Patent Description:
Frame lock folding knives typically include an over-rotation inhibiting disc that is coupled to a handle, which inhibits the over rotation of a locking mechanism. However, over-rotation inhibiting discs do not inhibit a user from inadvertently actuating the locking mechanism while opening or closing the knife. This can lead to reduced user satisfaction. <CIT> discloses a folding knife that can include a handle portion, a pivot element, a blade, a locking element, a cap, and a rotatable wheel. The handle portion can comprise a first side portion and a second side portion. The blade can pivot about the pivot element between an open position and a closed position. The locking element can prevent disassembly of the first and second side portions when the locking element is in a locked position and allow disassembly of the first and second side portions when the locking element is in an unlocked position. The cap can be coupled to the first side portion adjacent the locking element. The pivot element can extend into the cap. The rotatable wheel can be disposed between the first and second side portions and can rotated to selectively retain the first and second side portions together.

One embodiment relates to a knife that includes a blade and a handle assembly rotatably coupled to the blade. The handle assembly includes a side frame, a locking arm coupled to the side frame and movable between a locked position and an unlocked position and a guard. The locking arm defines an arm length. The guard is coupled to the side frame and overlays at least a portion of the locking arm. The guard defines a guard length in a direction parallel to the arm length, and a ratio of the guard length to the arm length is between about seventy-five percent (<NUM>%) to about one hundred percent (<NUM>%).

Another embodiment relates to a knife that includes a blade, and a handle assembly rotatably coupled to the blade and defining a longitudinal axis. The handle assembly includes a side frame, a locking arm coupled to the side frame and movable between a locked position and an unlocked position, and a guard. The locking arm defines an arm width in a direction perpendicular to the longitudinal axis. The guard is coupled to the side frame and overlays at least a portion of the locking arm. The guard defines a guard width in a direction perpendicular to the longitudinal axis, and a ratio of the guard width to the arm width at any given position along the longitudinal axis is between about thirty percent (<NUM>%) and about one hundred percent (<NUM>%).

Another embodiment relates to a knife that includes a blade, and a handle assembly rotatably coupled to the blade and defining a longitudinal axis. The handle assembly includes a handle frame, a side frame coupled to the handle frame, and a locking arm coupled to the side frame by a living hinge and movable between a locked position and an unlocked position. The living hinge biases the locking arm toward the locked position. The locking arm defines an arm width in a direction perpendicular to the longitudinal axis and an arm length in a direction parallel to the longitudinal axis. A guard is coupled to the side frame and overlays at least a portion of the locking arm. The guard defines a guard width in a direction perpendicular to the longitudinal axis and a guard length in a direction parallel to the longitudinal axis. A ratio of the guard width to the arm width at any given position along the longitudinal axis is greater than thirty percent (<NUM> %), and a ratio of the guard length to the arm length is between about seventy-five percent (<NUM>%) to about one hundred percent (<NUM>%).

Alternative exemplary embodiments relate to other features and combinations of features as may be generally recited in the claims.

Referring generally to the drawings, a folding knife is shown and described that includes a blade pivotably coupled to a handle assembly and movable between a deployed, or "use" position and a stowed, or "storage" position. The handle assembly includes a side frame, a liner, and a handle frame. A locking arm is connected to the side frame by a living hinge. The locking arm is structured to move between a locked position and an unlocked position and is biased toward the locked position by the living hinge. A lock guard is connected to the side frame and partially covers the locking arm. The lock guard is positioned to inhibit a user from actuating or pressing on the locking arm while moving the blade between the use position and the storage position.

Referring to <FIG>, a knife <NUM> includes a blade <NUM> that is rotatably coupled to a handle assembly <NUM>. In some examples, the blade <NUM> is secured to the handle assembly <NUM> using an axle, shown as pivot pin <NUM>. The blade <NUM> is configured to rotate about the pivot pin <NUM> between a stowed position (shown in <FIG>) and a deployed position (shown in <FIG>). The blade <NUM> can be formed of a hardened or otherwise rigid material, and is adapted for cutting, chopping, and/or slicing objects. The blade <NUM> can include an opening feature, shown as an opening aperture <NUM>, along with a cutting edge <NUM> and a finger choil <NUM>. The opening aperture <NUM> can be formed through the top section of the blade <NUM>, for example, and serves as a gripping feature to help a user grab and control the blade <NUM>. For example, the opening aperture <NUM> can be sized to receive a portion of the user's thumb for actuating the blade <NUM> between a deployed position and a storage position. The shape and location of the opening aperture <NUM> can also be varied to accommodate different blade shapes and sizes. Although shown as a negative feature (i.e., a recess or aperture), positive shapes and/or protrusions can also be incorporated into or otherwise coupled to the blade <NUM> to serve as an opening feature. For example, the opening feature can instead be an opening stud or cylindrical protrusion (not shown).

