Patent Application
20060277762
The present invention generally relates to hand tools, and in particular to tools wherein a cutting implement may be folded into a handle for improved storability and improved safety.
Folding knives, or so-called pocket knives, have been around for over a hundred years and are well known in the art. Initially, folding knives were a single blade housed between two handle portions and rotatable around a pivot point such as a screw or rivet at one end of the handle. During use, the blade is rotated approximately 180 degrees such that the blade extends from the handle and the blade and handle share a common longitudinal plane. The handle and tang end of the blade come in contact to prevent the blade from over-rotating and to provide a solid cutting implement. For storage, the blade is rotated the opposite direction the same approximate 180 degrees, and stored in a cavity within the handle. With the blade stored, the overall length of the knife is approximately 40% shorter, thereby allowing for convenient storage in, for example, a pocket. The small size of such a knife makes it desirable as a portable and efficient means of having a cutting implement available at all times.
Over time, many improvements have been made to the basic pocket knife premise to improve both function and aesthetics. For example, one or more additional blades have been added to provide options for blade shape, size, and utility. Additionally, other implements and tools have been added, up to and including eating utensils, flashlights, cork screws, screwdrivers, lanyards, scissors, and a seemingly endless myriad of other useful tools. As one might expect however, the addition of tools adds to the overall size of the folding knife, thereby decreasing the ease of storage, and potentially the desirability of carrying the knife in the first place. The result is a give-and-take analysis where one must prioritize the function and use frequency of each potential tool, and then weigh that against the physical size of the tool and how it will be carried by the user. This general development has also led to other useful items incorporating a folding knife blade into them. For example, carabiners, flashlights, key chains, etc. have been modified to have a blade contained somewhere within their respective frames.
Another general area of improvement has been in the opening of the knife blade. Originally, the blade had a recess cut into the side of the blade where a fingernail could catch and extract the blade from its stored position. The need and/or desire for the ability to open a blade using only one hand spurred a number of competing modifications, such as a thumb stud mounted on the side of the blade, a portion of the blade tang protruding out of the handle, or even a button released spring-assisted opening mechanism. Some of these mechanisms that exert stored potential energy on the blade and eject the blade from the storage cavity at high speed have been classified as illegal weapons and subsequently outlawed in some, but not all, jurisdictions. This causes considerable problems for a person who may legally carry such a knife in his own jurisdiction, and therefore without thinking carries it into another jurisdiction where it has been outlawed. One common feature though, is the placement of a release button or operating lever for a blade-opening device. Traditional placement of such mechanisms has been on the side of the blade or on the side of the handle, enlarging the tool and potentially providing a point where clothing or other items can be snagged or caught on the mechanism.
Although there are many options in the folding knife technology area, there is an ongoing desire to improve space efficiency and use of such knives. What is desired then, is an improved knife that maximizes space utilization, and that provides a mechanism for easily opening a blade with one hand while minimizing the size of the mechanism and optimizing its location.
The present invention addresses the previously mentioned shortcomings of the prior art and addresses the aforementioned desired features by providing a folding tool including improvements in space utilization such that a blade and an additional tool can share the same blade cavity in a coaxial or coplanar fashion, without causing the knife to be substantially longer than a single-blade knife of similar size and shape.
In a folding tool including an embodiment of one aspect of the invention, a carabiner lies generally coplanar with a blade. A portion of the carabiner defines a slot along the longitudinal axis in such a way that the blade can rest within the slot. In this embodiment, the carabiner rotates around one end pivot and exits the blade cavity from the top of the blade cavity, and the knife blade rotates around a pivot axis at the other end of the tool and exits from the bottom of the blade cavity such that both the knife blade and the carabiner rotate in the same direction relative to the tool handle to open from the handle (i.e. both rotate clockwise rather than one rotating clockwise and the other rotating counter-clockwise). This configuration allows for the independent opening of each of the blade and carabiner such that both the blade and the carabiner may be stored, either one of them stored and the other opened, or both may be opened at the same time. Furthermore, the opening and closing of each is completely independent of, and has no effect whatsoever on the other.
