Releasable double locking knife

Information

  • Patent Grant
  • 6701621
  • Patent Number
    6,701,621
  • Date Filed
    Wednesday, May 8, 2002
    22 years ago
  • Date Issued
    Tuesday, March 9, 2004
    20 years ago
Abstract
A releasable, double locking knife including a body having a cavity and a pair of opposed arms, each having a free end extending into the cavity, and a blade connected to the body for rotation between the closed position wherein the blade is disposed substantially within the cavity and an open position wherein the blade is disposed substantially outside the cavity. The opposed arms engage side surfaces of the blade when the blade is in the closed position to resist movement of the blade out of the closed position. The arms further engage stop surfaces on the blade when the blade is in the open position, thereby locking the blade in the open position. The blade further includes a release mechanism for moving the arms out of locking engagement with the blade to permit movement of the blade out of the open position.
Description




FIELD OF INVENTION




The present invention relates generally to knives, and more particularly to folding hand knives that are moved between a locked, open position and a folded position using one hand.




BACKGROUND OF THE INVENTION




It is known to provide knives that fold to a closed position and open to an in-use position using one hand. Such knives, however, are configured to operate using either only the left hand or only the right hand. A left handed knife, for example, is not operable using the right hand. Moreover, conventional, one-handed folding knives provide mechanisms for locking the knife in the extended position that are relatively easy to overcome, thereby compromising safety.




SUMMARY OF THE INVENTION




The present invention provides a releasable, double locking knife that may be operated using either the left hand or the right hand. The knife includes a body and a blade pivotally connected to the body for movement between a closed position and an open position. The body includes a pair of moveable arms that are biased toward one another into a locking position wherein the arms engage a stop surface of the blade, thereby locking the blade in the open position. Additionally, the blade carries a release mechanism that is operated by the user with the left or right thumb. When the knife is in the open position, the release mechanism is moveable toward the pair of moveable arms, and includes a pair of cam surfaces that urge the arms out of engagement with the blade, thereby permitting the blade to be folded into the closed position.











The features and advantages of the present invention described above, as well as additional features and advantages, will be readily apparent to those skilled in the art upon reference to the following description and the accompanying drawings.




BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a perspective view of a knife according to one embodiment of the present invention.





FIG. 2

is an exploded, perspective view of components of the knife shown in FIG.


1


.





FIG. 3

is a partially fragmented, perspective view of a release mechanism according to one embodiment of the present invention.





FIG. 4

is a side, elevational view of a knife according to the present invention in the open position with certain components removed for clarity.





FIG. 5

is a perspective view of the knife in FIG.


4


.





FIG. 6

is a partially fragmented, top, plan view of the knife in FIG.


1


.





FIG. 7

is a side, elevational view similar to

FIG. 4

, showing the blade of the knife moved slightly out of the open position.





FIG. 8

is a perspective view of the knife shown in FIG.


7


.





FIG. 9

is a top, plan view of the knife shown in

FIG. 8

with all components shown.





FIG. 10

is a perspective view of a knife according to the present invention shown approximately half-way between the open and the closed positions with certain components removed for clarity.





FIG. 11

is a perspective view of a knife according to the present invention in the closed position with certain components removed for clarity.





FIG. 12

is a top, plan view of the knife according to the present invention in the closed position.











DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION




The embodiments described below are merely exemplary and are not intended to limit the invention to the precise forms disclosed. Instead, the embodiments were selected for description to enable one of ordinary skill in the art to practice the invention.




Referring now to

FIG. 1

, a releasable, double locking knife according to one embodiment of the present invention is generally designated by number


10


. Knife


10


generally includes a body


12


and a blade


14


. Although this specification refers to blade


14


as a means for cutting material, it should be understood that the teachings of the present invention may be applied to a variety of different foldable tools, and is not limited to knives. For example, blade


14


may be replaced with a screw driver, a bottle opener, a cork screw, or any of a variety of other different types of tools. Body


12


generally includes a first side


16


, second side


18


, and a spacer


20


and may be formed in the shape of a handle having curved outlines as shown, or formed in any other shape for gripping when blade


14


is in the open position.




