SHARPENABLE EDGE SHARPENING EQUIPMENT

Abstract: Sharpening equipment in the form of sharpening device (10) comprises jaw fashion arranged gripping means (12) for gripping an item such as a knife (50) of which the blade requires sharpening, a sharpening means carrier in the form of a sharpening element holding base (14) releasably holding a sharpening stone (16), a guiding layout in the form of a guiding rod (18) mounted to reciprocate along an adjustably mounted support guide (20) in parallel with the sharpening surface (16.1) and an angle adjustment facility as provided by a connecting arm (24). The arm (24) extends integrally with respect to the gripping means (12) and is swivellably connected to the leading end of the rod (18). A disc (26) as mounted about the swivelling position presents a graduated dial providing face (28). The gripping means (12) is arranged to cause its central axis (46) to pass through the pivotal point (48) between the gripping means (12) and the rod (18).

Description: (1) TITLE OF THE INVENTION Sharpenable edge sharpening equipment (2) CROSS REFERENCED APPLICATIONS US 271 444 US 273 081 US 278 237 US 1 284 091 US 4 471 951 US 4 512 112 (3) BACKGROUND TO THE INVENTION In sharpening the blade of a knife or other similar equipment the acuteness of the sharpening angle often requires precision work. To achieve this the sharpening edge must be maintained at the same sharpening angle during the performance of a sharpening action. As the sharpening angle varies between equipment such as between knives or scissors chisels etc the correct sharpening angle must be selected prior to sharpening such equipment. The object of this invention is thus to provide a device that can maintain the selected sharpening angle throughout a sharpening session while enable selection of the desired sharpening angle prior to commencing with a sharpening action. (4) FIELD OF THE INVENTION This invention relates to sharpening equipment for sharpening a sharpenable edge of appropriate items and to a sharpening set assemblable into the sharpening equipment. 2 (5) PRIOR ART DESCRIPTION Knife sharpening devices are known in the art. According to one arrangement a sharpening stone is recirpocable mounted by way of a rod to be moved over the edge of an article desired to be sharpened. To accommodate various sharpening angles the device provides a number of reciprocating apertures spaced in series along a formation. The rod is fitted along the aperture that results in the sharpening angle nearest to that required. (US 4 512 112) (6) SUMMARY OF THE INVENTION According to the invention there is provided sharpening equipment for sharpening a sharpenable edge of appropriate items such as knives, scissors, chisels or the like. (7) BRIEF DESCRIPTION OF THE DRAWING The invention is hereafter described, by way of example, with reference to the accompanying drawings. In the drawings Figure 1 shows sharpening equipment in the form of a sharpening device for sharpening a sharpenable edge as found on an appropriate item such as a knife, scissors, a plane cutter or the like, in side elevation as set for sharpening an item of which the sharpenable edge is steeply bevelled, as in the case of the blade of a knife, Figure 2 shows the device as set according to figure 1 , in plan view, Figure 3 shows the device as set for sharpening an item with a less steeply bevelled sharpenable edge such as a pair of scissors, in side elevation, Figure 4 shows the device as adapted into clamping fashion holding an appropriate item such as a chisel, in side elevation, 3 Figure 5 shows the device as readjusted into sharpening a serratedly or like edged item such as a knife with a serrated cutting edge, in side elevation, Figure 6 shows in detail the gripping means of the device as incorporating the angle adjustment facility, Figure 7 shows the device along the view A-A in figures 1 , 3 and 4, Figure 8 shows the base of the device as fitted with upstanding sharpening stones after removal of the guiding layout and the gripping means, and Figure 9 shows a conventional serrated edge sharpening element used when the device is readjusted according to figure 5. (8) DETAILED DESCRIPTION OF THE DRAWINGS Referring to figures 1 to 5 of the drawings, sharpening equipment in the form of sharpening device, is generally indicated by reference numeral 10. The device 10 comprises gripping means generally indicated by reference numeral 12, a sharpening means carrier in the form of sharpening element holder as provided by a sharpening element holding base 14 releasably holding a sharpening element in the form of a sharpening stone 16, a guiding layout arranged to perform a sharpening session at a constant sharpening angle in the form of a guiding arm as provided by a guiding rod 18 mounted to reciprocate along an