Abstract:
The present invention involves a pencil sharpener that is housed in a pencil cap, having a variable-sized shavings reservoir. The shavings reservoir can be expanded by moving at least one of an internal wall, an external wall, and the sharpener. Contemplated caps comprise any suitable dimension, but preferably have a length that is at least 50%, or at least 75%, that of a corresponding full-length pencil.

Description:
FIELD OF THE INVENTION  
       [0001]     The field of the invention is pencil sharpeners.  
       BACKGROUND OF THE INVENTION  
       [0002]     Pencils have been used for many years and are widely distributed. Generally, there are two common types of pencils: wooden pencils and mechanical pencils.  
         [0003]     Wooden pencils suffer from several disadvantages. One disadvantage is that wooden pencils often become blunt upon use. Another disadvantage of wooden pencils is that the lead breaks easily, during both use and transport. Still another disadvantage is that handling wooden pencils is often messy because the lead is usually exposed and can rub off on clothing, hands, and other items. Furthermore, if the lead breaks, disposing of the broken piece of lead becomes a nuisance. This is even more problematic when using cosmetic pencils because the “lead” is so soft and breaks easily.  
         [0004]     One method of overcoming at least some of those disadvantages is to carry several sharpened wooden pencils in order to account for dulling or breaking of the lead. However, carrying several wooden pencils is extremely inconvenient, especially because it is difficult to estimate how many pencils will be needed.  
         [0005]     Mechanical pencils are a partial substitute to wooden pencils. Mechanical pencils eliminate the need to sharpen pencils because the lead is so small that it never needs sharpening. However, mechanical pencils also suffer from several disadvantages. For example, mechanical pencils are not especially useful to artists in shading their drawings.  
         [0006]     Another method of overcoming at least some of those disadvantages is to keep a pencil sharpener handy. However, that solution is also problematic for several reasons. First, one must remember to always keep a pencil sharpener handy. Second, it is inconvenient to have to carry both a pencil and a sharpener, especially when space is limited. Furthermore, sharpening a pencil can be messy, especially if the sharpener does not contain a cavity to catch the shavings.  
         [0007]     Some manufacturers have introduced pencils with attached sharpeners to try to overcome some of those disadvantages. However, those pencil-attached pencil sharpeners still suffer from disadvantages. For example, some pencil-attached pencil sharpeners do not contain a cavity to catch shavings, which would make sharpening the pencil messy and time consuming. Furthermore, in pencil-attached pencil sharpeners, the length of the pencil together with the cap becomes shorter as the pencil is sharpened. Carrying longer pencils is difficult, especially cosmetic pencils that are typically carried in a purse or other small compartment.  
         [0008]     Thus, there is still a need for an improved pencil-attached pencil sharpener.  
       SUMMARY OF THE INVENTION  
       [0009]     The present invention involves a pencil sharpener that is housed in a pencil cap having a variable-sized shavings reservoir.  
         [0010]     In preferred embodiments the shavings reservoir is expanded by moving the sharpener. The pencil sharpener cap can also include a retention mechanism that removably couples the pencil sharpener cap to a corresponding pencil, such as a snap-fit mechanism or a friction or compression collar.  
         [0011]     Contemplated caps can have any suitable dimensions, but preferably have a length that is at least 50%, or at least 75%, that of a corresponding full-length pencil.  
         [0012]     Various objects, features, aspects, and advantages of the present invention will become more apparent from the following detailed description of preferred embodiments of the invention. 
     
    
     BRIEF DESCRIPTION OF THE DRAWING  
       [0013]      FIG. 1  is a vertical cross-section of the pencil sharpener cap coupled to a pencil.  
         [0014]      FIG. 2  is a vertical cross-section of the pencil sharpener cap and a corresponding pencil.  
         [0015]      FIG. 3  is a perspective front view of the pencil sharpener cap coupled to a pencil.  
         [0016]      FIG. 4  is a vertical cross-section of an alternative embodiment of the pencil sharpener cap and pencil. 
     
