Retractable knife for rapid manual deployment while fully grasped

Abstract

A self-defense pocket knife with handle of suitable proportion to be grasped in closed fist and a conveyance system configured for the emergency manual conveyance of a blade from a position for storage to a position for use without requiring the user to appreciably alter or compromise grip upon the handle during the course of such conveyance.

Claims

1. A folding knife, comprising: a handle comprising a rear end, a forward end, a first side, a second side, a ring portion at the rear end configured to receive a finger of a user, a cavity extending into the ring portion, and a grasping portion between the rear end and the forward end; a locking element comprising a ring and a lockface extending radially outwardly from the ring, wherein the locking element is disposed in the cavity of the handle and is configured to pivot relative to the cavity of the handle; a blade having a base end and a tip end; and only two linking elements coupling the blade to the handle, including a first linking element and a second linking element, the first and second linking elements each having a first end portion and a second end portion, wherein the first end portions of the first and second linking elements are pivotably coupled to the first side of the handle, wherein the second end portions of the first and second linking elements are pivotably coupled to the blade, and wherein the second end portion of the second linking element comprises a boss, wherein the blade is translatable relative to the handle along an arcuate path between a use position and a storage position, wherein the base end and the tip end of the blade move from respective first locations closer to the rear end of the handle to respective second locations farther away from the rear end of the handle when the blade is translated along the arcuate path from the storage position to the use position, wherein when the blade is in the use position, the lockface of the locking element is configured to engage the boss of the second linking element, thereby selectively preventing movement of the blade from the use position to the storage position.

2. The folding knife of claim 1, wherein the handle further comprises a blade guard configured to shield a sharpened edge of the blade when the blade is in the storage position.

3. The folding knife of claim 2, wherein the blade guard is a recessed surface extending laterally from the first side of the handle toward the second side of the handle.

4. The folding knife of claim 1, further comprising a biasing element disposed in the cavity of the handle and configured to bias the lockface of the locking element against the boss of the second linking element.

5. The folding knife of claim 1, wherein the second linking element is disposed rearwardly relative to the first linking element, wherein the second end portion of the second linking element comprises an actuation surface configured to move the blade from the storage position to the use position when a user applies a forward force on the actuation surface.

6. A folding knife, comprising: a handle comprising a rear end portion, a forward end portion, a first side portion, a second side portion, a ring portion at the rear end portion, a cavity formed in the first side portion and extending into the ring portion, and a grasping portion disposed between the rear end portion and the forward end portion; a locking element disposed in the cavity of the handle, wherein the locking element includes a ring and a first boss projecting radially outwardly and perpendicular to a bore axis of the ring, wherein the locking element is configured to pivot relative to the cavity of the handle; a blade; and a front conveyance arm and a rear conveyance arm, the front and rear conveyance arms each having a first end portion and a second end portion, wherein the first end portions of the front and rear conveyance arms are pivotably coupled to the first side portion of the handle, wherein the second end portions of the front and rear conveyance arms are pivotably coupled to the blade, and wherein the second end portion of the rear conveyance arm includes a second boss, wherein the blade is translatable relative to the handle between a use position and a storage position, and wherein when the blade is in the use position, the first boss of the locking element is configured to interact with the second boss of the rear conveyance arm to selectively prevent the blade from moving from the use position to the storage position.

7. The folding knife of claim 6, wherein the handle further comprises a blade guard disposed on the first side portion and configured to shield a sharpened edge of the blade when the blade is in the storage position.

8. The folding knife of claim 7, wherein the blade guard is a recessed surface.

9. The folding knife of claim 6, further comprising a biasing element disposed in the cavity of the handle and configured to bias the first boss of the locking element against the second boss of the rear conveyance arm.

10. The folding knife of claim 6, wherein the second end portion of the rear conveyance arm comprises an actuation surface configured to move the blade from the storage position to the use position when a user applies a forward force on the actuation surface.

11. The folding knife of claim 6, wherein the first boss of the locking element comprises a lockface that is configured to interact with the second boss of the rear conveyance arm to selectively prevent movement of the blade from the use position to the storage position.

12. The folding knife of claim 6, wherein the first boss of the locking element comprises a detent that is configured to interact with the second boss of the rear conveyance arm to bias the blade to remain in the storage position.