In an alternative tool which is an embodiment of an aspect of the invention, a carabiner again lies generally coplanar with a blade. In this embodiment, however, the carabiner enters and exits the blade cavity at one end of the handle by sliding along the longitudinal axis of the handle. When the carabiner is slid into the blade cavity, a gate of the carabiner is forced into the retracted or open position, and the end of the knife blade occupies space created by retracting the carabiner gate. The knife blade exits the blade cavity by rotating around a pivot at the other end of the knife handle. Again, although the carabiner and the knife blade share space in the blade cavity, each may be deployed or stored without any effect on the other.
In yet another folding tool which is an embodiment of an aspect of the invention, an open-assist flipper is utilized to provide a novel method of opening the blade with one hand. The open-assist flipper is placed at the end of the knife and is completely, or almost completely, housed within the blade cavity. The open-assist flipper has a finger stud that sticks out toward the end of the knife in the gap between the two sides of the handle, and rotates around the same pivot axis as the knife blade, but the flipper is not mechanically linked to the knife blade. Rather, by rotating the finger stud around the pivot point, a flange on the open-assist flipper body is made to contact the tang end of the blade at the blade kick, causing the blade to rotate out of the cavity. Since the open-assist flipper is not attached to the blade, it can be rotated back to its original position thereafter without causing the blade to be returned to the knife cavity. It also provides some controlled play such that if the lever gets snagged on an article of clothing or the like, it can rotate around the pivot point a certain amount without causing the blade to be deployed.
Other embodiments exist where more than one set of coplanar tools is desired. One such embodiment includes a coplanar knife blade and carabiner as explained above, coupled with another set of coplanar tools such as, for example, a can opener and a bit driver. In this embodiment, additional bits are stored in a recess in one handle of the knife. The bit driver and bits are designed to have a thin profile similar to the thickness of the blade used, yet still provide useful tools such as a four-bladed #2 Phillips head screwdriver; a tool typically not associated with such a thin structure. It is even conceivable that the various embodiments may be utilized with a folding tool that only has one elongate handle half as opposed to two handle halves by simple modifications.
The foregoing few embodiments mentioned out of the many possible embodiments available, along with other objectives, features, and advantages of the invention will be more readily understood and appreciated upon consideration of the following detailed description taken in conjunction with the accompanying drawings.
Referring now to the drawing figures, wherein like reference numerals represent like parts throughout the several figures,
When assembled, the folding tool 8, including scales 10 and 20, bolsters 16 and 18, frames 40 and 42, open-assist flipper 60, blade 50, carabiner 70, liner plate 90, bit driver 110, and spacer 120 are secured by mated blade fasteners 24 and 28 at one end and by similar fasteners 22 and 30 at the other end. Blade fasteners 28 and 30 also act as pivots for the open-assist flipper 60, the knife blade 50, the carabiner 70, and the bit driver 110.
The handle thus has a pair of opposite first and second ends, a top margin 34 and a bottom margin 36. In the embodiment shown, spacer 120 does not rotate about blade fastener 30, but in other embodiments not shown the spacer 120 could be replaced with other useful tools such as a can opener, screw driver, blade, file, saw, scissors, awl, punch, or tweezers, that would then rotate about blade fastener 30. It should be equally obvious that bit driver 110 could be replaced with any such tool, thus giving almost limitless options and permutations of various tools as desired.
A spring 100, fixedly attached to liner plate 90 by a fastener 92 such as a rivet, screw, brad, detent, or other such means, provides a biasing force on the bit driver 110, biasing it toward either the closed position or the open position depending on the rotational location of the bit driver 110, such that it urges a closed driver to stay closed, and an open driver to stay open.
