EDGE TREATMENT APPARATUS WITH RECIPROCATING TREATMENT SURFACES

Abstract

An apparatus for the treatment of cutting edges includes a first and second tools each having treatment surfaces. The treatment surfaces are arranged to define a V-shaped groove for receiving a cutting tool to be sharpened. The tools are driven by a main shaft and are connected to the main shaft via eccentric bodies rotationally fixed on the main shaft, connecting rods attached to the eccentric bodies, and auxiliary shafts connecting the connecting rods to the first and second tools. A power unit is configured to rotate the main shaft, wherein rotation of the main shaft causes the first and second tools to reciprocate up and down relative to the main shaft.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a U.S. National Phase of PCT Application No. PCT/SE2021/050332 filed Apr. 12, 2021, which claims priority to Sweden Patent Application No. 2030123-0 filed Apr. 13, 2020, the disclosures of which are hereby incorporated in their entirety by reference herein.

TECHNICAL FIELD

The present disclosure relates to an apparatus for the treatment of cutting edges, such as knives edges, by simultaneous treatment of both sides of a cutting edge. In the type of apparatuses referred to, oppositely arranged sets of treatment surfaces are effective for restoring and sharpening a cutting edge by grinding, honing, polishing or edge straightening treatments. Particularly, the disclosure relates to an apparatus wherein the treatment surfaces are driven back and forth in a reciprocating motion during treatment.

BACKGROUND

WO2009134193(A1) discloses a set of treatment surfaces accommodated in each of two oppositely arranged blocks respectively, wherein the blocks are commonly arranged in a holder. The holder rests from above against a cam wheel which lifts and lowers the holder and the blocks with the treatment surfaces altogether in a reciprocating vertical motion as the cam wheel rotates. A manually applied downwards pressure via the knife towards the treatment surfaces is required in order to maintain the holder into contact with the cam wheel so as to follow the cam wheel in the lifting and lowering motions.

U.S. Pat. No. 2,024,860(A) discloses two sets of convexly arcuate treatment surfaces arranged in a pair of mutually opposite blocks, wherein each block is pivotally supported on a pivot pin. A pivoting motion of the blocks is powered electromechanically by a wire coil and iron core combination that causes the blocks to swing alternatingly upwards or downwards as the coil is fed with current.

A downside of the first mentioned apparatus is that it sets up high demands for the journal of the treatment surfaces within the blocks since the treatment surfaces must be able to adjust themselves horizontally in synchronization with the vertical movements of the blocks. Another downside is that the motion is dependent on a manually applied downward force via the knife to bring the holder into contact with the cam wheel to achieve the reciprocating motion.

A downside of the second mentioned apparatus is that it results in a cutting edge having concavely arcuate faces that renders the outermost portion of the edge very thin and susceptible to undue wear and deformation.

A third apparatus for treatment of cutting edges is disclosed in U.S. Pat. No. 4,528,777(A). This apparatus includes a pair of assemblies arranged at intersecting inclinations, each assembly having a cylindric honing piece that is moving back and forth in axial directions while continuously rotating. The motions are driven by connecting rods that are journaled at an eccentric position on rotating wheels.

A disadvantage connected with the third apparatus is that the assemblies are supported pivotally about the centres of the wheels, causing variation in the inclination of the honing pieces relative to the knife in dependence on the depth of insertion of the knife between the honing pieces. Besides, the inclinations of the honing pieces are solely decided through physical contact with the knife, the honing pieces thus following slavishly and confirming any present inaccuracy in the knife's edge.

SUMMARY

The present disclosure provides an apparatus for the simultaneous treatment of both sides of a cutting edge by reciprocating treatment surfaces, wherein the apparatus is set up for solving the problems mentioned above in connection with previously known apparatuses having movable treatment surfaces or honing pieces.

According to one aspect of this disclosure, an apparatus for treatment of cutting edges includes treatment surfaces that move back and forth at intersecting inclinations, wherein the intersecting angle between the treatment surfaces remains the same independently of the depth of insertion of the knife between the treatment surfaces.

