Patent Publication Number: US-10315317-B2

Title: Blade cartridges and lockable safety covers

Description:
FIELD OF THE INVENTION 
     The field of the invention is utility knives. 
     BACKGROUND 
     The background description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art. 
     Safety has been an important concern when using utility knives as many users inadvertently cut themselves with the exposed blades. Some efforts have been made to address this safety concern. 
     For example, U.S. Pat. No. 8,347,509 teaches a blade cartridge with a blade cover that defaults to a closed position in which the blade cover surrounds the otherwise exposed portion of a blade. A spring is used to push the blade cover into the closed position, and the blade cover remains in the closed position until pressure is applied to push the cover to an open configuration where the blade is exposed for use. 
     This and all other publications referenced herein are incorporated by reference to the same extent as if each individual publication or patent application were specifically and individually indicated to be incorporated by reference. Where a definition or use of a term in an incorporated reference is inconsistent or contrary to the definition of that term provided herein, the definition of that term provided herein applies and the definition of that term in the reference does not apply. 
     Unfortunately, the &#39;509 Patent&#39;s blade cartridge and blade cover fails to address several other safety issues, for example, injuries that can occur from an inadvertent detaching of the cartridge or blade from a tool handle. 
     U.S. Pat. Nos. 7,475,480 and 8,099,868 each strive to solve this problem by featuring a flexing latch to secure the handle to the cartridge. While the cartridge is inserted into the handle, the latches flex into a strained position in order to fit into the receiving channel of the handle. Once the cartridge has been fully inserted into the handle, the latches then return to a relaxed, unstrained position by pushing through openings on either side of the handle. Such a latching mechanism is useful in securing the blade. 
     Unfortunately, the cartridge is at risk of inadvertent detachment from the handle because the latches are positioned on the handle at a place where users commonly squeeze their thumb and first finger together to grip and manipulate the tool. 
     Thus, there is still a need for improved and safer utility knives and utility knife components. 
     SUMMARY OF THE INVENTION 
     The following description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art. 
     The inventive subject matter provides apparatus, systems, and methods in which a utility knife includes a blade cover that is movable from a locked position to an unlocked position relative to at least one of a blade cartridge, a blade holder, and a tool handle. When the blade cover is in an unlocked position, the blade cover can advantageously be moved (e.g., rotate (partially or fully), pivot, slide, swivel, turn, bend, flex) from a blade covering configuration to a blade exposing configuration. 
     The blade cover could be biased towards the blade covering configuration, for example, via a spring, such that a force (e.g., from a cutting surface or a user) is required to move to the blade exposing configuration. 
     In some aspects, contemplated utility knives could comprise a cartridge that is coupled to or includes a blade, and a blade cover coupled to the cartridge. The cartridge could comprise a stem that extends from an end of the cartridge opposite the blade. The stem could include one or more flexible spring arms that each includes a locking member sized and dimensioned to be releasably received by a catch of a tool handle. Advantageously, the spring arms could be configured to flex in opposite directions and towards one another such that the cartridge could readily be removed from the tool handle when desired. Additionally or alternatively, the catches that receive the locking mechanisms could be positioned on top and bottom portions of the tool handle (when the tool is being used), such that unintentional release of the cartridge from the handle during use can be avoided. 
     Various objects, features, aspects and advantages of the inventive subject matter will become more apparent from the following detailed description of preferred embodiments, along with the accompanying drawing figures in which like numerals represent like components. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWING 
         FIG. 1A  illustrates a blade cartridge and cover of the inventive subject matter, wherein the cover is in a locked position. 
         FIG. 1B  illustrates the blade cartridge and cover of  FIG. 1A , wherein the cover is in an unlocked position. 
         FIG. 1C  illustrates the blade cartridge and cover of  FIGS. 1A-1B , wherein the cover is in a blade exposing configuration. 
         FIG. 2A  illustrates another blade cartridge and cover of the inventive subject matter, wherein the cover is in an unlocked position and a blade covering configuration. 
