EP0271223A1 - Retractable blade knife - Google Patents
Retractable blade knife Download PDFInfo
- Publication number
- EP0271223A1 EP0271223A1 EP87309976A EP87309976A EP0271223A1 EP 0271223 A1 EP0271223 A1 EP 0271223A1 EP 87309976 A EP87309976 A EP 87309976A EP 87309976 A EP87309976 A EP 87309976A EP 0271223 A1 EP0271223 A1 EP 0271223A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- blade
- carrier
- handle
- sharpener
- knife according
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 238000010276 construction Methods 0.000 description 12
- 230000002441 reversible effect Effects 0.000 description 2
- 238000007792 addition Methods 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- 230000000295 complement effect Effects 0.000 description 1
- 230000003750 conditioning effect Effects 0.000 description 1
- 230000000994 depressogenic effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000000717 retained effect Effects 0.000 description 1
- UONOETXJSWQNOL-UHFFFAOYSA-N tungsten carbide Chemical compound [W+]#[C-] UONOETXJSWQNOL-UHFFFAOYSA-N 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B26—HAND CUTTING TOOLS; CUTTING; SEVERING
- B26B—HAND-HELD CUTTING TOOLS NOT OTHERWISE PROVIDED FOR
- B26B5/00—Hand knives with one or more detachable blades
- B26B5/001—Hand knives with one or more detachable blades with blades being slid out of handle immediately prior to use
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24D—TOOLS FOR GRINDING, BUFFING OR SHARPENING
- B24D15/00—Hand tools or other devices for non-rotary grinding, polishing, or stropping
- B24D15/06—Hand tools or other devices for non-rotary grinding, polishing, or stropping specially designed for sharpening cutting edges
- B24D15/08—Hand tools or other devices for non-rotary grinding, polishing, or stropping specially designed for sharpening cutting edges of knives; of razors
- B24D15/084—Hand tools or other devices for non-rotary grinding, polishing, or stropping specially designed for sharpening cutting edges of knives; of razors the sharpening elements being fitted to knife sheaths, holders or handles
Definitions
- This invention relates to knives of the kind having a blade which is movable between an extended or operative position and a retracted or inorperative position. It is usual for the blade to be contained within a handle of the knife when retracted, and the invention will be hereinafter described with particular reference to that form of knife.
- Retractable blade knives of the foregoing kind are generally constructed so that a worn or damaged blade can be removed and replaced by a new blade.
- Example constructions of that kind are disclosed by U.S. patents 3,577,637, 3,593,417 and 4,242,795. It is not convenient to sharpen the blade in knives of the foregoing kind and as a result blade replacement may occur or be required at relatively short intervals of time.
- a retractable blade knife including, a hollow handle, a blade opening at a front end of said handle, a blade carrier mounted within said handle for movement between a rest position at which a blade connected to said carrier is contained within said handle and a forward position at which the said blade is projected through said opening beyond said handle front end, actuator means connected to said carrier and being operable to cause said movement thereof, a blade sharpener located within said handle adjacent said opening and being mounted for movement relative to said handle, biasing means urging said sharpener towards a stop position at which the sharpener prevents movement of a said blade forwardly through said opening, release means operable to move said sharpener away from said stop position and into a release position at which a said blade is able to be moved forwardly through said opening, and said sharpener is engageable with the cutting edge of a said blade so as to sharpen that edge as said blade is moved through said opening.
- a retractable blade knife including, a hollow handle, a blade opening at a front end of said handle, a blade carrier mounted within said handle, a blade removably connected to said carrier, said carrier being movable relative to said handle between a rest position at which said blade is contained within said handle and a forward position at which said blade is projected through said opening beyond said handle front end, actuator means operable to cause said carrier movement, a blade sharpener located within said handle adjacent said opening and being operable to engage the cutting edge of said blade so as to sharpen that edge during movement of said blade with said carrier, said sharpener including sharpening means which is engageable with said cutting edge and which is located forwardly of the front end of said blade when said carrier is in said rest position, and release means connected to said sharpener and being selectively operable to render said sharpener inoperable.
- a retractable blade knife including, a hollow handle, a blade opening at a front end of said handle, a blade carrier mounted within said handle for movement relative thereto, connecting means whereby a blade can be connected to and removed from said carrier, said carrier being movable between a rest position at which a blade connected to said carrier is contained within said handle and a forward position at which the said blade is projected through said opening beyond said handle front end, actuator means operable to cause said carrier movement, a blade sharpener located within said handle adjacent said opening and being operable to engage the cutting edge of the said blade so as to sharpen that edge during movement of said blade through said opening, and sharpener release means which is selectively operable to render said sharpener inoperable.
- a retractable blade knife including, a hollow handle, a blade opening at a front end of said handle, a blade carrier mounted within said handle for movement between a rest position at which a blade connected to said carrier is contained within said handle and a forward position at which the said blade is projected through said opening beyond said handle front end, actuator means operable to cause said carrier movement, a blade sharpener located within said handle adjacent said opening and being engageable with the cutting edge of a said blade so as to sharpen that edge as said blade is moved with said carrier, and stop means mounted on said handle for movement between a stop position at which it is operative to prevent movement of a said blade forwardly through said opening and a release position at which it is not so operative, and release means which is operable to move said stop means from said stop position to said release position.
- a retractable blade knife including, a hollow handle, a blade opening at a front end of said handle, a blade carrier mounted within said handle for movement between a rest position at which a blade connected to said carrier is contained within said handle and a forward position at which the said blade is projected through said opening beyond said handle front end, actuator means operable to cause said carrier movement, a blade sharpener located within said handle adjacent said opening and being operable to engage the cutting edge of the said blade so as to sharpen that edge during movement of said blade through said opening, and releasable locking means which is operable to prevent movement of said carrier out of said forward position.