According to another aspect of this disclosure, an apparatus for treatment of cutting edges includes treatment surfaces that move back and forth at intersecting inclinations, wherein frictional forces and pressure applied by the treatment surfaces towards the opposite sides of the knife outbalance each other in operation, so that no downward force is required to manually hold the knife at any depth of insertion of the knife blade between the treatment surfaces.

According to yet another aspect of this disclosure, an apparatus for treatment of cutting edges includes treatment surfaces moving back and forth at intersecting inclinations, wherein the apparatus is designed for modular extension that permits combinations of edge angles and/or different kinds of treatments of a cutting edge.

One or several of these aspects are met in an example apparatus for treatment of cutting edges, the apparatus includes a first tool supporting a first set of treatment surfaces each having an axial length oriented at crosswise relation to a second set of corresponding treatment surfaces supported in an oppositely arranged second tool, such that the treatment surfaces form in combination the sides of a V-shaped groove with an opening angle determined by the intermediate angle between the first and second sets of treatment surfaces. The first and second tools are individually connected with a main shaft by connecting rods driven in rotation by a power unit. One end of the connecting rod is pivotally connected to the associated tool whereas the opposite end of the connecting rod is pivotally connected to the main shaft via an eccentric that is rotationally journaled in the end of the connecting rod. The eccentric is a cylindrical body through which the main shaft passes non-rotationally at an eccentric position between the centre and the periphery of the eccentric. In a set of first and second tools, the appurtenant eccentrics are mutually rotated and angularly displaced on the main shaft. Each tool and associated connecting rod are indirectly connected by an auxiliary shaft that runs in parallel with the main shaft, wherein the connecting rod is pivotally journaled on the auxiliary shaft whereas the tool is journaled on the auxiliary shaft for sliding movement in the length direction of the auxiliary shaft.

Together with the tool, which is journaled to slide thereon, the auxiliary shaft is arranged to move freely in the vertical direction transversely to the length of the auxiliary shaft. In result, as a technical effect provided by this arrangement, the tools and treatment surfaces have linear mobility in diagonal directions including a horizontal and a vertical directional component, respectively.

In other words, the first and second tools are set in motion by a power transmission that alternatingly lifts and lowers the tools such that the first tool is lifted as the second tool is lowered and vice versa. An advantage and technical effect provided by this arrangement is that frictional forces and pressure applied towards opposite sides of the knife will balance each other out such that no extra force is required to manually hold the knife at a desired depth of insertion in the V-shaped groove.

The apparatus further includes) guides that are arranged and effective for controlling the motion of the tools such that the first and second sets of treatment surfaces supported in the tools are alternatingly moved back and forth in the length directions of the treatment surfaces. In other words, the first and second tools are controlled by the guides that are oriented at directions which are mainly in parallel with the orientations and inclinations of the associated treatment surfaces.

In one embodiment, the first and second tools are each supported on guide rods that are received for axial movement in guide tubes that are arranged one each in each opposite side of a tool. An advantage and technical effect with this embodiment is that the guides can be kept clean and protected from grinding dust that may form during grinding or other treatment of a cutting edge.

The tools may be arranged as compartmentalized houses defining cells that are open in a forward or proximal end of the tool (i.e., the end facing the opposite tool). In such an embodiment, the cells are arranged for accommodation of holder members each of which carries a treatment surface in the forward end of the holder. In ways similar to what is previously described in Applicant's WO2015030655(A1), the holders may be arranged movable in the cells and acted upon by springs arranged and effective for urging the holders and treatment surfaces in the proximal direction, this way exerting elastic contact pressure against the knife during treatment.

It will be understood that lowering the knife deeper into the V-groove will cause the holders to retract further into the cells of the tool against the force of the biasing springs. In the reverse, lifting the knife in the V-groove will allow the holders to follow, driven by spring force in the proximal direction. In this connection it serves again to explain that the intermediate angle between the legs of the V-shaped groove, in other words, the angle of contact between treatment surfaces and knife remains unchanged independently of the depth of insertion of the knife.

As each treatment surface is linearly straight in its length direction, the treatment results in a cutting edge having planar sides, which is advantageous from a strength point of view.

Since in treatment the knife is moved in its length direction between treatment surfaces in order to process the entire length of the cutting edge, each treatment surface advantageously includes a planar or convexly shaped front face when seen in cross sectional view. A planar front face may result in better efficiency and distribution of wear over the entire treatment surface, and thus a longer service life for treatment surfaces.