The handle assembly <NUM> includes a handle frame <NUM>. The handle frame <NUM> is shaped to receive at least a portion of the blade <NUM>, and can be further contoured to provide ergonomic comfort to the user while using and/or grasping the knife <NUM>. As shown in <FIG>, the handle assembly <NUM> includes a side frame <NUM> positioned on an opposite side of the knife <NUM> from the handle frame <NUM>. The side frame <NUM> and handle frame <NUM> are spaced apart from one another and extend approximately parallel to one another along the length of the knife <NUM>. The side frame <NUM> and handle frame <NUM> together define a cavity <NUM> that is configured to receive a portion of the blade <NUM>, including the cutting edge <NUM>, when the blade <NUM> is in the storage position.

The side frame <NUM> includes a locking arm <NUM> connected to the side frame <NUM> by a living hinge <NUM>. The locking arm <NUM> prevents unwanted rotation of the blade <NUM> from the deployed position into the storage position by blocking the rotation of the blade <NUM> relative to the handle assembly <NUM>. The locking arm <NUM> is actuatable between a locked position (shown in <FIG>) and an unlocked position (shown in <FIG>). The living hinge <NUM> biases the locking arm <NUM> inward, toward the locked position. The inward bias of the locking arm <NUM> causes the locking arm <NUM> to engage the blade <NUM> in the storage position, creating interference and friction that resists unwanted rotation of the blade <NUM> away from the handle assembly <NUM>. Pulling on the blade <NUM> (e.g., by grabbing the opening aperture <NUM>) can overcome the inward bias of the locking arm <NUM>. As the blade <NUM> rotates, contact between the blade <NUM> and locking arm <NUM> flexes the locking arm <NUM> outward, toward the unlocked position, which allows the blade <NUM> to rotate. Once the blade <NUM> has rotated beyond the locking arm <NUM>, the natural bias of the living hinge <NUM> returns the locking arm <NUM> to the inward, locked position, where the locking arm <NUM> engages a tang <NUM> of the blade <NUM> and resists rotation of the blade <NUM> relative to the handle assembly <NUM>.

The handle assembly <NUM> can also include mounting features that allow a user to readily access and stow the knife. For example, a pocket clip <NUM> can be fastened to the side frame <NUM>. The pocket clip <NUM> is sized to engage a pocket of the user's pants to hold the knife <NUM> in place. The pocket clip <NUM> can be secured to the handle assembly <NUM> using screws or other fasteners, which are anchored to the side frame <NUM>. The side frame <NUM> and handle frame <NUM> can be formed of various materials, including metallic materials (e.g., aluminum), polymeric materials (e.g., G10 nylon), composite materials (e.g., carbon fiber), or some combination of these materials.

In addition to the locking arm <NUM> and pocket clip <NUM>, the side frame <NUM> also defines a guard recess <NUM>. The guard recess <NUM> can extend into the side frame <NUM>, and can have a generally concave shape that is sized to receive a frame lock guard <NUM>. In some examples, the guard recess <NUM> extends partially, but not entirely through the side frame <NUM>. An elongate shoulder <NUM> is then formed inward from an outermost surface <NUM> of the side frame <NUM>. In some examples, the perimeter of the elongate shoulder <NUM> mimics a portion of the frame lock guard <NUM>.

The frame lock guard <NUM> is positioned within the guard recess <NUM>. The frame lock guard <NUM> can be a generally flat, plate-like component that extends over at least a portion of the locking arm <NUM> to prevent incidental contact and actuation of the locking arm <NUM>. The frame lock guard <NUM> can be fastened or otherwise coupled to the side frame <NUM>. In some examples, the lock guard <NUM> includes a grip feature. For example, a protrusion or ridge <NUM> can extend away from a face surface <NUM> of the frame lock guard <NUM>. The ridge <NUM> can extend along a portion of the length of the frame lock guard <NUM>, and can be defined by a generally constant, semi-circular cross-section, for example. In some embodiments, the ridge <NUM> is defined by a curvature and extends concentrically with a portion of the outer perimeter of the frame lock guard <NUM>. The face surface <NUM> of the frame lock guard <NUM> can sit substantially flush with an outer surface of the side frame <NUM>, such that the ridge <NUM> extends outwardly beyond the side frame <NUM> to form a stop or grip. The guard recess <NUM>, which receives the frame lock guard <NUM>, can be formed with a depth that corresponds to a thickness of the frame lock guard <NUM> so the face surface <NUM> of the frame lock guard <NUM> is flush with the outer surface of the side frame <NUM>.