Referring now to

FIG. 2

, side


16


includes a scale


22


and a liner


24


. Scale


22


includes a recessed area


26


, and a pair of openings


28


,


30


for receiving fasteners


32


,


34


to connect side


16


to spacer


20


. Liner


24


may be shaped as shown to have an outline that corresponds substantially to the outline of scale


22


. Liner


24


includes a through hole


36


centered in a location adjacent one end of liner


24


that substantially corresponds to the center of recessed area


26


of scale


22


when liner


24


and scale


22


are connected together as will be further described below. Liner


24


further includes a pair of openings


38


,


40


that similarly correspond to the locations of openings


28


,


30


of scale


22


when liner


24


and scale


22


are connected together.




Liner


24


also includes a moveable arm, generally referred to by number


42


. In one embodiment of the invention, arm


42


is integral with and formed as a part of liner


24


. It should be understood, however, that arm


42


(and the opposed arm of side


18


) may be separate from liner


24


, but connected or otherwise coupled to liner


24


to operate in the manner described below. In the illustrated embodiment, arm


42


includes a first end


44


and a second end


46


. Second end


46


depends from liner


24


while first end


44


(or free end of moveable arm


42


) is moveable substantially into and out of a plane containing liner


24


. Thus, in this embodiment, arm


42


may be formed by cutting a slot


48


into liner


24


as shown in the drawings. As will be described in greater detail in the description of the operation of knife


10


, according to one embodiment of the present invention, arm


42


also includes an engagement surface


50


for cooperating with a portion of blade


14


to lock blade


14


in the open position, and a cam surface


51


for cooperating with a release mechanism of blade


14


to permit movement of blade


14


out of the open position.




As best shown in

FIG. 1

, arm


42


is bent or biased slightly downwardly (as viewed in the figure) relative to the plane containing liner


24


. Thus, free end


44


and engagement surface


50


are disposed, when in a relaxed or locking position, out of the plane containing liner


24


away from scale


22


. Liner


24


and arm


42


are formed, in one embodiment, of steel or other suitable material to provide strength and rigidity to body


12


, but permit some flexibility of arm


42


such that free end


44


may be moved into and out of its relaxed position.




Side


18


is essentially a mirror image of side


16


. Side


18


, generally includes a scale


52


and a liner


54


. Scale


52


, like scale


22


, includes a recessed area


56


, and a pair of openings


58


,


60


for receiving fasteners


62


,


64


. Liner


54


, like liner


24


, includes a through hole


66


, and a pair of openings


68


,


70


that are substantially aligned with recessed area


56


, and openings


58


,


60


, respectively, when liner


54


is attached to scale


52


. Liner


54


also includes a moveable arm


72


having a first end


74


(or free end) and a second end


76


that may depend from liner


54


in the manner described above with respect to arm


42


. In this embodiment, arm


72


is formed from the material forming liner


54


by providing a slot


78


as shown in the figure. Like arm


42


, arm


72


includes an engagement surface


80


and a cam surface


81


. Free end


74


of arm


72


is disposed, in its relaxed or locking position, out of a plane containing liner


54


and spaced apart from scale


52


. Accordingly, as will be further described below, when knife


10


is assembled, moveable arms


42


,


72


are biased toward one another to lock blade


14


in the open position, but may be flexed apart from one another to release blade


14


from the open position.