In use, the present arrangement of an apparatus for treatment of cutting edges provides distribution of wear of treatment surfaces over the entire length of the treatment surfaces.

Additional details and alternative embodiments of the invention will appear clearer from the detailed description given below and from subordinated claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a partially sectioned elevational view showing an apparatus for treatment of cutting edges according to the invention.

FIG. 2 shows a tool included in the apparatus of FIG. 1 on a larger scale, sectioned along the laterally displaced sectional planes IIa and IIb of FIG. 3.

FIG. 3 shows the proximal end of the tool of FIG. 2.

FIG. 4a shows a connection rod and eccentric that form parts of a power transmission included in the apparatus of FIGS. 1-3 in elevational view.

FIG. 4b shows the connection rod and eccentric of FIG. 4a in sectional view along the sectional plane IVb in FIG. 4a.

FIG. 5a shows a mounting arrangement of an auxiliary shaft and abutments forming parts of the power transmission included in the apparatus of FIGS. 1-3, in elevational view.

FIG. 5b shows the mounting arrangement of FIG. 5a in sectional view along the sectional plane Vb in FIG. 5a.

FIG. 6 is a partially sectioned top view of the apparatus of FIG. 1.

DETAILED DESCRIPTION

As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention that may be embodied in various and alternative forms. The figures are not necessarily to scale; some features may be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the present invention.

The invention is not to be limited to illustrated dimensions, angles or angle ranges, and that other angles and dimensions can be applicable and preferred in specific implementations. It also serves to point out that references to the horizontal and vertical direction/orientation are only used for illustrating purposes in order to facilitate disclosure, although in most cases, the apparatus will be positioned as described and illustrated, and placed on a flat horizontal surface in use.

With reference to the drawings, an apparatus for simultaneous treatment of both sides of a cutting edge includes at least one set of tools comprising a first tool 1 and an oppositely positioned second tool 2. Each tool 1 or 2 accommodates one or more treatment surfaces 3 and 4 respectively. The treatment surfaces 3 and 4 each includes a face that is effective for treatment of a cutting edge through any of grinding, honing or polishing, for example. The treatment surfaces can be realized in the form of coatings of hard metal or mineral grains such as diamond or rock, and may alternatively consist of ceramic material. The treatment surfaces 3, 4 can be applied to the exterior of an elongate and rod-shaped carrier member, and may alternatively constitute the very external face of a homogenous rod member.

The treatment surfaces 3 and 4 are thus elongate in shape and are, in the apparatus, arranged standing at a slanting orientation with respect to an imaginary vertical line VL, see the double-arrow L in FIG. 1. In an apparatus for simultaneous treatment of both sides of a cutting edge, the treatment surfaces are oriented at an inclination a from the vertical line VL such that opposite sets of treatment surfaces 3 and 4 form together a V-shaped groove with an intermediate angle 2α between the legs of the V, the vertical line VL forming the bisector to the V. Since the treatment surfaces are straight and linear in the length direction L, the V-groove will be defined through planar sides when seen from the end of the groove (as in FIG. 1). The intermediate angle of the V-groove will determine the edge angle of a treated cutting edge. The angle a may thus advantageously amount to an angular range of 12.5°-17.5°, resulting in an edge angle of 25°-35°. Other V angles may of course be applied as desired.

The tools 1 and 2 are supported on guides 5 (also known as guide members) for reciprocating movement, back and forth, in directions D which are inclined and diagonal with respect to the vertical, see the double-arrow D in FIG. 1.

In the left-hand set of tools illustrated in FIG. 1, the tools 1 and 2 are halted in a neutral or half-way position at which the tools 1 and 2 are set at equal heights, whereas the right-hand set of tools are halted in displaced positions at which the first tool 1 is lifted while the second tool 2 is lowered in the diagonal directions D.

The movements D are inclined at angles with respect to the vertical VL which are equal to the inclinations a of the treatment surfaces 3 and 4. In other words, the movements D are parallel to the length directions L of the treatment surfaces.