aperture in an adjustably mounted support guide 20 in parallel with the sharpening surface 16.1 of the sharpening stone 16 in response to retaining equal corresponding inner angles 22, and an angle adjustment facility in the form of a swivelling mechanism forming the connection between the rod 18 and the gripping means 12 as provided by an connecting arm 24 extending integrally with respect to the gripping means 12 and being swivellably connected to the leading end of the rod 18 via a disc 26 4 fitted to the rod 18 via a socket 27 with the disc presenting a graduated dial providing face 28 against which the leading end of the arm 24 sweeps dial fashion. Referring to figures 1 to 3 and also to figure 5 the gripping means 12 is provided a jaw fashion assembly 30 comprising an upper jaw 32 extending into the arm 24 and a lower jaw 34. An item of which the cutting edge requires sharpening is gripping fashion receivable in the pinching zone 36 defined between the jaws 32, 34. Such item is securely so held in response the tightening of a tightenable element 40 engaging screw fashion between the jaws 32, 34. To enhance the gripping effect an adjustment element 42 situated towards the rear ends of the jaws 32, 34 engages screw fashion with the jaw 32 while urging with its inner end against the inner wall of the jaw 34 as suitably recessed to limit relative adjacent movement of the jaws 32, 34. The jaws are retained apart even if not holding an item by means of a spring 44 fitted onto the element 40 between the jaws 32, 34. The assembly 30 is arranged to cause its central axis 46 to pass through the pivotal point 48 between the gripping means and the rod 18 in response to the suitable formation of the connecting arm 24. Once an item is thus pinched in the zone 36 the axis 46 passes along its cutting edge. Referring particularly to figures 1 and 2 a knife 50 is normally held at a relatively small inner angle 22 to result in the one face 50.1 of its leading edge 50.2 lying flush against the sharpening surface 16.1 as its cutting edge bevelling angle is steep. As more clearly shown in figure 2 the knife 50 is pinched in the pinching zone along its blunt edge 50.3. When the cutting edge bevelling angle is not so steep, as shown in the case of scissors 52 in figure 3, the angles 22 require adjustment, as discussed below, to retain the leading edge face 52.1 requiring sharpening in contact with the sharpening surface 16.1. In the case where the item of which the sharpenable edge requires sharpening carries a shape that cannot fit the embodiment of the gripping means 12 as discussed in figures 1 to 3 and 5, the gripping means 12 permits adaptation into forming a clamp 54 as shown in figure 4. To achieve this the lower jaw 34 is removed by removal of the elements 40 and 42. The jaw 32 presents adjacent engaging apertures 56 (as seen in figure 2) engageable by means of wing nuts 58 used for securing a clamp formation 60 to the inner surface of the jaw 32. The clamp formation 60 is thus used to clamp an appropriate item, such as a chisel 62, to the gripping means 12 by way of gripping it to the inner surface of the jaw 32. When so clamped its handle 64 extends alongside the disc 26. As the leading portion of the chisel 62 is still located in the zone which defines the pinching zone in the case of the figures 1 to 3 embodiment the chisel 62 will still lie along an axis 66 that passes through the pivotal point 48. As discussed above in referring to figures 1 to 4, desired sharpening depends on the relevant face of the leading edge of a sharpenable item lying flush against the sharpening surface 16.1. To accommodate a large variety of cutting edge bevels the guiding layout in conjunction with the swivelling mechanism is thus formed to accommodate an infinite variety of bevels within the range of the device 10. Once the sharpening angle of a cutting edge is established, the appropriate angle is set by pivoting the arm 24 relative to the rod 18 around the pivoting point 48 until the dial as defined by the end of the arm 24 ending appropriately indicating the relevant angle on the face 28. Once this is set the arm 24 is locked to the disc 26 by means of a pinching screw 29 pinching fashion holding the arm 24 and disc 26 at their desired setting. An adjustment from a setting as, for example, shown in figure 1 to that of figure 3 or figure 4 will, however, also require re-setting of the rod 18 to retain a parallel relationship between the rod 18 and the sharpening surface 16.1 for causing the inner angles 22 to be the same for achieving the desired sharpening effect. To this effect the guide 20 is thus adjustably mounted to a support formation in the form of a rail 68 and held in the appropriate position by means of a grub screw 70 releasably locking the guide 20 to the rail 