A carabiner 70 is located between liner plate 90 and frame 40, and is pivotally mounted on and rotatable around blade fastener 30. As shown in
The carabiner 70 may optionally contain a mechanism (not shown) to hold the gate 74 open as needed, so that the carabiner could be used as a hook rather than a secured locking mechanism. Additionally, when the carabiner 70 is in the fully opened position it may be used to open a bottle. When the carabiner frame 80 is placed over a bottle cap the spring gate 74 rotates open allowing the end 86 of the frame 80 to hook under the flanges of a crimped bottle cap. The gate base portion 88 of carabiner 70 then acts as a fulcrum for prying the cap from the bottle.
On the end of the tool 8 opposite the carabiner 70, an open-assist flipper 60 is provided, as shown in
Optionally, the open-assist flipper 60 may contain a spring mechanism (not shown) to assist in opening the blade more quickly. In such a case, the spring may be located between the blade kick 56 and the flange 64, or may be an integral part of the flipper itself. The spring may be in the form of a coil spring, a leaf spring, a resiliently deformable material, or other spring mechanisms known in the art. In the case when a spring assist is used, an interlock, blade detent, or some other form of resistance known in the art, retains the blade in the closed position, and only when sufficient force is applied to the flipper 60 and thus the spring mechanism to overcome the resistance will the blade 50 open. This resistance can obviously be designed to be as small or as large as desired. It is important to note that if a spring mechanism is employed in such a manner, because of the rotational freedom of the open-assist flipper 60 to move away from the blade kick 56, there would normally be effectively no stored potential energy held by the spring, unless the open-assist flipper is being urged to open the blade 50. This is important as a safety feature, because the knife blade 50 thus would not spring open accidentally. Such an arrangement of the spring also would exclude the knife from the definition of a switchblade, since there is no “release mechanism” whereby stored potential energy is released, causing the blade to open. Nevertheless, along the lines of a standard switchblade, the open-assist flipper 60 could optionally contain a blade lock arranged in such a way that when the flipper is rotated to a certain location, a lock mechanism physically prevents the blade from being opened, adding another degree of safety.
The blade 50 may also have a standard opening feature such as a thumb stud 52, or other devices commonly used such as a nail groove or the like. The open-assist flipper 60 will not interfere with or restrict the use of these other methods of opening the knife blade. The blade 50 may also have a lock mechanism, such as the liner lock wherein the outer end of the liner lock spring 94 engages the kick 56 and holds the blade 50 firmly in the open position until the liner lock spring 94 is released, allowing the blade 50 to return to the closed position. Optionally, the open-assist flipper 60 may incorporate another mechanism (not shown) that could release the liner lock 94 when the flipper 60 is rotated, allowing the blade to be closed. Although a liner lock 94 is shown, other lock mechanisms known in the art may be utilized in conjunction with the open-assist flipper 60. It should also be noted that this embodiment discloses the use of the open-assist flipper 60 on the blade 50, but such an open-assist flipper 60 may be used to open any tool selected to be incorporated into the knife. Similarly, multiple flippers may be utilized within one folding tool 8, so that up to each blade or bit of the tool may have its own flipper. In this instance, the multiple flippers may be staggered or a selection device may be utilized such that one flipper can open any one of the tools, as selected by the user.
Referring now to
A gate retractor 146 also lies substantially co-planar with both the knife blade 50 and the gate 142. The gate retractor 146 is a body mounted on the liner plate 134 in line with the gate 142 and in position to act as a cam that serves as a brace to hold the gate 142 open when the carabiner 138 is partially or fully retracted, as shown in
As shown in
As shown in
As may be seen best in
While the invention has been described in some embodiments, it should be readily apparent to those skilled in the art that many modifications, additions, and deletions may be made therein without departing from the spirit and scope of the invention. For example, each of the two general embodiments disclosed not only incorporate a blade and carabiner sharing a same blade cavity, but each has a secondary cavity containing one or more additional tools. These additional tools and additional blade cavity can be eliminated, or even more additional blade cavities can be added. Similarly, the novel features may be interchanged as desired, as by the open-assist mechanism being included in the same tool with the sliding carabiner. The invention is therefore not intended to be limited by the explicitly disclosed embodiments, but rather by the appended claims.
