DE2121985A1 - Method and device for grinding tool cutting edges - Google Patents

Description

TEMPOOL PTY. LIMITED ,. 26-30 Gilby Road, Netting Hill, (State Victoria) / Commonwealth of Australia

'' Method and device for grinding tools

cut"

The invention relates to a method and devices for grinding small hand tools such as chisels for carpenters and flat blades or Cutting, however, is not based on these specific examples limited by tools, as appropriately trained cutting edges in many branches of industry and in used in many professions.

Conventional grinding processes of this general type, which normally consist of a strip of steel up to 75 mm wide and about 12 mm thick, consist of that first a bevel is ground on one side of the cutting edge and then a honing of Hand of the beveled bevel of the cutting edge is done on a fine oil stone, in order to result from grinding Remove burrs. Normally, the Loops formed bevel or bevel a ge ■ * Slightly smaller angle than that created during honing. The cutting edges can therefore in the normal case several

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The fee schedule of the German Chamber of Patent Attorneys applies to the contract. · Place of jurisdiction (original performance and payment: Nuremberg. Telephone calls have no legally binding effect.

Times to be honed before renewing the bevel or bevel is required. The steps involved in forming a satisfactory edge • be carried out in the conventional way considerable skill or experience in making the required angle parallel to the whole surface to adhere to the tool; when the operator

If it is not extraordinarily skillful, it becomes a very fuzzy one
different y edge received. .

There is another disadvantage of the conventional method in that the final high creates a fine burr which must be removed by, that the edge is ground off from the back of the cutting edge. This grinding sets the sharpness of the r Cut down. If the burr created by honing is not removed, it has a tendency to become ^ during of cutting. This means an effective increase in the edge or cutting edge thickness of the tool up to twice its original thickness, which significantly reduces the sharpness.

A tool grinding machine is already known (U.S. Patent 1,963,394), which includes a pair of grinding wheels and has a lapping disc which are arranged coaxially with one another, and which furthermore have a Has tool carrier that holds a tool to be sharpened at a constant angle to the grinding wheels and the Lappseheibe is able to hold, but the carrier from one movable table to another TÜSch must be moved to use the lapping disc.

A tool grinding machine is also known, (U.S. Patent 3,019,562), which includes a pair of coaxial grinding wheels that are attached to a workpiece in Contact can be brought, and the one each have different diameters, so that a fine

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and rough grinding by moving the disks across to the work piece can be carried out without the distance of the axis of the disks from that; Workpiece is changed.

The invention is based on the object of a method for the purpose of the tool cutters mentioned at the beginning Specify the genus so that a clean, sharp edge on the cutting edge is reproducibly produced without that some skill is required and taking the time required compared to the conventional one Process is reduced, as well as to provide devices for performing this process.

According to the invention, this object is achieved in that the bevel of the front side of the cutting edge is first included a grinding wheel is brought into contact at a predetermined fixed angle and then with a honing wheel under a slightly

larger angle, so that the burr created during grinding is removed.

According to the invention, the tool is advantageously clamped on a slide which is perpendicular to the two Disks is movable, of which the grinding wheel has a larger diameter and wherein the shafts of the Slices based on the carriage are set so that the required angle difference is maintained automatically when the slide and the one attached to it Blade or cutting edge from the grinding wheel to the honing wheel is moved.

According to the invention, the honing grinding wheel can be a wheel made of flexible material, onto which a wax-based powder or some other carrier-based powder is applied for lapping ^{; :} brought-lsi ;. A device according to the invention for carrying out the method according to the invention has' ■ "'-" abrasive -lind an abrasive abrasive ·,'^; einii- "drive

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BATH ORIGINAL

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for the abrasive and the honing abrasive, a tool carrier that extends across the abrasive and honing abrasive means is movable on, the honing abrasive means from the tool carrier in a greater distance than the grinding means, so that one of the tool slide or carrier or Support held cutting edge at a greater angle 'to the honing abrasive than to the abrasive.

