Abstract:
A removable knife opening assist for a folding knife. The removable knife opening assist includes a hook and an attachment portion. The folding knife is configured to be stored in a folded condition in a container. The removable knife opening assist is configured to snag the container so that the folding knife is automatically opened for use when the folding knife is withdrawn from the container, without the need to manipulate the knife, other than the simple withdrawal of the folding knife from the container.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation-in-part of U.S. patent application Ser. No. 11/818,626 filed Jun. 15, 2007, issued as U.S. Pat. No. 8,065,804 on Nov. 29, 2011, which application was a continuation-in-part of then U.S. patent application Ser. No. 11/100,030 filed Apr. 5, 2005, now abandoned, each of which applications is incorporated herein by reference in its entirety. 
    
    
     FIELD OF THE INVENTION 
     This invention relates to folding knives, which includes folding pocket knives. 
     BACKGROUND OF THE INVENTION 
     Handheld folding knives have been used for many years for self-defense. Using a folding knife as a weapon first requires withdrawing the knife from a contained location, such as from a pocket, a sheath, a holster, or a container. The second aspect of using a folding knife as a weapon is to unfold the knife. Using a folding knife can be significantly difficult in a stressful situation, such as self-defense. Stress increases the difficulty of performing ordinary motor skills. Advanced motor skills often require extensive and dedicated training. When an individual is confronted with a situation that demands stress management and the execution of advanced motor skills, a successful outcome may be very challenging. 
     As mentioned, achieving a successful draw and unfolding of a folding knife while under stress requires training. Envision drawing a weapon while managing a physical attack. The isolated routine of a draw is now combined with a multitude of movements which severely complicate the process. Now envision the requisite skill and composure to unfold the knife. In practice, the draw and unfolding of a folding knife is measured not in seconds, but in fractions of a second. Therefore, a means for enabling the simultaneous drawing and unfolding of a folding knife will increase survivability. 
     The basic concept behind a folding knife is that it can be stored in a pocket or container. A folding knife occupies a small amount of space in one&#39;s pocket and is also safe to handle when in the folded position as the blade is securely stored in the handle. 
     Historically, folding knives have been opened with two hands (e.g., the “Swiss Army” knife) but this operation has evolved to single-handed operation. There are a number of ways to open folding knives with one hand. The most common single-hand operation is to use the thumb to engage some geometry that is designed to increase the thumb&#39;s leverage on the blade. See for example U.S. Pat. No. 4,095,337 to Pharr. These geometries come in many shapes and sizes. Some geometries are formed out of the blade itself while others are attachments which are fastened to the blade in various ways. Another single-handed operation is the wrist-flick method. This method is facilitated by reducing the blade&#39;s pivoting resistance so that a quick flick of the wrist swings the blade into an unfolded and locked position. Yet another single-handed operation of folding knives is the classic switch-blade. By depressing a release button on the knife, a retaining latch is opened, allowing a spring-loaded blade to unfold to a locked position. These methods do not meet the special needs described above. 
     Thus, there is a need for providing apparatus and procedures for modifying a conventional folding knife so that the knife may be drawn and unfolded automatically and speedily. It would be advantageous to be able to open a folding knife with the use of only one hand to draw the knife. It would be advantageous that the procedure not require any additional hand or finger manipulation of the folding knife to unfold it during removal from a container, other than gripping the knife and simply withdrawing it from a holster, pocket or other container. 
     SUMMARY OF THE INVENTION 
     The opening method of interest with the present invention uses a snagging geometry. This apparatus and method is based upon an attachment to a folding knife blade that has a geometry designed to snag a holster, pocket or other container, while the folded knife is being drawn out. As used herein, the term folding knife includes a folding knife generally, and in some embodiments, a folding pocket knife. Although the remainder of this description will use the terms “folding knife” and “folding pocket knife,” it is to be understood that a folding knife of all compatible types is contemplated. The inherent characteristic of the geometry provided in the following description automatically and speedily leverages the folding pocket knife blade open as the folding pocket knife is drawn out of the container. The snagging geometry is even capable of automatically unfolding folding pocket knives as they are withdrawn from the holster, pocket or other container using a string or lanyard attached to the end of the knife located at the opening of the holster, pocket or other container. The folding pocket knife is unfolded, even without being held in a hand or without being manipulated by a hand at all, by the simple interaction of the knife opening assist described herein with a holster, pocket or other container. No hand or finger manipulation of the folding pocket knife is required to cause it to unfold. 