13. A folding tool, comprising: a handle comprising a rear end, a forward end, a first side, a second side, an upper end, a lower end, a grasping portion, a ring portion, and a cavity, wherein the grasping portion is disposed between the rear end and the forward end, wherein the ring portion is disposed between the rear end and the grasping portion, and wherein the cavity is formed in the first side and extends from the ring portion toward the forward end; a locking element comprising a ring-shaped portion and a first boss extending radially outwardly from the ring-shaped portion, wherein the locking element is disposed in the cavity of the handle; a biasing element disposed in the cavity of the handle and positioned between the upper end of the handle and the first boss of the locking element; a movable component having a base portion and a tip portion; and a front conveyance arm and a rear conveyance arm, the front and rear conveyance arms each having a first end portion and a second end portion, wherein the first end portions of the front and rear conveyance arms are pivotably coupled to the first side of the handle, wherein the second end portions of the front and rear conveyance arms are pivotably coupled to the base portion of the movable component, and wherein the second end portion of the rear conveyance arm includes a second boss, wherein the movable component is translatable relative to the handle between a use position and a storage position, and wherein when the movable component is in the use position, the biasing element urges the first boss of the locking element against the second boss of the rear conveyance arm to selectively retain the movable component in the use position.

14. The folding tool of claim 13, further comprising a retaining member coupled to the handle and configured to retain the locking element in the cavity of the handle.

15. The folding tool of claim 14, wherein the handle further comprises a groove formed therein configured for receiving the retaining member.

16. The folding tool of claim 15, wherein the groove is formed in the ring portion of the handle.

17. The folding tool of claim 13, wherein the movable component comprises a cutting blade.

18. The folding tool of claim 13, wherein the handle further comprises a recessed surface disposed on the first side and configured to shield one or more portions of the movable component when the movable component is in the storage position.

19. The folding tool of claim 13, wherein the second end portion of the rear conveyance arm comprises an actuation surface configured to move the movable component from the storage position to the use position when a user applies a forward force on the actuation surface.

20. The folding tool of claim 13, wherein the first boss of the locking element comprises a lockface and a detent, wherein the lockface is configured to interact with the second boss of the rear conveyance arm to selectively retain the movable component in the use position, and wherein the detent is configured to interact with the second boss of the rear conveyance arm to bias the movable component to remain in the storage position.

Description

DESCRIPTION OF DRAWINGS

(1) The foregoing, as well as other objects of the present invention, will be made further apparent from the following detailed description of the present invention when taken together with the accompanying specification and drawings in which:

(2) FIG. 1A shows an orthogonal view of the present invention in such condition that the blade is in its position for storage.

(3) FIG. 1B shows an orthogonal view of the present invention in such condition that the blade is positioned partially between its position for storage and its position for use.

(4) FIG. 1C shows an orthogonal view of the present invention in such condition that the blade is in its position for use.

(5) FIG. 2A shows an exploded view of the present invention.

(6) FIG. 3A shows the present invention as it might appear in the hand and in such condition that the blade is in its position for storage.

(7) FIG. 3B shows the present invention as it might appear in the hand and in such condition that the blade is between its position for storage and its position for use.

(8) FIG. 3C shows the present invention as it might appear in the hand and in such condition that the blade is in its position for use.

(9) FIG. 4A shows a knife of prior art as it might appear in the hand and in such condition that the blade is in its position for storage.

(10) FIG. 4B shows a knife of prior art as it might appear in the hand and in such condition that the blade is in its position for use.

DETAILED DESCRIPTION

(11) A review of relevant prior art is necessary to properly appreciate the problems addressed by the present invention. To this end, FIGS. 4A and 4B depict a typical prior art folding karambit 5P held in a fist B, with index finger 70 (FIG. 4B) properly inserted through prior art ring portion 47P, and with fingers F securely encircling prior art handle 33P.

(12) FIG. 4A depicts prior art folding karambit 5P with prior art blade 31P in its position for storage and substantially encircled by fingers F comprising a fist B. Prior art blade 31P is configured to pivot about a rotational axis defined by prior art blade pivot 49P, resulting in rotational path of prior art blade R.

