JP2005287306A - Automatic sharpening of blade for reaping - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To facilitate sharpening operation of a reaping blade used for bush cutters and mowing machines and keep the cutting sharpness of the reaping blade even when number of rotation of the reaping blade is lowered and prevent various kinds of accidents caused by excessive centrifugal force. <P>SOLUTION: The direction of a surface 1 for sharpening the reaping blade which has mainly been carried out hitherto in nearly radial direction is changed in circumferential direction at outer periphery of the reaping blade and a plurality of notch parts 2 are provided in the outer peripheral part to facilitate the sharpening of the reaping blade and not reducing the cutting sharpness. The reaping blade enables automatic sharpening by using torque of the reaping blade. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

The present invention enables automatic sharpening of a cutting blade of a mower or the like.

Various blades used in brush cutters and mowers have been devised and used for the purpose of safety, sharpness, sustainability, etc., such as saw blades, scissors blades, tipsaws, 8 blades, nylon cords, steel wires, resin plates, etc. It was.

As prior art
JP 2000-197406 A JP 2001-128530 A JP-A-9-298925 and the like.

Sharpness, sharpness maintenance, ease of sharpening, sharpening unnecessary, prevention of accidents caused by centrifugal force (accidents caused by hitting pebbles, etc., or scattering of damage due to centrifugal force of the blade itself) There are still many things that can satisfy all of them. In recent years, the use of tipsaws and nylon cords tends to increase despite the high demand for unobtrusiveness and poor sharpness and energy consumption.

However, many problems remain, such as accidents caused by flying pebbles by turning the cutting blade at high speed, damage to the chip itself, and reduction in energy efficiency.

The present invention has been made in view of the above circumstances, and facilitates sharpening work and maintains sharpness even when the rotational speed of the cutting blade is lowered, thereby preventing various accidents due to excessive centrifugal force.

The cutting edge of the cutting blade that has been mainly in the radial direction in the past is the circumferential direction of the outer periphery of the cutting blade, and a plurality of notches are provided on the outer peripheral portion to make the cutting blade easy to sharpen and not sharp. , Allowing further automatic sharpening.

Safe work can be realized with low rotation, low energy, and low noise by minimizing the cross-sectional area of grass and the like cut by the blade.

The shape of the cutting blade is determined so that the shape of the cutting blade can be sharpened by rotating the outer peripheral portion of the cutting blade to form a sharp portion, and a large number of tip portions 3a are provided.

1, the sharpening surface 1 forms a conical surface from the outer periphery of the cutting blade toward the center, and the blade portion 3 is formed along the outer peripheral surface. The blade tip 3a is formed by a plurality of grooves 2 set. FIG. 2 is a perspective view seen from above, and the upper surface 5 is hard chrome plated or the like so that a sharp sharpened portion can be maintained for a long time. A tough material is selected as the base material of the blade.

3, 11 is a nylon cord, 12 is an 8-blade, when the blade is worn, 13 is an 8-blade sharpening, 14 is a tip saw, and the area cut by each blade edge is shown in FIG. It can be seen that the area 10 is particularly small (shown at the same scale). Similarly, 16 to 19 show how much area the conventional cutting blade cuts in one rotation. The total 15 of the cross-sectional area per one rotation of the present plan is as small as 18 when the 8-blade is new, and this size is not changed even when worn like the 8-blade.

Further, when the outer peripheral portion 3 is worn away, the conspicuous work is completed by simply applying the outer peripheral portion to a grindstone or the like while turning the cutting blade with the engine. When there is no grindstone or file, just rub against the soil, the relatively soft steel part will be worn away, and the hard chrome plating layer will remain sharp so that a new outer peripheral edge can be formed. It becomes possible to make a model.

In FIG. 4, the cross-sectional shape of the cutting blade is formed into a shallow dish shape, a plurality of cutout portions 2 are formed in the portion that contacts the edge of the dish, a cutting blade is formed, and the sharp surface obtained by processing the upper surface 1 is obtained. The outer peripheral part 3a is used as a blade.