Spacer


20


of body


12


has a thickness “A” that substantially corresponds to the width of a cavity


82


(

FIG. 1

) formed within body


12


for receiving blade


14


when in the closed position. Spacer


20


includes a first end


84


, a second end


86


, an inner side


88


, and an outer side


90


. First end


84


and outer side


90


are curved to substantially correspond to the shape of the outlines of scales


22


,


52


, and liners


24


,


54


such that when all of the components are connected together as shown in

FIG. 1

, they form a substantially smooth profile. Inner side


88


tapers toward side


90


with distance from end


84


as shown in the figure to provide space for blade


14


when folded into the closed position and received by cavity


82


. End


86


includes an abutment surface


92


that cooperates with a surface of blade


14


to limit the pivotal movement of blade


14


when blade


14


is moved to the open position as will be further described below. Finally, spacer


20


includes two threaded openings


94


,


96


facing liner


24


and two threaded openings (not shown) facing liner


54


. Openings


94


,


96


are located to align with openings


28


,


30


of scale


22


and openings


38


,


40


of liner


24


, respectively. Scale


22


and liner


24


are connected to spacer


20


by inserting fasteners


32


,


34


through the appropriate openings in scale


22


and liner


24


, and threading fasteners


32


,


34


into threaded openings


94


,


96


of spacer


20


. The other threaded openings (not shown) of spacer


20


facing liner


54


are similarly located to receive fasteners


62


,


64


when fasteners


62


,


64


are inserted through the corresponding openings of scale


52


and liner


54


to connect scale


52


and liner


54


to spacer


20


in the manner described above.




Referring now to

FIGS. 2 and 3

, blade


14


generally includes a cutting portion


98


having a sharpened edge


100


, and a base generally referred to by the number


102


. Base


102


generally includes a first side surface


182


, a second side surface


184


, a recessed portion


104


, a wedge


108


, a thumb stud opening


110


(FIG.


1


), a pivot opening


112


, and an abutment surface


114


. As shown, recessed portion


104


is recessed into both sides


182


,


184


of base


102


to form a reduced thickness area, and includes a slot


116


for cooperating with a release mechanism


156


to release the knife


10


from its locked, open position. Wedge


108


includes a pair of stop surfaces


118


,


120


for cooperating with engagement surfaces


80


,


50


of arms


72


,


42


, respectively, to lock blade


14


in the open position, as will be further described below. It should be noted that stop surfaces


118


,


120


form a substantially obtuse angle relative to one another that substantially corresponds to an obtuse angle formed by engagement surfaces


80


,


50


when arms


72


,


42


are in the relaxed position and biased fully toward one another. Thumb stud opening


110


is situated adjacent edge


111


of base


102


, and includes a recess


122


into surface


182


, a through hole


124


, and a similar recess (not shown) into surface


184


.




Pivot opening


112


is sized to receive a pivot bearing


126


which is substantially cylindrical and has a height that is slightly greater than the thickness of base


102


of blade


14


. Pivot bearing


126


includes a central opening


128


that is sized to receive a pivot pin


130


.




Pivot pin


130


includes a shaft


132


that has a diameter that is slightly smaller than the diameter of opening


128


such that bearing


126


can pivot about shaft


132


. Pivot pin


130


also includes an enlarged diameter head


134


. Shaft


132


of pivot pin


130


is internally threaded to receive the threads


138


of a pivot screw


136


having a threaded shaft


139


and an enlarged diameter head


140


with a slot


142


for screwing pivot screw


136


into shaft


132


using a screwdriver or similar tool. As will be further described below, a pair of spacers


144


,


146


, formed in the shape of thin washers having openings with a diameter that is larger than the outer diameter of pivot bearing


126


, are positioned within body


12


to stabilize blade


14


and minimize side-to-side motion of blade


14


during use.




As also shown in

FIG. 2

, knife


10


further includes a first thumb stud


148


and a second thumb stud


150


. First thumb stud


148


is substantially cylindrical in shape and has a threaded, internal opening (not shown). First thumb stud


148


has an outer diameter that substantially corresponds to the diameter of recess


122


such that first thumb stud


148


sits within recess


122


. Second thumb stud


150


includes a threaded shaft


152


and a stud portion


154


having a diameter that substantially corresponds to the diameter of another recess (not shown), similar to recess


122


, formed in surface


184


of base


102


. Thumb studs


148


,


150


are attached to base


102


of blade


14


by inserting shaft


152


of second thumb stud


150


through thumb stub opening


110


and threading shaft


152


into the threaded, internal opening (not shown) of first thumb stud


148


. When shaft


152


of second thumb stud


150


is tightly threaded into the threaded, internal opening of first shaft


148


, first thumb stud


148


is tightly drawn into recess


122


and lateral movement of thumb studs


148


,


150


is prevented by through hole


124


and recess


122


.




