JPS60245726A - Rotary blade for agricultural machinery - Google Patents

Abstract

PURPOSE:To improve cutting quality and wear resistance and to improve toughness and rigidity as well by constituting an edge part and a part corresponding to the rear thereof of a reheat-treated zone having extremely high hardness and the intermediate part of a reheat-treated zone having fine structure and forming the reheat-treated zone into a parallel band shape. CONSTITUTION:The heat-treated zone of the fine pearlite structure having 40-45 hardness HR is formed to the intermediate of the edge part and the rear part thereof of the rotary blade for agricultural machinery constituted by forming the edge part to one side of a slice body provided with a mounting hole for mounting to a revolving shaft. The reheat-treated zones of the martensite structure having 50-65 hardness HR are respectively formed to the parallel band regions enclosing respectively the edge part and the rear part thereof. The reheat-treated zone of the martensite structure having 50-65 hardness HR is preferably formed further between the mounting hole and the heat-treated zone of the fine pearlite structure.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rotary blade for agricultural machinery used in grass mowers, lawn mowers, and the like.

Rotary blades used in grass mowers, lawn mowers, etc. are usually
As shown in FIGS. 14 to 17, a piece in which a blade part (1) is formed on one or both sides of a piece-shaped body provided with a mounting hole (6) for mounting on a rotating shaft, in other words, A blade part (1) is formed on one side of the flaky body, and the other side is the back part 2.
) (see Figures 14 or 16), or blades (1) are formed on both sides of the strip (see Figures 15 or 17). ing.

Such conventional rotary blades for agricultural machinery are made of SK material (carbon tool steel).
Alternatively, after forming a material made of SKS material (alloy tool steel) into a predetermined shape, that is, a flaky shape having a mounting hole (6), a blade part (1) is formed by grinding with a grinder or the like. ) was generally manufactured by subjecting it to local quenching and tempering treatment. When we observed the metal structure of such a conventional rotary blade, we found that the blade part (1) was HRC55.
It consisted of a martensite structure with a hardness of H to 58, and the portion other than the blade part (1) consisted of a pearlite structure with a hardness of H and an IC of 20 to 32.

However, in the conventional rotary blades as described above, due to the emphasis on sharpness and wear resistance, insufficient consideration was given to the metal structure of parts other than the blade part (1), so the overall performance of the rotary blade was It was not sufficient in terms of toughness, rigidity, etc.

Therefore, when agricultural equipment incorporating such a rotary blade is used, when the rotary blade comes into contact with an obstacle such as a stone, the rotary blade is damaged and its fragments are scattered, causing unexpected personal injury. There was a problem. There is also the problem that the rotary blade is bent and cannot withstand subsequent use.

In contrast, the present inventors formed a reheat treatment zone made of a fine pearlite structure in the middle part of the rotary blade, and reheated a reheat treatment zone made of a martensitic structure in an arcuate region including the blade part or back part of the side edge. He developed a band-forming device and provided a tentative solution to the above problem (Special Publication No. 43201/1983).
.

However, even the rotary blade described above has room for further improvement. For example, when considering the rotary blade from the viewpoint of its service life, it is not preferable that the reheat treatment zone made of martensitic structure is formed in an arc shape. This is because when a certain degree of wear or damage occurs on the cutting edge of a rotating blade, it is common practice to re-grind the cutting edge to improve the useful life of the rotating blade. This is because when the reheat treatment zone made of martensitic structure is formed in an arc shape, when the cutting edge is reworked, a portion with low hardness is likely to be exposed, so that reworking of the rotary blade tends to be ineffective.

The present invention was made against this background, and its purpose is to provide not only excellent sharpness and wear resistance, but also excellent toughness, rigidity, etc., and to improve the cutting edge. It is an object of the present invention to provide a rotary blade for agricultural machinery which is preferable even when it is possible to improve its service life by modification.

In the rotary blade for agricultural machinery according to the present invention, in order to improve sharpness and wear resistance, the blade portion or a portion corresponding to the back portion thereof is configured with an extremely hard reheat treatment zone, and in order to improve toughness and rigidity. The intermediate part (between the blade parts or between the blade parts and the back part) is composed of a reheat treatment zone with a fine structure, and the reheat treatment zone is parallel to the reheat treatment zone in order to improve the service life by refinishing the cutting edge. It is made into a band shape.

