Abstract
A tool assembly is arranged for simultaneous treatment of both sides of the edge of a knife. The tool assembly comprises a tool in the form of a stave having faces extending longitudinally between first and second ends of the stave. A holder is provided in which the stave is journaled pivotally within a restricted pivot angle range (α) defined by a pivot limit function accomplished through interaction between the holder and the stave. A pivot journal means, for example, in the form of a pivot pin and a pinhole, is arranged for journaling the stave pivotally about a center axis of the stave.
Claims
1. An apparatus comprising at least two tools for treatment of an edge of a knife, wherein the at least two tools overlap each other at intersecting directions in order to form between the at least two tools a V-shaped groove into which a knife can be inserted and moved manually back and forth while in contact with the at least two tools for simultaneous treatment of both sides the edge of the knife, wherein the at least two tools are shaped as staves, wherein each stave comprises a body of rectangular cross-sectional profile comprising four faces extending in a longitudinal direction from a first end to a second end of the stave, wherein faces of the stave that are adjacent to each other are joined at corners running in the longitudinal direction of the stave, the stave having a longitudinal center axis; wherein each stave is arranged to extend cantilevered in crosswise relation to the other stave from a respective movable holder member extending from a respective slot formed in a top surface of a base holder member in which the respective movable holder member can move back and forth in side-by-side relation relative to the movable holder member of the other stave against a force of a spring which urges the respective movable holder member and stave towards an initial position; pivot means associated with each stave and respective movable holder member, said means comprising a pivot pin and a pinhole arranged, one in the stave and the other of said pivot pin or pinhole in the movable holder member, respectively, to permit rotation of the stave in the respective movable holder member about the center axis of the stave; wherein rotation of each stave about its center axis is limited between positions at which any corner of the stave hits a wall of said slot of said base holder member from which the stave and its respective movable holder member extends.
2. The apparatus of claim 1, wherein at least one of the staves comprises an equilateral cross-sectional geometry.
3. The apparatus of claim 1, wherein at least two faces of at least one of the staves carry an edge treatment surface respectively.
4. The apparatus of claim 1, wherein at least one of the staves comprises edge treatment surfaces located on opposite faces of the stave.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) Embodiments of the invention will be explained below with reference made to the accompanying schematic drawings, wherein
(2) FIG. 1 shows a first embodiment of a tool for treatment of the edge of a knife three-dimensional view,
(3) FIG. 2 shows an alternative embodiment of the tool in three-dimensional view,
(4) FIG. 3 shows the pivotal journaling of a tool in one end of a tool holder of a first embodiment,
(5) FIG. 4 shows a pivot limit function effective to limit the pivotal movement of the tool in its mounted position in the tool holder of FIG. 3,
(6) FIG. 5 shows the pivotal journaling of a tool in an opposite end of the tool holder of FIGS. 3 and 4,
(7) FIG. 6-8 are partially sectioned views showing alternative embodiments of the tool for treatment of the edge of a knife,
(8) FIGS. 9-10 show the pivotal journaling of a tool in a tool holder of a second embodiment,
(9) FIG. 11 shows an alternative one-end journaling of the tool on a singular pivot pin,
(10) FIG. 12 is a top view of the tool assembly shown in FIG. 13, and
(11) FIG. 13 shows the tool assembly of FIG. 12 in a sectional view taken along line XII-XII in FIG. 12.
DETAILED DESCRIPTION OF THE INVENTION
(12) A tool 10 for treatment of the edge of a knife is shown in three-dimensional view in FIG. 1. The tool 10 has an elongate body 11 reaching from a first end 12 to a second end 13. The body 11 is defined by its sides or faces 14 which can be three or more in numbers.
(13) In the embodiments of FIGS. 1 and 2, the body 11 has a four-faced rectangular sectional profile wherein adjacent faces 14 are joined at corners h running in the length of the body 11.