In the illustrated embodiment, the guides 5 include a guide rod 6 which is received for axial sliding movement in a guide tube 7, the latter being arranged or formed in the side face of the tool. A corresponding combination of guide rod and guide tube is arranged on each opposite sides of the tools 1 and 2 respectively. The guide rods 6 may be firmly anchored in a base 8 of the apparatus as indicated in FIGS. 1 and 2.

However, the invention need not be limited to the illustrated configuration. For example, linear guides for a forced diagonal motion control of tools may be realized in other ways, such as in the form of trackers running in grooves formed in the exterior of the tools (not illustrated).

The tools 1 and 2 are driven in reciprocating motion by a power unit 9 and a power transmission 10. A power unit 9 may be supplied in the form of an electrically or pneumatically actuated motor.

The power transmission includes a main shaft 11 that is driven in rotation by the power unit 9. The tools 1 and 2 are each operatively connected to the main shaft 11 by a connecting rod 12 and an eccentric 13 respectively, the latter being non-rotationally secured to the main shaft 11. Securing the eccentric non-rotationally on the main shaft can be achieved in several ways; for example, as indicated in FIG. 4b, a locking screw 35 is screwed into the eccentric 13 until the end of the screw 35 meets a flattened portion of the main shaft 11.

The eccentric 13 is a cylindrical body through which the main shaft 11 extends non-rotationally at an eccentric position. That is, at a position located between the centre EC and the periphery EP of the cylindrical body. In the embodiment of FIG. 1, the eccentric 13 associated with one of the tools 1 is angularly displaced at 180°, i.e., rotated by one half revolution, with respect to the angular position of the eccentric 13 associated with the other and opposite tool 2. This relation is illustrated by the right-hand set of tools in FIG. 1, wherein the major portion of the left eccentric is above the main shaft 11, whereas the major portion of the right eccentric is below the main shaft 11.

The eccentrics 13 are thus mutually angularly displaced on the main shaft 11, i.e., the eccentric 13 of the first tool 1 is rotated about the main shaft with respect to the eccentric 13 of the second tool 2. In result, the tools 1 and 2 will move in opposite directions when the main shaft 11 is rotated, such that one tool is lifted while the other tool is lowered and vice versa. If the angular displacement between the eccentrics is set at 90° or 270° clockwise or counterclockwise, e.g., the tools 1 and 2 will travel in the same movement direction, lifting or lowering, for half the total length of their potential travel, until one of the tools changes its movement direction. The closer the angular displacement gets to 180°, or one-half revolution, the shorter becomes the distance of common movement. Accordingly, at an angular displacement of 180°, the tools will shift movement directions simultaneously.

It is believed that an angular displacement of 180° between the eccentrics 13 of the first and second tools 1 and 2 provides the best mode of operation since it effectively out-balances the frictional forces acting on the knife in a treatment operation. However, the operator can still benefit from other advantages provided by the invention, such as the reciprocating linear motion of the treatment surfaces in the angular plane of the knife edge, also when the angular displacement is other than 180°, such as within the range of 90° to 270°, for example.

The eccentric 13 is journaled for rotation in one end of the connecting rod 12. A bearing 14 may be inserted between the eccentric and the connecting rod, if appropriate. The bearing 14 may be, for example, a roller bearing, e.g., a ball bearing or needle bearing, or a slide bearing in the form of a cylindric sleeve made of self-lubricating metal or synthetic material. A locking washer 15 may be used to keep the eccentric 13 seated in the connecting rod 12.

The opposite end of the connecting rod 12 is pivotally connected indirectly to the associated tool 1 or 2. For example, the connecting rod 12 is pivotally journaled on an auxiliary shaft 16 that runs in parallel with the main shaft 11. The appurtenant tool 1 or 2 is journaled onto the auxiliary shaft 16 for sliding movement in the length direction of the auxiliary shaft, i.e., in the horizontal direction H shown in FIG. 1. To this purpose, the auxiliary shaft 16 is slidingly journaled in a through passage that is formed in a link member 17, depending from the lower end of the tool 1 or 2.

One end of the auxiliary shaft 16 protrudes from the passage in the link member 17 to provide a shaft length for pivotal connection of the connecting rod 12. The protruding opposite end of the auxiliary shaft 16 carries a radial extension, such as a flange or a head 18, which prevents the auxiliary shaft from sliding out of the through passage in the link member 17.