         FIG. 2B  illustrates the blade cartridge and cover of  FIG. 2A , wherein the cover is in an unlocked position and a blade exposing configuration. 
         FIG. 3  illustrates a utility knife of the inventive subject matter. 
         FIG. 4  illustrates another utility knife of the inventive subject matter. 
     
    
    
     DETAILED DESCRIPTION 
     The inventive subject matter provides utility knives with a safety cover that is movable from a locked position to an unlocked position (and vice versa), and from a biased unexposed blade configuration to an exposed blade configuration (and vice versa). The utility knives can include a cartridge for a blade and blade cover, and a tool handle that is configured to securely and releasably receive the cartridge. 
     The following discussion provides many example embodiments of the inventive subject matter. Although each embodiment represents a single combination of inventive elements, the inventive subject matter is considered to include all possible combinations of the disclosed elements. Thus if one embodiment comprises elements A, B, and C, and a second embodiment comprises elements B and D, then the inventive subject matter is also considered to include other remaining combinations of A, B, C, or D, even if not explicitly disclosed. 
       FIGS. 1A-1C  illustrate a utility knife cartridge  100  of the inventive subject matter. Cartridge  100  comprises blade holder or blade holder component  110 , blade  65 , stem  90 , and blade cover  30 . Blade holder  110  and stem  90  could be made from a single piece of material (e.g., injected molded plastic, metal). In other contemplated embodiments, blade holder  110  and stem  90  could be made from separate pieces of material. 
     Where a separate tool handle is not used with a cartridge of the inventive subject matter, stem  90  could be replaced with or otherwise include a handle. Here, cartridge  100  is one of many cartridges that can be used in combination with a tool handle (e.g.,  350  of  FIG. 3 ). In order to allow cartridge  100  to be releasably coupled to the tool handle, stem  90  includes a first arm  40  with a first stem locking member  40 A, and a second arm  45  with a second locking member  45 A. Each locking member is configured to mate with a catch of a tool handle as further described below. 
     Blade cover  30  is advantageously configured to move (e.g., slide) relative to the blade holder from a locked position, as shown in  FIG. 1A , to an unlocked position, as shown in  FIG. 1B . Blade holder  110  comprises a lock protrusion  50  that is configured to cooperate with blade cover&#39;s lock opening  55 . This allows the blade cover  30  to be locked in a safe position that keeps the blade from being inadvertently exposed, regardless of whether or not the cartridge has been inserted into a tool handle. 
     Additionally, blade cover  30  is configured to move (e.g., rotate) relative to the blade holder and blade from a blade covering configuration, as shown in  FIG. 1B , to a blade exposing configuration, as shown in  FIG. 1C . Blade holder  110  comprises a movement protrusion  70  that is configured to cooperate with blade cover&#39;s angled channel  105  to allow for rotation of blade cover  30  when it is in an unlocked position. 
     Here, lock opening  55  and angled channel  105  are shown as extending through a thickness of blade cover  30 . However, it should be appreciated that lock protrusion  50  and movement protrusion  70  could additionally or alternatively cooperate with recessed portions or grooves on an inner surface of blade cover  30 . 
     Still further, while blade holder  110  is shown to have the lock and movement protrusions, and blade cover  30  is shown to have the lock opening and angled channel, it should be appreciated that one or more of the protrusions could be included on the blade cover, and one or more of the openings or channels could be included on the blade holder. 
     In the embodiment shown, lock opening  55  is peanut shaped, and includes a narrow central portion between two wider ends. Lock protrusion  50  can be positioned, sized and dimensioned to snugly fit through the narrow central portion when a force towards one of the wider ends is applied by a user. Viewed from another perspective, a user could use at least one of a thumb and forefinger to hold the blade cover and move it towards the stem  90  to unlock the blade cover. Additionally or alternatively, the user could move the blade cover towards the blade  65  to lock the blade cover. 