     The snagging geometry preferably is oriented in the holster, pocket or other container so that, when drawn, the mechanical feature will properly engage the appropriate aspect of the holster, pocket or other container. 
     The prior art discloses snagging geometries formed as an integral part of the blade itself. See for example U.S. Pat. No. 5,878,500 to Emerson. However, nothing in the prior art provides geometries in the form of a removable attachment specifically adapted for opening the blade of a folding pocket knife by snagging a holster, pocket or other container while the knife is being drawn. 
     The purpose of the present invention is to permit a folding knife to be drawn and opened as quickly as a fixed blade knife is drawn. By attaching the knife opening assist of the present invention to a blade of a folding knife, this objective is attained. 
     According to one aspect, the invention features a removable knife opening assist for use in conjunction with a pre-existing folding knife having a blade with a sharp edge, a blade secondary edge opposite to the sharp edge, and a sharp tip, the folding knife having the blade foldably attached to a knife handle, the removable knife opening assist for use in conjunction with a pre-existing container for containing the folding knife in a folded condition. The removable knife opening assist comprises an upwardly and forwardly projecting hook; and an attachment element connected to the hook and configured to removably attach the hook to the portion of the blade secondary edge opposite to the sharp blade edge of the folding knife, the hook projecting in the direction of a front end of the attachment element, the hook configured to face toward a sharp tip of the blade of the folding knife so as to snag the holster, pocket or other container as the folding knife is being drawn out of the holster, pocket or other container for use; the removable knife opening assist configured to automatically open the folding pocket knife during removal of the folding knife from the holster, pocket or other container, and the removable knife opening assist configured to not require any manipulation of the removable knife opening assist during removal other than the simple withdrawal of the folding pocket knife from the holster, pocket or other container. In some embodiments the folding knife is used in conjunction with a clip that is provided so that the folding knife is properly oriented in the holster, pocket or other container. 
     In one embodiment, the attachment element comprises at least one screw. 
     In another embodiment, the attachment element comprises at least one spring enabled latch. 
     In yet another embodiment, the attachment element comprises at least one removable pin. 
     In still another embodiment, the attachment element comprises one threaded stud. 
     In a further embodiment, the removable knife opening assist further comprises an alignment portion having a channel formed therein, the channel configured to position the alignment portion over a portion of the blade secondary edge opposite to a sharp blade edge of the folding knife; the alignment portion connected to the hook and to the attachment portion. 
     In yet a further embodiment, the attachment element comprises a threaded attachment element. 
     In an additional embodiment, the attachment element comprises a clip attachment element. 
     The present invention provides a knife opening assist which is removably attached to any existing folding knife blade. The assist is comprised of an attachment element with a channel formed therein for positioning over a portion of any blade edge opposite to a sharp blade edge. The attachment element is attached to the blade by an attachment portion in the element. The top of the attachment element has a hook-shaped element hooking toward the forward end of the blade, the hook adapted to snag a pocket, holster or other container as the pocket knife is being drawn out for use. 
     The foregoing and other objects, aspects, features, and advantages of the invention will become more apparent from the following description and from the claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The objects and features of the invention can be better understood with reference to the drawings described below, and the claims. The drawings are not necessarily to scale, emphasis instead generally being placed upon illustrating the principles of the invention. In the drawings, like numerals are used to indicate like parts throughout the various views. 
         FIG. 1  is a side perspective view of a folding knife in a closed position. 
         FIG. 2  is a side perspective view of the knife of  FIG. 1  in an open position. 
         FIG. 3  is a bottom view of the knife of  FIG. 2 . 
         FIG. 4  is a side perspective view of a studded blade. 