68. The guide 20 is thus adjusted until the rod 18 again lies parallel to the sharpening surface 16.1 , which will cause the angles 22 to be the same again. To promote attainment of the parallel relationship, the device 10 is fitted with a correlator in the form of a linear member as provided by the handle portion 70.1 of the screw 70 which extends in parallel with the sharpening surface 16.1 once the screw 70 is fitted to the guide 20. Sharpening is achieved by to-and-fro movement of the sharpenable edge of the appropriate item over the sharpening surface 16.1 in the direction of arrow 72. This is done by manual displacement of the gripping means 12 while urging it to the desired extent against the 6 surface 16.1. It will be appreciated that sharpening is often desired to be carried through by way of uni-directional stroke. To this effect and referring to figure 7 the rod 18 passes with some vertical play along the aperture 74. As lateral movement of a cutting edge over the sharpening surface 16.1 is also often desired the aperture 74 has an oblong horizontal profile thus enabling lateral play of the rod 18 in the aperture 74 as well. To permit a replacement or turning around of the sharpening stone 16 it fits removably to the base 14. The base 14 makes provision for filmy holding the stone 16 in position once fitted to thereto by means of a seat 75 into which the stone is locked via a locking plate 77 as secured to the base 14 by means of a wing nut 79. The stone 16 is often required to be replaced during a sharpening action to pass though a procedure requiring stones of different grits. In use according to the figures 1 to 4 embodiments, an object of which an edge is desired to be sharpened is thus secured to the gripping means 12, the desired angle selected on the dial and the support guide 20 locked to the rail 68 in a rod 18 to sharpening surface 16.1 parallel relationship. Sharpening is achieved by desirably sweeping the sharpenable edge over the surface 16.1. Once the one side of the sharpenable edge has been desirably sharpened the gripping means 12 is simply swivelled though 180 degrees owing to the threaded engagement of the rod 18 to the disc 26 and the procedure repeated for the opposite side. While the embodiments of the invention discussed with reference to figures 1 to 4 are ideal for sharpening a sharpenable edge extending at least substantially linearly, the sharpening of a serrated, scalloped or saw toothed edge requires a separate sharpening action. This can in practise only be effectively achieved by displacement of the sharpening element while the item presenting such edge is retained stationary. To this effect and referring to figures 5 and 9 the device 10 permits the replacement of the disc 26 and the gripping means 12 by a conventional sharpening element 76 for use in conjunction with not-linear edges, as shown in more detail in figure 9. Disengagement is achieved by the leading end of the rod 18 fitting screw fashion into the socket 27 fast with 7 the disc 26. The sharpening element 76 is fitted with a socket by means of which it engages screw fashion with the rod 18. To bring the item of which the non-linear edge requires sharpening into a sharpening relationship with the element 76 it is again gripped in the pinching zone 36 of the gripping means 12 as now fitted to the bottom end of the rail 68. The rail 68 is thus releasably secured to the base 14 by being screw fashion received in a threaded socket in the base 14 and so locked by means of a wing nut 80. An indication of the sharpening angle is achieved by the rail 68 presenting graduated markings 82 that indicate the sharpening angle 84 for as long as the gripping means 12 extends transverse to the rail 68. As the rod 18 in this case does not reciprocate transverse to the rail 68, the guide 20 provides a desiredly shaped aperture 84, as shown in figure 7 in a wing 20.1 which has an oblong shape in the direction of the rail 68 while also permitting lateral play to attend to adjacent serrations or the like. While specialised sharpening by means of the device 10 is often only required at spaced intervals, regular touching up is often required when, for example, a knife is used in an ongoing fashion. To this effect and referring to figure 8 the base 14 is fitted with spaced threaded apertures (not shown) into which conventional sharpening stones 86 are receivable after removal of the guiding layout and the gripping means 12. While the invention deals with a device 10 which is constituted from various members the invention also extends to a set constituting the gripping means 12 as fitted with the disc 26, the holding base 14, a sharpening stone 16, the guiding rod 18, the support 20, the rail 68. The set can also include the sharpening element 76 and the sharpening stones 86.