- the blade sharpener is arranged so that when it engages the cutting edge of a blade it automatically sharpens that blade as a consequence of movement of the blade into or out of the knife handle.
- the sharpening operation is most effective during withdrawal of the blade into the handle, and means is provided to enable that sharpener to be held inoperative during at least part of the movement of the blade into its extended operative position.
- the knife includes an elongate handle 1 having a passage 2 ( Figures 5 and 6) extending lengthwise therein. That passage 2 is defined between an upper wall 3, a lower wall 4, and two side walls 5 and 6, and extends from a rear end portion 7 of the handle 1 to a front end wall 8.
- An opening 9 ( Figure 6) is provided through the front end wall 8 to permit movement of a blade 10 into and out of the handle passage 2.
- that opening 9 is in the form of a narrow slot extending between upper and lower sides of the handle 1 and which is dimensioned to allow passage of the knife blade 10 with little clearance. That is, it is preferred that the opening 9 is dimensioned so as to at least minimise lateral movement of the blade 10 relative to the handle 1, and preferably also provide a support which is engageable by the upper edge 11 of the blade 10 when the knife is in use.
- the rear end portion 7 of the handle 1 is removable in the construction shown to enable access to the interior of the handle 1. Removal of that end portion 7 may be employed to enable exchange of the knife blade 10 if it becomes worn or damaged.
- the handle 1 may include a spare blade storage compartment 12 ( Figure 5) which is accessible as a consequence of removing the end portion 7.
- the compartment 12 may be adapted to contain a single spare blade (not shown), or a plurality of such blades.
- the end portion 7 is slidably engaged with the main body 13 of the handle 1 so as to be relatively movable in a direction transverse to the longitudinal axis of the handle 1.
- Keying ribs 14 (Figures 1 and 3) provided on the end portion 7 slidably engage within complementary slots formed in the handle main body 13 so as to hold the end portion 7 against endwise removal from the main body 13.
- Snap engaging means comprising a detent 15 ( Figures 3 and 4) may be provided on the end portion 7 for cooperation with the main body 13 so as to resist inadvertent dislodgement of the end portion 7 from the main body 13.
- the detent 15 is at the end of a flexible arm 16 formed integral with the end portion 7.
- the blade 10 may be of any suitable form, but is generally of plate-like form having a substantially straight cutting edge 17. It is preferred that a front edge 18 and the upper edge 11 of the blade 10 are also substantially straight and that the front edge slopes upwardly and rearwardly from a tip 19 at its junction with the cutting edge 17. In such a case, it is also preferred that the front wall 8 of the knife handle 1 slopes downwardly and rearwardly as shown so as to expose a substantial part of the blade cutting edge 17 when the blade 10 is extended ( Figure 1). It is also preferred that the blade 10 is double ended so as to be reversible.
- a blade carrier 20 (Figure 16) is mounted within the knife handle passage 2 for sliding movement towards and away from the front wall 8.
- That carrier 20 can be of any suitable form such as to provide support for a blade 10, and any appropriate releasable connection can be provided between the blade 10 and the carrier 20 to ensure that the blade 10 moves with the carrier 20.
- that connection includes a plurality of laterally projecting pins 21 on a side surface 22 of the carrier 20, each of which neatly engages within a respective hole 23 formed through a portion 24 of the blade 10 which overlies the carrier surface 22. Confinement of the blade 10 within the handle 1 may be such as to prevent the carrier pins 21 disengaging from the blade holes 23.
- Exchange of a blade 10 may be effected by sliding the carrier 20 and connected blade 10 out of the handle 1 through the rear end thereof. Such removal is of course prevented while the rear end portion 7 of the handle 1 remains in place.
- the carrier 20 is movable between two extreme positions. One is a rest position as shown in Figure 8, and in that position the blade 10 is fully contained within the handle 1. The other is a forward position as shown in Figure 7, and in that position the blade 10 has been projected through the opening 9 so as to extend beyond the handle front wall 8. That is, the blade 10 is positioned so as to be operative.
- Movement of the carrier 20 may be effected through any suitable actuator means, but in the construction shown that actuator means comprises a lever 27 which is pivotally connected at an inner end 28 to the carrier 20 for relative movement between an operative position ( Figures 12 and 13) and a stored position ( Figure 14). Also, the lever 27 is preferably arranged to be accessible at the side wall 5 of the handle 1.
- the lever 27 is pivotally connected to the carrier 20 so that it can be swung about a pivot 29 ( Figure 12) having its axis extending between the upper and lower walls 3 and 4 of the handle 1.
- An elongate opening 30 is provided in the side wall 5 to accommodate the lever 27 when it is in the stored position.
- the length of the opening 30 is such as to accommodate the full length of the lever 27 without substantial clearance at either end.
- One end 31 of the opening 30 is formed by a surface 32 ( Figure 3) of the handle end portion 7.
- the pivoted inner end 28 of the lever 27 is adjacent the rear end portion 7 of the handle 1 when the lever 27 is in its stored position and the knife blade 10 is retracted (Figure 8).
- the outer or free end 33 of the lever 27 is located towards the front end of the handle 1 under those circumstances, and the lever 27 is substantially contained within the opening 30.
- a raised finger engageable portion 48 of the lever 27 is accessible to permit the lever 27 to be pulled outwards about the pivot 29 to adopt the operative position as shown in Figure 13.
- the lever 27 When it is desired to extend the blade 10, the lever 27 is pivoted laterally outwards from the handle 1 and is pushed forward so that the carrier 20 and connected blade 10 also move forward. The blade 10 is thereby projected through the front wall opening 9 of the handle 1 to adopt the extended position as shown in Figure 1. At that time the pivoted inner end 28 of the lever 27 is at the forwardmost end of the opening 30 in the handle side wall 5 and the lever 27 can be swung inwards to be again accommodated in that opening 30. The relative disposition of the lever ends 28 and 33, however, is now the reverse of that existing when the blade 10 is retracted.
