Abstract: A folding knife incorporates an opening assist mechanism that functions to drive the blade from the closed to the open position. A pair of torsion springs held axially on the blade axis pin and within a pair of bushings are stationary relative to the knife handle. One leg of each spring is fixed to a bushing. The opposite leg of the spring rides in a pocket formed in the surface on the blade axially around the opening through which the blade axis pin is inserted. As the blade rotates from the closed position toward the open position, the legs of the springs rotate through and cooperate with structures formed on the bushings to transfer the spring pressure instantly to the blade to drive the blade open.

Abstract: The folding knife of the present invention includes a handle having first and second handle members that are maintained in spaced, parallel relation to one another by spacing elements that define a groove therebetween. The blade is pivotally attached to the handle at its tang portion and is movable into and out of the groove between its fully open and fully closed positions. A coil spring, or equivalent, may be interconnected between the tang and handle to provide an assisted opening mechanism. A blade lock includes a user actuated button that passes through an elongated slot formed through one of the handle members and through a circular opening formed through a bias plate that is positioned within the handle, and a plunger element that is spring biased in a direction transverse to the longitudinal axis of the blade.

Abstract: A flick knife with a lever frame has a hilt, a blade, a lever frame and a spring. The blade has a proximal end pivotally mounted in the hilt. The lever frame is mounted through the hilt and has a front connector that abuts the proximal end of the blade to rotate the blade, and a rear connector. The spring is mounted inside the hilt and connects the hilt to the rear connector of the lever frame and eases opening of the blade and prevents the blade from opening. Because the spring is mounted in the hilt, the knife is thinner than prior art and therefore more convenient.

Abstract: A folding hand tool with an open-assist mechanism that is not mechanically linked to a folding knife blade is disclosed. The open-assist mechanism is allowed to rotate around the same pivot used by the blade, and includes a lug that interacts with the kick of the blade when rotated. Because the open-assist mechanism is not mechanically linked to the blade, it has a range of free motion that promotes safety, and allows the mechanism to rotate into the blade cavity when the blade is extended. The folding knife also may have a carabiner that shares the blade cavity with the blade, with the blade nesting into the carabiner to save space, thereby giving the folding knife a smaller profile.

Abstract: A knife with a spring-assisted articulation mechanism for assisting the user in the folding and unfolding of the blade from the pocket of the liner. The spring-assisted articulation mechanism also helps retain the blade in the folded position to prevent the blade from becoming unintentionally unfolded. The knife includes a pocketed liner and a blade attached to liner at one end of the liner by a pivot pin. The blade has a pointed end and a base end, the base end pivotally secured to the second end of the liner by the pivot pin such that the blade is capable of pivoting between a folded “closed” position and an unfolded “open” position. A guide pin is also attached to the blade of the knife at the base. A spring is provided to exert a closing force on the blade when the blade is in the closed position and an opening force on the blade when the user moves the blade into a partially open position.

Abstract: A cutting tool having a body, a first scissors tool coupled with the body and having a first pair of blades cooperating to define a first cutting pattern, and a second scissors tool coupled with the body and having a second pair of blades cooperating to define a second cutting pattern.

Abstract: In certain embodiments of the present disclosure, a folding knife has a biasing mechanism, such as a spring, that applies an opening force to the blade when the blade is in the closed, or folded, position (i.e., the force of the spring creates a moment in the opening direction of the blade). The folding knife includes a latching mechanism that holds the blade in a closed and latched position against the opening force of the spring. To open the blade, manual pressure is applied to the upper edge of the blade (the edge opposite the sharpened edge) to move the blade slightly to a closed and unlatched position to release the blade from being held from the latching mechanism whereupon the blade is then free to pivot under the opening force of the spring.

