Blade cartridges and lockable safety covers

Apparatuses, 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 are provided. When the blade cover is in an unlocked position, the blade cover can advantageously be moved from a blade covering configuration to a blade exposing configuration.

FIELD OF THE INVENTION

The field of the invention is utility knives.

BACKGROUND

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.

Unfortunately, the '509 Patent'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 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.

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.

FIGS. 1A-1Cillustrate a utility knife cartridge100of the inventive subject matter. Cartridge100comprises blade holder or blade holder component110, blade65, stem90, and blade cover30. Blade holder110and stem90could be made from a single piece of material (e.g., injected molded plastic, metal). In other contemplated embodiments, blade holder110and stem90could be made from separate pieces of material.

Where a separate tool handle is not used with a cartridge of the inventive subject matter, stem90could be replaced with or otherwise include a handle. Here, cartridge100is one of many cartridges that can be used in combination with a tool handle (e.g.,350ofFIG. 3). In order to allow cartridge100to be releasably coupled to the tool handle, stem90includes a first arm40with a first stem locking member40A, and a second arm45with a second locking member45A. Each locking member is configured to mate with a catch of a tool handle as further described below.

Blade cover30is advantageously configured to move (e.g., slide) relative to the blade holder from a locked position, as shown inFIG. 1A, to an unlocked position, as shown inFIG. 1B. Blade holder110comprises a lock protrusion50that is configured to cooperate with blade cover's lock opening55. This allows the blade cover30to 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 cover30is configured to move (e.g., rotate) relative to the blade holder and blade from a blade covering configuration, as shown inFIG. 1B, to a blade exposing configuration, as shown inFIG. 1C. Blade holder110comprises a movement protrusion70that is configured to cooperate with blade cover's angled channel105to allow for rotation of blade cover30when it is in an unlocked position.

Here, lock opening55and angled channel105are shown as extending through a thickness of blade cover30. However, it should be appreciated that lock protrusion50and movement protrusion70could additionally or alternatively cooperate with recessed portions or grooves on an inner surface of blade cover30.

Still further, while blade holder110is shown to have the lock and movement protrusions, and blade cover30is 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 opening55is peanut shaped, and includes a narrow central portion between two wider ends. Lock protrusion50can 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 stem90to unlock the blade cover. Additionally or alternatively, the user could move the blade cover towards the blade65to lock the blade cover.

One or more slots (e.g.,60) could be included on blade cover30to allow the central portion of lock opening55to widen and allow lock protrusion50to pass through. Additionally or alternatively, one or more slots could be included on blade cover that allows a user to see blade65(or other tool) when blade cover is in a blade covering configuration.

In some embodiments, the lock protrusion50could 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 opening55, and thus not sized and dimensioned to pass through the narrow central portion. The thinner portion(s) could be positioned further away from blade holder110than the wider portion, such that lock protrusion50could be pushed in, and the thinner portion could pass through the narrow central portion of lock opening55. 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 inFIG. 1A) to an unlocked position (as shown inFIG. 1B), movement protrusion70could be positioned at a corner of channel105such that blade cover30can move from a blade covering configuration (as shown inFIG. 1B) to a blade exposing configuration (as shown inFIG. 1C). As illustrated inFIGS. 1A-1C, the channel105can include a first sub-channel and a second sub-channel. The movement protrusion70could move through first sub-channel when blade cover30moves between a locked position and an unlocked configuration. The movement protrusion70could move through the second curved sub-channel when blade cover30moves between a blade covering configuration and a blade exposing configuration.

In some embodiments, blade cover30could 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 cover30is 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 cover30could automatically move back to a blade covering configuration.

It should be appreciated that the locking feature (lock opening55and lock protrusion50) 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 cartridge100could be replaced with another blade cartridge, for example, when blade65becomes dull. Additionally or alternatively, cartridge100could 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 cartridge100, except that blade65is replaced with a different tool.

FIGS. 2A-2Billustrate another utility knife cartridge200of the inventive subject matter. Cartridge200includes blade holder235having a stem, blade230, and a partially transparent blade cover210. Cartridge200includes a lock opening and lock protrusion similar to those described inFIGS. 1A-1C. Cartridge200also includes slots220A and220B that provide some flexibility to blade cover210. Furthermore, cartridge200includes a movement protrusion240that cooperates with channel215to allow blade cover210to 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, cartridge200could include an elongated piece245that can bias the blade cover in the closed position. When blade cover210is moved to an open configuration by a cutting surface or other force, blade cover210can cause elongated piece245to flex to a strained position within open region225(as shown inFIG. 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. 3illustrates a utility knife300, which includes a cartridge310releasably locked into place on tool handle350.

Cartridge310includes a blade holder, blade320, blade cover315, 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 cartridge310able to fit into tool handle350, while in another only one flexible arm must be depressed.

Tool handle350includes a first catch355sized and dimensioned to receive a first locking member (e.g.,40A,325), and a second catch360sized and dimensioned to receive a second locking member (e.g.,45A,330). In the embodiment shown, catch355is located on a bottom edge of knife300, and catch360is located on a top edge of knife300. When cartridge310is locked with tool handle350, the two flexible arms can be flexed towards each other (away from their resting positions) to allow locking members325and330to snap into catches355and360, respectively. From another perspective, the flexible arms of cartridge310could be configured such that, in a relaxed position, locking members325and330rest snugly and securely within catches355and360.

The receiving end of the opening of the tool holder can be sized and dimensioned to receive the arms of cartridge310in a way that momentarily depresses those arms, allowing for locking members325and330to slide into the tool handle opening, and then to snap back to lock into place in catches355and365located on the vertical plane or spine of the handle.

When removing cartridge310for replacement, a user can simply squeeze or pinch the stem arms together via locking members325and330, allowing cartridge310to be pulled out from tool handle350. In some embodiments, the force required to depress the stem arms is great, while in others slight pressure is sufficient.

Cartridge310can further be configured such that, while inserting cartridge310into tool handle350, cartridge310is shifted into a locked configuration where blade cover315cannot move in relation to blade320. This can be accomplished, for example, by reversing the orientation of angled channel105such that a pushing motion along blade cover315toward tool handle350slides the lock protrusion along the angled channel into a locked conformation.

Cartridge310can further be configured such that, while removing cartridge310from tool handle350, cartridge310is shifted into a locked configuration where blade cover315cannot move in relation to blade320. This can be accomplished, for example, by using the orientation of angled channel105such that a pulling motion along blade cover315away from tool handle350slides 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 knife300is 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. 4illustrates another utility knife400of the inventive subject matter. Knife400includes stem455and cartridge450. Cartridge450includes a blade holder, blade, blade cover410, and two flexible arms including locking members435and440. Stem455includes first and second catches460and465, which are sized and dimensioned to block locking members435and440in place.

Cartridge450is similar to the cartridges shown inFIGS. 1A-1CandFIGS. 2A-2B, and includes mechanisms that allow blade cover410to move between locked and unlocked positions, and between closed and open configurations. As illustrated, blade cover410is in a locked position. A user could use his thumb and forefinger, a cutting surface, or any other suitable force to move blade cover410towards stem455such that locking protrusion415moves to an opposite end of lock opening420(unlocked position). This would position moving protrusion430within the corner of angled channel425, and allow a user to rotate blade cover410to a blade exposing (open) configuration. Some contemplated channels allow blade cover410to 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 inFIGS. 1A-4can 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.