With continued reference to <FIG>, a longitudinal axis <NUM> is defined along the length of the knife <NUM> and a width axis <NUM> is defined perpendicular to the longitudinal axis <NUM>. The knife <NUM> is defined by a series of different length relationships that enable the frame lock knife <NUM> to function effectively and readily transition between the stowed position and the deployed position, and vice versa. For example, an arm and hinge length <NUM> is defined by the locking arm <NUM> and the living hinge <NUM> and measured parallel to the longitudinal axis <NUM>. An arm length <NUM> is defined by the locking arm <NUM> and measured parallel to the longitudinal axis <NUM>. A guard length <NUM> is defined by the frame lock guard <NUM> and measured parallel to the longitudinal axis <NUM>. Accordingly, the arm and hinge length <NUM>, the arm length <NUM>, and the guard length <NUM> are defined in parallel relation to one another along a length of the knife <NUM>, parallel to the longitudinal axis <NUM>.

The relationships between arm and hinge length <NUM>, arm length <NUM>, and guard length <NUM> can be chosen so that the locking arm <NUM> can provide the necessary bias on the blade <NUM> without being subjected to unwanted, friction-inducing forces that might otherwise impact the blade <NUM> from transitioning from the stowed position to the deployed position. For example, the ratio of guard length <NUM> to arm and hinge length <NUM> can be less than <NUM>% so that at least a portion of the locking arm <NUM> and living hinge <NUM> remain exposed outward beyond the frame lock guard <NUM>. This arrangement allows the locking arm <NUM> and hinge <NUM> to remain movable relative to the frame lock guard <NUM>, and provides areas of access so that a user can intentionally contact and actuate the locking arm <NUM> to transition the knife between deployed and stowed positions. In some embodiments, the guard length <NUM> is about sixty-six percent (<NUM> %) of the arm and hinge length <NUM>, allowing a portion of the living hinge <NUM> and a portion of the locking arm <NUM> to extend outwardly beyond each side of the frame lock guard <NUM>. In some embodiments, a ratio of the guard length <NUM> to the arm and hinge length <NUM> is between about fifty percent (<NUM> %) and about eighty percent (<NUM> %). The frame lock guard <NUM> can be positioned forward of the living hinge <NUM> so that the entire living hinge <NUM> is exposed relative to the frame lock guard <NUM>.

The frame lock guard <NUM> is designed to cover a significant portion of the locking arm <NUM>, so that incidental contact between the hands of a user and the locking arm <NUM> is limited or avoided altogether. The locking arm <NUM> can straddle the frame lock guard <NUM> so that a portion of the locking arm <NUM> extends outwardly from each side (e.g., the front side and back side, determined based upon relative position along the longitudinal axis <NUM>) of the frame lock guard <NUM>. By leaving a portion of the locking arm <NUM> uncovered by the frame lock guard <NUM>, a user can intentionally actuate the locking arm <NUM> by directly contacting the locking arm <NUM>. In some examples, the frame lock guard <NUM> is positioned toward the living hinge <NUM>, so that the distal end of the locking arm <NUM> remains readily accessible and movable by the fingers of a user. In some embodiments, a ratio of the guard length <NUM> to the arm length <NUM> can be about eighty-seven percent (<NUM> %). To create the necessary amount of accessibility to the locking arm <NUM> while still restricting unwanted actuation, the ratio of the guard length <NUM> to the arm length 88should be between about seventy-five percent (<NUM> %) to about one hundred percent (<NUM> %).

The longitudinal sizing and positioning, along with the width and latitudinal relationship (i.e., relative to the width axis <NUM>) of the frame lock guard <NUM> and locking arm <NUM> allow the frame lock guard <NUM> to prevent or inhibit incidental contact with the locking arm <NUM> while still allowing access to intentionally actuate the locking arm <NUM>. A series of dimensional relationships can again determine the frame lock guard's <NUM> effectiveness. For example, a locking arm width <NUM> is defined by the locking arm <NUM> in a direction parallel to the width axis <NUM>. The locking arm width <NUM> varies along the locking arm length <NUM>. In some embodiments, the locking arm width <NUM> is at a maximum proximate the living hinge <NUM>. The locking arm width <NUM> can be smaller at the distal end of the locking arm <NUM> than the proximal end of the locking arm <NUM>. A guard width <NUM> is defined by both the locking arm <NUM> and the frame lock guard <NUM> in a direction parallel to the width axis <NUM>. The guard width <NUM> is defined by the distance between the top side <NUM> of the locking arm <NUM> to the bottom side <NUM> of the frame lock guard <NUM>. The guard width <NUM> varies along the guard length <NUM> as well. Like the locking arm <NUM>, the guard width <NUM> can be at a maximum nearest the living hinge <NUM> and at a minimum nearest the distal end of the locking arm <NUM>.