Abstract: A folding knife has a handle, a blade, a locking rod and an unlocking lever. The handle has a dorsal portion. The blade is pivotally mounted and selectively folded in the handle and has a notch. The notch is formed on a spine of the blade. The locking rod is mounted on the dorsal portion of the handle and has a locking end and a protrusion. The protrusion is formed on the locking end and engages the notch of the blade. The unlocking lever is pivotally mounted on the handle and has a pushing end and at least one propping block. The propping block protrudes from the unlocking lever and abuts the locking rod. Therefore, the folding knife allows users to release the blade by either directly pressing the locking rod or pushing the pushing end of the unlocking lever.

Abstract: The present invention discloses a folding knife, which includes a knife handle having a slot; a blade pivotally coupled to the knife handle and turnable into or out from the knife handle; a resilient device fixed to the knife handle and extended to a position proximate to the pivotal connecting position, such that when the blade is stored completely into the knife handle, the resilient device produces a torque to turn the blade into the knife handle, and when the blade is turned to a predetermined angle out of the knife handle, the resilient device produces a torque to turn the blade out from the knife handle; and a turning device, pivotally coupled to the knife handle and having a protruding pillar passed through the slot for securing or releasing the blade as required.

Abstract: The present invention discloses a folding knife, which includes a knife handle having a slot; a blade pivotally coupled to the knife handle and turnable into or out from the knife handle; a resilient device fixed to the knife handle and extended to a position proximate to the pivotal connecting position, such that when the blade is stored completely into the knife handle, the resilient device produces a torque to turn the blade into the knife handle, and when the blade is turned to a predetermined angle out of the knife handle, the resilient device produces a torque to turn the blade out from the knife handle; and a turning device, pivotally coupled to the knife handle and having a protruding pillar passed through the slot for securing or releasing the blade as required.

Abstract: A foldable knife comprises a blade having an end pivotally connected to an end of a handle, and a spring having two ends connected to the handle and blade respectively, so that the spring can apply a torque to the blade to rotate the blade out of the handle. A blocking element is provided at an inner portion of the handle. A switch element pivotally connected to the inner portion of the handle has a first end extended out of the handle. When the blade is completely received in the handle, a second end of the switch element bears against the blade. When the user pushes the first end of the switch element, a positioning portion formed on the blocking element is disengaged from an engaging portion formed on the blade, so that the torque of the spring drives the blade to spring out of the handle.

Abstract: A folding knife incorporates an opening assist mechanism that functions to drive the blade from the closed to the open position. The knife may be either automatic or semi-automatic. In one embodiment a pair of spring arms, one located to each lateral side of the blade is interconnected at their forward ends with a pin and a roller sleeve. The spring arms apply pressure to the tang of the blade when the blade is closed.

Abstract: A fishing knife has a handle defining a blade slot and a blade pivotally mounted between open and closed positions on a pivot pin extending through the handle. The blade has a tip, a sharp edge and back. A line cutter including a recess is defined in the blade back and a line cutting edge extends across the recess. The recess is disposed away from the tip of the blade. The line cutter is a replaceable cutter insert received in a matingly configured slot defined by the blade. The handle defines a recess cooperatively that exposes the line cutting edge when the blade is closed. The blade defines an arcuate pivot slot having enlarged lock openings at each end. A spring biased blade lock plunger extends through the pivot slot, and has a lock portion that fits in the lock openings to secure the blade in closed and open positions. The plunger is axially shiftable to position a release portion in the pivot slot, permitting the blade to pivot.

Abstract: A biasing system for the blade of a folding knife includes one component or assembly applying a force tending to move the knife blade from a closed position, nested in the handle, to an open position, extending from the handle. A second component or assembly resists opening of the blade, particularly when the blade is in or near the closed position. The resisting force is overcome by the opening force after the blade has been moved through a predetermined angle relative to the handle, so that the blade then opens automatically. A safety can be actuated to block opening and/or closing of the blade. The blade can have a blunt projection upon which a user may press to move the blade through the predetermined opening angle. A clip can be provided for convenient attachment of the folding knife to an object such as a garment.

