JPH02281902A - Edged tool for working woods - Google Patents

Abstract

PURPOSE:To eliminate the tendency for the rounding and dulling of a cutting edge even after the somewhat wear and keep its favorable sharpness by a method wherein wear resistant coating near the cutting edge is omitted over a plurality of positions on either one face of the cutting edge and wear resistant coating near the cutting edge is applied to the parts on the face opposite to the respective positions, at which said wear resistant coatings are omitted. CONSTITUTION:On cutting blade 4, coating 6 is applied both on the one face 4b and the other face 4c, which form cutting edge 4a. On both the faces, coating 4 near the cutting edge is omitted over a plurality of positions. At the same time, only on all parts on the side of the face opposite to the respective positions, to each of which coating 6 is omitted, coating 6 near the cutting edge is applied. Position, on the one face at which coating is omitted and or the opposite side face of which coating is applied, is continuously present over the whole range of the cutting edge. Thus, either face in contact with veneer develops self-polishing action, resulting in keeping comparatively favorable sharpness over the whole range of the cutting edge, even when the cutting edge wears to some degree.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a cutter for processing wood and materials of similar nature.

Conventionally, common cutting tools for processing wood have been made by brazing tool steel such as high-speed steel-alloy tool steel to the desired part of an alloy made of ordinary steel or the like, or by brazing the tool steel itself in the case of small-sized ones. It is a tool steel with a cutting edge formed as a dual-purpose alloy, and it is used in many fields because it can easily form a sharp cutting edge with appropriate toughness and is relatively inexpensive. The wear resistance of conventional blades is not very good, and in order to keep the sharpness of the cutting edge within practical limits, it must be re-sharpened or renewed quite frequently (small disposable blades, so-called replacement blades). Its short lifespan was a practical drawback.

Therefore, in recent years, attempts have been made to eliminate the drawbacks of conventional cutlery by applying a wear-resistant coating (hereinafter simply referred to as coating) made of hard chrome plating to the vicinity of the cutting edge of conventional cutlery. Although appropriate effects have been confirmed, it was discovered during the development process of the present invention that the known coating construction methods are not necessarily suitable for all types of cutlery, and that there is room for further improvement.

That is, first, in the example in which the entire cutting edge was coated,
The presence of the coating significantly reduces the progress of wear on the cutting edge, so the apparent lifespan is longer than that of conventional knives, but as it wears, the cutting edge gradually becomes rounded and dull, gradually losing its sharpness. This phenomenon still remains unresolved, and the problem is that the cutting edge is not sharp enough to require somewhat poor machining over a considerable period of time, from the middle to the final stage of use, and furthermore, the coating on the cutting edge When the blade is almost worn out, defects such as extreme loss of sharpness occur, and if the timing of re-polishing or renewal is incorrect, there are defects that can easily cause fatal machining defects, so generally, its practicality is low.

On the other hand, in an improved example in which a coating is applied to only one side forming the cutting edge or the other, the wear of the coated side is less than that of the uncoated side, and the coating is Since the so-called self-sharpening effect occurs, which preferentially wears out the remaining state, even if the cutting edge is slightly worn, there is no risk of it becoming rounded and dull as in the example above, and relatively good sharpness is maintained. Therefore, its practicality is high compared to the above example.

However, the sharpness of the cutting edge is maintained in a desirable state by the self-sharpening action.

limited to periods when the uncoated surface has relatively little wear;
As wear in the core progresses in the same way as with conventional cutters, the cutting edge becomes obtuse (a phenomenon in which the average cutting edge angle gradually increases), and the machining performance of the cutter as a whole gradually deteriorates. This is unavoidable and may eventually lead to machining defects, so even if the cutting edge does not become round and blunt, it will be necessary to re-sharpen or renew the cutting edge before the blunting of the cutting edge exceeds a certain limit.