- Positive locking means is provided to prevent the blade 10 being inadvertently pushed back into the handle 1 from the extended position when the blade 10 is subjected to endwise pressure in use.
- that locking means includes the lever 27 and a cooperative abutment surface formed by the end 31 of the handle opening 30. That is, when the lever 27 is accommodated within the opening 30 as shown in Figure 14, the outer end 33 of the lever 27 is arranged in opposed relationship to that abutment surface so as to positively resist rearward movement of the carrier 20. Pivotal movement of the lever 27 out of the opening 30 releases that locking arrangement by removing the lever end 33 from a position at which it can engage the abutment surface.
- Stop means is provided to prevent inadvertent movement of the blade 10 into the extended position. That may include a movable stop member located within the handle 1 which is engageable with the blade 10 or a cooperable part of the carrier 20. That is, when the carrier 20 is at the rest position, that stop member is arranged to be engaged by the blade 10 or the carrier 20 such as to prevent forward movement of the carrier 20 beyond a particular position.
- the stop means is formed by cooperable parts of a blade sharpener 34 and the carrier 20, but other arrangements are possible.
- the sharpener 34 is located within the handle 1 adjacent the front wall 8, and its function and construction will be further described below.
- the sharpener 34 includes a body member 35 and the stop means part of the sharpener 34 is formed by a lateral projection 36 provided on a rear end portion of an arm 37 which is connected to and extends rearwardly from the body member 35.
- the cooperable part of the carrier 20 is formed by the front end portion 25 of a laterally projecting lip 26 formed along the upper side of the carrier 20.
- the carrier stop part 25 is located rearwardly of the sharpener stop part 36. Forward movement of the carrier 20 results in the stop part 25 engaging the stop part 36, and further forward movement is thereby prevented. At that time, the blade 10 has not been projected through the opening 9.
- Release means is provided whereby the stop means can be selectively rendered inoperable.
- that release means is connected to the sharpener 34 so as to be operable to move the stop part 36 out of the path of the carrier stop part 25 and thereby permit extension of the blade 10.
- That release means includes a button 38 which is accessible at the upper side of the handle 1 and which is spring biased into an upper stop operative position as shown in Figure 9. Depression of the button 38 against the influence of the biasing spring 39 is effective to move the stop part 36 into its inoperative position as shown by Figure 10.
- the button biasing spring 39 is preferably formed by a resilient arm as shown in Figure 6 which extends lengthwise of the handle 1, and has one end 40 fixed to the handle 1 and its opposite end 41 attached to the sharpener 34.
- the spring end 40 is preferably secured to the handle adjacent the rear end thereof as shown.
- the arrangement is such that the spring 39 normally urges the sharpener 34 and connected button 38 in an upward direction and any appropriate means may be provided to limit such upward movement.
- the sharpener 34 and/or button 38 may cooperate with appropriate guide means provided on or within the handle 1 so as to be confined to a particular path of movement.
- Sharpening means 42 is provided on the sharpener 34 and is arranged so as to be operative to automatically sharpen the cutting edge 17 of the blade 10.
- the sharpening means 42 is not engageable with the blade cutting edge 17 when the button 38 is depressed, but is so engageable when the button 38 is allowed to move upwards under the influence of its biasing spring 39. It is an important feature of the construction shown that the tip 19 of the blade 10 is located rearwards of the sharpening means 42 when the blade 10 is fully retracted.
- the release button 38 it is necessary to depress the release button 38 to permit extension of the blade 10 and as a consequence the blade 10 does not contact the sharpening means 42, at least during the initial part of that extension movement. If the button 38 is released during the course of that movement, there may be sharpening engagement, but that is not essential nor is it preferred. When the blade 10 is fully extended, the button 38 is released so that the sharpening means 42 is moved into engagement with part of the blade cutting edge 17 which is located within the handle 1 and is therefore not normally operative.
- the stop part 36 is provided with a ramp surface 45 and the stop part 25 is provided with a ramp surface 46.
- the ramp surfaces 45 and 46 may be flat or curved as required.
- the ramp surfaces 45 and 46 are arranged in opposed relationship as shown by Figure 11. Rearward movement of the carrier 20 results in those two surfaces 45 and 46 engaging with the consequence that the sharpener 34 is ramped upwards against the action of the spring 39, and the carrier 20 can continue to move rearward.
- the stop means is thereby automatically rendered inoperative during rearward movement of the carrier. Other arrangements could be adopted to achieve the same result.
- the sharpening means 42 can be of any suitable form. In the construction shown, it comprises a device having a pair of cutting plates 43 of tungsten carbide or other suitable material and which are relatively arranged to define a V-shaped sharpening recess 44 between them. Preferably, the plates 43 overlap to define that recess 44 and are in face to face relationship. It is further preferred that the plates 43 slope upwardly and rearwardly to facilitate a relatively smooth sharpening action during retraction of the blade 10.
- a third blade or a rubbing member may be located opposite to the rearmost plate 43 of the pair referred to. That third blade or rubbing member can be arranged to prevent or minimise the aforementioned deflection and thereby ensure that effective sharpening of the blade 10 is carried up to the tip 19 of the blade 10.
- a channel-shaped metal insert 47 ( Figures 6 and 15) is preferably provided at the top of the handle opening 9. That insert 47 receives an upper edge portion of the knife blade 10 and provides a rigid and wear resistant support against which the upper edge 11 of the blade 10 can bear during use and movement into and out of the handle 1.