Abstract: A folding knife with thumb release opening includes a knife blade, a first liner plate, a second liner plate, a first handle plate and a second handle plate. The knife blade includes a cutting edge and a point formed on a first end. A second end of the knife blade is pivotally retained by a first end of first and second liner plates. A push button is retained in the knife blade. A liner lock is formed in the second liner plate. A lock pin is pressed into an end of the liner lock and a lock hole is formed in the second end of the knife blade to receive the lock pin. The first and second handle plates cover the first and second liner plates. The push button may be replaced with a thumb disc. A second embodiment includes spring assisted opening and a third embodiment includes automatic opening.

Abstract: A folding knife includes a handle, a blade, a resilient element and a poking element. The blade can be turned into or out from the handle. The resilient element has an end fixed to the handle and another end extended to a position of connecting the handle and the blade. If the blade is stored in the handle, the resilient element produces a torque to turn the blade into the handle. When a force is applied to turn the blade out from the handle, the resilient element produces a torque to pop the blade out from the handle automatically. The poking element is provided for turning the blade. When the blade is in the handle, the poking element presses against the blade, such that if a user pokes an end of the poking element, another end of the poking element turns the blade out from the handle.

Abstract: A folding knife incorporates an opening assist mechanism that functions to drive the blade from the closed to the open position. The mechanism of the present invention relies upon a pair of torsion springs held axially on the blade axis pin and within a pair of bushings that are stationary relative to the knife handle. There is one spring and one bushing on each lateral side of the blade. One leg of each spring is fixed to the bushing. The opposite leg of the spring rides in a pocket formed in the surface on the blade axially around the opening through which the blade axis pin is inserted. When the blade is in the closed position the torsion springs are “loaded” but do not apply their spring force to the blade, instead applying their force against the stationary bushing.

Abstract: A utility knife having a handle and a blade holder which is pivotally mounted on the handle for movement from an unfolded position to a folded position. The handle has a space adapted to receive the blade holder when the blade holder is in its folded position. A spring pressed lock plug is provided to move into and out of the space to hold the blade holder in the folded and unfolded positions. The blade holder includes a main wall and guard wall pivotally mounted on the main wall to pivot from an open position to a closed position overlying the main wall. The main wall being adapted to hold a blade so that a blade is interposed between the main wall and guard wall when the guard wall is in its closed position.

Abstract: The invention discloses a folding knife having a knife handle and a blade. A pivotal shaft is at an end of the knife handle; a limit slot is inside the knife handle; and a latch element is in the limit slot. The blade is pivotally coupled to the knife handle through the pivotal shaft. The blade includes a protruding pillar corresponding to a latch portion. When the blade is stored into the knife handle, the protruding pillar is fixed between the limit slot and the latch element, and the blade will not pivot out of the knife handle due to shakes or vibrations. If a predetermined force is applied to rotate the blade towards the knife handle, the protruding pillar will rotate in conformity with the blade and push the latch element, so that the protruding pillar is released and rotated with the blade in the limit slot.

Abstract: A flick knife with a lever frame has a hilt, a blade, a lever frame and a spring. The blade has a proximal end pivotally mounted in the hilt. The lever frame is mounted through the hilt and has a front connector that abuts the proximal end of the blade to rotate the blade, and a rear connector. The spring is mounted inside the hilt and connects the hilt to the rear connector of the lever frame and eases opening of the blade and prevents the blade from opening. Because the spring is mounted in the hilt, the knife is thinner than prior art and therefore more convenient.

Abstract: A folding knife includes a handle and a blade attached thereto and configured to rotate between an open position and a closed position. A locking element is coupled to the handle, while a pawl is coupled to the blade and configured to engage the locking element as the blade rotates to the closed position, such that the blade is locked in the closed position thereby. Opening pressure on the pawl causes it to release the locking element and also causes the blade to rotate from the closed position toward the open position. The knife blade may include a flicker positioned to extend from a back portion of the handle when the blade is in the closed position. The pawl is coupled to the flicker such that pressure on the flicker causes the pawl to release the locking moves the blade toward the open position. The folding knife may also include an opening assist mechanism.