(14) At least one, preferably two or more of the faces 14 has a surface which is effective for treatment of a knife edge. The tool 10 has a length which is larger than the width thereof and may in this respect be seen as a cornered stave. Thus, the stave 10 has a pivot axis S that runs through the body 11 in the length direction of the stave 10, internally of the faces 14. “Internally” of the faces means that a normal through the pivot axis from the most adjacent face of the stave forms the radius of a circle that is fully located within the sectional profile of the stave. Since the pivot axis S is located internally of the faces 14, any one face is optionally available for treatment of the edge of a knife. The pivot axis S may also constitute the center axis of the stave 10. Accordingly, although not mandatory, all corners of the stave may be located on a circle at the same radial distance from the pivot axis S.
(15) A pivot journal means in the form of a pinhole 15 is arranged in at least one end 12 or 13 of the stave 10. From its mouth in the end of the stave, the pinhole extends for a length into the body 11 in concentric relation to the pivot axis S. A corresponding pinhole may be arranged in the opposite end of the stave 10.
(16) Pinholes 15 can be of various lengths. For example, the pinhole 15 may be a blind-hole or extended all through the body 11 so as to mouth in both ends 12 and 13. FIG. 2 shows an alternative embodiment of the tool for treatment of the edge of a knife. Similar to the tool of FIG. 1, the tool 20 of FIG. 2 is a stave with a four-faced rectangular sectional profile. The stave 20 differs from the previous embodiment in that the pivot journal means is arranged in the form of a pivot pin 21 that projects from an end of the stave 20, concentrically about the pivot axis S (wherein the latter also in this embodiment can form the center axis of the stave 20).
(17) Corresponding pivot pins can be formed in one or both ends 22, 23 of the stave 20.
(18) The stave 20 and the pivot pin 21 may be formed in one piece. The pivot pin 21 may alternatively be formed separately and afterwards inserted into the stave 20. A pivot pin 21 and a pinhole 15 may be applied in combination in the same stave. In use, the tool 10 or 20 interacts with a holder to form a tool assembly in a sharpening apparatus configured for simultaneous treatment of both sides of the edge of a knife.
(19) FIG. 3 is a partially broken away elevational view showing a tool and stave 10 or 20 pivotally mounted in a holder 30 of a first embodiment of the tool assembly. The stave 10 or 20 and the holder 30 form a tool assembly for a sharpening apparatus wherein two staves extend mutually overlapping at intersecting directions so as to form between them a V-shaped groove as is known per se, wherein a knife can be inserted and moved manually back and forth while in contact with treatment surfaces on the staves for simultaneous treatment of both sides the edge of a knife. The holder 30 is separable and includes a shaft 31 and a detachably mounted head 32. The holder parts 31, 32 can be joined together by either of a threaded connection 33, a snap-lock engagement, or through a form-fitting engagement between the parts 31 and 32, e.g.
(20) A pivot pin 34 is supported on the holder 30 and in mounted position received in a pinhole 15 in the end of the stave 10. In alternative way, a pivot pin 21 in the end of a stave 20 may be pivotally received in a pinhole formed in the opposite side of the head 32 of the holder, as indicated by dashed lines 21 in FIG. 3. In the drawing, a dashed line 35 indicates a third alternative for journaling the stave 10 in the holder, comprising a separate pivot pin 35 which can be inserted into a pinhole 15 in the end of the stave via a through-hole arranged in the head 32. In this latter embodiment, the head 32 may be permanently mounted or formed integrally with the shaft 31.
(21) FIG. 4 is a cross-sectional view through the arrangement of FIG. 3 taken along the line IV-IV in FIG. 3. FIG. 4 illustrates a pivot limit function which is realized in that adjacent corners h1 and h2 in the cross-sectional profile of the stave 10 or 20 are located at a distance r from the axis S which is longer than the shortest distance d from the axis S to the holder, in a plane transverse to the pivot axis S, such that said corners, or the intermediate face between the corners h1 and h2, will hit the holder to be stopped thereby when rotation reaches a limit for allowed pivoting within a restricted pivot angle range α. Chamfering 36, 37 may be applied to corners in that side of the shaft 31 which is facing the stave, to provide precise definition of the restricted pivot angle range α.