(13) Prior art folding karambit 5P, with prior art blade 31P in position for storage as shown in FIG. 4A, is desirable for use as an impact and compliance implement because of prior art impact/pressure surface A 30P, and prior art impact/pressure surface B 32P. Should the user wish to bring prior art blade 31P to bear (FIG. 4B), it can be readily appreciated that the position of fingers F of fist B are in conflict with rotational path of prior art blade R (FIG. 4A). Indeed, fingers F of fist B must be displaced from prior art handle 33P to accommodate rotational path of prior art blade R as prior art blade 31P is, in some fashion, conveyed from its position for storage to its position for use. As previously stated, the resulting period of delay and compromised control over prior art folding karambit 5P, in the context of combat-related crisis, is singularly undesirable.

(14) The present invention is responsive to this deficiency, as may be appreciated more fully in light of the following:

(15) FIGS. 1A to 1C illustrate the preferred embodiment of the present invention with blade 12 in its position for storage (FIG. 1A), an intermediate position between its position for storage and its position for use (FIG. 1B), and it position for use (FIG. 1C). Considered together with FIGS. 3A to 3C, which depict the present invention grasped in fist B and with blade 12 in its position for storage (FIG. 3A), intermediate between its position for storage and position for use (FIG. 3B), and in its position for use (FIG. 3C), the novel action of the present invention and how it diverges from prior art, detailed above, may be readily understood.

(16) FIG. 1A sets forth a view of the principle components comprising the present invention with blade 12 in its position for storage. A handle 10 is conveniently proportioned for grasping consistent with the style and traditional means of use of the implement, in this case a karambit knife. As a result, the preferred embodiment includes a prominent ring portion 46 (FIG. 1A) and a grasping portion G (FIG. 1B). Ring portion 46, constitutes a ring at one prominent end of handle 10 through which a user may insert index finger 70 (FIG. 3A). Grasping portion G (FIG. 1B) is of suitable size and contour to accommodate fingers F (FIGS. 3A, 3C) for grasping the present invention while in use. Handle 10 further includes a blade guard 48 configured to partially shield blade edge 50 and blade point 52 while blade 12 is in its position for storage, protecting against unintentional interaction (FIG. 1B).

(17) Front conveyance arm 14 and rear conveyance arm 16 are elongated linking elements with instances of pivot hole 72 (FIG. 2A) located near the two prominent ends of each. FIG. 1B shows front conveyance arm 14 and rear conveyance arm 16 pivotably mounted to handle 10 and blade 12 by multiple instances of pivot element 22 in conjunction with multiple instances of pivot hole 72 (FIG. 2A).

(18) The angle of blade edge 50 of blade 12 with respect to handle 10 is determined by the relative length of front conveyance arm 14 and rear conveyance arm 16 with regard to each other, and the positions of fore pivot hole/handle 66, aft pivot hole/handle 68, and fore pivot hole/blade 62 and aft pivot hole/blade 64 (FIG. 2A). A large degree of flexibility is therefore available for altering the angle of blade 12 relative to handle 10 in both position for storage and in position for use as may be desirable with regard to alternative embodiments.

(19) Most importantly, FIGS. 3A to 3C show that blade 12 does not follow the rotational path of prior art blade R (FIG. 4A) wherein prior art blade point 53P travels approximately 180 degrees about a single rotational axis defined by prior art blade pivot 49P. Rather, blade 12 of the present invention is impelled along a novel conveyance path P (FIG. 3B) that does not require fingers F (FIG. 3A) to be displaced from handle 10 as blade 12 moves between its position for storage and its position for use.

(20) Furthermore, manually impelling blade 12 along conveyance path P to its position for use is conveniently accomplished with a comparatively intuitive movement of thumb 71 acting upon an actuation surface 24 (FIGS. 3A, 1A). For the purposes of the preferred embodiment, actuation surface 24 defines a contour at one prominent end of rear conveyance arm 16. Other embodiments may easily include additional levers to operationally act upon actuation surface 24 which itself may be relocated to another portion of front conveyance arm 14, rear conveyance arm 16, or blade 12 without substantially departing from the substance of the present invention.

(21) A closer examination of FIG. 3A shows thumb 71 contacting actuation surface 24, with fingers F of fist B encircling handle 10. This grip is effectively comparable to that of prior art folding karambit 5P (FIG. 4A) and impact/pressure surface A 26, and impact/pressure surface B 28 are exposed for use (FIG. 3A). The tightening of fist B increases pressure on heel portion 60 of blade 12 (FIG. 1A) compelling blade 12 toward its position for storage. As a result, impacts directed toward impact/pressure surface A 26 and impact/pressure surface B 28, do not induce unintended movement of blade 12 toward its position for use (FIG. 3A).