Abstract: A folding knife is disclosed. The folding knife includes a handle; a blade connected to the handle in a manner allowing pivoting of the blade between a closed position in which the blade extends along the handle, and an open position in which the blade extends away from the handle; and a blade-assisting mechanism including a biasing assembly and a housing, wherein the biasing assembly is configured to urge the blade towards at least one of the open position and the closed position over at least a portion of the blade travel between the closed position and the open position, and the housing encloses at least a portion of the blade-assisting mechanism, and wherein the blade-assisting mechanism is configured to be removably mounted between the blade and the handle.

Abstract: A folding tool with inlay release preferably includes a blade, a lock side plate, a release side plate, a cantilever spring and a release inlay. One end of the blade is pivotally retained between the lock side plate and the release side plate. One end of the cantilever spring is attached to the lock side plate and the other end is biased to contact the one end of the blade. A rocker bar is pivotally retained in the release side plate. One end of the rocker bar captures a biased end of the cantilever spring. The release inlay is used to pivot the other end of the rocker bar to release the one end of the rocker bar to allow the blade to be released from a closed position. A slide lock prevents the rocker bar from being released by the release inlay.

Abstract: A multiblade knife unit includes knife blades of different type normally stored within and adapted for deployment from a common end of a handle housing. A pivoting knife blade is supported for pivotal movement between a stored position nested substantially within one side edge of the handle housing, and a deployed position projecting from one end of the handle housing. A razor-type utility knife blade is supported by a slide clip for sliding displacement between a retracted position stored and concealed within the handle housing, and an advanced position projecting from said one end of the handle housing. A release button on the handle housing is depressed for releasing the utility knife blade from the slide clip for facilitating quick and easy slide-out blade removal and replacement. In one form, the knife unit may further include driver bits interchangeably mounted at an opposite end of the handle housing.

Abstract: A folding knife having a safety lock moveably mounted on a handle of the knife. The safety lock may slide to a locking position to prevent the blade from opening out of the handle by obstructing the path of the blade as the blade is urged from a closed position to an open position. The safety lock also may slide away from the locking position, in which the safety lock does not obstruct the path of the blade.

Abstract: A medical instrument especially suited for the HALS operating technique that can be entirely inserted together with one of the surgeon's hands into the operating area for operating purposes and includes a housing [(1)] and at least one tool [(2)] arranged in the housing [(1)], where the tool [(2)] can be moved between a rest position arranged in the housing [(1)] and a working position extending out of the housing [(1)].

Abstract: A spring assist folding knife and method of biasing a blade in a folding knife. The folding knife includes a blade, liner, and handle. The blade includes a first recess for receiving a pivot pin. The blade includes a second recess offset from the axis of rotation. A latch cam having an offset pin is located relative to the second recess. The liner includes an arcuate slot in which the offset pin of the latch cam is located. The arcuate slot within the liner or handle also includes a convex extension. A spring is configured to provide a force in the direction of blade opening and provides the force throughout the entire range of blade motion. The spring applies its force to the offset pin to bias the blade in the closed position until the blade reaches a predetermined angle. Then the spring biases the blade to the open position.

Abstract: A folding knife having a handle including a first side and a second side spaced apart to define a cavity; a blade including a cutting surface and a tang; and a holding mechanism including a piston adapted to be manually moved and having a first stop element of a first dimension and a first opposing element of a second dimension greater than the first dimension, at least a second stop element fixed on the tang, and at least a second opposing element also fixed on the tang, the first opposing element being adapted to be moved to a hold position when the blade is in one of the closed and open positions, in which the first opposing element seats against the second opposing element, the first stop element substantially engages the second stop element, and the blade is held in the one position.