(22) As already mentioned, all corners of the staves 10 or 20 may be located on the same or substantially the same distance r from the pivot axis S, such that the pivot limit function is provided regardless of which side of a stave that is facing the holder in the mounted position, as long as the condition of r>d is met with.
(23) FIG. 5 illustrates journaling of the opposite end of a stave 10 or 20 in a lower part of the holder 30. In a way similar to the upper journal, a pivot pin 34 projects from the holder for engagement with a pinhole 15 mouthing in a lower end of the stave.
(24) Obviously, the holder 30 may alternatively be separable in a lower region of the shaft 31. It will be understood, that also the subject end of the stave may be journaled in the holder by means of a pivot pin 21 which protrudes from a stave 20 for insertion into a pinhole formed in the opposite side of the holder, as explained with reference to FIG. 3. The expressions upper and lower as used herein shall be understood as referring merely to the orientation of the subject elements in the drawings.
(25) As illustrated in FIGS. 6-8, the staves can have different sectional profiles having different numbers of corners and faces. For example, FIG. 6 shows a tool in the form of a stave having three faces and a triangular cross section. FIG. 7 shows a stave having four faces and a rectangular or square cross section, whereas FIG. 8 shows a stave having five faces and the cross-sectional shape of a pentagon. One singular stave can this way offer up to three, four or five surfaces effective for treatment of a knife edge.
(26) Accordingly, the tools 10, 20 are shaped as multi-faced staves which can be rotated upon journaling in the holder for proper selection of a face for treatment of a knife to be treated within the restricted pivot angle range.
(27) Although the staves shown in FIGS. 6-8 all have equilateral sectional shapes, this is not a requirement for providing the pivot limiting function or other advantages of the invention. Any triangular, rectangular and polygonal shape which meets the condition of r>d can be contemplated for implementation in the tool assembly.
(28) The four-faced embodiment with a rectangular section provides however a preferred combination of strength and utility, especially in ceramic tools. More precisely, the pointed corners of a triangular section would be more brittle and run higher risk of being damaged than the blunt corners of a rectangular section. On the other hand, the transversal width of faces and thus the effective treatment length of each face will be less in a five-faced embodiment than in the four-faced embodiment. The four-faced embodiment thus provides an advantageous combination of versatility, long service life/wear, and durability.
(29) FIGS. 6, 7 and 8 are also examples of tool assemblies wherein different embodiments of the stave-shaped tool may be included in combination with various designs of the holder.
(30) In FIGS. 9 and 10 a tool and stave 10 of rectangular sectional profile is shown in combination with an alternatively designed holder 40. The holder 40 is produced from a rod of circular section, the diameter of which is adapted to the diameter of a pinhole 15 in the end of the stave 10. The holder 40 can be formed from a straight bar which is in one end bent through 180° so as to form a pivot pin for insertion into the pinhole 15. In FIG. 9, the radius r and distance d demonstrate that the above said pivot limit function is implemented also in this embodiment of the tool assembly.
(31) FIG. 10 shows the mounting and journaling of the stave 10 in the holder 40. The holder 40 comprises a shaft 41 which by a first end 42 is secured in a slide or trolley 43 which can be movably arranged in a chassis (not shown) of a sharpening apparatus. The holder shaft 41 reaches upwards at slanting angle to a headend 44, the latter carrying a pivot pin 45 which engages a pinhole formed in an upper end of the stave 10. The opposite end of the stave comprises a second pinhole into which is inserted a pivot pin 46 that is biased from a spring 47, seated in the slide or trolley 43. The pivot pin 46 is this way biased in the direction of the pivot pin 45 at the headend of the holder, and with a biasing force sufficient to lift the stave 10 for journaling on the pivot pins 45 and 46.