(22) FIG. 3B depicts thumb 71 impelling blade 12 toward its position for use. Though distended, fist B substantially maintains its integrity and there is no need to engage a second hand or alternate means to compel blade 12 toward its position for use. FIG. 3C displays blade 12 fully extended into its position for use with fingers F maintaining position with regard to fist B.

(23) While in its position for use, blade 12 is prevented from further extension by means of blade stop/open 56 on handle 10 which is configured to interact with positional index surface 54 on blade 12 (FIG. 1B). Conversely, defining the limit of blade travel toward its position for storage, positional index surface 54 of blade 12 interacts with blade stop/closed 58 on handle 10.

(24) The following description of locking and closing-detent means concerns the preferred embodiment of this disclosure. A great variety of locks and closing-detent means may be readily adapted to the present invention. As a result, blade lock and closing-detent means disclosed herein should not be considered limiting with respect to the scope of the present invention.

(25) A locking element 18 and its interaction with other parts in assembly may be best understood in light of FIG. 1C and FIG. 2A. Locking element 18 defines the general form of a ring with elongated boss projecting substantially radially outwardly and generally perpendicular to the ring's bore axis (FIG. 2A). Locking element 18 fits into cavity 44 in handle 10 and is substantially concentric to and pivots about a rotational axis defined by a ring-shaped portion of cavity 44 as cavity 44 extends into ring portion 46 of handle 10.

(26) Retaining ring 20 fits into retaining ring groove 38 in handle 10, securing locking element 18 into cavity 44 without obstructing rotational movement of locking element 18.

(27) FIG. 2A further shows biasing element 36 configured to provide a directional urging for locking element 18 as may be readily appreciated by its location within the depicted assembly of the preferred embodiment. Locking element 18 includes a lockface 42 that, in conjunction with the influence of biasing element 36, is configured to interact with boss 40 of rear conveyance arm 16 so that when blade 12 is in its position for use, movement of rear conveyance arm 16 is selectively prevented. As a consequence, movement of blade 12 toward its position for storage is likewise selectively prevented.

(28) Locking element 18 further incorporates detent 43 configured to interact with boss 40 of rear conveyance arm 16 so that, in conjunction with the influence of biasing element 36, a biasing effect is provided, urging blade 12 to remain in its position for storage. In context of use, this urging may be overpowered by thumb 71 acting upon actuation surface 24 as it impels blade 12 toward its position for use (FIGS. 3A to 3C).

(29) An additional benefit inherent to the present invention is enhanced user safety with regard to the consequences of potential lock failure. While many locking means have been devised for folding knives and subsequently adapted to folding karambits, a conspicuous hazard remains for the user of prior art folding karambit 5P (FIGS. 4A, 4B) in the event of sudden lock failure. As previously described in detail, fingers F must be removed from prior art handle 33P to allow prior art blade 31P to move along rotational path of prior art blade R. In view of FIGS. 4A,4B, the consequences of lock failure resulting in prior art blade 31P forcefully returning to its position for storage along rotational path of prior art blade R, while fingers F remain encircling prior art handle 33P are considerable.

(30) By contrast, the benefit of the present invention in this regard might be readily appreciated in view of FIGS. 3A to 3C. In particular, FIG. 3B illustrates the approximate position blade 12 should be expected to assume in the event of catastrophic lock failure resulting in blade 12 being forcefully compelled toward its position for storage. Of note is the comparatively safe position of blade edge 50 with respect to fingers F, and the comparatively safe trajectory of blade edge 50 with respect to fingers F as blade 12 is moved in a reverse direction of conveyance path P, toward its position for storage. Indeed, as configured, blade 12 is inherently incapable of movement analogous to the potentially hazardous rotational path of prior art blade R (FIG. 4A).

(31) While embodiments of the present invention have been illustrated and described using specific terms, such description is for present illustrative purposes only and it is to be understood that changes and variations to such embodiments, including but not limited to the substitution of equivalent features of parts and the reversal of various features thereof, may be practiced by those of ordinary skill in the art without departing from the spirit or scope of the following claims.