     One or more slots (e.g.,  60 ) could be included on blade cover  30  to allow the central portion of lock opening  55  to widen and allow lock protrusion  50  to pass through. Additionally or alternatively, one or more slots could be included on blade cover that allows a user to see blade  65  (or other tool) when blade cover is in a blade covering configuration. 
     In some embodiments, the lock protrusion  50  could have a varying thickness, and include at least one thinner portion and at least one wider portion. The wider portion(s) could be wider than the narrow central portion of lock opening  55 , and thus not sized and dimensioned to pass through the narrow central portion. The thinner portion(s) could be positioned further away from blade holder  110  than the wider portion, such that lock protrusion  50  could be pushed in, and the thinner portion could pass through the narrow central portion of lock opening  55 . Additionally or alternatively, the thinner portion could be positioned closer to the blade holder such that the lock protrusion could be pulled out, and the thinner portion could pass through the narrow central portion. 
     When the blade cover is moved from a locked position (as shown in  FIG. 1A ) to an unlocked position (as shown in  FIG. 1B ), movement protrusion  70  could be positioned at a corner of channel  105  such that blade cover  30  can move from a blade covering configuration (as shown in  FIG. 1B ) to a blade exposing configuration (as shown in  FIG. 1C ). As illustrated in  FIGS. 1A-1C , the channel  105  can include a first sub-channel and a second sub-channel. The movement protrusion  70  could move through first sub-channel when blade cover  30  moves between a locked position and an unlocked configuration. The movement protrusion  70  could move through the second curved sub-channel when blade cover  30  moves between a blade covering configuration and a blade exposing configuration. 
     In some embodiments, blade cover  30  could be biased towards the blade covering configuration (e.g., via a spring). An exemplary spring biasing mechanism is the curved spring carried in a groove and described in U.S. Pat. No. 8,099,868 to Votolato. When blade cover  30  is in an unlocked position, a user could apply a pressure to a portion of the blade cover, for example, via a cutting surface, and cause the blade to be exposed to apply a cut to the cutting surface (item to be cut). When the pressure is released (e.g., when the knife is moved away from a cutting surface), blade cover  30  could automatically move back to a blade covering configuration. 
     It should be appreciated that the locking feature (lock opening  55  and lock protrusion  50 ) can allow a user to repeatedly lock and unlock the cover with a simple movement. A user can simply grab the blade cover with a forefinger and thumb, and pull or push the blade cover slightly away from or towards the knife handle. This can prevent accidental exposure to the cartridge blade when the knife is not in use (e.g., when it is in a pocket of a user, is placed in a toolbox or left unattended, when the cartridge is being coupled to, or removed from, a tool holder. 
     It is contemplated that cartridge  100  could be replaced with another blade cartridge, for example, when blade  65  becomes dull. Additionally or alternatively, cartridge  100  could be replaced with a different tool cartridge (e.g., screw driver cartridge, saw cartridge, scraper cartridge). The different tool cartridges could be the same as utility knife cartridge  100 , except that blade  65  is replaced with a different tool. 
       FIGS. 2A-2B  illustrate another utility knife cartridge  200  of the inventive subject matter. Cartridge  200  includes blade holder  235  having a stem, blade  230 , and a partially transparent blade cover  210 . Cartridge  200  includes a lock opening and lock protrusion similar to those described in  FIGS. 1A-1C . Cartridge  200  also includes slots  220 A and  220 B that provide some flexibility to blade cover  210 . Furthermore, cartridge  200  includes a movement protrusion  240  that cooperates with channel  215  to allow blade cover  210  to adjust between locked and unlocked positions, and between blade covering (closed) and blade exposing (open) configurations. 
     In some embodiments, a cartridge blade cover could default/be biased to a closed position in which the blade cover surrounds the otherwise exposed portion of a blade. A spring (e.g., a curved spring) could be included, which pushes the blade cover into the closed position. The blade cover could remain in the closed position until pressure is applied to push the cover to an open configuration where the blade is exposed for use. 
     Additionally or alternatively to a spring, cartridge  200  could include an elongated piece  245  that can bias the blade cover in the closed position. When blade cover  210  is moved to an open configuration by a cutting surface or other force, blade cover  210  can cause elongated piece  245  to flex to a strained position within open region  225  (as shown in  FIG. 2B ). 