Finally, knife


10


further includes a release mechanism generally referred to by the number


156


. As best shown in

FIG. 3

, release mechanism


156


generally includes an actuator


158


and a rod


160


. Actuator


158


includes a body


162


with an end tab


164


having a stop surface


166


, a ridged bearing surface


168


, a pair of cam surfaces


170


,


172


forming a wedge, and a pair of parallel tabs


174


,


176


. Tab


174


includes an opening


178


that is aligned with a similar opening


180


formed in tab


176


. Release mechanism


156


is connected to base


102


of blade


14


by positioning actuator


158


such that parallel tabs


174


,


176


fit within recessed portion


104


. The distance between the facing surfaces of parallel tabs


174


,


176


is slightly greater than the thickness of recessed portion


104


of base


102


. Accordingly, tabs


174


,


176


can move within recessed portion


104


. Actuator


158


is coupled to base


102


by inserting rod


160


through opening


178


of tab


174


, slot


116


of base


102


, and opening


180


of tab


176


. Rod


160


has an outer diameter that is slightly smaller than the width of slot


116


such that rod


160


is moveable along the length or axis of slot


116


. Rod


160


may be press fit into openings


178


,


180


or otherwise connected to tabs


174


,


176


. The path of travel of actuator


158


is substantially defined by slot


116


and the various surfaces of base


102


forming recessed portion


104


. As will be further described below, actuator


158


is thereby moveable toward and away from arms


42


,


72


along the axis of slot


116


.




Referring back to

FIG. 2

, after release mechanism


156


and thumb studs


148


,


150


are coupled to blade


14


in the manner described above, the overall assembly of knife


10


is accomplished by next inserting pivot bearing


126


into pivot opening


112


of base


102


. Pivot bearing


126


is press fit into opening


112


and because pivot bearing


126


is slightly longer than the thickness of base


102


at pivot opening


112


, the ends of pivot bearing


126


protrude slightly beyond side surfaces


182


,


184


of base


102


as best shown in FIG.


3


. The length of pivot bearing


126


is the same as thickness “A” of spacer


20


. Spacer


144


is then placed on the protruding end of pivot bearing


126


and encircles pivot bearing


126


. The thickness of spacer


144


is such that its outer surface (relative to base


102


) is flush with the end surface of pivot bearing


126


when spacer


144


is placed onto pivot bearing


126


.




Through hole


36


of liner


24


is then aligned with opening


128


of pivot bearing


126


and shaft


132


of pivot pin


130


is placed through through hole


36


and opening


128


. The partially assembled knife may then be flipped over while holding pivot pin


130


in place. Spacer


146


is then placed over the protruding end of pivot bearing


126


and through hole


66


of liner


54


is aligned with shaft


132


of pivot pin


130


. Threaded shaft


139


of pivot screw


136


is then inserted through through hole


66


, opening


128


, through hole


36


, and threaded into the threaded, internal opening (not shown) of shaft


132


. It should be understood by one skilled in the art that when pivot screw


136


is fully tightened into pivot pin


130


, blade


14


may rotate about a rotation axis (designated by the letter “B”) extending through pivot pin


130


, through hole


36


, spacer


144


, pivot bearing


126


, pivot opening


112


, spacer


146


, through hole


66


and pivot screw


136


. Moreover, the length of shaft


132


of pivot pin


130


is such that its free end is flush with the lower surface of liner


54


(as viewed in

FIG. 2

) so that when pivot screw


136


is fully threaded into shaft


132


, head


140


engages the free end of shaft


132


. This prevents pivot rod


130


and pivot screw


136


from impeding rotation of blade


14


by compressing liners


24


,


54


against spacers


144


,


146


and base


102


or against pivot bearing


126


. While blade


14


is not compressed between liners


24


,


54


, the length of shaft


132


of pivot pin


130


and the thickness of base


102


, pivot bearing


126


, and spacers


144


,


146


are such that blade


14


is prevented from wobbling side-to-side relative to liners


24


,


54


.




