by the flange 141 so that the inserted pencil is tightened and held in place with the latch 15. The next step consists in pulling the rope 56 towards the outside of the pulley controlled by tension of the rope 52 so as to force the second spring 53 to deform, which results from the holding connection between the second spring 53 and the lower holding member 522 of the pulley controlled by tension of the rope 52, while the attachment 54 is stationary, f how to store the potential energy in the second spring 53. Finally, when it is released, the rope 56 comes back to wind around the pulley controlled by tension of the rope 52 because of the potential energy of the second spring 53 which tends to return to its initial state. Simultaneously, the upper pawl 521 of the pulley controlled by tensioning the rope 52 forces the lower pawl 42 to rotate the blade holder 4 in synchronism with the pulley controlled by tensioning the rope 52 to

sharpen the inserted pencil.

  Figure 7 is a cross-sectional view showing the state obtained when the sharpening of the pencil is complete with the spring-operated pencil sharpener of the present invention. The first springs 142 inside the lateral chambers 25 are relaxed to return to their normal configurations and the cap 1 returns to cover the

shell 2.

  After the description of the preferred embodiment of the

  present invention with reference to the accompanying drawings, it should be appreciated that the present invention is not limited to this particular embodiment and that various changes and modifications may be made to it by those skilled in the art, without departing from the scope or spirit of the invention as defined in

attached claims.

Claims (3)

  1. Spring-operated pencil sharpener comprising an upper cap (1) for passing a pencil and forming an interior space; said cap (1) comprising a pair of uprights (14) being firmly fixed therein in which each of said uprights comprises a flange (141) disposed at a free end to hold therein a first spring; holding means (16) which can be received in the interior space of said cap to let said pencil pass and to hold said pencil by being able to release it so that said pencil passes through said cap and said holding means and is held so as to be able to be released by said holding means; a blade holder (4) provided with an upper cavity for receiving the head of said sharpening pencil therein and comprising a first lower pawl; a spring control device (5) comprising a cover having an upper opening for receiving there through said first lower pawl of said blade holder, a pulley controlled by tension of a rope (56) comprising a first upper pawl for engaging said releasable first lower pawl of said blade holder and a lower retaining element, a second spring held by said lower retaining element at one of its ends, a fixing comprising an upper retaining element extending upwards to hold the other end of said second spring and a second lower pawl, a base comprising an inner pawl to engage while being able to be released said second lower pawl of said fixing, and a rope (56) wound around and attached to said pulley controlled by tension of the rope at one end so that when pulling said rope towards the ex the inside of said pulley controlled by tensioning the rope, said second spring is forced to deform which results from the holding connection between said second spring and said lower element for holding said pulley controlled by tensioning the rope, while said attachment is stationary, so as to store potential energy in said second spring and when the said rope is released and it comes back to wind around the pulley controlled by tension of the rope because of the energy potential stored in said second spring which tends to return to its initial state, said first upper pawl of said pulley controlled by rope tension forces said lower pawl to rotate said blade holder in synchronism with the pulley controlled by rope tension to sharpen said pencil; said base forming an interior space for receiving said pulley controlled by tensioning of the rope, said second spring in a compressed state, and said fixing; a shell (20) having an upper opening for allowing said pencil to pass and forming an interior space which has an upper chamber for receiving and holding said blade holder therein (4), a lower chamber for receiving and maintaining said blade therein spring-loaded control device (5), and a pair of lateral chambers for receiving said pair of uprights (14), said flanges (141), and said first springs so that said cap (1) is held there being able move and when said uprights are partially pulled from said lateral chambers to force said first springs compressed by said flanges, said rod is held fixed with the help of said holding means; and at least one side cover (3) which can be opened to evacuate said chips from   sharpening the pencil and being connected to said shell.   2. Spring-operated pencil sharpener according to claim 1, wherein said cap (1) further comprises a pair of downwardly directed internal projections arranged to engage said retaining means, being releasable, having a pair first notches (12) arranged opposite one another on the side wall to receive partially said holding means.   3. Spring-operated pencil sharpener according to claim 2, wherein said holding means comprise a flexible lock (15) having a second notch for letting through said pencil and a pair of lateral notches (151,152) which arranged therein and comprising two tooth-shaped end portions (154) such that each of said end portions is bent downward around the central axis of each of said side notches to be parallel to said second notch and a two-layer structure and then said two end portions form a locking notch below said second notch to pass the pencil through and retain it therein; and a pair of retaining lugs (16) which can be partially received inside said first notches (12) of said cap, each of them having an upper notch which is arranged therein so as to be able to engage said protrusions interior facing downwards of said cap respectively and a lateral cavity which is arranged at one end to hold therein the lower layer of said two-layer latch (15) and comprising a ball (163) arranged at the other end and having a   rough bottom to be able to grip properly.