JPH0520529U - Centrifugal rotary blade for mower - Google Patents

Abstract

(57) [Abstract] [Purpose] A rotatable cutting blade (2) that utilizes centrifugal force prevents damage to the blade due to obstacles, and helps to mow areas with obstacles and to slide smoothly on the ground or concrete surface. (EN) Provided is a rotary blade for a mowing machine which can be mowed, has good sharpness, does not need to sharpen the blade for a long period of time, has a large cutting width, and can reduce required horsepower. [Structure] A plurality of cutting blades (2) made of an extremely thin plate having appropriate elasticity and hardness are equidistant from the center of the rotary disc (1), and the intervals between the cutting blades (2) are equal. In order that the entire cutting blade (2) can be housed inside the outer edge of the rotary disc (1), it is rotatably attached to the rotary disc (1) having a mounting hole (4) at its center.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a rotary blade for a mower that protects the blade from obstacles, has a wide cutting width, and can be used with a small horsepower, and uses the centrifugal force generated by rotation.

[0002]

[Prior Art]

 Conventionally, rotary blades have been used for mowers, but in recent years, mowers that use nylon cords have come to be used as a convenient tool. A similar one is disclosed in FIG. 10 of Japanese Patent Laid-Open No. Sho 58-9612. .

[0003]

[Problems to be solved by the device]

 The blades of conventional rotary blades for mowers are damaged by obstacles, so weeds must be mowed avoiding obstacles. For example, weeds growing in the corners of concrete walls and roads can be cut. It was not possible, and when cutting concrete crevices and weeds growing on the ground, it was not possible to mow low, so it was unavoidable that high mowing was unavoidable, and with the exception of expensive and high-class items, general rotary blades Have drawbacks such as fast wear, frequent sharpening of blades, relatively large horsepower, and light household electric horsepower and battery-powered mowers that do not provide sufficient cutting width. ..

A grass mower using a nylon cord has a feature that it does not have any problem even if there is an obstacle and requires a small horsepower. However, the nylon cord is greatly worn, and thin and soft grass can be cut. Thick and hard mature grasses such as Adachi grass and that chrysanthemum can not be cut and cannot be used as a full-scale mower.

As a device similar to the present invention, there is a centrifugal cutting blade disclosed in FIG. 10 of JP-A-58-9612, but the rotation of the cutting blade is limited by a steady rest, and There is a drawback that the effect of protecting the blade from obstacles is not sufficient due to the fact that there is no radius on the tip.

The present invention eliminates these drawbacks, protects the blade from obstacles to prevent damage to the blade, maintains sharpness for a long time, and eliminates the need for sharpening the blade. However, it is possible to mow, and grass on the ground and concrete surfaces can be mowed low. (EN) A rotary blade characterized in that a large cutting width can be obtained even with small horsepower.

[0007]

[Means for Solving the Problems]

 Near the outer edge of the turntable (1), a plurality of retaining shafts (3) are provided at equal intervals on a circle centered on the center point of the turntable (1), and mounting holes (4) are provided in the center. Is empty. The power shaft of the mowing machine is passed through the mounting hole (4), and is fixed to the power shaft (10) of the mowing machine such as the turntable (1) so that it can be attached and detached by an appropriate means such as screwing. The shape of the stop shaft (3) is a bolt-like shape with no threaded portion, and appropriate means such as welding the lower part, caulking, and tightening with a screw can be used. It is fixed to. In order to balance the rotation, the plurality of stop shafts (3) are all equidistant from the center of the turntable (1), that is, on the circumference of the center of the turntable (1), and The stop shafts (3) are arranged at equal intervals.

When cutting grass, it is made of a thin plate of about 0.3 mm-0.8 mm made of metal, plastic, ceramic or the like having appropriate elasticity and hardness that does not bend or break when hitting an obstacle. Near the base end (2B) of the cutting blade (2), a stop shaft hole (3A) is opened, and the tip (2A) is rounded.

The cutting blade (2) is rotatably and axially attached to the rotating disk (1) through the retaining shaft (3) in the retaining shaft hole (3A). The length of the cutting blades (2) shall be the length at which the cutting blades (2) do not come into contact with each other when the cutting blades (2) are turned in the same direction until they stop. The width of the cutting blade (2) and the position of the stop shaft (3) are determined so that each cutting blade (2) does not go out of the outer edge of the rotary disc (1).

[0010]

[Action]

 The operation of the present invention will be described with reference to FIG. The turntable (1) is rotating in the direction of arrow A 1. Normally, the cutting blade (2) rotates in the direction of arrow A, the direction of rotation of the turntable (1), while being perpendicular to the circumference of rotation of the stop shaft (3) by the centrifugal force generated by the rotation, The grass is cut by the cutting blade (2). When the resistance when cutting grass is large, and when the cutting blade (2) hits an obstacle, the cutting blade (2) rotates in the direction of arrow B, the retracted cutting blade (2 '), and saves. Protect the cutting blade (2). After retracting, the cutting blade (2) returns to its original position at a right angle to the circumference of rotation by the centrifugal force generated by the rotation. Even if the cutting blade (2) hits an obstacle or receives resistance, the cutting blade (2) rotatably and lightly retracts, so the rotational speed of the turntable (1) is hardly affected, and It is possible to maintain the high speed rotation of the period.