     As discussed above, cartridges of the inventive subject matter could include stems that are configured to be releasably received by one or more tool handles of the inventive subject matter.  FIG. 3  illustrates a utility knife  300 , which includes a cartridge  310  releasably locked into place on tool handle  350 . 
     Cartridge  310  includes a blade holder, blade  320 , blade cover  315 , and a stem that includes two flexible arms that include two locking members ( 325 ,  330 ). In one embodiment, the stem and flexible arms are configured such that considerable pressure is required to depress the two flexible arms. In another embodiment, only slight pressure is required to depress the two flexible arms. Further, in some embodiments, after pressure is released from the two flexible arms, the arms return back to their original positions. In a further embodiment, only when the two flexible arms are depressed is cartridge  310  able to fit into tool handle  350 , while in another only one flexible arm must be depressed. 
     Tool handle  350  includes a first catch  355  sized and dimensioned to receive a first locking member (e.g.,  40 A,  325 ), and a second catch  360  sized and dimensioned to receive a second locking member (e.g.,  45 A,  330 ). In the embodiment shown, catch  355  is located on a bottom edge of knife  300 , and catch  360  is located on a top edge of knife  300 . When cartridge  310  is locked with tool handle  350 , the two flexible arms can be flexed towards each other (away from their resting positions) to allow locking members  325  and  330  to snap into catches  355  and  360 , respectively. From another perspective, the flexible arms of cartridge  310  could be configured such that, in a relaxed position, locking members  325  and  330  rest snugly and securely within catches  355  and  360 . 
     The receiving end of the opening of the tool holder can be sized and dimensioned to receive the arms of cartridge  310  in a way that momentarily depresses those arms, allowing for locking members  325  and  330  to slide into the tool handle opening, and then to snap back to lock into place in catches  355  and  365  located on the vertical plane or spine of the handle. 
     When removing cartridge  310  for replacement, a user can simply squeeze or pinch the stem arms together via locking members  325  and  330 , allowing cartridge  310  to be pulled out from tool handle  350 . In some embodiments, the force required to depress the stem arms is great, while in others slight pressure is sufficient. 
     Cartridge  310  can further be configured such that, while inserting cartridge  310  into tool handle  350 , cartridge  310  is shifted into a locked configuration where blade cover  315  cannot move in relation to blade  320 . This can be accomplished, for example, by reversing the orientation of angled channel  105  such that a pushing motion along blade cover  315  toward tool handle  350  slides the lock protrusion along the angled channel into a locked conformation. 
     Cartridge  310  can further be configured such that, while removing cartridge  310  from tool handle  350 , cartridge  310  is shifted into a locked configuration where blade cover  315  cannot move in relation to blade  320 . This can be accomplished, for example, by using the orientation of angled channel  105  such that a pulling motion along blade cover  315  away from tool handle  350  slides the lock protrusion along the angled channel into a locked conformation. 
     Whereas known utility knives included spring arms protruding along the horizontal axis and perpendicular to the orientation of the blade, cartridges of the inventive subject matter can advantageously include flexible arms on the vertical plane, and in the same direction as the orientation of the blade. Viewed from another perspective, when knife  300  is used to make a cut, a user can grab left and right sides of the blade without inadvertently releasing the cartridge from the tool handle. 
       FIG. 4  illustrates another utility knife  400  of the inventive subject matter. Knife  400  includes stem  455  and cartridge  450 . Cartridge  450  includes a blade holder, blade, blade cover  410 , and two flexible arms including locking members  435  and  440 . Stem  455  includes first and second catches  460  and  465 , which are sized and dimensioned to block locking members  435  and  440  in place. 