Claims: δ (9) CLAIMS (1 ) Sharpening equipment for sharpening a sharpenable edge of appropriate items comprising, gripping means arranged to firmly though releasably grip such item, a sharpening means carrier by means of which sharpening means as providing a sharpening surface is carried and against which the sharpenable edge of such item as held by the gripping means is sharpening fashion moveable in response to relative movement between the gripping means and the carrier once the equipment is operatively used, a guiding layout arranged to at least effectively maintain a sharpening angle as formed between the sharpenable edge of such item once held by the gripping means and such sharpening member as held by the holding facility at a pre-set value during a sharpening action while permitting urging the gripping means as holding such item and the carrier as holding such member against one another during a sharpening session to an extent to successfully perform a sharpening function, and an angle adjustment facility for adjustably setting the sharpening angle between the gripping means and the carrier enabling the sharpening of a sharpenable edge at a desired angle, the guiding layout in the appropriate case making provision for a compensating adjustment to ensure that the desired sharpening effect is maintained in response to a change in the sharpening angle by way of the angle adjustment facility. (2) Sharpening equipment as claimed in claim 1 in which the angle adjustment facility provides for sharpening angle indicating fashion-enabling adjustment of the sharpening angle thereby to sharpen a sharpenable edge at the desired angle. (3) Sharpening equipment as claimed in claim 1 or claim 2 which is arranged to cause one of the carrier and gripping means to remain stationary during the performance of a sharpening action. (4) Sharpening equipment as claimed in any one of the preceding claims in which the angle adjustment facility makes provision for adjustment of the sharpening angle in response to swivelling of the gripping means, as extending away from a pivotal position, with respect to the carrier (5) Sharpening equipment as claimed in any one of the preceding claims in which the gripping means is constituted to adequately firmly jaw fashion hold an appropriate item to cause the central axis along the gripping means to pass at least substantially along the sharpening edge of such item, once so held, thus maintaining such item at the desired angle with respect to the sharpening means as carried by the carrier once the equipment is in use. (6) Sharpening equipment as claimed in claim 5 in which the gripping means is adaptable to form a clamp for clamp fashion holding an appropriate item in such a way that the central axis of the gripping means passes at least in close vicinity parallel relationship adjacent the sharpening edge of such item once held, if not there along, thus maintaining such item at the desired angle with respect to the sharpening surface of a sharpening element (7) Sharpening equipment as claimed in any one of the preceding claims in which the guiding layout makes provision for moving the gripping means and the carrier apart thereby to separate such sharpenable edge from such sharpening member during a sharpening session, if desired. (8) Sharpening equipment as claimed in claim 7 in which the earner and the gripping means are relatively movable to one another owing to the guiding layout being arranged to guidably enable relative at least reciprocable manually performable motion between them in response to manually holding the appropriate one of the carrier and the gripping means as respectively holding a sharpening element and an item presenting a sharpenable edge, separation of the gripping means and the holding facility during a sharpening session, if 10 desired, enabling their relative repositioning with the guiding layout also making provision for adjustment, in conjunction with the angle adjustment facility, to accommodate a variety of sharpening angles in a way that maintains the desired sharpening effect. (9) Sharpening equipment as claimed in claim 8 in which the sharpening means carrier is in the form of sharpening element holder for securely holding a sharpening element against which the sharpenable edge of an appropriate item is reciprocably sharpening fashion movable on operatively using the equipment (10) Sharpening equipment as claimed in claim 8 or claim 9 in which the sharpening element holder is in the form of a stationary sharpening element holding base releasably holding such element in a sharpening surface upward facing fashion to enable an overhead sharpening action by way of reciprocable gripping means movement once holding an item presenting a sharpenable edge, the guiding layout making provision for promoting a parallel sweeping action between such sharpenable edge and such element while enabling compensating adjustment to ensure that the desired sharpening effect is maintained in response to a change in the sharpening angle by way of the angle adjustment facility (11 ) Sharpening equipment as claimed in claim 10 in which the angle adjustment facility is in the form of a swivelling mechanism by means of which the angle formed between the gripping means as holding a sharpenable item and the sharpening face of a sharpening element as held by the holding base is adjustable (12) Sharpening equipment as claimed in claim 11 in which the swivelling mechanism incorporates a sharpening angle indicator showing the magnitude of a sharpening angle selected (13) Sharpening equipment as claimed in claim 12 in which the sharpening angle indicator is in the form of a graduated dial against which a pointer as extending along the central axis of the pinching means is movable 1 1 (14) Sharpening equipment as claimed in any one of claims 11 to 13 in which the guiding layout includes an at least reciprocably movable guide arm at the leading end of which it swivellably connects to the gripping means via the swivelling mechanism with the guide member being supported along a support guide that is re-lockably spaceably adjustably mounted with respect to the base thereby to reposition the guide member in response to an adjustment of the swivelling mechanism for maintaining a parallel reciprocating movement relationship between