         FIG. 5  is a side perspective view of a blade with a larger aperture. 
         FIG. 6  is a side perspective view of a slotted blade. 
         FIG. 7  is a side view of the knife of  FIG. 2  with a knife opening assist. 
         FIG. 8  is a side perspective view of the knife opening assist mounted on a blade. 
         FIG. 9  is a side view of a knife opening assist mounted on a blade. 
         FIG. 10  is a front view thereof. 
         FIG. 11  is an elevational side view of a knife opening assist. 
         FIG. 12  is a side perspective view of the invention with a threaded aperture. 
         FIG. 13  is a side perspective view of the invention with a smooth aperture. 
         FIG. 14A  is a side view of another embodiment of the invention. 
         FIG. 14B  is a cross sectional view of the assist shown in  FIG. 14A . 
         FIG. 14C  is a side view of the assist shown in  FIG. 14A . 
         FIG. 14D  is a side perspective view of an insert used in  FIG. 14A . 
         FIG. 14E  is a side view of the insert positioned in a blade aperture. 
         FIG. 15A  is a front view of an assist with bottom clip. 
         FIG. 15B  is a front perspective view of an assist with a bottom clip. 
         FIGS. 16A-16C  are side views of assists with varying hook profiles. 
         FIG. 17  is a cutaway side view of a knife and container according to one embodiment of the invention. 
         FIGS. 18A-18E  are cutaway side views of a knife and container in various stages of withdrawal according to one embodiment of the invention. 
         FIG. 19A  is a diagram of a screw attachment in which the knife opening assist is mounted to one or more machined holes in the blade&#39;s secondary edge. 
         FIG. 19B  is a diagram of a screw attachment in which the knife opening assist is mounted to one or more machined holes in the side of the blade. 
         FIG. 19C  is a diagram of at least one spring enabled latch on an end of the knife opening assist which is then mounted in a knife slot. The knife opening assist is slid in from the side while depressing the one or more latches. When the knife opening assist is inserted completely, the one or more latches spring up into the chambers. To remove the knife opening assist, a pin is pushed into each pin hole compressing the respective spring-loaded latch while the knife opening assist is slid sideways and out. 
         FIG. 19D  is a diagram of a tension pin attachment where the knife opening assist is inserted into a cavity of the knife. One or more removable tension pins are then driven into one or more matched holes in the knife and the knife opening assist. To remove the knife opening assist, the one or more removable tension pins are driven out of the respective one or more holes. 
         FIG. 19E  is a diagram of a threaded stud which is part of the knife opening assist and is screwed into a threaded hole of the knife. To remove the knife opening assist, the knife opening assist is unscrewed from the threaded hole. Temporary threadlock adhesive or other thread locking methods can be used to assure alignment of the knife opening assist. 
         FIG. 20A  is a side view of a folding pocket knife having a clip on one side as the folding pocket knife is being withdrawn from a container. 
         FIG. 20B  is an exploded view of the clip and one method of using screws to attach the clip to the handle of the folding pocket knife. 
     
    
    
     DETAILED DESCRIPTION 
     Referring to the drawings in detail wherein like elements are indicated by like numerals, there is shown in  FIGS. 1-3  a typical folding knife  1  comprised of a handle  10  and a blade  20  pivotally connected to said handle  10 . The handle  10  has a forward end  11 , a rear end  12 , an elongated body  13  interconnecting said front and rear ends, said elongated body having two opposite sides  14 , a top  15  and a bottom  16 , said bottom having an elongated cavity  17  extending from said forward end  11  near to said rear end  12 . The handle forward end  11  and rear end  12  define a handle longitudinal axis. The blade  20  has a primary cutting edge  21 , a secondary edge  22 , two opposite, generally flat sides  23 , a forward end portion  24  terminating in a tip  25 , and a rear end portion  26 , said forward end and rear end portions defining a blade longitudinal axis. The blade rear end portion  26  has a first aperture  27  formed therein. The blade  20  is rotatably interconnected to the forward end  11  of the handle by means of a pin  18  through the handle sides  14  near to the handle forward end  11 , said pin  18  engaging the blade rear portion first aperture  27 . 