    
     DETAILED DESCRIPTION  
       [0017]      FIG. 1  generally comprises a pencil sharpener cap  10  that removably receives a pencil  20 . The pencil sharpener cap  10  generally comprises a sharpener  100 , a variable-size shavings reservoir  200 , and a mechanism  300  for changing the size of the shavings reservoir  200 .  
         [0018]     Pencils  20  generally have a relatively hard covering and a relatively soft center. The covering may comprise any plastic, wood, paper, or polymer that sufficiently protects the soft center from breaking or smearing. The “center” of a pencil  20  is sometimes referred to as “lead” although even in drawing pencils, the “lead” is a misnomer and refers to graphite. As used herein, the term “center” can comprise any material or compound including wax, lead, graphite, plastic polymer, drugs, pharmaceuticals, cosmetics, etc. that can be formulated to be delivered through a pencil. Pencils  20  may be any standard or non-standard sized pencil  20 , including narrow to wide diameter pencils. It is especially contemplated that pencils  20  include cosmetic pencils, including eye pencils, lip pencils, and other make-up pencils.  
         [0019]     The sharpener  100  generally comprises a housing  110  and a cutter  120 . The housing  110  may comprise any durable material that is capable of holding pencil  20  in place during sharpening without squashing or damaging the pencil. Thus, contemplated materials comprising the housing  110  include plastic, and possibly hard rubber. In preferred embodiments, the housing  110  is sized and dimensioned to create a desired shape to fit narrow or wide diameter pencils.  
         [0020]     Cutter  120  is contemplated to comprise any durable, rust-proof material, including stainless steel, aluminum, metal alloy, or hard plastic material or polymer. Positioning of the cutter  120  likely affects the sharpness/bluntness of the soft center after sharpening. The cutter  120  is typically positioned at least 45 degrees from the normal angle to create a very sharp tip, and less than 20 degrees from the normal angle to create a blunt tip. It is contemplated that the cutter is positioned so as to minimize jamming of the soft center of a pencil  20 .  
         [0021]     Cap  10  has a retention mechanism that removably couples the cap  10  to a corresponding pencil  20 .  FIG. 1  depicts a retention mechanism that is a snap fit mechanism, with a retention ring  130  placed near the open end of the cap  10  to provide a gripping and retention mechanism between the cap  10  and the corresponding pencil  20 . The retention ring  130  works in a fashion similar to that of many common plastic pens and their corresponding caps. Other contemplated retention mechanisms include friction or compression collar mechanisms  135 , as depicted in  FIG. 3 . When a friction or compression collar mechanism is used, the cap  10  is pressed onto the pencil  20  until the cap  10  is relatively securely in place.  
         [0022]     Further contemplated embodiments include kits comprising a pencil  20  and a corresponding pencil sharpener cap  10  that are sized and dimensioned so that when the cap covers the pencil, the length of the cap  10  together with the pencil  20  remain approximately a constant size as the pencil is used and sharpened. This is depicted in  FIGS. 1 and 2 . Thus, when the pencil  20  is full-length, a larger portion of the pencil  20  will fit inside the cap  10 , and as the pencil  20  becomes smaller, less of the pencil  20  fits inside the cap  10 . The cap  10  preferably has a length at least 50% or even 75% that of the length of the corresponding pencil  20 . Viewed from another perspective, when a full-length pencil  20  is stored within the cap  10 , the lumen of the cap  10  may receive at least 50%, or 75% that of the length of the pencil  20 .  
         [0023]     In  FIG. 2 , biased flaps  150  are used in the pencil sharpener cap  10  to prevent shavings or lead from the cutter  220  or the reservoir  300  from falling out. The biased flaps  150  are preferably positioned near or on the sharpener  100  so that when a pencil  20  is inserted into the housing, the biased flaps  150  open to allow insertion of the pencil  20 . Furthermore, when the pencil  20  is pulled out, the biased flaps  150  remain in a closed position, which tends to prevent shavings and other debris from falling out. It is especially preferred that the biased flaps  150  are positioned on the sharpener at a point near where the pencil  20  is inserted into the sharpener  100  so as to catch and prevent all the shavings and other debris from falling out of the cap.  
         [0024]     The shavings reservoir  200  is the space between the closed end of the cap  10  and the sharpener  100 . The shavings reservoir  200  is capable of holding at least some of the shavings from the corresponding pencil  20 . In preferred embodiments, the shavings reservoir  200  holds all the shavings from a corresponding pencil  20 . Thus, the shavings reservoir  200  may be sized and dimensioned to hold a volume of between 15 and 100 cc, and more preferably between 30 and 60 cc. The key is that the maximum size of the shavings reservoir  200  should be capable of holding all the shavings from one pencil  20 .  
         [0025]     It is further contemplated that at least one of the interior wall, exterior wall, and sharpener  100  is moved in order to increase or decrease the size of the shavings reservoir  200 . The internal wall may comprise a portion of the sharpener  100 . The external wall may be telescopically coupled to the sharpener  100 . The mechanism through which the shavings reservoir  200  moves is discussed in detail below.  
         [0026]     The cap  10  is probably injection molded and most likely has a substantially uniform wall thickness so that the shape of the reservoir  200  is likely approximately the same shape as the outer portion of the cap  10 . The outer portion of the cap  10  may comprise any suitable shape including substantially tubular, substantially rectangular, or any other shape that is easy to handle and transport such as in a purse, pocket, or briefcase. In preferred embodiments, the cap  10  is substantially tubular with a tapered end.  
         [0027]     A notch-type mechanism may be used to move the shavings reservoir  200 . A notch-type mechanism functions in a manner that allows one to manually slide the sharpener  100  away from the opening of the cap  10  to decrease the size of the shavings reservoir  200  or down the cap  10  to increase the size of the shavings reservoir  200 .  FIGS. 1 and 3  depict a notch-type mechanism where a tab  160  is coupled to the sharpener  100  and extends to the periphery of the cap  10  to allow one to manually slide the notch up and down the cap  10  in order to move the sharpener  100 .  
         [0028]     In  FIG. 2 , the retention mechanism  300  is a screw type mechanism. The sharpener  100  is typically placed on grooves so that the sharpener is carried along the screws to increase or decrease the size of the shavings reservoir  200 . The screws can be turned by any known mechanism, including a dial, rotary actuator  170 , or other type of handle.  FIG. 2  depicts a rotary actuator located at the tapered end of the cap  10 . Another less preferred embodiment includes coupling the rotation of the pencil during sharpening to the movement of the sharpener so that as the pencil is sharpened, the sharpener moves toward the open end of the cap. The twisting of the sharpener  100  may or may not be coupled to the twisting of the pencil  20  during sharpening. Thus, specific embodiments and applications have been disclosed of pencil sharpener caps. It should be apparent, however, to those skilled in the art that many more modifications besides those already described are possible without departing from the inventive concepts herein. The inventive subject matter, therefore, is not to be restricted except in the spirit of the appended claims. Moreover, in interpreting both the specification and the claims, all terms should be interpreted in the broadest possible manner consistent with the context. In particular, the terms “comprises” and “comprising” should be interpreted as referring to elements, components, or steps in a non-exclusive manner, indicating that the referenced elements, components, or steps may be present, or utilized, or combined with other elements, components, or steps that are not expressly referenced.