That is, in the rotary blade for agricultural machinery according to the present invention, the rotary blade for agricultural machinery has a blade portion formed on one side of a piece-like body provided with a mounting hole for mounting on a rotating shaft. A heat-treated zone with a fine pearlite structure having a hardness of H, C40 to 45 is formed between the blade part and the back part, and a hardness of H, C50 to
It is characterized in that reheat treatment zones of a martensitic structure of 65% are formed respectively. In addition, in rotary blades for agricultural machinery in which blade parts are formed on both sides of a piece-shaped body provided with a mounting hole for mounting on a rotating shaft, a fine grain with a hardness of HRC 40 to 45 is provided between the two blade parts. It is characterized in that a heat treatment zone of pearlite structure is formed, and a reheat treatment zone of martensitic structure having a hardness of HRC 50 to 65 is formed in each of the parallel band regions respectively including the above-mentioned double edge parts. There is. Furthermore, in the case of a rotary blade for agricultural machinery in which blade portions are formed on three sides of a piece-shaped body provided with a mounting hole for mounting on a rotating shaft, and on both sides and the end surface, the rotary blade is surrounded by the blade portions formed on the three sides. A heat-treated zone with a fine pearlite structure having a hardness of H, C40 to 45 is formed in the cut portion, and a U-shaped band region that includes the entire blade part has a hardness of HRC50 to 45.
It is characterized in that it forms a reheat treatment zone with a martensitic structure of No. 65.

Hereinafter, the present invention will be explained in the drawings (Figs. 1 to 12) showing the embodiments thereof.
This will be explained in detail based on Figure).

Figures 1 and 2 (both plan views) show the mounting hole (6).
1 shows an embodiment of the present invention in a rotary blade for agricultural machinery in which a blade portion (1) is formed on one side of a piece-like body provided with a blade. In this embodiment, a heat treatment zone (A) of a fine pearlite structure having a hardness of HRC40 to 45 is formed between the blade part (1) and its back part (2), and the heat treatment zone (A) is formed between the blade part (1) and its back part (2). A reheat treatment zone (B) of a martensitic structure with a hardness of H and C50 to 65 (shaded area in the figure) is included in the parallel band-shaped body region (parallel to the cutting edge of the rotary blade) that includes the back part (2) and the back part (2), respectively. ) are formed respectively. Such a rotary blade is made of SK material or a material made of SKS material and has a mounting hole (6).
After forming a blade portion (1) by forming a flaky body having a shape and performing grinding or the like on the flaky body,
A portion corresponding to the above-mentioned heat treatment zone (A) is formed by subjecting the entire strip-like body to quenching and tempering treatment, and then, by subjecting the parallel strip-like body region to local quenching and tempering treatment, the above-mentioned It is obtained by forming a portion corresponding to the reheat treatment zone (B).

This rotary blade has a blade part (1) and its back part (2) composed of a reheat treatment zone (B) with extremely high hardness, so it has excellent sharpness and wear resistance. Blade part (1
) and its back part (2) is composed of a heat-treated zone <A) with a fine structure, which is excellent in terms of toughness and rigidity. Since it is formed into a parallel band shape instead of a straight blade, it is preferable for modifying the cutting edge and improving the life of the rotary blade.

Fig. 3 shows that the blade part (1) is also formed on the back side of the back part (2) of the piece-like body shown in Fig. 2, and it is clogged.
This figure shows the state in which the present invention is applied to a rotary blade for agricultural machinery in which blade portions (1) are formed on both sides of a flake. In this case as well, the effects of the present invention described above can be obtained by forming the heat treatment zone (A) and the reheat treatment zone (B) similar to the case of FIG.

Figures 4 to 6 (all plan views) show a martensitic structure with a hardness of HRC 50 to 65 between the mounting hole (6) and the heat treatment zone (A) for the above-mentioned rotary blade. Reheat treatment zone (C) (corresponds to the shaded area in the center of the figure)
The figure shows a further formed version of . In order to obtain such a rotary blade, when performing local quenching and tempering treatment to form the reheat treatment zone (B), at the same time, the reheat treatment zone (C) is
What is necessary is to form .

Such a rotary blade has greater rigidity as a whole than the rotary blade described in FIGS. 1 to 3.