In some embodiments, a ratio of the guard width <NUM> to the locking arm width <NUM> at any given position along the guard length <NUM> is between about forty-five percent (<NUM> %) and about seventy percent (<NUM> %) to allow a portion of the locking arm <NUM> to remain exposed below the frame lock guard <NUM>. In some embodiments, the ratio of the guard width <NUM> to the locking arm width <NUM> is about seventy percent (<NUM> %) at an end of the frame lock guard <NUM> distal from the blade <NUM> (i.e., proximate the living hinge <NUM>), and about forty five percent (<NUM> %) at an end of the frame lock guard <NUM> proximate to the blade <NUM> (i.e., proximate the distal end of the locking arm <NUM>). In some embodiments, the ratio of the guard width <NUM> to the locking arm width <NUM> is consistent (e.g., ~ <NUM> %) along the guard length <NUM>. In some embodiments, the ratio of the guard width <NUM> to the locking arm width <NUM> is between about thirty percent (<NUM> %) and about one hundred percent (<NUM> %).

As shown in <FIG>, the guard recess <NUM> is sized so that the face surface <NUM> of the frame lock guard <NUM> is flush with the outer surface of the side frame <NUM>. The locking arm <NUM> can also include an arm recess <NUM> shaped to receive a portion of the frame lock guard <NUM>. The arm recess <NUM> can be formed with a shape complimentary to the bottom side <NUM> of the frame lock guard <NUM>, and can be arranged to form a clearance fit around the frame lock guard <NUM> when the locking arm <NUM> is biased outward, into the unlocked position (which is located outward from the locked position shown in <FIG>). In some examples, engagement between the frame lock guard <NUM> and the base of the arm recess <NUM> can serve as a stop to prevent the locking arm <NUM> from being over-actuated outward, beyond the desired unlocked position. A depth of the arm recess <NUM> can be approximately equal to the thickness of the frame lock guard <NUM>, so that when the locking arm <NUM> is moved to the unlocked position, the outer surface of the side frame <NUM>, the face surface <NUM>, and the outer surface of the locking arm extend generally flush to one another.

<FIG> demonstrates the internal structure and fastening architecture of the knife <NUM>. In some examples, a liner <NUM> is fastened to the handle frame <NUM>. Because the handle frame <NUM> may be formed thinner than the side frame <NUM>, the liner <NUM> can be used to help balance and center the blade <NUM> within the handle assembly <NUM>. The liner <NUM> can be spaced apart from the side frame <NUM> by spacers <NUM>, which creates the cavity <NUM> that receives and protects the blade <NUM> in the storage configuration. While <FIG> shows the components of the knife <NUM> secured together using a plurality of different removable fasteners, various other coupling mechanisms and techniques can be used to create the knife <NUM>. In some embodiments, some or all parts of the handle assembly <NUM> are adhered, welded, brazed, fused, or otherwise connected or coupled without the use of removable fasteners.

<FIG> show the knife <NUM> in the storage position. The blade <NUM> is rotated toward the handle assembly <NUM>, so that the the cutting edge <NUM> is received within the cavity <NUM> and hidden within the handle assembly <NUM>. The portion of the blade <NUM> positioned within the cavity <NUM> interferes with the locking arm <NUM>, and prevents the locking arm <NUM> from reaching the locked position within the cavity <NUM>. Instead, the locking arm <NUM> is rotated about the living hinge <NUM> outward, into the unlocked position, with an end of the locking arm <NUM> resting on the blade <NUM>. The interference between the locking arm <NUM> resists, but does not prevent rotation of the blade <NUM> relative to the handle assembly <NUM> so that a user can still rotate the blade <NUM> to the deployed position. To deploy the blade <NUM>, a user can grab onto the blade <NUM> with one hand and grab onto the handle assembly <NUM> with the other hand. The opening aperture <NUM> is exposed and in a position that can be easily engaged by the user's thumb, and creates a grip point that can be pulled on to begin rotation of the blade <NUM> outward from the frame assembly <NUM>. The frame lock guard <NUM> is positioned so as to provide a gripping location for the user that allows the handle assembly <NUM> to be securely grasped without pressing on or impinging on the locking arm <NUM>. Pressing or otherwise forcing the locking arm <NUM> into the blade <NUM> can introduce additional friction and interference between the blade <NUM> and locking arm <NUM> that resists rotation toward the deployed position, which can be frustrating for a user. The frame lock guard <NUM> creates a barrier that impedes the hands of a user from contacting the locking arm <NUM>. In other words, the frame lock guard <NUM> inhibits accidental actuation of the locking arm <NUM> toward the locked position.