- the present invention provides an effective knife of the retractable blade type, particularly in the ability to prevent inadvertent extension of the blade and to also provide for self-sharpening of the blade.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Life Sciences & Earth Sciences (AREA)
- Forests & Forestry (AREA)
- Knives (AREA)
Abstract
Description
- This invention relates to knives of the kind having a blade which is movable between an extended or operative position and a retracted or inorperative position. It is usual for the blade to be contained within a handle of the knife when retracted, and the invention will be hereinafter described with particular reference to that form of knife.
- Retractable blade knives of the foregoing kind are generally constructed so that a worn or damaged blade can be removed and replaced by a new blade. Example constructions of that kind are disclosed by U.S. patents 3,577,637, 3,593,417 and 4,242,795. It is not convenient to sharpen the blade in knives of the foregoing kind and as a result blade replacement may occur or be required at relatively short intervals of time.
- It has been proposed in the past to provide a retractable blade knife with a self-sharpening facility, and U.S. patent 1,890,506 (Frank) discloses that particular construction. The Frank knife is not known to have been manufactured in commercial quantities, and is distinguished from the other retractable blade knives referred to above in that the blade is not readily replaced. It has the further disadvantage in that retraction of the blade extends rather than reduces the overall size of the knife. The Frank knife is also not satisfactory because the self-sharpening facility does not sharpen the entire length of the blade cutting edge, and in particular does not and cannot sharpen the very tip of the blade which is often the most used portion of the blade.
- Another common problem with knives of the foregoing kind is that the blade is not firmly restrained in the extended position so that pressure on the blade during use can cause unintentional retraction of the blade.
- It is an object of the present invention to provide a knife of the foregoing kind which has an effective self-sharpening facility. It is another object to provide such a knife having means to prevent inadvertent extension of the blade. It is a further object to provide such a knife with means whereby the blade is positively retained in the extended position.
- According to one aspect of the present invention, there is provided a retractable blade knife including, a hollow handle, a blade opening at a front end of said handle, a blade carrier mounted within said handle for movement between a rest position at which a blade connected to said carrier is contained within said handle and a forward position at which the said blade is projected through said opening beyond said handle front end, actuator means connected to said carrier and being operable to cause said movement thereof, a blade sharpener located within said handle adjacent said opening and being mounted for movement relative to said handle, biasing means urging said sharpener towards a stop position at which the sharpener prevents movement of a said blade forwardly through said opening, release means operable to move said sharpener away from said stop position and into a release position at which a said blade is able to be moved forwardly through said opening, and said sharpener is engageable with the cutting edge of a said blade so as to sharpen that edge as said blade is moved through said opening.
- According to another aspect of the invention, there is provided a retractable blade knife including, a hollow handle, a blade opening at a front end of said handle, a blade carrier mounted within said handle, a blade removably connected to said carrier, said carrier being movable relative to said handle between a rest position at which said blade is contained within said handle and a forward position at which said blade is projected through said opening beyond said handle front end, actuator means operable to cause said carrier movement, a blade sharpener located within said handle adjacent said opening and being operable to engage the cutting edge of said blade so as to sharpen that edge during movement of said blade with said carrier, said sharpener including sharpening means which is engageable with said cutting edge and which is located forwardly of the front end of said blade when said carrier is in said rest position, and release means connected to said sharpener and being selectively operable to render said sharpener inoperable.
- According to still another aspect of the invention, there is provided a retractable blade knife including, a hollow handle, a blade opening at a front end of said handle, a blade carrier mounted within said handle for movement relative thereto, connecting means whereby a blade can be connected to and removed from said carrier, said carrier being movable between a rest position at which a blade connected to said carrier is contained within said handle and a forward position at which the said blade is projected through said opening beyond said handle front end, actuator means operable to cause said carrier movement, a blade sharpener located within said handle adjacent said opening and being operable to engage the cutting edge of the said blade so as to sharpen that edge during movement of said blade through said opening, and sharpener release means which is selectively operable to render said sharpener inoperable.
- According to yet another aspect of the invention, there is provided a retractable blade knife including, a hollow handle, a blade opening at a front end of said handle, a blade carrier mounted within said handle for movement between a rest position at which a blade connected to said carrier is contained within said handle and a forward position at which the said blade is projected through said opening beyond said handle front end, actuator means operable to cause said carrier movement, a blade sharpener located within said handle adjacent said opening and being engageable with the cutting edge of a said blade so as to sharpen that edge as said blade is moved with said carrier, and stop means mounted on said handle for movement between a stop position at which it is operative to prevent movement of a said blade forwardly through said opening and a release position at which it is not so operative, and release means which is operable to move said stop means from said stop position to said release position.
- According to a further aspect of the invention, there is provided a retractable blade knife including, a hollow handle, a blade opening at a front end of said handle, a blade carrier mounted within said handle for movement between a rest position at which a blade connected to said carrier is contained within said handle and a forward position at which the said blade is projected through said opening beyond said handle front end, actuator means operable to cause said carrier movement, a blade sharpener located within said handle adjacent said opening and being operable to engage the cutting edge of the said blade so as to sharpen that edge during movement of said blade through said opening, and releasable locking means which is operable to prevent movement of said carrier out of said forward position.
- The blade sharpener is arranged so that when it engages the cutting edge of a blade it automatically sharpens that blade as a consequence of movement of the blade into or out of the knife handle. In a preferred embodiment hereinafter described, the sharpening operation is most effective during withdrawal of the blade into the handle, and means is provided to enable that sharpener to be held inoperative during at least part of the movement of the blade into its extended operative position.
- An embodiment of the invention is described in detail in the following passages of the specificaton which refer to the accompanying drawings. The drawings, however, are merely illustrative of how the invention might be put into effect, so that the specific form and arrangement of the various features as shown is not to be understood as limiting on the invention.