Spacer


20


may then be positioned between liners


24


,


54


such that the threaded openings


94


,


96


align with openings


38


,


40


of liner


24


. Scale


22


may then be placed onto liner


24


such that head


134


of pivot pin


130


is received within recessed area


26


and openings


28


,


30


align with openings


38


,


40


of liner


24


, respectively. Fasteners


32


,


34


are used to connect scale


22


to liner


24


and spacer


20


as described above. It should be understood that more than two fasteners (and corresponding openings) may be provided, or a single fastener may be used to attach the above-described components together. Also, one or more such fasteners may extend from one of scales


22


,


51


, through spacer


20


, and connect to the other of scales


22


,


52


.




The threaded openings (not shown) on the other side of spacer


20


are also aligned with openings


68


,


70


of liner


54


. Scale


52


may then be placed on liner


54


such that head


140


of pivot screw


136


is received in recessed area


56


, and openings


58


,


60


are aligned with openings


68


,


70


of liner


54


. Fasteners


62


,


64


are used to connect scale


52


to liner


54


and spacer


20


in the manner described above.





FIGS. 4-6

show knife


10


locked in an open position. For clarity, scale


22


, liner


24


, pivot rod


130


, and spacer


144


are not shown in

FIGS. 4 and 5

. When blade


14


is in the open position, moveable arms


42


,


72


extend into cavity


82


(

FIG. 6

) such that free ends


44


,


74


are in their substantially relaxed position. As best shown in

FIG. 5 and 6

, when in this position, engagement surfaces


50


,


80


of free ends


44


,


74


, contact stop surfaces


120


,


118


of wedge


108


, respectively. As best shown in

FIG. 5

, blade


14


is thereby locked in the open position and prevented from pivoting counter-clockwise (as viewed in the figures). It should be noted that further clockwise rotation of blade


14


is also prevented by engagement between abutment surface


92


of spacer


20


and abutment surface


114


of base


102


. When in this open, in-use position, blade


14


is securely locked by both inwardly biased moveable arms


42


,


72


, thereby preventing accidental closure of blade


14


into body


12


.




As is also shown in

FIGS. 4 and 5

, when blade


14


is in the open position, actuator


158


of release mechanism


156


is positioned away from arms


42


,


72


. More specifically, rod


160


is positioned within slot


116


adjacent the end of slot


116


opposite wedge


108


.




Blade


14


may be moved out of the locked, open position by first moving release mechanism


156


toward arms


42


,


72


as shown in

FIGS. 7-9

. More specifically, pressure is applied to bearing surface


168


of actuator


158


to move actuator


158


toward arms


42


,


72


through the path of travel defined by slot


116


. As actuator


158


is moved through its path of travel, rod.


160


slides through slot


116


toward the end of slot


116


adjacent wedge


108


. As best shown in

FIGS. 8 and 9

, as actuator


158


is moved toward arms


42


,


72


, cam surfaces


170


,


172


bear against cam surfaces


51


,


81


of free ends


44


,


74


. As actuator


158


is further moved in this direction, cam surfaces


170


,


172


wedge between and spread apart free ends


44


,


74


against the inward biasing force of arms


42


,


72


. When actuator


158


reaches the end of its path of travel, free ends


44


,


74


are substantially flexed out of their relaxed position by an amount sufficient to permit wedge


108


(and the remainder of base


102


) to slide between arms


42


,


72


. As best shown in

FIG. 9

, when fully urged away from one another by actuator


158


, free ends


44


,


74


are substantially planar with liners


24


,


74


, respectively, and are separated by a distance that is substantially equal to the thickness of base


102


of blade


14


. Since free ends


44


,


74


are no longer in locking engagement with stop surfaces


120


,


118


, blade


14


may be pivoted counter-clockwise (as viewed in the figures) out of the open position by applying pressure to edge


111


of blade


14


.