However, the auxiliary shaft 16 may be axially movable within limits set by abutments provided in the apparatus. A stationary element 19 provides a first abutment 19 onto which the head 18 can be brought in sliding contact for limiting the movement of the auxiliary shaft 16 in a first axial direction. The first abutment 19 can be a separate element mounted in the apparatus, such as a transverse beam member, or an element that is formed in a housing or frame 21 that is included in the apparatus.

In one embodiment, the tool 1 or 2 can itself provide a second abutment for limiting the movement of the auxiliary shaft 16 in an opposite second axial direction.

In one embodiment, as illustrated in FIGS. 1, 2 and 5, the second abutment is provided from an element 20 that is stationarily arranged in the apparatus, such as by mounting or by being formed in the housing or frame 21 that is comprised in the apparatus.

The first and second abutments 19, 20 are distanced by a horizontal gap 22 that permits the head 18 to move up and down in vertical direction between the abutments. To provide the entire auxiliary shaft 16 the same mobility, the auxiliary shaft passes a recess 23 formed in the second abutment 20. The recess 23 may be open in its upper end to facilitate insertion of the auxiliary shaft from above upon mounting.

Optionally, the first and second abutments 19, 20 may be combined and integrated in one singular physical component as shown in the embodiment of FIGS. 5a and 5b.

Another option foresees that the second abutment 20 and the link member 17 may be formed with equally inclined opposite surfaces that can be brought in mutual contact in a lifted end position of the tool, as illustrated by the tool 1 and the abutment 20 in the righthand set of tools in FIG. 1.

The auxiliary shaft 16 is this way restrained in the axial direction and mobile in transverse direction of the auxiliary shaft so as to follow the vertical displacement V of the tool as the tool is driven in reciprocating diagonal motion. The length of this vertical displacement V can be varied within the scope of the invention, and may advantageously amount to at least about 5 mm. In the same embodiment, the horizontal displacement H exerted by the tool on the auxiliary shaft 16 may amount to the range of 1.5-2 mm, for example, depending on the value of the angle α and the corresponding direction D of the reciprocating motion.

The treatment surfaces 3 and 4 may be supported in the proximal ends of holder members 24 respectively. The holders 24 are accommodated in holder cells 25 that are provided in a compartmentalized tool. The tools 1 and 2 thus form housings for a number of two or more holders 24, each of which carries a treatment surface 3 or 4, arranged side by side in row with adjacent treatment surfaces in the tool.

Each holder-accommodating cell 25 is defined at its upper end by a ceiling member 26. With reference to FIG. 2, the height h of the cell beneath the ceiling 26 is mated with the length l of the holder 24 such that the holder's vertical position in the cell is defined with no possibility for tipping or tilting, i.e., tipping forwards or backwards in the cell. In a corresponding way, see FIG. 3, the widths w1 of the cells 25 and w2 of the holders 24 are mated such that no substantial sideways tilting of the holders in the cells is allowed either. Still, when designing the cells and holders, dimensional tolerances must be considered to permit the holders to move substantially non-frictionally back and forth in the proximal direction P.

The holder 24 is provided a limited, spring powered, horizontal mobility within the cell 25 in order to allow for reciprocating movement back and forth in the proximal direction P (see FIG. 1). To this purpose, a spring member 27 inserted between the tool and the holder is effective for biasing the holder 24 and treatment surface 3 or 4 towards the opposite tool. The spring member 27 can be a coil pressure spring which is supported on a spring-holder pin 28 that protrudes from the holder towards a portion of the tool which defines a rear wall 29 in the cell 25.

More precisely, only each second cell 25 accommodates a holder 24 such that a proximal lower portion of the holder and the appurtenant treatment surface 3 or 4 can be received in an empty cell of the opposite tool in the most advanced spring-biased position of the holder. Accordingly, the treatment surfaces 3 and 4 will thus assume a crosswise overlapping relation. The treatment surfaces 3 and 4 will exert spring-biased contact with the sides of a knife as the same is inserted in a downwards movement into the V-shaped groove that is formed between the crosswise related treatment surfaces.