- In the drawings:
- Figure 1 is a side elevational view of one form of retractable blade knife incorporating an embodiment of the invention,
- Figure 2 is a top plan view of the knife shown in Figure 1,
- Figure 3 is a partially sectioned and exploded view of the rear end portion of the knife shown in Figure 1,
- Figure 4 is an end view of the removable end portion shown in Figure 3,
- Figure 5 is a cross-sectional view taken along line V-V of Figure 1,
- Figure 6 is a longitudinal sectional view of the knife shown in Figures 1 and 2, but with parts omitted for convenience of illustration,
- Figure 7 is a sectional view taken along line VII-VII of Figure 5,
- Figure 8 is a view similar to Figure 7 but showing the blade fully retracted,
- Figure 9 is a view similar to Figure 8 but with parts omitted for convenience of illustration,
- Figure 10 is a view similar to Figure 9 but showing the stop means rendered inoperative,
- Figure 11 is a view similar to Figure 10 and showing the blade carrier in a forward position,
- Figure 12 is a part sectional view showing the manner of actuation of the blade carrier of the knife of Figure 1,
- Figure 13 is a view similar to Figure 12 but showing the blade carrier moved to its forwardmost position,
- Figure 14 is a view similar to Figure 13 and showing the blade actuator in its stored position,
- Figure 15 is a cross-sectional view taken along line XV-XV of Figure 6.
- Figure 16 is a view taken along line XVI-XVI of Figure 14.
- According to the example form shown in the drawings, the knife includes an elongate handle 1 having a passage 2 (Figures 5 and 6) extending lengthwise therein. That
passage 2 is defined between anupper wall 3, a lower wall 4, and twoside walls 5 and 6, and extends from a rear end portion 7 of the handle 1 to a front end wall 8. An opening 9 (Figure 6) is provided through the front end wall 8 to permit movement of ablade 10 into and out of thehandle passage 2. Preferably, that opening 9 is in the form of a narrow slot extending between upper and lower sides of the handle 1 and which is dimensioned to allow passage of theknife blade 10 with little clearance. That is, it is preferred that the opening 9 is dimensioned so as to at least minimise lateral movement of theblade 10 relative to the handle 1, and preferably also provide a support which is engageable by the upper edge 11 of theblade 10 when the knife is in use. - The rear end portion 7 of the handle 1 is removable in the construction shown to enable access to the interior of the handle 1. Removal of that end portion 7 may be employed to enable exchange of the
knife blade 10 if it becomes worn or damaged. Also, the handle 1 may include a spare blade storage compartment 12 (Figure 5) which is accessible as a consequence of removing the end portion 7. Thecompartment 12 may be adapted to contain a single spare blade (not shown), or a plurality of such blades. - In the arrangement shown, the end portion 7 is slidably engaged with the
main body 13 of the handle 1 so as to be relatively movable in a direction transverse to the longitudinal axis of the handle 1. Keying ribs 14 (Figures 1 and 3) provided on the end portion 7 slidably engage within complementary slots formed in the handlemain body 13 so as to hold the end portion 7 against endwise removal from themain body 13. Snap engaging means comprising a detent 15 (Figures 3 and 4) may be provided on the end portion 7 for cooperation with themain body 13 so as to resist inadvertent dislodgement of the end portion 7 from themain body 13. As best seen in Figure 4, thedetent 15 is at the end of aflexible arm 16 formed integral with the end portion 7. - The
blade 10 may be of any suitable form, but is generally of plate-like form having a substantially straight cutting edge 17. It is preferred that afront edge 18 and the upper edge 11 of theblade 10 are also substantially straight and that the front edge slopes upwardly and rearwardly from atip 19 at its junction with the cutting edge 17. In such a case, it is also preferred that the front wall 8 of the knife handle 1 slopes downwardly and rearwardly as shown so as to expose a substantial part of the blade cutting edge 17 when theblade 10 is extended (Figure 1). It is also preferred that theblade 10 is double ended so as to be reversible. - A blade carrier 20 (Figure 16) is mounted within the
knife handle passage 2 for sliding movement towards and away from the front wall 8. Thatcarrier 20 can be of any suitable form such as to provide support for ablade 10, and any appropriate releasable connection can be provided between theblade 10 and thecarrier 20 to ensure that theblade 10 moves with thecarrier 20. In the construction shown, that connection includes a plurality of laterally projecting pins 21 on aside surface 22 of thecarrier 20, each of which neatly engages within arespective hole 23 formed through aportion 24 of theblade 10 which overlies thecarrier surface 22. Confinement of theblade 10 within the handle 1 may be such as to prevent the carrier pins 21 disengaging from theblade holes 23. - Exchange of a
blade 10 may be effected by sliding thecarrier 20 and connectedblade 10 out of the handle 1 through the rear end thereof. Such removal is of course prevented while the rear end portion 7 of the handle 1 remains in place. - The
carrier 20 is movable between two extreme positions. One is a rest position as shown in Figure 8, and in that position theblade 10 is fully contained within the handle 1. The other is a forward position as shown in Figure 7, and in that position theblade 10 has been projected through the opening 9 so as to extend beyond the handle front wall 8. That is, theblade 10 is positioned so as to be operative. - Movement of the
carrier 20 may be effected through any suitable actuator means, but in the construction shown that actuator means comprises alever 27 which is pivotally connected at aninner end 28 to thecarrier 20 for relative movement between an operative position (Figures 12 and 13) and a stored position (Figure 14). Also, thelever 27 is preferably arranged to be accessible at the side wall 5 of the handle 1. - According to the arrangement shown, the