FIG. 10

shows blade


14


approximately half-way through its rotation about rotation axis “B” between the open position and the closed position. As blade


14


rotates, end


44


,


74


of arms


42


,


72


are urged against and ride along side surfaces


182


,


184


, respectively, of blade base


102


. Since arms


42


,


72


are flexed out of their relaxed position, the biasing force generated by the resiliency of arms


42


,


72


urges the arms against side surfaces


182


,


184


, thereby providing some resistance to the rotation of blade


14


.





FIGS. 11 and 12

show knife


10


in its closed position. As best shown in

FIG. 11

, a substantial portion of blade


14


, including sharpened edge


100


is disposed within cavity


82


. When blade


14


reaches the closed position, stop surface


166


of end tab


164


engages side


88


of spacer


20


at end


86


. This engagement prevents further rotation of blade


14


about axis “B,” and prevents sharpened edge


100


of blade


14


from engaging side


88


of spacer


20


. As shown in

FIG. 12

, free ends


44


,


74


of arms


42


,


72


remain biased against side surfaces


182


,


184


, respectively. The compressive force supplied by ends


44


,


74


retains blade


14


in the closed position. This compressive force, however, can be overcome by pushing against either thumb stud


148


or thumb stud


150


.




While holding body


12


with the palm and fingers, of one hand, the thumb of that hand is free to urge the appropriate thumb stud


148


,


150


upwardly causing rotation of blade


14


out of the closed position. In this manner, blade


14


may be rotated clockwise (as viewed in the figures) to the open position as shown in FIG.


1


. When blade


14


reaches the open position, ends


44


,


74


of arms


42


,


72


, snap inwardly toward one another to engage stop surfaces


120


,


118


, respectively, thereby locking blade


14


in the open position as described above.




The foregoing description of the invention is illustrative only, and is not intended to limit the scope of the invention to the precise terms set forth. Although the invention has been described in detail with reference to certain illustrative embodiments, variations and modifications exist within the scope and spirit of the invention as described and defined in the following claims.