Advantageously, an inventive Grinding machine a grinding wheel and a honing wheel on, the wheels spaced from each other and are arranged coaxially, as well as drive means for the disks, a tool carrier, for receiving and clamping a blade or cutting edge along an axis parallel to the axes of the disks is movable, the diameter of the grinding wheel being larger than that of the honing wheel, so that a blade or cutting edge carried by the tool carriage at a greater angle to the honing wheel pending than to the grinding wheel.

Further features and advantages of the invention as well as that according to the invention Methods are explained on the basis of an exemplary embodiment Device according to the invention explained in more detail in the drawing. It shows:

1 shows a perspective view of a device or grinding machine according to the invention;

Pig. 2 shows a plan view of a grinding machine according to the invention and,

3 shows a section along the line 3-3 according to FIG. 2. _3, the arrangement of the grinding wheels being shown in dashed lines.

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A device according to the invention has a housing 1 on, in which a motor 2 with a shaft 3 * 3 is arranged which protrudes to both sides of the motor, with a grinding wheel 4 on the shaft section 3 on one side of the motor and a honing wheel 5 * on shaft section J ^ on the other Side of the engine is arranged or fitted.

The grinding wheel is a conventional grinding wheel of a grade suitable for the hardness of the to grinding cutting; the honing wheel is made of a flexible material such as a material sold under the trademark "Corfam" or equivalent other synthetic materials.

The honing wheel has from those discussed below Establish a smaller diameter than the grinding wheel.

On the housing 1 or an additional subframe attached to it is a rail 6, the axis of which is parallel to the axis of the motor shaft _3, 3'1St 3, where a displaceable support 7 is arranged on this rail. As can be seen from the drawing, the support 7 is designed as a clamp with a lower part 8 which has an eyelet 9 which forms a tightly sliding fit around the rail 6 and with a lower clamping jaw 10. On the clamping jaw 10 is a " upper jaw 11, whereby the connection is effected by screws: 12, which are guided through smooth openings in the upper clamping jaw and correspondingly drilled openings in the lower clamping jaw. The length of the screws is sufficient so that the thickest cutting edge 13, for the a grinding machine according to the invention is used, can be arranged between the clamping jaws 10 and 11. If necessary, can

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a locking screw Ik can be provided in the upper clamping jaw 11 so that the blade or cutting edge 15 is fixed. Furthermore, a guide can be provided on the lower clamping jaw against which the blade or cutting edge abuts, so that it is ensured that the blade -bzv ?. Serneide is at a right angle to the rail C. _ ■ _

As can be seen from the drawing, the upper surface 15 of the housing several ■ index marks Io on, against which the beveled edge of a blade 13 are applied can to ensure that the angle at which the Bevel is to be ground, corresponds to the predetermined angle and, if necessary, to ensure that the edge of the blade 13 is arranged parallel to the axes 3.3 of the disks 4.5. Farther

can, depending on requirements, on the housing or the Slide an adjustable support can be arranged, which supports the blade in the vicinity of its contact point with the disk supported to the amount of too to limit the material to be removed and also to promote compliance with the actual angle. According to the invention such a support can be arranged adjacent to the grinding wheel. It can also be an edition be arranged, which can be moved along the grinding wheel, there can also be two such supports be arranged, of which one; e is assigned to the grinding wheel and the other is assigned to the Abziehschlesifscheibe is. ;

When processing the blade is on the support means of the screws 12 tensioned, the length by which the blade should protrude by the setting of the Edge of the blade set on an index mark: £ ung 16 and then the screw 14 is tightened. Of the The motor is then switched on, e.g. by a switch 17.