As shown in FIG. 5, the cutting blade formed in this way is pressed by the gravity stone 55 attached to the tip of the grinding wheel holder 51 along the guide member 52 fixed to the cutting blade cover 54 in the direction 53 by gravity. The flat surface 1 of the outer peripheral portion of the blade is processed. Since the cutting blade 10 can be rotated by an engine or the like, the dressing operation can be performed without removing the cutting blade from the body, so that it is not necessary to carry a cutting blade spare.

This dish-shaped cutting blade is less likely to cut the soil if it is directed upward as described above, and it becomes easy to cut a certain length, and if it is used downward, it cuts the root of the grass, so-called grass weeding state It can be used for a wide range of applications, such as reducing the time and effort of weed treatment.

Compared to tip saws and nylon cords brazed with cemented carbide tips, etc., sharpness, low rotation work, low noise, less fatigue, and problems such as splashing pebbles due to excessive high speed rotation The cutting blade of the present plan that can be prevented and that is easy to sharpen is highly energy-saving and is expected to be widely spread. In addition, it has a feature that the sharpening work is easy with respect to the conventional scissors blade or 8 blades, and the workability is less deteriorated due to wear of the tip.

Schematic view of the cutting blade of this plan as seen from below Entity diagram of the cutting blade of this plan as seen from above Schematic diagram of the area cut by one blade of various cutting blades and the area cut by the entire blade in one rotation Entity diagram of Example 2 as viewed from diagonally above Cross-sectional explanatory drawing of automatic sharpening part Illustration when not using automatic sharpening Entity diagram of conventional tip saw viewed from above An enlarged diagram of the conventional 8-blade part with blades showing the sharpened state in the radial direction

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Sharpening surface on the circumference of a cutting blade 2 Groove part 3 which forms the front-end | tip 3a of a blade 3 Circular blade part 3a Sharp edge part 4 of a cutting blade 4 Mounting hole 5 Hard chrome plating part given to a cutting blade 6 Lightening meat hole 7 Body contact member 10 Area cut with one blade of this plan (triangle with width 0.3 and height 0.2)
11 Cross-sectional area that nylon cord cuts once (same scale as above)
12 Cross-sectional area cut by one blade when the eight-blade cutting blade is worn 13 Cross-sectional area cut by one blade when the eight-blade cutting blade is sharpened 14 One carbide blade is cut by one Area 15 The area of the proposed blade cut by one rotation (40 sheets) 16 The cross-sectional area of the nylon cord cut by one rotation (two scales as above)
17 Cross-sectional area cut by one rotation of the blade when the eight-blade cutting blade is worn 18 Cross-sectional area cut by one rotation of the blade when the eight-blade cutting blade is sharpened 19 One-turn rotation of the carbide tip saw blade Area to cut (20 blades)
21 Tip of conventional carbide tip saw 21a Tip end portion 31 of conventional carbide tip saw 31 Sharpening blade portion 31a of eight blades Tip portion 50 of eight blades 51 Representing the entire cutting blade 51 Grindstone holder 52 Guide member 53 The direction of force Shown arrow 54 Cutting blade cover 55 Whetstone 56 Blown plug

Claims (3)

A blade of a mowing device or a lawn mower characterized by selecting a surface formed by rotating the sharpening surface of the cutting blade and forming a cutting blade by providing a plurality of notches on the outer periphery. The blade of the mowing apparatus or lawn mower characterized by having a hard film such as hard chrome plating attached to the surface A sharp outer periphery obtained by forming the cutting blade into a shallow dish shape, forming a cutting blade by providing a plurality of notches 2 at the portion of the dish that touches the edge of the dish, and processing the outer peripheral surface 1 A blade of the mowing apparatus or lawn mower using the portion as a blade. The cutting blade that can be sharpened by the sharpening members 51, 55, etc., in which the dish-shaped cutting blade is mounted on a mowing cover.