Therefore, for example, in the case of a planer blade for a finishing planer that cuts very thin chips on the rake side, the load applied to one side of the surface that forms the cutting edge is relatively light, and therefore the wear on that one side surface is relatively light. Although it has the advantage of having a considerably longer lifespan than conventional cutlery if applied to specific uses where there is little, for example, various types of chestnut knives, veneer lace scoring cutlery, or ``veneer lace cutter devices.'' (Tokuko Showa 62-3088
Like many other blades, such as the replaceable blade similar to the blade disclosed in Publication No. 2), it is extremely unsuitable for use where a relatively large load is applied to both sides forming the cutting edge.

The present invention has been developed through repeated research to eliminate the above-mentioned unreasonableness, and can be applied not only to applications where the load on either side of the cutting edge is relatively light, but also to applications where the load on either side of the cutting edge is relatively light. It is particularly suitable for applications where a relatively large load is applied to the surface, and is an improvement to the blade that has a longer lifespan.
Specifically, coating is applied to both one surface and the other surface that form the cutting edge, and at least one of the surfaces is coated at least near the cutting edge at multiple locations. A unique configuration is adopted in which the coating is omitted and at least a portion of the opposite side of each location where the coating is omitted is coated near the cutting edge.

According to such a configuration, a self-polishing action will inevitably occur at multiple locations on the cutting edge where coating is omitted on one side and coating is applied on the opposite side, so that the cutting edge is Even if it is slightly abraded, there is no risk of it becoming rounded and dull as in the original fertilizer example, and relatively good sharpness is maintained, so it is excellent in practicality like the original fertilizer improvement example.

Moreover, even if a relatively large load is applied to a surface that has an uncoated area, there is always a coating next to the uncoated area, and the area is lower than the uncoated area by a step corresponding to the thickness of the area. It bears a lot of load and has a protective effect that prevents the wear of the uncoated parts from progressing in the same way as with conventional cutlery. As the step increases, there is a tendency to bear more load and increase the protective effect, so the obtuse angle of the cutting edge in the uncoated area is slow;
The risk of gradual deterioration of the machining performance of the blade as a whole is alleviated compared to the case where the cutting edge is improved, so re-sharpening or updating due to the obtuse angle of the cutting edge is less likely to occur over a long period of time compared to the case where the cutting edge is improved. This is effective because its lifespan is extended as a result.

Hereinafter, the present invention will be described in more detail with reference to an example of implementation illustrated in the drawings.

The embodiments illustrated in FIGS. 1 and 2 are "Veneer Cutting Apparatus" (Japanese Patent Publication No. 59-23241) and "Veneer Continuous Cutting Processing Apparatus" (Japanese Patent Publication No. 59-23241) filed by the present applicant.
This is an example in which the blade according to the present invention is applied to a veneer cutting device disclosed in Japanese Patent Publication No. 23527).

That is, the cutting device can cut the outer peripheral portions 1a and 2a as necessary.
A pair of transport rolls 2 are each covered with a friction reinforcing member made of rubber, synthetic resin, etc. and also serves as a cutting blade protection member, and are arranged opposite each other to be driven in the direction of the arrow shown in the figure via a drive source (not shown).
and a replaceable cutting blade 4 whose cutting edge faces in the opposite direction to the conveying direction of the veneer 5 and which is held replaceable at any time via a knife holder 3. (not shown), the cutting blade 4 is alternately reciprocated via the knife holder 3 to the position shown by the dotted line and the position shown in actual combat (if necessary, the limit position is regulated by a stopper not shown). By moving the veneer, the shoulder portion 5a of the veneer can be removed.
It is configured to be able to perform regular length cutting for each predetermined size.

The cutting blade 4 is coated with a coating 6 on both one surface 4b and the other surface 4C forming the cutting edge 4a. A form in which the coating 6 near the cutting edge is omitted, and the coating 6 is applied to the vicinity of the cutting edge only in all areas on the opposite side of each location where the coating 6 is omitted (see Fig. 2). Become.

For example, in a cutting device configured as described above, a large load is applied to both sides of the cutting edge of the cutting blade each time a veneer is cut. Deterioration of cutting ability due to obtuse angle etc. is relatively fast,
There was a high risk that the veneer could not be completely cut, and problems such as buckling of the veneer between the approach position of each transport roll and the cutting edge position of the cutting blade would frequently occur at an early stage.