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tet, the tool forward and backward over the Grinding wheel 4 moves until a ground surface is formed at your desired angle. In this Point in time, the support 7 is moved on the rail 6, See the edge of the tool above the honing wheel 5 is located. Since the honing wheel has a smaller diameter than the grinding wheel, in reality only the tip of the edge occurs with the honing grinding wheel in contact, wherein the Lr'ppulver in a carrier substance, the grinding wheel from the is carried, acts on this surface and the outermost edge of the tool is very precise and polished very smooth.

It has now been found that the one resulting from the grinding Burr is removed and that the honing wheel does not have any Ridge causes. There is therefore the surprising result that the back of the blade does not must be honed or treated in any other way. As a result, the cutting edge is not stepped or discontinued.

It has been found that any surface irregularities are normally less than about 1.01 mm (Ο, θ4θ inch) and that the surface accuracy is of the order of 0.1 / rev.

Microscopic examination of the cutting edge at up to 10.QOO times magnification showed that he is according to the invention The method produces a cutting edge free of any burrs that is thicker than about 0.0002 mm (0.00001 inch).

It can be seen that the ground edge is extreme is sharp and can be expected to cleanly cut difficult to machine materials and that it for longer operating times than was previously possible,

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BAD ORIGINAt

can be used.

Instead of the disks, according to the invention, zv / ei Step endless belts, one of which is coated with an abrasive and the other with a tel for lapping contains or can accommodate a compound for lapping. When using belts, the Belt for lapping be further removed from the support than the belt for grinding, in order to achieve the invention Ensure assignment.

- Expectations -

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Claims (6)

Expectations fl)) Method for grinding ', / tool cutting, characterized in that the cutting edge is arranged on a support that the support is moved in such a way that '' the cutting edge or blade in contact with an abrasive occurs to form an inclined edge or to form again, that the support is still moved so that the cutting edge comes into contact with a honing abrasive in a plane parallel to the plane of the Abrasive, but at a greater distance from the backing, with the cutting edge on the abrasive is peeled off so that grinding burrs are removed from the inclined surface with the formation of a sharp cutting edge will. 2.) Grinding machine for sharpening tool edges, in particular for carrying out the method according to claim 1, characterized by an abrasive and a stripping abrasive, by a drive for the abrasive and for the stripping abrasive, by a movable tool carrier transversely to the abrasive and the stripping abrasive wherein the honing abrasive is further away from the tool holder than the abrasive, so that a blade or cutting edge carried by the toolholder is at a greater angle to the honing abrasive than to the abrasive. 3.) Grinding machine for sharpening tool edges, in particular for performing the method according to claim 1, characterized by a grinding wheel and an honing wheel, the disks being spaced apart and arranged coaxially, by means of drive for the disks, by a tool carrier for receiving and for holding on a blade or cutting edge, which can be moved along an axis parallel to the axes of the disks, the diameter of the key -2- 109848/1293 wheel is larger than that of the honing wheel, so that a blade carried by the tool carriage is at a greater angle to the honing wheel than to the grinding wheel. 4.) Apparatus according to claim 3 j characterized in that both disks are arranged on a shaft of the motor, wherein the one disk is on one side and the other disk on the other side of the motor. 5 ·) Device according to claim 3 *, characterized in that the tool slide is arranged on a rail parallel to the disk axes, that the rail is connected to the grinding machine housing to which the disks are also connected. 6.) Device according to claim 3 j, characterized in that the housing has at least one index mark parallel to the axes of the discs, the index mark is arranged such that when a blade or cutting edge arranged on the tool carrier touches the marking, a given angle for the bevel is ground. 7 ·) Device for carrying out the method according to claim 1, characterized by a grinding belt and an Aqschieifriemen, wherein the belts are arranged in the grinding position in parallel planes, by means of drive, for the belt, by a tool carrier for receiving and tensioning a: blade or Cutting edge which is movable parallel to an axis transverse to the belt, the arrangement being such that a blade held by the tool carriage is at a greater angle to the honing abrasive belt than to the abrasive belt. 109848/1293