Figures 7 and 8 (both plan views) show the mounting hole (6).
1 shows an embodiment of the present invention in a rotary blade for agricultural machinery in which blade portions (1) are formed on both sides of a piece-like body provided with a blade.゛In this embodiment, a heat-treated zone (A) of a fine pearlite structure having a hardness of HRC40 to 45 is formed in the middle of the double-edged portion (1), and parallel belt-shaped regions (A) each encompassing the double-edged portion (1) are A reheat treatment zone (B) (corresponding to the shaded area in the figure) of a martensitic structure having a hardness of HRC 50 to 65 is formed in the band-shaped area parallel to the cutting edge of the rotary blade. In such a rotary blade, a piece-like body having a mounting hole (6) is formed from a material made of SK material or SKS material, and a blade portion (1) is formed by grinding the piece-like body with a grinder or the like. After that, the entire flake is subjected to quenching and tempering treatment to form a portion corresponding to the heat treatment zone (A), and thereafter, the parallel strip area is locally quenched and tempered. It is obtained by forming a portion corresponding to the reheat treatment zone (B).

This rotary blade has a double-edged part (1) composed of a reheated zone (B) with extremely high hardness, so it has excellent sharpness and wear resistance. Since it is composed of a heat treatment zone (A) with a fine structure, it is excellent in terms of toughness and rigidity, and furthermore, it has a reheat treatment zone (B).
Since it is formed into a parallel band shape rather than an arc shape, it is preferable for modifying the cutting edge and improving the life of the rotary blade.

Figures 9 and 10 (both plan views) show a martensitic structure with a hardness of H, C50 to 65 between the mounting hole (6) and the heat treatment zone (A) for the above-mentioned rotary blade. A reheat treatment zone (C) (corresponding to the hatched area in the center of the figure) is further formed. In order to obtain such a rotary blade, when performing local quenching and tempering treatment to form the reheat treatment zone (B), a reheat treatment zone (C) may be formed at the same time.

Such a rotary blade has greater rigidity as a whole than the rotary blade described in FIGS. 7 and 8.

FIG. 11 (plan view) shows an embodiment of the present invention in a rotary blade for agricultural machinery, in which blade portions (11) are formed on three sides of a piece-like body provided with mounting holes (6) and on three sides, including the end face. It is something. In this rotary blade, a heat treatment zone (A+) is formed in a portion surrounded by the blade portion (11), and then
It is preferable to form a U-shaped reheat treatment zone (B,) which includes all of the blade portions (11), corresponding to the above-mentioned parallel belt-shaped reheat treatment zone (B).

FIG. 12 (plan view) shows that the hardness is HRC50 between the mounting hole (6) and the heat treatment zone (A1) for the above-mentioned rotary blade.
Reheat treatment zone (C) of martensitic structure with ~65
(corresponding to the hatched area in the center of the figure) is further formed. In order to obtain a rotary blade that bends, a reheat treatment zone (C) may be formed at the same time as the local quenching and tempering treatment is performed to form the reheat treatment zone (B1).

Such a rotary blade has greater rigidity as a whole than the rotary blade described in FIG. 11.

FIG. 13 shows a more preferable example of the rotary blade according to the present invention, in which a rotary blade in which a double-edged part (1) of a piece-like body is formed (see FIG. 8).
is shown as an example. When using a rotary blade for agricultural machinery, there is a possibility that obstacles such as stones may come into contact with parts other than the blade or its back.

In order to cope with such a situation, a reheat treatment zone (B2) that also serves as a reheat treatment zone (portion (B) in Fig. 8) that includes the blade part (1) is provided around the entire circumference of the rotary blade. It was formed. Note that a reheat treatment zone (B3) is also formed around the mounting hole (6) in order to improve its wear resistance. Such a rotary blade can further enhance the effect of the rotary blade according to the present invention.

In addition, in the above description, only the planar shape of the reheat treatment zone was mentioned, but it is preferable that an unhardened soft layer exists inside the reheat treatment zone. This is to give toughness and stickiness to the rotating blade.

As detailed above, the rotary blade for agricultural machinery according to the present invention has the blade portion or the portion corresponding to the back portion thereof constituted by a reheat treatment zone with extremely high hardness, and the intermediate portion between the blade portions and the portion corresponding to the back portion of the blade portion. The middle part between the back part or the part surrounded by the three blade parts is made up of a heat-treated zone with a fine structure, and the reheat-treated zone is in the form of a belt parallel to the blade part, which improves sharpness and wear resistance. It can be said that it is a rotary blade that is not only excellent in terms of this, but also in terms of toughness, rigidity, etc., and is also convenient for modifying the cutting edge and improving its useful life.