Abstract: A folding knife is disclosed. The folding knife includes a handle; a blade connected to the handle in a manner allowing movement of the blade between a closed position in which the blade extends along the handle and an open position in which the blade extends away from the handle; and a blade-assisting mechanism configured to apply a manually adjustable force to urge the blade towards the open position over at least a portion of the blade travel between the closed position and the open position.

Abstract: A folding knife incorporates an opening assist mechanism that functions to drive the blade from the closed to the open position. The knife may be either automatic or semi-automatic. In one embodiment a pair of spring arms, one located to each lateral side of the blade is interconnected at their forward ends with a pin and a roller sleeve. The spring arms apply pressure to the tang of the blade when the blade is closed.

Abstract: A folding knife having a handle and a blade pivotally attached to the handle for pivoting between a retracted position and an extended position. A cantilever member is connected to the handle, and the cantilever member includes a free end. The blade includes a first stop and a second stop, and the first stop and the cantilever member are configured such that upon the blade being in the retracted position, the free end of the cantilever member bears against the first stop to selectively maintain the blade in the retracted position.

Abstract: A hand tool such as a folding knife that incorporates a blade stop pin that stops rotation of the blade in the open position is described. The stop pin defines a multifaceted face having plural surfaces, each having a radial distance from an axial centerline that is different from adjacent surfaces. Rotation of the stop pin allows for adjustment of the stop position of the blade.

Abstract: An automatic folding knife having a sear provided on a pivoting blade, and an engagement member, configured for upward movement, for selectively engaging the sear. The engagement member extends generally to the exterior of each side portion of the handle. A spring-biased cable biases the blade towards the extended position, and the engagement member is configured for engaging the sear upon the blade being in the retracted position. The blade is configured to automatically pivot from the retracted position to the extended position upon the engagement member being lifted upwardly, and the engagement member also automatically locks the blade in the extended position. The knife can readily be converted to an assisted opening knife having in significant part the components of the automatic knife.

Abstract: A folding knife with opening and closing assistance preferably includes a blade, a first frame, a second frame, a coil spring, an open lock pin and a closed lock pin. One end of the blade is pivotally retained between one end of the first and second frames. The open lock pin is preferably retained in the second frame. An open lock notch is formed in a first end of the blade such that the blade may be locked in an open position with the open lock pin. The closed lock pin is radially spring loaded between the first and second frames. A closed lock notch is formed in the first end of the blade to receive the closed lock pin. The blade is locked in a closed position, when the closed lock pin is retained in the closed lock notch.

Abstract: A folding knife includes a handle having a distal portion and a proximal portion, and a blade rotatably connected to the distal portion of the handle. The blade may be moveable between an opened position and a closed position, and may have at least one lock member receiving recess formed therein. The folding knife may further include a lock bar pivotally connected to a medial portion of the handle and moveable between an engaged position and a disengaged position. The lock bar may include a lock member which contacts a respective portion of the blade adjacent the lock member receiving recess to define a contact point between the lock member and the blade when the blade is in the opened position and the lock bar is in the engaged position. The folding knife may also include a lock pin connected to the handle adjacent the lock member.

Abstract: A frame member for the handle of a folding knife or multipurpose tool includes an integral flange with an integral leaf spring. Frames are shown in the form of a channel with an integral external flange extending outwardly from the top of a channel wall in a direction away from the channel. Pivot pins extending through the channel and out the channel wall carry pivoting tool blades. An integral leaf spring on the external flange bears against the base of a blade pivotably connected to the frame outside of the channel. Other tool blades are carried inside the channel and pivot about the pivot pin.

Abstract: In one embodiment of the present invention a laterally folding knife is described incorporating an actuator mechanism permitting the knife blade to be moved from open and closed positions without the need for a user to touch the blade. Further, the folding knife can be quickly opened or closed using a single finger or thumb. The knife blade is automatically locked in place in either open or closed position and therefore does not require a separate blade locking mechanism.