     The knife  1  has an open position, wherein the blade  20  is in a first extended position of use and having its longitudinal axis positioned substantially co-extensive with the handle longitudinal axis. The knife  1  has a closed position wherein the blade  20  is pivoted rearward about the pin  18  with the blade cutting edge  21  substantially inserted into said handle elongated cavity  17 , said blade longitudinal axis and handle longitudinal axis having a substantially parallel relationship. 
     In various embodiments of folding knives, the knife blade  20  may be modified near to its rear end portion  26 .  FIG. 2  illustrates a plain knife blade  20 .  FIG. 4  illustrates a knife blade  20  with a stud assembly  200  attached to said blade  20  near to the blade rear end portion  26 . The stud assembly  200  is attached to the blade  20  through a smooth second aperture  201  formed through the blade sides  23 . The stud assembly  200  may be comprised of a stud bolt  202  threadingly engaged through the smooth second aperture  201  with a stud nut  203 . As may be seen in  FIG. 5  some blades will have a second aperture  205  formed near to the blade rear end portion  26 . As may be seen in  FIG. 6 , other blade sides may have an elongated groove  207  running longitudinally adjacent to the secondary edge  22 . The assist  30  of the present invention is designed to work with knife blades which are smooth, which have studs  200 , which have a second aperture  205 , which have elongated side grooves  207 , or any combination of the above. 
     Referring to the remaining drawings, the knife opening assist  30  is removably attached to the knife blade  20 . The assist  30  is comprised of an attachment element  31  with a channel  32  formed therein for positioning over a portion of the blade secondary edge  22 . The attachment element  31  has a top  33 , a bottom  34 , a front end  35 , a rear end  36 , and two opposite sides  37 . The channel  32  is formed in the element bottom  34  extending from front end  35  to rear end  36 , said front end and rear end defining a channel longitudinal axis. Each side  37  has an aperture  38  formed therein, each said aperture  38  opening into said channel  32 . The aperture  38  may be threaded as shown in  FIG. 12  or smooth as shown in  FIG. 13 . The attachment element top  33  is formed into the shape of an upwardly and forwardly projecting hook  40 , said hook projecting in the direction of the attachment element front end  35 . The hook may have various shapes, e.g., height, length, contour, for specific uses.  FIG. 9  illustrates a hook  40  with a classic shape.  FIGS. 16A-16C  illustrate hooks  40  with other contour variations. The hook  40  is adapted to snag a pocket, holster or other container as the folding knife  1  is being drawn out for use, thereby pivotally pulling the blade  20  out of the cavity  17 . 
       FIG. 17  shows an exemplary knife  1  being withdrawn from a container  5 .  FIGS. 18A-18E  show an exemplary folding knife  1  with a hook  40  in various stages of withdrawal from a container  5 . As shown the hook  5  is adapted to snag a container lip  6  or edge as the folding knife  1  is being drawn out for use, thereby pivotally pulling the blade  20  out of a cavity  17  in the knife handle  10 . The container  5  may be a clothing pocket or a holster. 
     The assist  30  is further comprised of means for attaching the assist  30  to blade  20 . In one embodiment of the invention, the attachment means is comprised of a threaded lockable set screw  39  threadingly engaging each threaded aperture  38 . See  FIGS. 9 and 12 . The assist  30  is positioned onto the blade secondary edge  22 , wherein the attachment element channel  32  fits over the blade secondary edge  22 , said attachment element sides  37  overlapping a portion of the blade sides  23 . The attachment element front end  35  faces the blade forward end portion  24  and said attachment element rear end  36  faces the blade rear end portion  26 . Where the blade sides  23  are solid, the assist  30  is used with two threaded lockable set screws  39 , one for each attachment element aperture  38 . The screws  39  hold the assist  30  in place on the blade  20 . 
     Where a studded knife blade  20  as shown in  FIG. 4  is provided, the assist  30  of  FIGS. 8 and 13  are used, said assist having smooth bore apertures  38  adapted for use in conjunction with the stud assembly  200 . The assist apertures  38  are aligned with the blade second aperture  201 . The stud bolt  202  and stud nut  203  are threadingly joined through the smooth assist apertures  38  and blade second aperture  201 . See  FIG. 13 . 