lever 27 is pivotally connected to thecarrier 20 so that it can be swung about a pivot 29 (Figure 12) having its axis extending between the upper andlower walls 3 and 4 of the handle 1. Anelongate opening 30 is provided in the side wall 5 to accommodate thelever 27 when it is in the stored position. The length of theopening 30 is such as to accommodate the full length of thelever 27 without substantial clearance at either end. Oneend 31 of theopening 30 is formed by a surface 32 (Figure 3) of the handle end portion 7. - The pivoted
inner end 28 of thelever 27 is adjacent the rear end portion 7 of the handle 1 when thelever 27 is in its stored position and theknife blade 10 is retracted (Figure 8). The outer orfree end 33 of thelever 27 is located towards the front end of the handle 1 under those circumstances, and thelever 27 is substantially contained within theopening 30. A raisedfinger engageable portion 48 of thelever 27 is accessible to permit thelever 27 to be pulled outwards about thepivot 29 to adopt the operative position as shown in Figure 13. - When it is desired to extend the
blade 10, thelever 27 is pivoted laterally outwards from the handle 1 and is pushed forward so that thecarrier 20 and connectedblade 10 also move forward. Theblade 10 is thereby projected through the front wall opening 9 of the handle 1 to adopt the extended position as shown in Figure 1. At that time the pivotedinner end 28 of thelever 27 is at the forwardmost end of theopening 30 in the handle side wall 5 and thelever 27 can be swung inwards to be again accommodated in thatopening 30. The relative disposition of the lever ends 28 and 33, however, is now the reverse of that existing when theblade 10 is retracted. - Positive locking means is provided to prevent the
blade 10 being inadvertently pushed back into the handle 1 from the extended position when theblade 10 is subjected to endwise pressure in use. In the construction shown, that locking means includes thelever 27 and a cooperative abutment surface formed by theend 31 of thehandle opening 30. That is, when thelever 27 is accommodated within theopening 30 as shown in Figure 14, theouter end 33 of thelever 27 is arranged in opposed relationship to that abutment surface so as to positively resist rearward movement of thecarrier 20. Pivotal movement of thelever 27 out of theopening 30 releases that locking arrangement by removing the lever end 33 from a position at which it can engage the abutment surface. - Stop means is provided to prevent inadvertent movement of the
blade 10 into the extended position. That may include a movable stop member located within the handle 1 which is engageable with theblade 10 or a cooperable part of thecarrier 20. That is, when thecarrier 20 is at the rest position, that stop member is arranged to be engaged by theblade 10 or thecarrier 20 such as to prevent forward movement of thecarrier 20 beyond a particular position. - In the preferred construction shown, the stop means is formed by cooperable parts of a
blade sharpener 34 and thecarrier 20, but other arrangements are possible. Thesharpener 34 is located within the handle 1 adjacent the front wall 8, and its function and construction will be further described below. Thesharpener 34 includes abody member 35 and the stop means part of thesharpener 34 is formed by alateral projection 36 provided on a rear end portion of an arm 37 which is connected to and extends rearwardly from thebody member 35. The cooperable part of thecarrier 20 is formed by thefront end portion 25 of a laterally projectinglip 26 formed along the upper side of thecarrier 20. - When the
carrier 20 is at the rest position as shown in Figure 8, the carrier stoppart 25 is located rearwardly of the sharpener stoppart 36. Forward movement of thecarrier 20 results in thestop part 25 engaging thestop part 36, and further forward movement is thereby prevented. At that time, theblade 10 has not been projected through the opening 9. - Release means is provided whereby the stop means can be selectively rendered inoperable. In the construction shown, that release means is connected to the
sharpener 34 so as to be operable to move thestop part 36 out of the path of the carrier stoppart 25 and thereby permit extension of theblade 10. That release means includes abutton 38 which is accessible at the upper side of the handle 1 and which is spring biased into an upper stop operative position as shown in Figure 9. Depression of thebutton 38 against the influence of the biasingspring 39 is effective to move thestop part 36 into its inoperative position as shown by Figure 10. - The
button biasing spring 39 is preferably formed by a resilient arm as shown in Figure 6 which extends lengthwise of the handle 1, and has oneend 40 fixed to the handle 1 and itsopposite end 41 attached to thesharpener 34. Thespring end 40 is preferably secured to the handle adjacent the rear end thereof as shown. The arrangement is such that thespring 39 normally urges thesharpener 34 and connectedbutton 38 in an upward direction and any appropriate means may be provided to limit such upward movement. Furthermore, thesharpener 34 and/orbutton 38 may cooperate with appropriate guide means provided on or within the handle 1 so as to be confined to a particular path of movement. - Sharpening means 42 is provided on the
sharpener 34 and is arranged so as to be operative to automatically sharpen the cutting edge 17 of theblade 10. In the arrangement shown, the sharpeningmeans 42 is not engageable with the blade cutting edge 17 when thebutton 38 is depressed, but is so engageable when thebutton 38 is allowed to move upwards under the influence of its biasingspring 39. It is an important feature of the construction shown that thetip 19 of theblade 10 is located rearwards of the sharpeningmeans 42 when theblade 10 is fully retracted. - With the foregoing arrangement, it is necessary to depress the