Abstract: An assisted opening folding knife having a blade with an engagement surface extending generally radially outwardly with respect to the pivot axis of the blade. A cantilevered leaf spring contacts the engagement surface and immediately urges the blade to the extended position upon the blade pivoting through a predetermined angle from the retracted position. An elongated engagement member is pivotally connected to the handle and configured for pivoting between a blade locking position and an unlocking position. In one embodiment, the cantilevered leaf spring also urges the engagement member towards the blade locking position. The engagement member automatically locks the blade in the extended position, and the cantilevered leaf spring, the blade, and the engagement member all substantially extend in the pivot plane.

Abstract: A “spring powered toggle joint lock” for a folding knife; comprising a blade lock of three primary elements. A rotating toggle link at the rear of the knife handle connected by a pivoting knee joint to a traveling toggle, which is in turn pivotally joined to the tang of the opening and closing blade. A spring configured so as to constantly urge the pivot points of the rotating toggle and traveling toggle into a straight line, generating an over-center action. The effect of the spring and toggle combination is to propel the opening blade towards open and the closing blade towards closed. Control pins attached to the traveling toggle and protruding to the surface of the handle, on both sides of the handle, provides the means to collapse the toggle lockup by thumb pressure, thereby allowing ambidextrous, one handed manipulation of a toggle locking folding knife.

Abstract: A spring assist folding knife and method of biasing a blade in a folding knife. The folding knife includes a blade, liner, and handle. The blade includes a first recess for receiving a pivot pin. The blade includes a second recess offset from the axis of rotation. A latch cam having an offset pin is located relative to the second recess. The liner includes an arcuate slot in which the offset pin of the latch cam is located. The arcuate slot within the liner or handle also includes a convex extension. A spring is configured to provide a force in the direction of blade opening and provides the force throughout the entire range of blade motion. The spring applies its force to the offset pin to bias the blade in the closed position until the blade reaches a predetermined angle. Then the spring biases the blade to the open position.

Abstract: A folding knife according to one embodiment is provided and includes (a) a handle defining a blade cavity; (b) a blade having a first end which is pivotably coupled to the handle about a pivot; and (c) a biasing element disposed within the blade cavity of the handle. The blade has a detent formed therein on a lower edge thereof proximate to the pivot. The biasing element has a fixed first end and an opposing free second end which has a rounded ball member formed thereat. As the blade is closed towards the retracted position, the blade contacts and deflects the second end of the biasing element until the rounded ball member of the second end engages the blade detent, resulting in the blade being held in the retracted position.

Abstract: A folding knife, comprising a blade pivotally connected to an elongate handle defining a recessed blade cavity and a blade opening assembly constructed and arranged to assist movement of the blade to an open position, in which the blade is extended. The blade opening assembly comprises, in one example, a bias element and an actuating member. The bias element is housed within the recessed blade cavity and has a free end. The actuating member is pivotally connected to the handle within the recessed blade cavity and is constructed and arranged to engage a portion of the tang of the blade and a portion of the bias element such that the blade may be assisted to the open position. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. 37 C.F.R.

Abstract: A folding knife light tool with an ergonometric handle in which an illuminating means whether an LED or light bulb or a laser light is incorporated into the handle housing in the spaces existing between the blade, the locking mechanism, and the handle. A knife handle is provided having a body contoured for the hand. The housing is made from one molded piece with a slit in the middle. The handle includes a pivot point for supporting a blade between the longitudinal sides or scales of the blades. A conventional locking or non-locking system is utilized for keeping the blade open once it is unfolded. When the blade is folded, a portion of the blade extends above the sides of the knife handle for digital engagement in the opening operation.

Abstract: A utility knife having a handle and a blade holder which is pivotally mounted on the handle for movement from an unfolded position to a folded position. The handle has a space adapted to receive the blade holder when the blade holder is in its folded position. The blade holder includes a main wall and guard wall pivotally mounted on the main wall to pivot from an open position to a closed position overlying the main wall. The main wall being adapted to hold a blade so that a blade is interposed between the main wall and guard wall when the guard wall is in its closed position.