As described above, the present invention is extremely excellent in improving the quality, life, safety, etc. of rotary blades for agricultural machinery.

[Brief explanation of drawings]

1 to 12 are plan views showing embodiments of the present invention.
FIG. 3 is a plan view showing a more preferable example of the rotary blade according to the present invention, and FIGS. 14 to 17 are plan views showing conventional rotary blades for agricultural machinery. 1: Blade portion, 2: Back portion, 6: Mounting hole, A, A,: Heat treatment zone, E3. E3. , C: reheat treatment zone. Agent Patent Attorney Arata Miyazaki Department 4 Figure 9 Figure 10 Figure 12 Figure 14

Claims (1)

[Scope of Claims] +11 A rotary blade for agricultural machinery in which a blade part is formed on one side of a piece-like body provided with a mounting hole for mounting on a rotating shaft, in which a blade having a hardness is formed between the blade part and its back part. is H+tC40
A heat treatment zone of a fine pearlite structure having a hardness of HRC 50 to 45 is formed, and a reheat treatment zone of a martensitic structure having a hardness of HRC 50 to 65 is formed in each of the parallel band regions respectively encompassing the blade portion and its back. A rotary blade for agricultural machinery characterized by: (2) In a rotary blade for agricultural machinery in which a blade is formed on one side of a piece-shaped body with a mounting hole for mounting on a rotating shaft, there is a blade with a hardness of H* between the blade and its back. C40
A heat treatment zone of a fine pearlite structure having a hardness of Hn C50 to 45 is formed, and a reheat treatment zone of a martensitic structure having a hardness of Hn C50 to 65 is formed in each of the parallel band regions respectively encompassing the blade part and its back part. , furthermore, between the mounting hole and the heat treatment zone of the fine pearlite structure, the hardness is HR0.
1. A rotary blade for agricultural machinery, characterized in that a reheat treatment zone is formed with a martensitic structure having a grain size of 50 to 65. (3) In a rotary blade for agricultural machinery, in which blade portions are formed on both sides of a piece-like body provided with a mounting hole for mounting on a rotating shaft, a fine blade having a hardness of HRC40 to 45 is provided between the two blade portions. A heat-treated zone of pearlite structure is formed, and each of the parallel zone regions including the above-mentioned double edge portions has a hardness of H, C50.
A rotary blade for agricultural machinery, characterized in that a reheat treatment zone is formed with a martensitic structure having a grain size of 65 to 65. (4) In a rotary blade for agricultural machinery, in which blade portions are formed on both sides of a piece-shaped body provided with a mounting hole for mounting on a rotating shaft, a fine blade having a hardness of HRC 40 to 45 is provided between the two blade portions. A heat-treated zone of pearlite structure is formed, and each of the parallel zone regions including the above-mentioned double edge portions has a hardness of HRC50.
A reheat treatment zone of a martensitic structure having a hardness of H, C50 to 65 is formed between the mounting hole and the heat treatment zone of a fine pearlite structure, respectively. A rotary blade for agricultural machinery characterized by being formed. (5) In a rotary blade for agricultural machinery, in which blade portions are formed on three sides, ie, both sides and the end surface of a piece-shaped body provided with a mounting hole for mounting on a rotating shaft, the rotary blade is surrounded by the blade portions formed on the three sides of L. A heat treatment zone of a fine pearlite structure with a hardness of HRC 40 to 45 is formed in the part that has been removed, and a reheat treatment zone of a martensitic structure with a hardness of H+tC of 50 to 65 is formed in the U-shaped band region that includes the entire blade part. A rotary blade for agricultural machinery characterized by being formed. (6) In a rotary blade for agricultural machinery, in which blades are formed on three sides, ie, both sides and the end face of a piece-shaped body provided with a mounting hole for mounting on a rotating shaft, the blade is surrounded by the blades formed on the three sides. A heat treatment zone of a fine pearlite structure with a hardness of HRC 40 to 45 is formed in the part, and a reheat treatment zone of a martensitic structure with a hardness of HRC 50 to 65 is formed in the U-shaped band region that includes the entire blade part. A rotary blade for an agricultural implement, further comprising: a reheat treatment zone of a martensitic structure having a hardness of HRC 50 to 65 formed between the mounting hole and the heat treatment zone of the fine burlite T411i.