release button 38 to permit extension of theblade 10 and as a consequence theblade 10 does not contact the sharpeningmeans 42, at least during the initial part of that extension movement. If thebutton 38 is released during the course of that movement, there may be sharpening engagement, but that is not essential nor is it preferred. When theblade 10 is fully extended, thebutton 38 is released so that the sharpeningmeans 42 is moved into engagement with part of the blade cutting edge 17 which is located within the handle 1 and is therefore not normally operative. - Retraction of the
blade 10 does not require depression of therelease button 38. Consequently, the sharpening means 42 remains in engagement with and sharpens the cutting edge 17 during movement of theblade 10 back into the handle 1. Furthermore, that sharpening is effected up to thevery tip 19 of theblade 10 because theblade 10 is moved rearwardly beyond the sharpeningmeans 42 when adopting the fully retracted position. Such full retraction has the affect of automatically conditioning the stop means to be operative, because thespring 39 urges thesharpener 34 into its uppermost position when theblade 10 moves clear of the sharpeningmeans 42. - As will be apparent from Figures 9 to 11, the
stop part 36 is provided with aramp surface 45 and thestop part 25 is provided with aramp surface 46. The ramp surfaces 45 and 46 may be flat or curved as required. When thestop part 25 is located forwardly of thestop part 36, the ramp surfaces 45 and 46 are arranged in opposed relationship as shown by Figure 11. Rearward movement of thecarrier 20 results in those twosurfaces sharpener 34 is ramped upwards against the action of thespring 39, and thecarrier 20 can continue to move rearward. The stop means is thereby automatically rendered inoperative during rearward movement of the carrier. Other arrangements could be adopted to achieve the same result. - The sharpening means 42 can be of any suitable form. In the construction shown, it comprises a device having a pair of cutting plates 43 of tungsten carbide or other suitable material and which are relatively arranged to define a V-shaped sharpening
recess 44 between them. Preferably, the plates 43 overlap to define thatrecess 44 and are in face to face relationship. It is further preferred that the plates 43 slope upwardly and rearwardly to facilitate a relatively smooth sharpening action during retraction of theblade 10. - Since the two plates 43 are out of lateral alignment, only one will be engaged by the
blade 10 during the final part of the retracting movement of theblade 10 over the sharpeningdevice 42. That may cause lateral deflection of theblade 10 and consequently an absence of sharpening at one side of the blade tip. If such deflection does occur, a third blade or a rubbing member may be located opposite to the rearmost plate 43 of the pair referred to. That third blade or rubbing member can be arranged to prevent or minimise the aforementioned deflection and thereby ensure that effective sharpening of theblade 10 is carried up to thetip 19 of theblade 10. - A channel-shaped metal insert 47 (Figures 6 and 15) is preferably provided at the top of the handle opening 9. That insert 47 receives an upper edge portion of the
knife blade 10 and provides a rigid and wear resistant support against which the upper edge 11 of theblade 10 can bear during use and movement into and out of the handle 1. - It will be apparent from the foregoing description that the present invention provides an effective knife of the retractable blade type, particularly in the ability to prevent inadvertent extension of the blade and to also provide for self-sharpening of the blade.
- Various alterations, modifications and/or additions may be introduced into the constructions and arrangements of parts previously described without departing from the spirit or ambit of the invention as defined by the appended claims.
Claims (23)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
AT87309976T ATE56906T1 (en) | 1986-11-12 | 1987-11-11 | KNIFE WITH RETRACTABLE BLADE. |
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
AU8907/86 | 1986-11-12 | ||
AUPH890786 | 1986-11-12 | ||
AU80988/87A AU586129B2 (en) | 1986-11-12 | 1987-11-10 | Retractable blade knife |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0271223A1 true EP0271223A1 (en) | 1988-06-15 |
EP0271223B1 EP0271223B1 (en) | 1990-09-26 |
Family
ID=25639645
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP87309976A Expired - Lifetime EP0271223B1 (en) | 1986-11-12 | 1987-11-11 | Retractable blade knife |
Country Status (1)
Country | Link |
---|---|
EP (1) | EP0271223B1 (en) |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0415604A1 (en) * | 1989-08-28 | 1991-03-06 | McPherson's Limited | Blade sharpener |
FR2715340A1 (en) * | 1994-01-26 | 1995-07-28 | Seb Sa | Sharpening sheath adapted to receive a knife and combination of such a sheath and a knife. |
WO1996011086A1 (en) * | 1994-10-05 | 1996-04-18 | Mcpherson's Limited | A blade scabbard |
AU685322B2 (en) * | 1994-10-05 | 1998-01-15 | Mcpherson's Limited | A blade scabbard |
US6718639B1 (en) | 2003-02-19 | 2004-04-13 | Byron John Kazanjian | Self-sharpening utility knife |
CN101564844B (en) * | 2009-03-27 | 2012-05-23 | 杭州巨星科技股份有限公司 | Manual knife for prohibiting knife handle from being opened accidentally |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2337158A (en) * | 1943-05-07 | 1943-12-21 | Earl L Frank | Knife with built-in sharpener |
US2700819A (en) * | 1952-12-15 | 1955-02-01 | Donald E Mason | Combined knife and sharpener |
US2744320A (en) * | 1953-05-19 | 1956-05-08 | Vincent J Palermo | Knife |
US3676961A (en) * | 1969-05-07 | 1972-07-18 | Wiltshire Cutlery Co Pty | Knife scabbard or holder |
US3846909A (en) * | 1973-10-29 | 1974-11-12 | R Clarke | Combination of a knife and sharpener |
GB2161737A (en) * | 1984-07-16 | 1986-01-22 | Nippon Tenshashi Kk | Magazine type knife |
Family Cites Families (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3577637A (en) * | 1968-09-24 | 1971-05-04 | Philip Morris Inc | Retractable blade knife |
US3593417A (en) * | 1969-08-13 | 1971-07-20 | Stanley Works | Hand tool having a holder for spare blades and the like |
-
1987
- 1987-11-11 EP EP87309976A patent/EP0271223B1/en not_active Expired - Lifetime