the guide member and the sharpening face of a sharpening element as held by the base as reflected by maintaining equal corresponding angles between the axis of the gripping means and the guide arm, on the one hand, and the sharpening surface of a sharpening element, on the other hand, once the equipment is in use (15) Sharpening equipment as claimed in claim 14 in which the guide arm is in the form of a guide rod passing reciprocably along an aperture in the support guide with the guide rod being of adequate length to perform a sharpening stroke along an effective length of the sharpening face of a sharpening member once the equipment is ready for operative used (16) Sharpening equipment as claimed in claim 14 or claim 15 in which the support guide is spaceably adjustably mounted with respect to the base by being slidably displaceably mounted along a support formation secured to and extending suitably away from the base (17) Sharpening equipment as claimed in claim 15 or claim 16 in which the guide rod passes with adequate play along the support guide to at least permit a degree of toggling action in a plane transverse to the base thereby providing moving the gripping means and the carrier apart by way of lifting an item as held by the gripping means from a sharpening surface once the equipment is in use thus also facilitating a uni-directional sharpening action. (18) Sharpening equipment as claimed in claim 17 in which the guide rod also passes with lateral play along the support guide thus enabling a lateral as well a reciprocating sharpening action. (19) Sharpening equipment as claimed in any one of claims 15 to 18 which is fitted with a sharpening stroke αirectioπ correlator against which movement of the guide rod is correlated in promoting its parallel relationship with the sharpening surface of a sharpening member on performing its reciprocable motion during operative use of the equipment. (20) Sharpening equipment as claimed in claim 19 in which the correlator is in the from of a linear member extending parallel to the sharpening face of a sharpening element, once fitted to the base, from the support guide and thus in near adjacent relationship with the guide rod. (21 ) Sharpening equipment as claimed in any one of claims 15 to 20 which makes provision for also, amongst others, sharpening a serrated or other similar non-linear sharpenable edge as carried by an appropriate item by permitting the replacement of the adjustable swivelling mechanism as releasably located at the leading end of the guide rod, by a conventional serrated edge or the like sharpening element while making provision for firmly holding such item in a sharpening relationship with respect to such element once fitted to the guide rod resulting in a serrated or the like edge sharpening element reciprocable sharpening action in response to reciprocation of the guide rod over the sharpenable edge of such item as stationary held, the support guide in the appropriate case also making provision for adequate play in the plane of reciprocation of the rod as extending transverse to the serrated edge of an appropriate item once operatively held to accommodate an item held in a way in which the slant of adjacent sharpenable edge sections as extending along its sharpenable edge requires a reciprocating displacement at an acute inner with respect to the support formation to perform the desired sharpening action. (22) Sharpening equipment as claimed 21 which makes provision for firmly holding a serrated or the like edged item desired to be sharpened by way of the gripping means as also being attachable to the support formation once released from the guide rod. (23) Sharpening equipment as claimed 22 in which the support formation presents a sharpening angle graduation there along indicating the sharpening angle of the guide rod, as carrying a serrated or the like edge sharpening element, with respect to a correspondingly edged item when held to extend transverse to the support formation. (24) A sharpening equipment set assemblage into sharpening equipment for sharpening a sharpenable edge of an appropriate item comprising, gripping means arranged to firmly though releasably grip such item, a sharpening means carrier by means of which sharpening means as providing a sharpening surface is carried and against which the sharpenable edge of such item as held by the gripping means is sharpening fashion moveable in response to relative movement between the gripping means and the carrier once such equipment as assembled from the set is in operative use, a guiding layout arranged to at least effectively maintain a sharpening angle as formed between the sharpenable edge of such item once held by the gripping means and such sharpening member as held by the holding facility at a pre-set value during a sharpening action while permitting urging the gripping means as holding such item and the carrier as holding such member against one another during the performance of a sharpening session to an extent of successfully performing the sharpening action once such equipment is in use, and an angle adjustment facility for adjusting the sharpening angle between the gripping means and the carrier once such equipment is so assembled from the set enabling the sharpening of a sharpenable edge at a desired angle, the guiding layout once the set is formed into such equipment in the appropriate case making provision for a compensating adjustment to ensure that the desired sharpening effect is maintained in response to a change in the sharpening angle by way of the angle adjustment facility. (25) A sharpening equipment set assemblage into sharpening equipment as claimed in any one of claims 2 to 23. (26) Sharpening equipment substantially as described with reference to the accompanying drawings. 14 (27) A sharpening equipment set substantially as described with reference to the accompanying drawings. (28) Sharpening equipment whenever assembled from a sharpening equipment set as claimed in claims 24, 25 or 27.

Inventors: PRETORIUS HEINRICH STIEGER, PRETORIUS STEPHAN DEON, PRETORIUS, HEINRICH, STIEGER, PRETORIUS, STEPHAN, DEON
Applicants: PRETORIUS HEINRICH STIEGER, PRETORIUS STEPHAN DEON, PRETORIUS, HEINRICH, STIEGER, PRETORIUS, STEPHAN, DEON
Application year: 1999
Main classification: B24D15
IPC codes: B24D15