(32) Alternatively, a spring biased pivot pin may instead be seated in an end of the stave, if appropriate.
(33) The holder 40 can form part of a tool assembly in a sharpening apparatus in which, in a way known per se, two or more tools are overlapping each other at intersecting directions in order to form between them a V-shaped groove into which a knife can be inserted to be moved manually back and forth while in contact with the effective surfaces of the tools for simultaneous treatment of both sides the edge of the knife.
(34) In the previous embodiments the tool is journaled in both of its ends. FIG. 11 illustrates a tool that is journaled in a holder 50 by one of its ends only. A stave 10 has a pinhole 51 mouthing in the lower end of the stave. The pinhole is inserted on a pivot pin 52 which reaches from an anchoring point in a holder member 53. In the inserted position, the stave is secured axially by means of a retainer spring 54 including a finger 55. In retaining mode, the finger 55 is slidingly hooked into a recess 56 formed in the outside of the stave. The finger 55 may be bent into arcuate or semi-circular shape, whereas the recess 56 may form a circular or semi-circular groove that reaches circumferentially, at least partially, around the stave 10. The finger 55 may have a length which corresponds to about half the circumference of the stave in order to facilitate a lateral insertion of the finger into the groove upon mounting. In a way similar to what has been disclosed above, a pivot limit function is provided through the interaction between corners or an intermediate face of the stave and a portion 57 of the holder, which reaches a distance upwards along the stave. Another embodiment is illustrated in FIGS. 12 and 13. With reference thereto, a tool and stave 10 or 20 is pivo tally journaled in a holder 60 by means of a pin and pinhole combination, here generally defined as reference number 61. More precisely, the stave is mounted in a moving holder member 62 which can slide back and forth in a stationary holder member 63. In mounted state the stave rises cantilevered from the moving holder member 62, at a slanting angle, through a slot 64 formed in the top of the stationary holder member 63. A rod 65 projects from an end of the movable holder member 62, the rod 65 reaching through a hole formed in a journaling element 66. The rod 65 carries a spring 67 which acts against the journaling element 66 to urge the movable holder member and stave towards an initial position, substantially as shown in the drawings. In side-by-side relation, a corresponding assembly is turned 180° to form, by the crosswise related staves, a groove V into which a knife blade can be inserted for treatment. Downwards pressure from the knife blade causes the staves and movable holder members 62 to move against the force of the respective springs 67, as indicated by the double-arrow in FIG. 13.
(35) A pivot limit function is accomplished by interaction between the holder 60 and the stave 10 or 20. More precisely, in the embodiment of FIGS. 12-13 the stave has a four-faced, rectangular sectional profile having a width w1 that is slightly less than the width w2 of the slot 64 in the top of the holder 60. The allowed pivot angle movement a is defined by the extreme positions at which either of the stave corners h1 or h2, in rotation about the axis S, hits the nearest wall of the slot 64 (as illustrated in dashed lines in FIG. 12). As in previous embodiments, accordingly, the corners h1, h2 are located at a distance r from the pivot axis S which is greater than the shortest distance d between the pivot axis S and the holder 60 in sectional view.
(36) In FIG. 12, the double-arrow a illustrates the pivot angle range a within which the staves can pivot about their axes S. The double-arrow a thus also indicates the amount to which a knife to be treated can deviate from an ideal straight path in the V-groove without losing area of contact with the treatment surfaces of the staves. Since the staves are journaled in their ends, pivotally about the pivot axes S passing through the staves internally of the faces of the staves, any one of the faces 14 is optionally available for treating a knife to be treated within the restricted pivot angle range α.
(37) The elemental geometrical shape of the tool or stave 10, 20, which is void of indications of fracture or other weaknesses, improves the resistance to failure in ceramic staves and sharpening tools made of other material. The non-complex shape of the stave facilitates a simple and efficient cleaning without any risk of dirt or particles that might accumulate in hard-to-access spots.