As shown in <FIG> and as explained above, the ridge <NUM> of the frame lock guard <NUM> projects outward of the face surface <NUM>. The ridge <NUM> protrudes farther from a center line of the handle assembly <NUM> than the locking arm <NUM> in the locked position (shown in solid lines) and the unlocked position (shown in dashed lines). The raised profile of the ridge creates a reference point and gripping section for the user, who can know without looking at the handle that his or her hands are positioned properly upon the frame lock guard <NUM> before deploying the blade <NUM> of the knife <NUM>. <FIG> also shows how the frame lock guard <NUM> is received within the arm recess <NUM> of the locking arm <NUM> while the locking arm <NUM> is arranged in the unlocked position.

<FIG> show additional details of the frame lock guard <NUM>. Specifically, the ridge <NUM> is an arcuate projection that protrudes from the face surface <NUM>. In some embodiments, the grip feature includes a knurled texture, studs, pyramidal protrusions, or a different shaped ridge. Additionally, the frame lock guard <NUM> is shown as a separate component that is fastened to the side frame <NUM>. In some embodiments, the frame lock guard <NUM> can be formed as a part of the side frame <NUM> or adhered to the side frame <NUM>, as desired.

The frame lock guard <NUM> advantageously inhibits a user from gripping or pressing on the locking arm <NUM> unintentionally. For example, as the user engages the opening aperture <NUM> on the blade <NUM>, if the user presses inadvertently on the locking arm <NUM>, the actuation of the blade <NUM> to the use position (see <FIG>) is inhibited and feels less than ideal to the user. The frame lock guard <NUM> inhibits the user from pressing the locking arm <NUM> inadvertently and avoids situation of less than smooth actuation between the use position and the storage position.

The construction and arrangement of the apparatus, systems and methods as shown in the various exemplary embodiments are illustrative only. Although only a few embodiments have been described in detail in this disclosure, many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters, mounting arrangements, use of materials, colors, orientations, etc.). For example, some elements shown as integrally formed may be constructed from multiple parts or elements, the position of elements may be reversed or otherwise varied and the nature or number of discrete elements or positions may be altered or varied. Accordingly, all such modifications are intended to be included within the scope of the present disclosure. Other substitutions, modifications, changes, and omissions may be made in the design, operating conditions and arrangement of the exemplary embodiments without departing from the scope of the present disclosure.

As utilized herein, the terms "approximately," "about," "substantially", and similar terms are intended to have a broad meaning in harmony with the common and accepted usage by those of ordinary skill in the art to which the subject matter of this disclosure pertains. It should be understood by those of skill in the art who review this disclosure that these terms are intended to allow a description of certain features described and claimed without restricting the scope of these features to the precise numerical ranges or geometric relationships provided. Accordingly, these terms should be interpreted as indicating that insubstantial or inconsequential modifications or alterations of the subject matter described and claimed are considered to be within the scope of the invention as recited in the appended claims.

Claim 1:
A knife (<NUM>) comprising:
a blade (<NUM>); and
a handle assembly (<NUM>) rotatably coupled to the blade (<NUM>), extending along a longitudinal axis (<NUM>), and including:
a side frame (<NUM>),
a handle frame (<NUM>) spaced apart from the side frame (<NUM>) and straddling a cavity (<NUM>) for the blade (<NUM>) extending therebetween;
a locking arm (<NUM>) coupled to the side frame (<NUM>) and movable between a locked position wherein the locking arm (<NUM>) extends partially into the cavity (<NUM>) and an unlocked position wherein less of the locking arm (<NUM>) extends into the cavity (<NUM>) than in the locked position, the locking arm (<NUM>) defined by an arm length (<NUM>) measured in a direction parallel to the longitudinal axis (<NUM>), and
a guard (<NUM>) coupled to the side frame (<NUM>) and overlaying at least a portion of the locking arm (<NUM>) along the longitudinal axis (<NUM>), the guard (<NUM>) being defined by a guard length (<NUM>) measured in a direction parallel to the longitudinal axis (<NUM>),
wherein a ratio of the guard length (<NUM>) to the arm length (<NUM>) is between about seventy-five percent (<NUM>%) to about one hundred percent (<NUM>%).