However, in the cutting blade of the above embodiment, the coating is omitted on one side and the coating is applied on the opposite side, which continuously exists over the entire area of the cutting edge. Since a self-sharpening action occurs at any part of the blade that comes into contact with the veneer, even if the cutting edge is slightly worn, relatively good sharpness is maintained over the entire area of the cutting edge. Even in cases where there is no coating, there is always a coating next to the uncoated area, and it has a protective effect that prevents the wear of the uncoated area from progressing in the same way as with conventional cutlery. Since the cutting edge becomes obtuse at certain points, the deterioration of the cutting ability is relatively slow, and the risk of the above-mentioned problems occurring early and frequently is eliminated, resulting in a longer service life.

The embodiment illustrated in FIG.
This is an example in which the cutter according to the present invention is applied to a veneer lace scoring device disclosed in Publication No. 3).

That is, the scoring device is a re-sharpening type veneer cutting blade 11.
A double-edged coarse-cutting tool 7 and a single-edged finishing tool are supported via a tool holder 9 so that they can be replaced at any time, and are attached to the cutting edge of the veneer lace that cuts the veneer 5 from the raw wood 10. It is equipped with a pulling knife 8, and is provided with a rough cutting knife 7 in advance,
The ruled layer 5b of an unspecified width is divided from the end of the raw wood 10, and then the ruled layer 5C of a certain narrow width is divided from the inside edge using a finishing creasing knife 8. The structure is such that the cutting resistance of 5C is reduced and stabilized, and the end surface of the veneer 5 can be improved.

In both the rough cutting and finishing scoring knives, as in the above embodiment, both one surface and the other surface forming the cutting edge of each scoring knife are coated. , on any surface, coating near the cutting edge was omitted at multiple locations, and the coating near the cutting edge was limited to all localities on the opposite side of each location where coating was omitted. Consists of a coated form.

For example, in a scoring device configured as described above, since the load is much larger in the cutting direction, wear is likely to become apparent, and when the cutting ability of each scoring tool deteriorates, the cutting edge of the veneer Inconveniences such as roughening of the surface and damage to small-diameter logs occur, so it was necessary to update the conventional cutlery and the cutlery of the pioneer improvement example at an early stage. In the case of pulled knives, by omitting and applying coating at multiple locations over the entire area of the cutting edge as described above, a self-sharpening effect occurs at any part that comes into contact with the raw wood, resulting in good sharpness. In addition to this, the obtuse angle of the cutting edge in the uncoated area is reduced, and the deterioration of the one-cutting ability is alleviated, so there is no need to update it as early as possible, which is effective.

In addition, as in both of the above embodiments, on any surface forming the cutting edge, only the entire local area on the opposite side of each location where the coating was omitted, in other words, each location where the coating was omitted. In contrast, if a coating is applied, it is most effective in maintaining the sharpness of the cutting edge because it has the ability to generate a self-sharpening action over the entire area of the cutting edge. However, it is not limited to this form, and various changes may be made as described below.

That is, FIG. 4 shows that in the double-edged ruled cutter shown in the example of FIG. This is an example of a modification in which coating is applied to a part of the opposite side of each coated location with an arbitrary width. According to this construction form, the cutting edge of multiple locations where coating is present on both sides. There is a risk that the sharpness of the cutting edge may be impaired in some parts, but since these parts are dispersed in multiple locations, and all other parts of the cutting edge have a function that can cause self-sharpening action, the overall sharpness may be impaired. Sexual loss is minor;
Considering the advantage that overall wear is reduced by increasing the width of the coating compared to both of the embodiments described above, this is particularly suitable when the loads on both sides are considerably large.

On the other hand, FIG. 5 shows that in the double-edged ruled cutter shown in FIG. This is an example of a modification in which a coating is applied. According to such a construction form, the sharpness of the cutting edge is likely to be impaired in multiple parts of the cutting edge where coating is omitted on both sides. I'm here.

In addition, since all other cutting edge parts have a function that can generate self-sharpening action, the overall loss of sharpness is slight, and both sides can be applied to applications with relatively heavy loads without any particular problem in practical use. .