Abstract: A folding knife having a blade and integral tang pivotally mounted to a handle with a cantilever spring fixedly attached at one end to the handle and extending to a free, terminal end having a lobed portion. A camming member fixed to the tang has a camming surface spaced from the pivot axis extending through the tang. The lobed portion of the spring contacts the camming surface when the blade is in the fully closed position and remains in contact throughout a first portion of the blade movement toward the open position. The spring is out of contact with the camming surface during a second portion of blade movement, from the end of the first portion to the fully open position. Momentum developed by spring force applied to the camming member during the first portion of blade movement is sufficient to move the blade through the second portion of its movement to the fully open position.

Abstract: A spring assist folding knife and method of biasing a blade in a folding knife. The folding knife includes a blade, liner, and handle. The blade includes a first recess for receiving a pivot pin. The blade includes a second recess offset from the axis of rotation. A latch cam having an offset pin is located relative to the second recess. The liner includes an arcuate slot in which the offset pin of the latch cam is located. The arcuate slot within the liner or handle also includes a convex extension. A spring is configured to provide a force in the direction of blade opening and provides the force throughout the entire range of blade motion. The spring applies its force to the offset pin to bias the blade in the closed position until the blade reaches a predetermined angle. Then the spring biases the blade to the open position.

Abstract: A folding tool such as a knife or multitool has a handle defined by opposed side walls with a slot therebetween. An implement such as a blade is pivotally connected to the handle. A spring such as a liner disposed between the implement and one side wall has a longitudinal slot cut therein and opening on the end adjacent the implement attachment to define a spring arm. The slot includes a constricted zone that is preferably substantially V shaped and has an apex aligned with the pivot axis of the implement. A pin on the implement rides in the slot. When the pin is on the rearward side of the apex the spring arm applies pressure to the implement and prevents it from moving into the open position. The implement is thus safely and securely locked into the handle.

Abstract: A folding tool such as a knife or multitool has a handle defined by opposed side walls with a slot therebetween. An implement such as a blade is pivotally connected to the handle. A spring such as a liner disposed between the implement and one side wall has a longitudinal slot cut therein and opening on the end adjacent the implement attachment to define a spring arm. The slot includes a constricted zone that is preferably substantially V shaped and has an apex aligned with the pivot axis of the implement. A pin on the implement rides in the slot. When the pin is on the rearward side of the apex the spring arm applies pressure to the implement and prevents it from moving into the open position. The implement is thus safely and securely locked into the handle.

Abstract: The present invention relates to a foldable knife structure, which comprises a handle; a blade pivotably conjoined to a position adjacent to one end of the said handle; a set block adjacent to the pivotable conjoinment position of the blade and the said handle, with the said set block having a detent notch; a spring situated at the other end of the said handle, with the opposite extremity of the said spring extending to a position on the said set block. When the said blade is extended from (or folded into) the said handle, the said spring is against the circumferential edge of the said set block, causing the said set block to produce torsion that rotates the said blade out of (or into) a receiving slot of the said handle, causing the said blade to automatically bound out of (or fold into) the said receiving slot.

Abstract: The present invention relates to a foldable knife structure, which comprises a handle; a blade pivotably conjoined to a position adjacent to one end of the said handle; a set block adjacent to the pivotable conjoinment position of the blade and the said handle, with the said set block having a detent notch; a spring situated at the other end of the said handle, with the opposite extremity of the said spring extending to a position on the said set block. When the said blade is extended from (or folded into) the said handle, the said spring is against the circumferential edge of the said set block, causing the said set block to produce torsion that rotates the said blade out of (or into) a receiving slot of the said handle, causing the said blade to automatically bound out of (or fold into) the said receiving slot.