     Where there is a blade second aperture  201  or  205 , such as shown in  FIGS. 4 and 5 , one long lockable bolt or set screw  210  may be used, said bolt  210  extending from one element aperture  38 , through the blade second aperture  201  or  205 , and into the opposite element aperture  38 . The assist apertures  38  may be designed so that one aperture  38  is smooth and countersunk for accommodating the bolt head  211 . The opposite aperture  38 ′ may be threaded to threadingly engage the bolt threads  212 . See  FIGS. 14A-C . 
     In another embodiment of the invention, an assist insert  45  having the general circumferential shape of the blade second aperture  205  may be used. See  FIGS. 14D and 14E . The insert  45  has an aperture  46  having a central axis concentric with the assist apertures  38 ,  38 ′. The insert aperture  46  accommodates a threaded lockable long bolt or set screw  210  which goes through smooth apertures  38  and  46  and engages the opposite assist threaded aperture  38 ′. See  FIG. 14A . 
     In still another embodiment, the assist bottom  34  may be formed into a clip shape adapted to grasp a blade second aperture upper edge  206 . See  FIGS. 15A and 15B . 
     The present invention adds a knife opening assist  30  enabling the simultaneous drawing and opening of a folded knife during a weapon&#39;s draw, resulting in a one-step weapon draw. The assist attachment hook-shaped element  40 , oriented toward the forward end of the blade, is adapted to snag a pocket, holster or other container as the folding knife is being drawn out for use. The assist  30  thereby draws the blade  20  out of the handle cavity  17  as the knife is being drawn from its container, i.e., pocket or holster. 
       FIG. 20A  shows one method used to orient the folding pocket knife so that the knife opening assist will properly engage the holster, pocket or other container. The pocket  5  is that of a right upper-thigh trouser pocket for use with a right handed draw. The clip  70  is placed exterior to the pocket while the knife handle  10  is placed interior. In this orientation, the knife opening assist  40  is located rear toward the trouser buttocks region. The blade pivot pin  18  is located downward in the pocket, opposite to the clip  70  attachment point. The blade tip  25  is located upward of the pocket relatively adjacent to the clip  70  attachment point. Notice that the knife opening assist  40  is attached to the blade&#39;s secondary edge  22 . 
     In additional embodiments, the knife opening assist is a removable attachment to the knife blade. Its construction will vary based on the method of attachment. Ultimately there are many ways to attach the assist. Knife opening assists with a channel have already been displayed and discussed. We now describe alternative systems and methods of attachment of the knife opening assist, systems and methods which do not use a channel in the knife opening assist. These alternative constructions and methods of assembly are illustrated in  FIG. 19A  through  FIG. 19E . In each figure, a side elevation view of the knife opening assist as assembled to a knife blade is illustrated on the left side of each figure, an exploded view of the knife opening assist that illustrates the parts thereof is shown in the center of each figure, and a top view of the knife opening assist as assembled to a knife blade is illustrated on the right side of each figure. 
     Furthermore knife opening assists can be retrofitted to existing or conventional knives (that is, to knives which were not designed with the original intent of utilizing a removable knife opening assist) or they may be fitted to custom knives (that is, to knives which are designed for specific use with the removable knife opening assist). 
     Any patent, patent application, or publication identified in the specification is hereby incorporated by reference herein in its entirety. Any material, or portion thereof, that is said to be incorporated by reference herein, but which conflicts with existing definitions, statements, or other disclosure material explicitly set forth herein is only incorporated to the extent that no conflict arises between that incorporated material and the present disclosure material. In the event of a conflict, the conflict is to be resolved in favor of the present disclosure as the preferred disclosure. 
     While the present invention has been particularly shown and described with reference to the preferred mode as illustrated in the drawing, it will be understood by one skilled in the art that various changes in detail may be affected therein without departing from the spirit and scope of the invention as defined by the claims.