Furthermore, Fig. 6 shows a modified example of the single-edged lined cutter shown in Fig. 3, in which the coating is omitted in multiple places only on the back of the blade, and the entire surface of the blade is coated. According to this type of construction, there is a risk that the sharpness of the cutting edge may be impaired at multiple locations where the coating is present on both sides, but these sections are dispersed in multiple locations, and other Since all the cutting edge parts have a function that can generate self-sharpening action, the overall loss of sharpness is slight, and since the entire blade is coated on one side, there is an advantage that wear is extremely reduced. This is particularly suitable when the load on one side is quite large.

As is clear from the above-mentioned modifications, the method of applying the coating is to omit coating in the vicinity of the cutting edge at multiple locations on at least one of the surfaces forming the cutting edge, and to remove the coating. At least a portion of the side opposite to each omitted location may be coated near the cutting edge, and the omitted shape of the coating may be one other than the thin strip shape as shown on each side, for example, as shown in Fig. 7. Any shape may be used, such as a semicircular shape as exemplified in , or a triangular meeting shape or a semi-elliptical shape (though not shown), and the coating can be omitted in any shape by conventionally known masking means. .

However, if the width of each location where the coating is omitted is excessively wide, the abrasion protection effect of the coating will be difficult to spread, so it is better to omit the coating at many narrow locations than to omit the coating from a small number of wide locations. This was advantageous, but on the other hand, there were also advantages and disadvantages in manufacturing, such as the more parts the coating was omitted, the more complicated the masking means, etc. Also, considering the difference in the fiber direction of the veneer and raw wood with respect to the processing direction, The example in Figure 1 and Figure 2 is
Compared to the example shown in the figure, there are characteristics in which the range of the wear protection effect increases or decreases depending on the relationship between the internal structure of the wood and the processing direction, such as the wear protection effect of the coating spreading more easily, so the specific width is as follows: It is preferable to verify and select items in accordance with the actual situation, taking these matters into account.

In addition, the base material and coating material of the blade can be any conventionally known material, and the thickness of the coating can be a few JLm or less.
If necessary, there is no problem even if it is north of 10gm.
Alternatively, there is no problem in adopting a construction method in which multiple types of coatings with different hardness, toughness, etc. are applied to different parts individually or overlappingly to the same part, and furthermore, it is also possible to simply finish polishing the coating. It was effective.

I would also like to add that the blade according to the present invention described above has a property that the microscopic straightness of the cutting edge collapses when the cutting edge recedes slightly due to wear, but within the extended life span, the blade collapses. Because the absolute amount of straightness is extremely small and the overall sharpness is not easily impaired, there is no risk that the processed surface of the wood will become uneven or rough beyond practical limits. , was confirmed through many uses including uses other than the above-mentioned examples.

[Brief explanation of drawings]

The drawings are for explaining the present invention, and FIG. 1 is an explanatory side view of a veneer cutting device to which the cutter according to the present invention is applied, and FIG. 2 is a diagram showing the cutting edge of the cutter used in the device shown in FIG. FIG. 3 is a side view of a veneer lace marking device to which the cutter according to the present invention is applied; FIG. FIG. 6 is a perspective view of another embodiment of the cutter used in the apparatus shown in FIG. 3, and FIG. 7 is a partially enlarged plan view of the cutting edge of the cutter. ■, 2... Conveyance roll, 3・φ・Knife holder, 4
... Cutting blade, 5, φ, veneer, 6... Covering, 7...
Rough cutting cutlery, 8... Finishing cutter, 9 fist... Knife holder, lO... ψ log, 11... Fist veneer cutting knife Patent applicant Meinan Seisakusho Co., Ltd.

Claims (1)

[Claims] A cutting tool for processing wood, in which one surface forming a cutting edge and the other surface are coated with a wear-resistant coating, and at least one of the surfaces is coated at multiple locations. In addition to omitting the wear-resistant coating near the cutting edge,
A cutter for processing wood, characterized in that a wear-resistant coating is applied to the vicinity of the cutting edge on at least a part of the opposite side of each location where the wear-resistant coating is omitted.