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2337158A (en) * | 1943-05-07 | 1943-12-21 | Earl L Frank | Knife with built-in sharpener |
US2700819A (en) * | 1952-12-15 | 1955-02-01 | Donald E Mason | Combined knife and sharpener |
US2744320A (en) * | 1953-05-19 | 1956-05-08 | Vincent J Palermo | Knife |
US3676961A (en) * | 1969-05-07 | 1972-07-18 | Wiltshire Cutlery Co Pty | Knife scabbard or holder |
US3846909A (en) * | 1973-10-29 | 1974-11-12 | R Clarke | Combination of a knife and sharpener |
GB2161737A (en) * | 1984-07-16 | 1986-01-22 | Nippon Tenshashi Kk | Magazine type knife |
Cited By (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0415604A1 (en) * | 1989-08-28 | 1991-03-06 | McPherson's Limited | Blade sharpener |
AU620001B2 (en) * | 1989-08-28 | 1992-02-06 | Mcpherson's Limited | Blade sharpener |
FR2715340A1 (en) * | 1994-01-26 | 1995-07-28 | Seb Sa | Sharpening sheath adapted to receive a knife and combination of such a sheath and a knife. |
EP0665086A1 (en) * | 1994-01-26 | 1995-08-02 | Seb S.A. | Sharpening sheath adapted for holding a knife and combination of such a sheath with a knife |
WO1996011086A1 (en) * | 1994-10-05 | 1996-04-18 | Mcpherson's Limited | A blade scabbard |
AU685322B2 (en) * | 1994-10-05 | 1998-01-15 | Mcpherson's Limited | A blade scabbard |
US5784786A (en) * | 1994-10-05 | 1998-07-28 | Mcpherson's Limited | Blade scabbard and sharpener |
US6718639B1 (en) | 2003-02-19 | 2004-04-13 | Byron John Kazanjian | Self-sharpening utility knife |
CN101564844B (en) * | 2009-03-27 | 2012-05-23 | 杭州巨星科技股份有限公司 | Manual knife for prohibiting knife handle from being opened accidentally |
Also Published As
Publication number | Publication date |
---|---|
EP0271223B1 (en) | 1990-09-26 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US4862590A (en) | Retractable blade knife | |
US7930829B2 (en) | Compact utility knife | |
US3781988A (en) | Safety paper carton opening blade holder | |
US4261104A (en) | Holder for detachable blades | |
EP0415604B1 (en) | Blade sharpener | |
CA1038628A (en) | Knife sharpener | |
US7520059B2 (en) | Compact utility knife | |
US5996231A (en) | Scraping tool with replaceable blade and controlled quick-release clamp | |
US5784786A (en) | Blade scabbard and sharpener | |
GB2349841A (en) | Cutting tool | |
US6117002A (en) | Blade sharpener | |
US2601723A (en) | Scraper employing razor blade | |
US4091691A (en) | Knife sharpener | |
EP0271223B1 (en) | Retractable blade knife | |
CA1303840C (en) | Retractable blade knife | |
CA1046774A (en) | Knife sharpener | |
EP0476568B1 (en) | Blade sharpener | |
CA1245454A (en) | Knife sharpener | |
AU766688B2 (en) | Blade sharpener | |
US4858319A (en) | Apparatus for ensuring that a knife is opened in a desired orientation | |
AU685322B2 (en) | A blade scabbard |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): AT BE CH DE FR GB IT LI NL SE |
|
17P | Request for examination filed |
Effective date: 19881026 |
|
17Q | First examination report despatched |
Effective date: 19890810 |
|
ITF | It: translation for a ep patent filed | ||
GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
AK | Designated contracting states |
Kind code of ref document: B1 Designated state(s): AT BE CH DE FR GB IT LI NL SE |
|
REF | Corresponds to: |
Ref document number: 56906 Country of ref document: AT Date of ref document: 19901015 Kind code of ref document: T |
|
REF | Corresponds to: |
Ref document number: 3765230 Country of ref document: DE Date of ref document: 19901031 |
|
ET | Fr: translation filed | ||
PLBE | No opposition filed within time limit |
Free format text: ORIGINAL CODE: 0009261 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT |
|
26N | No opposition filed | ||
ITTA | It: last paid annual fee | ||
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: GB Payment date: 19941006 Year of fee payment: 8 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: DE Payment date: 19941015 Year of fee payment: 8 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: FR Payment date: 19941018 Year of fee payment: 8 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: AT Payment date: 19941020 Year of fee payment: 8 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: CH Payment date: 19941026 Year of fee payment: 8 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: SE Payment date: 19941027 Year of fee payment: 8 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: BE Payment date: 19941128 Year of fee payment: 8 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: NL Payment date: 19941130 Year of fee payment: 8 |
|
EAL | Se: european patent in force in sweden |
Ref document number: 87309976.6 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: GB Effective date: 19951111 Ref country code: AT Effective date: 19951111 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: SE Effective date: 19951112 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: LI Effective date: 19951130 Ref country code: CH Effective date: 19951130 Ref country code: BE Effective date: 19951130 |
|
BERE | Be: lapsed |
Owner name: MCPHERSON'S LTD Effective date: 19951130 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: NL Effective date: 19960601 |
|
GBPC | Gb: european patent ceased through non-payment of renewal fee |
Effective date: 19951111 |
|
REG | Reference to a national code |
Ref country code: CH Ref legal event code: PL |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: FR Effective date: 19960731 |
|
NLV4 | Nl: lapsed or anulled due to non-payment of the annual fee |
Effective date: 19960601 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: DE Effective date: 19960801 |
|
EUG | Se: european patent has lapsed |
Ref document number: 87309976.6 |
|
REG | Reference to a national code |
Ref country code: FR Ref legal event code: ST |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: IT Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES;WARNING: LAPSES OF ITALIAN PATENTS WITH EFFECTIVE DATE BEFORE 2007 MAY HAVE OCCURRED AT ANY TIME BEFORE 2007. THE CORRECT EFFECTIVE DATE MAY BE DIFFERENT FROM THE ONE RECORDED. Effective date: 20051111 |