In order to ensure that an open entrance into the V-shaped groove is maintained also in the most proximally advanced holder positions of oppositely facing tools, a heel 30 may be arranged and protruding downwards from a lower end of the holder 24. This heel 30 is received to slide within a recess 31 that is formed in the bottom of the cell. The forward horizontal movement of the holder is halted as the heel 30 reaches the end of the recess 31, whereby the length of the recess is determined such that a minimum V can be at all times ensured for insertion of the knife upon initiation of an edge treatment operation.

Although not shown in drawings, corresponding combinations of heels and recesses may alternatively, or in addition, be arranged in the ceiling and in an upper end of the holder, or on the spring holder pin and in a side face of the cell, respectively.

The implementation of spring-biased treatment surfaces is beneficial in several ways. One advantage is that a perfectly horizontal orientation by the knife is not required, since the springs ensure an effective contact pressure from the treatment surfaces towards the cutting edge also if the knife is somewhat inclined during the treatment, i.e., if provided an upwardly or downwardly tipping knife-point.

Another advantage provided by spring-biased treatment surfaces is that the amount of metal removal can be controlled by regulating the depth of insertion of the knife between the treatment surfaces. This control is enhanced since the linearly reciprocating treatment surfaces provide for the removal of material and not a manually applied back- and forwards movement by the knife, as is the case in a non-driven, non-reciprocating tool arrangement. A lower position of the knife in the V-shaped groove thus results in higher contact pressure being exerted from the treatment surfaces and a resulting increased removal of material, as compared to an elevated position in the groove. However, in either case, the angle of the groove and the resulting cutting-edge angle is the same regardless of which height level in the V-shaped groove being applied during treatment.

The treatment surfaces 3 and 4 may be arranged on rod-shaped elements 32 that are journaled and provided a limited rotatable motion in the proximal ends of the holders 24. The rods 32 can be arranged rotatable about axes 33, which are oriented at the same inclination α vis-a-vis the vertical line VL as are the treatment surfaces 3 or 4 respectively. The rotational arrangement of the rods and the associated treatment surfaces provides the advantage of automatic adaptation to the orientation of a knife which is not moved in a continuous straight path between the treatment surfaces during operation.

In one embodiment the apparatus includes a rechargeable battery 34 to supply an electric motor 9. Battery charger and associated electronics may be integrated in the apparatus for charging the battery 34.

The solution presented here, in the form of treatment of cutting edges by rectilinearly reciprocating treatment surfaces, provides for economically efficient use of performing elements for grinding, polishing, honing, etc. Assuming, as an example, in a tool set comprising two opposite pairs of treatment surfaces, wherein the reciprocating motion includes a length displacement L of about 5 mm in treatment surfaces the width of 6 mm each, the total effective contact and wear on the treatment surfaces will be distributed over an area of 120 mm².

It shall be noted that the present apparatus for simultaneous treatment of both sides of a cutting edge is designed bearing in mind the possibility for modular extension of the arrangement. More precisely, the solution comprising individual connection of tools in succession onto a common drive shaft provides for insertion of additional tool sets on the drive shaft, all in successive order and alignment with each other. This modularity in structure allows for combinations of tool sets that are equipped for different treatments and/or for different edge angles. For example, a first tool set may be arranged for shaping the cutting edge into a narrow edge angle (secondary edge) whereas a second tool set may be arranged for shaping the cutting edge into a broader edge angle (primary edge/edge tip). In one tool set, the treatment surfaces may include diamond or other mineral or hard metal grains for grinding, whereas another tool set may be equipped with ceramic surfaces for treatment by honing or polishing. Another set up may include first and second tool sets equipped for shaping the cutting edge with primary and secondary edge angles, whereas a third tool set may be equipped for honing or polishing the primary edge. Still another set up may include three tool sets all of which provide different edge angles, such as 30°; 35°; 40°, or any other combination of angles in a faceted cutting edge, or which serves for restoring and treatment of cutting edges of different knife origin, such as Japanese or European style knives, e.g., in a multipurpose edge treatment apparatus.

From the above disclosure and drawings, skilled persons will appreciate the versatility, edge treatment efficiency and service life benefits provided by the invention, the scope and essence of which is defined by the appended claims.

