BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a conventional folding knife in its fully extended position with the blade detached from the tang;
FIG. 2 is a perspective view of a first preferred embodiment of folding knife according to the invention in its fully extended position;
FIG. 3 is an exploded view of the folding knife of FIG. 2;
FIG. 4 is an exploded view of a second preferred embodiment of folding knife according to the invention;
FIG. 5 is an exploded view of a third preferred embodiment of folding knife according to the invention; and
FIG. 6 is an exploded view of a fourth preferred embodiment of folding knife according to the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 2, a folding knife in accordance with a first preferred embodiment of the invention comprises a blade 3, a tang 2, and a handle 1. Each component is discussed in detailed below.
The tang 2 comprises two elongate pieces 21 of substantially rectangular in shape, a plurality of fasteners 22 for fastening the pieces 21 together, and a front parallelogram cavity 23 provided in one piece 21 for anchoring a rear end of the blade 3 as detailed later. Rear portions of the pieces 21 are pivotably secured to a front end of the handle 1 by means of a pin 12. Thus, both the tang 2 and the blade 3 can pivotably either receive in a lengthwise, central slot 11 of the handle 1 when not in use or extend out of the slot 11 for use.
Referring to FIG. 3 in conjunction with FIG. 2, the cavity 23 is defined between and by the pieces 21 when the pieces 21 are fastened together. An L-shaped flexible tongue 24 is extended from a rear end of the other piece 21. The tongue 24 has its front portion corresponding to the cavity 23. A substantially U-shaped push member 25 is provided on a recessed top edge at a front portion of one piece 21. The tongue 24 comprises a circular projection 241 on its inner surface. For mounting the blade 3, a user may first slide the push member 25 rearward to push the open end of the tongue 24 away from the cavity 23. Then insert the blade 3 into the cavity 23 until a rear, circular through hole 31 of the blade 3 lines up with the projection 241. Next, slide the push member 25 forward. The projection 241 automatically bounces back into the through hole 31 for fastening the blade 3 in the cavity 23 due to the flexibility of the tongue 24. As a result, the blade 3 and the tang 2 are secured together. To the contrary, for detaching the blade 3 from the tang 2, a user may first slide the push member 25 rearward to push the open end of the tongue 24 away from the cavity 23. Also, the projection 241 clears the through hole 31. As such, the blade 3 is not fastened in the cavity 23. As a result, the user may remove the blade 3 out of the tang 2 for replacement. By configuring the tongue 24 as an integral part of the other piece 21 of the tang 2, materials and manufacturing cost are greatly reduced, assembly steps are significantly decreased, and the tongue 24 is fully protected.
Referring to FIGS. 2 and 3 again, in the first preferred embodiment of the invention the rear end of the tongue 24 is integrally formed with the other piece 21 proximate the front end of the handle 1 and the front end thereof is extended away from the front end of the handle 1. The tongue 24 further comprises a trapezoidal latch 242 at its open end. The latch 242 has a short front side and a long rear side (i.e., tapered from the handle 1 toward the blade 3). The U-shaped push member 25 is slidably provided on a recessed top edge at a front portion of one piece 21. The latch 242 is partially disposed in the opening of the push member 25. That is, a corner of the front side of the latch 242 proximate the rear end of the blade 3 engages with the opening of the push member 25. Thus, for detaching the blade 3 from the tang 2 a user slides the push member 25 rearward to push the open end of the tongue 24 away from the cavity 23 by sliding the push member 25 along the inclined side of the latch 242 and the projection 241 thus clears the through hole 31. As such, the blade 3 is not fastened in the cavity 23. Therefore, the user may remove the blade 3 out of the tang 2 for replacement. To the contrary, after disposing the blade 3 in the cavity 23 a user may slide the push member 25 forward. The projection 241 automatically bounces back into the through hole 31 for fastening the blade 3 in the cavity 23 due to the flexibility of the tongue 24. As a result, the blade 3 and the tang 2 are secured together.