Claims
  • 1. A knife including:a body; a blade pivotally connected to the body, the blade being movable between a closed position wherein the blade is positioned substantially within the body and an open position wherein the blade is positioned substantially outside the body; and a pair of movable arms disposed within the body and biased toward one another into a locking position wherein the arms lock the blade in the open position.
  • 2. The knife of claim 1 wherein the arms move into and out of the locking position by flexing.
  • 3. The knife of claim 1 wherein the arms are biased against the blade when the blade is in the closed position, thereby resisting movement of the blade out of the closed position.
  • 4. The knife of claim 1 further including a release mechanism coupled to the blade, the release mechanism including a wedge for moving the arms out of the locking position, thereby permitting movement of the blade out of the open position.
  • 5. The knife of claim 4 wherein the release mechanism is movable toward and away from the arms along a path of travel defined by the blade.
  • 6. The knife of claim 5 wherein the path of travel is defined by a slot formed in the blade.
  • 7. The knife of claim 1 wherein the body includes a pair of sides, one of the arms being connected to one of the sides, the other arm being connected to the other side.
  • 8. The knife of claim 7 wherein each of the sides includes a liner, the one arm being connected to the liner of the one side, the other arm being connected to the liner of the other side.
  • 9. The knife of claim 8 wherein the body further includes a spacer disposed between the liners to form a cavity between the liners for receiving the blade when the blade is moved to the closed position, the arms being biased into the cavity.
  • 10. The knife of claim 7 wherein the one arm is integral with the one side and the other arm is integral with the other side.
  • 11. The knife of claim 7 wherein the blade is pivotally connected to one end of each of the sides and includes a free end that is disposed adjacent another end of each of the sides when the blade is in the closed position.
  • 12. The knife of claim 11 wherein the one arm has a first end that is connected to the one side and a free end that engages a stop surface of the blade, and the other arm has a first end that is connected to the other side and a free end that engages the stop surface of the blade.
  • 13. The knife of claim 12 wherein the free end of the one arm includes an engagement surface for engaging the stop surface and the free end of the other arm includes an engagement surface for engaging the stop surface, the engagement surfaces forming a first obtuse angle when the arms are in the locking position.
  • 14. The knife of claim 13 wherein the stop surface includes a first surface for engaging the engagement surface of the one arm and a second surface for engaging the engagement surface of the other arm, the first and second surfaces forming a second obtuse angle that is substantially equal to the first obtuse angle.
  • 15. A knife including:a body defining a cavity, the body including an arm extending into the cavity; a blade connected to the body for rotation about a rotation axis between a closed position substantially within the cavity, and an opened position substantially outside the cavity wherein the arm engages the blade, thereby locking the blade in the opened position; and a release mechanism coupled to the blade for movement toward and away from the arm, the release mechanism having a cam surface for urging the arm out of engagement with the blade when the blade is in the opened position and the release mechanism is moved toward the arm; wherein the blade includes a slot adjacent the rotation axis, the release mechanism being movable along the slot.
  • 16. The knife of claim 15 wherein the release mechanism further includes a rod extending through the slot to couple the release mechanism to the blade.
  • 17. A knife including:a body defining a cavity, the body including an arm extending into the cavity; a blade connected to the body for rotation about a rotation axis between a closed position substantially within the cavity, and an opened position substantially outside the cavity wherein the arm engages the blade, thereby locking the blade in the opened position; and a release mechanism coupled to the blade for movement toward and away from the arm, the release mechanism having a cam surface for urging the arm out of engagement with the blade when the blade is in the opened position and the release mechanism is moved toward the arm; wherein the release mechanism includes a pair of substantially parallel tabs, the blade including a recessed portion defining a path of travel of the release mechanism toward and away from the arm, the recessed portion being disposed between the tabs.
  • 18. The knife of claim 17 wherein the recessed portion includes a slot for cooperating with the tabs to guide the release mechanism through the path of travel.
  • 19. The knife of claim 18 wherein the release mechanism further includes a rod extending through the slot and connected to the pair of tabs to coupled the release mechanism to the blade.
  • 20. A knife including:a body defining a cavity, the body including an arm extending into the cavity; a blade connected to the body for rotation about a rotation axis between a closed position substantially within the cavity, and an opened position substantially outside the cavity wherein the arm engages the blade, thereby locking the blade in the opened position; and a release mechanism coupled to the blade for movement toward and away from the arm, the release mechanism having a cam surface for urging the arm out of engagement with the blade when the blade is in the opened position and the release mechanism is moved toward the arm; wherein the body includes a pair of arms extending into the cavity for locking the blade in the opened position.
  • 21. The knife of claim 20 wherein the release mechanism includes a pair of cam surfaces for urging the pair of arms out of engagement with the blade when the blade is in the opened position and the release mechanism is moved toward the arms.
  • 22. The knife of claim 20 wherein the pair of arms are biased against the blade when the blade is in the closed position, thereby resisting movement of the blade out of the closed position.
  • 23. A knife including:a body having a cavity and a pair of opposed arms, each of the arms having a free end extending into the cavity; and a blade connected to the body for rotation between a closed position wherein the blade is a blade connected to the body for rotation between a closed position wherein the blade is disposed substantially within the cavity and an open position wherein the blade is disposed substantially outside the cavity, the arms engaging side surfaces of the blade when the blade is in the closed position to resist movement of the blade out of the closed position, and engaging a stop surface of the blade when the blade is in the open position, thereby locking the blade in the open position, the blade including a release mechanism for moving the arms out of locking engagement with the blade when the blade is in the open position to permit movement of the blade out of the open position.
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