     Cartridge  450  is similar to the cartridges shown in  FIGS. 1A-1C  and  FIGS. 2A-2B , and includes mechanisms that allow blade cover  410  to move between locked and unlocked positions, and between closed and open configurations. As illustrated, blade cover  410  is in a locked position. A user could use his thumb and forefinger, a cutting surface, or any other suitable force to move blade cover  410  towards stem  455  such that locking protrusion  415  moves to an opposite end of lock opening  420  (unlocked position). This would position moving protrusion  430  within the corner of angled channel  425 , and allow a user to rotate blade cover  410  to a blade exposing (open) configuration. Some contemplated channels allow blade cover  410  to rotate between 25-75 degrees, more preferably between 25-65 degrees, and even more preferably between 25-55 degrees. 
     Methods of making cartridges as described are also contemplated. A cartridge as detailed in  FIGS. 1A-4  can be assembled by fixing a blade to a cartridge. The blade can be made of metal, plastic, ceramic, wood, bone, keratin, enamel, carbon, stone, obsidian, glass, diamond, or any other material suitable for cutting or applying directed pressure. Further, the blade may be straight, curved, round, angled, serrated, sharpened, dulled, or otherwise configured as appropriate for the desired use. The cartridge may be a single piece or the composite of several pieces. The pieces could be of the same material (e.g., injection molded plastic) or of a range of materials. 
     A cartridge as described above can be made by fixing a blade cover to the blade holder. The blade cover can be an integral part of the blade holder and can be made of the same material as the blade holder. For example, the blade cover and blade holder can be made of a single piece of flexible rubber. Further, the blade cover and blade holder can be made primarily of the same material as an integral piece, while the blade holder is further comprised of other components or materials. The blade cover and the blade holder can also be separate components, and can be made of different materials or the same material. The blade cover can be fixed to the blade holder by means that permit the blade cover to rotate (partially or fully), pivot, slide, swivel, turn, bend, flex or otherwise move in relation to the blade. 
     A cartridge as described above can also be made such that the blade cover and the blade holder are attached at a junction. The junction can be further configured such that a part of the junction prevents or allows the blade cover to move in relation to the blade, while another part of the junction provides the avenue or means for the blade cover to move in relation to the blade. The means of preventing or allowing movement, and restricting the direction of movement, of the blade cover in relation to the blade can be an integral part of the junction between the blade cover and the cartridge, or can be a separate component. Further, the components can be made of the same or different materials. 
     A cartridge as described above can further be made by fixing flexible arms to the blade holder. The flexible arms can be a separate component from the blade holder or can be an integral aspect of the blade holder. The flexible arms and blade holder can be made of the same material or of different materials. The flexible arms can be configured such that they depress while being inserted into a tool handle, and then return to an undepressed position once completely inserted into the tool handle. 
     As used in the description herein and throughout the claims that follow, the meaning of “a,” “an,” and “the” includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein, the meaning of “in” includes “in” and “on” unless the context clearly dictates otherwise. 
     As used herein, and unless the context dictates otherwise, the term “coupled to” is intended to include both direct coupling (in which two elements that are coupled to each other contact each other) and indirect coupling (in which at least one additional element is located between the two elements). Therefore, the terms “coupled to” and “coupled with” are used synonymously. 
     The recitation of ranges of values herein is merely intended to serve as a shorthand method of referring individually to each separate value falling within the range. Unless otherwise indicated herein, each individual value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g. “such as”) provided with respect to certain embodiments herein is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention otherwise claimed. No language in the specification should be construed as indicating any non-claimed element essential to the practice of the invention. 
     Groupings of alternative elements or embodiments of the invention disclosed herein are not to be construed as limitations. Each group member can be referred to and claimed individually or in any combination with other members of the group or other elements found herein. One or more members of a group can be included in, or deleted from, a group for reasons of convenience and/or patentability. When any such inclusion or deletion occurs, the specification is herein deemed to contain the group as modified thus fulfilling the written description of all Markush groups used in the appended claims. 
     It should be apparent 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 scope 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. Where the specification claims refers to at least one of something selected from the group consisting of A, B, C . . . and N, the text should be interpreted as requiring only one element from the group, not A plus N, or B plus N, etc.