Referring to FIG. 4 in conjunction with FIG. 2, a second preferred embodiment of the invention is illustrated. The rear end of the tongue 24 is integrally formed with the other piece 21 proximate the front end of the handle 1 and the front end thereof is extended away from the front end of the handle 1. The tongue 24 comprises a rectangular protrusion 243 at its open end. One end of the flexible push member 25 is integrally formed with one piece 21 and the other end thereof is bent to form as a rectangular latch 251 facing the protrusion 243. Also, the push member 25 is adapted to slightly flex toward the protrusion 243. Further, the latch 251 bears on a top of the protrusion 243. In one operation, a user may push the open end of the push member 25 toward the open end of the tongue 24. Thus, the latch 251 presses the protrusion 243 to move the open end of the tongue 24 out of the cavity 23 until the projection 241 clears one of a plurality of recesses 31 of the blade 3. As such, the blade 3 is not fastened in the cavity 23. Therefore, the user may remove the blade 3 out of the tang 2 for replacement. To the contrary, after disposing the blade 3 in the cavity 23, the projection 241 automatically bounces back into the through hole recess 31 without manipulating the latch 251 for fastening the blade 3 in the cavity 23 due to the flexibility of the tongue 24. Also, the open end of the push member 25 returns to its original position. As a result, the blade 3 and the tang 2 are secured together.
Referring to FIG. 5 in conjunction with FIG. 2, a third preferred embodiment of the invention is illustrated. One end of the flexible tongue 24 is integrally formed with the other piece 21 distal the front end of the handle 1 and the other open end thereof is bent to form a trapezoidal latch 242. The latch 242 has a short front side and a long rear side (i.e., tapered from the handle 1 toward the blade 3). The U-shaped push member 25 is slidably provided on a recessed top edge at a front portion of one piece 21. The latch 242 is partially disposed in the opening of the push member 25. That is, a corner of the front side of the latch 242 proximate the rear end of the blade 3 engages with the opening of the push member 25. Thus, for detaching the blade 3 from the tang 2 a user slides the push member 25 rearward to push the open end of the tongue 24 away from the cavity 23 by sliding the push member 25 along the inclined side of the latch 242 and the projection 241 thus clears the through hole 31. As such, the blade 3 is not fastened in the cavity 23. Therefore, the user may remove the blade 3 out of the tang 2 for replacement.
Referring to FIG. 6 in conjunction with FIG. 2, a fourth preferred embodiment of the invention is illustrated. One end of the flexible tongue 24 is integrally formed with the other piece 21 distal the front end of the handle 1 and the other open end thereof is extended to form a rectangular protrusion 243. One end of the flexible push member 25 is integrally formed with one piece 21 and the other end thereof is bent to form as a rectangular latch 251 facing the protrusion 243. Also, the push member 25 is adapted to slightly flex toward the protrusion 243. Further, the latch 251 bears on a top of the protrusion 243. In one operation, a user may push the open end of the push member 25 toward the open end of the tongue 24. Thus, the latch 251 presses the protrusion 243 to move the open end of the tongue 24 out of the cavity 23 until the projection 241 clears one of a plurality of recesses 31 of the blade 3. As such, the blade 3 is not fastened in the cavity 23. Therefore, the user may remove the blade 3 out of the tang 2 for replacement.
The blade 3 and the tang 2 in each of the preferred embodiments of the invention may be embodied as below. As shown in FIGS. 3 and 5, the through hole 31 is formed on the rear end of the blade 3 and is circular. A second through hole 211 is formed on the cavity 23. The through hole 31 is adapted to line up with the second through hole 211 when the blade 3 is mounted in the cavity 23. Further, the second through hole 211 is shaped the same as the through hole 31. That is, both of the through holes 211 and 31 have a circular shape. Furthermore, both the projection 241 and the through hole 31 are shaped the same. That is, both of the projection 241 and the through hole 31 have a circular shape. After disposing the rear end of the blade 3 in the cavity 23, the projection 241 automatically bounces back through the through hole 31 into the second through hole 211 for fastening the blade 3 in the cavity 23 by lockingly engaging the projection 241 in the second through hole 211 due to the flexibility of the tongue 24.
The blade 3 and the tang 2 in each of the preferred embodiments of the invention may be alternatively embodied as below. As shown in FIGS. 4 and 6, a plurality of elongate, slanted, parallel recesses 31 are formed a top edge of on the blade 3. The recesses 31 have an open top end and an arcuate, closed bottom end. A slanted, elliptic through hole 211 is formed on the cavity 23 and is disposed corresponding to the slanted, elliptic projection 241. After disposing the rear end of the blade 3 in the cavity 23, the projection 241 automatically bounces back through one of the recesses 31 into the through hole 211 for fastening the blade 3 in the cavity 23 by lockingly engaging the projection 241 in the through hole 211 due to the flexibility of the tongue 24.
While the invention herein disclosed has been described by means of specific embodiments, numerous modifications and variations could be made thereto by those skilled in the art without departing from the scope and spirit of the invention set forth in the claims.
Patent Application
20080052913