While exemplary embodiments are described above, it is not intended that these embodiments describe all possible forms of the invention. Rather, the words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the invention. Additionally, the features of various implementing embodiments may be combined to form further embodiments of the invention.

Claims

1. An apparatus for the treatment of cutting edges comprising:

a first tool supporting a first set of treatment surfaces each having an axial length (L), in the apparatus oriented at crosswise relation to a second set of corresponding treatment surfaces supported in an oppositely arranged second tool, such that the treatment surfaces form in combination sides of a V-shaped groove with an opening angle determined by an intermediate angle between the first and second sets of treatment surfaces; wherein

connecting rods of the first and second tools are individually connected to a main shaft that is driven in rotation by a power unit, wherein one end of the connecting rod is pivotally connected to the associated tool and the opposite end of the connecting rod is pivotally connected to the main shaft via an eccentric that is rotationally journaled in the opposite end of the connecting rod, the eccentric being a cylindrical body through which the main shaft passes non-rotationally at an eccentric position between a centre and a periphery of the eccentric, such that in a set of first and second tools the appurtenant eccentrics are mutually rotated and angularly displaced on the main shaft, and wherein each tool and associated connecting rod are indirectly connected by an auxiliary shaft that runs in parallel with the main shaft, wherein the connecting rod is pivotally journaled on the auxiliary shaft and the tool is journaled on the auxiliary shaft for sliding movement in a length direction of the auxiliary shaft.

2. The apparatus of claim 1, wherein an angular displacement between the eccentric of the first tool and the eccentric of the second tool in a set of tools is in the range of 90°-270°.

3. The apparatus of claim 1, wherein the auxiliary shaft in one end carries a head that is movable in a gap formed between oppositely positioned abutments, one of which includes an upwardly open recess for passage of the auxiliary shaft, the abutments are configured to restrain the auxiliary shaft in axial directions while providing the auxiliary shaft mobility in transverse directions, transversely to the axial length of the auxiliary shaft.

4. The apparatus of claim 1, wherein the tools are in opposite sides journaled on linear guides arranged at inclinations that are parallel with the length directions of the associated sets of treatment surfaces.

5. The apparatus of claim 4, wherein the each of the guides includes a guide rod that is slidably received and axially movable inside a guide tube, wherein each tool includes a corresponding set of guide rod and guide tube arranged on opposite sides of the tool.

6. The apparatus of claim 1, wherein each tool has a set of at least two treatment surfaces arranged side by side in a row.

7. The apparatus of claim 1, further comprising two or more sets of first and second tools arranged in succession on a common main shaft, wherein one tool of each set of tools is lifted while another tool of each set of tools is lowered and vice versa, by rotation of the main shaft.

8. The apparatus of claim 1, further comprising an electrical power unit.

9. The apparatus of claim 8, further comprising a battery electrically connected to the power unit.

10. The apparatus of claim 2, wherein the angular displacement between the eccentric of the first tool and the eccentric of the second tool is 180°.

11. An apparatus for the treatment of cutting edges comprising:

a first tool including at least two first treatment surfaces;

a second tool, opposite the first tool, including at least two second treatment surfaces interleaved with the first treatment surfaces such the first and second treatment surfaces cooperate to define a V-shaped groove for receiving a cutting tool to be sharpened;

a main shaft supported for rotation;

first and second eccentric bodies rotationally fixed on the main shaft and longitudinally spaced from each other, wherein each of the eccentric bodies are associated with one of the tools, and the first and second eccentric bodies are angularly displaced relative to each other;

a first auxiliary shaft slidably connected to the first tool and arranged parallel to the main shaft at a location that is radially offset from the main shaft;

a second auxiliary shaft slidably connected to the second tool and arranged parallel to the main shaft at a location that is radially offset from the main shaft;

a first connecting rod having a first end connected to the first eccentric body and a second end connected to the first auxiliary shaft;

a second connecting rod having a first end connected to the second eccentric body and a second end connected to the second auxiliary shaft; and

a power unit configured to rotate the main shaft, wherein rotation of the main shaft causes the first and second tools to reciprocate up and down relative to the main shaft.