When cutting grass, the cutting blade (2) receives resistance from the grass, but the cutting blade (2) also maintains a current state of the rotary blade (2) due to centrifugal force due to rotation (anti-resistance). It is called force). Due to the resistance from the grass, the cutting blade (2) is pushed in the direction of the arrow B and becomes oblique and exerts an anti-resistance force on the grass, and the leading edge (2C) and the tip (2A) move the grass. Disconnect. Such cutting methods are generally called drawing cutting and diagonal cutting, and are considered to be effective cutting methods. Since the cutting blade (2) rotates and retracts, it is not always cut at once, and sometimes it may come out by cutting the grass several times, but it is also a high speed rotation and it is not sensuous to me. For example, when the rotation speed of the rotary disc (1) in FIG. 1 is 3000 times / sec. Since three cutting blades (2) are attached to the rotary disc (1), the cutting blade (2) is grass, 1/300 0 seconds 3 times, 2/3000 = 1/1500 seconds 6 times, 3/3000 = 1/1000 9 seconds 9 seconds, too fast, if you could cut in 1 time, Are indistinguishable.

When the tip portion (2A) of the cutting blade (2) hits grass, the obstacle (11) in FIG. 12, the ground surface in FIG. 13, or the concrete surface (12), the tip portion (2 If 2A) is not rounded, it will be caught by grass, obstacles, etc., and will receive an impact, but since the tip (2A) of the present invention is rounded, the impact is slight and smooth. ..

[0013]

【Example】

 An embodiment of claim 2 will be described with reference to FIGS. According to claim 1, a thin blade of 0.3 mm-0.8 mm is used for the cutting blade (2), but when there are few obstacles and it is not necessary to mow low, strongly cut the cutting blade (2). There is a case that you want to cut it even more strongly by hitting it against you and cut it away. What meets this requirement is the one described in claim 2, which will be described with reference to FIG. Generally, a suitable thickness of the cutting blade (2) is about 1.0 mm-2.0 mm. The cutting blade (2D) is attached to the tip (2A) of the cutting blade (2) and the front edge (2C) excluding a part thereof. Compared with the cutting blade (2) of claim 1, the cutting blade (2) of this example has a large weight and a large inertial force, and is different from the cutting blade (2) of claim 1 in that the grass blade is more powerful. It can be cut and cut away.

An embodiment will be described with reference to FIG. 7 and FIG. The rotary disk (1) is provided with a rotary disk blade (9) on the outer edge thereof. The cutting of the grass is mainly performed by the cutting blade (2), and the blade (9) of the rotary blade is for its assistance and for preventing the grass from being wrapped around to some extent.

Various types of rotary discs (1) are conceivable. FIG. 7 shows a rotary disk (1) having a triangular shape suitable for providing the rotary disk (1) with a blade (9) of the rotary disk, and the weight of the rotary disk (1) is reduced, and the cut grass is excluded to the outside. A turntable (1) having such a shape is illustrated in FIG.

Various types of cutting blades (2) can be considered. The cutting blade (2) illustrated in FIG. 15 has a front edge portion (2C) as a saw blade. In the example shown in Fig. 16, the cutting blade (2) is a wire having appropriate elasticity and hardness, and the feeling of use is similar to that of using a nylon cord, but the nylon cord is Even the thin one has a diameter of about 1.8 mm, while the wire has a diameter of about 0.7 mm, and is harder than a nylon cord and cuts better than a nylon cord. The grass can be mowed, it wears down as it is used, the tip becomes needle-like, and it becomes easier to cut. The wear rate is much less than nylon cords. The material of the wire was too hard for the piano wire to be broken, and the wear of ordinary soft iron wire was severe, and suitable results from the experiment were spring wire and stainless wire. However, note that unlike when using nylon cords, it will cut immediately if it is not pivotally attached.

There are various methods for removably attaching the cutting blade (2), and FIG. 9 shows an example thereof.

In FIG. 10, the rotary disc (1) is divided into an upper rotary disc (1A) and a lower rotary disc (1B), and a cutting blade (2) is sandwiched between them so that the cutting blade (2) is rotatable. This shows the structure in which the cutting blade (2) is pivoted, so that the rotation of the cutting blade (2) is not obstructed by vertical obstacles, cut grass, etc. It's smooth.

FIG. 11 is a plan view showing a configuration of a centrifugal rotary blade in which the cutting blade (2) can freely rotate left and right by 360 ° without contacting anything. Not only the cutting blades (2) do not touch each other, but also the power shaft passing through the mounting hole (4) and the clasps of the cutting shaft (2) do not come into contact with anything, and can be freely rotated 360 degrees to the left and right. The centrifugal rotary blade configured to come out of rotation has a smooth rotation and quiet sound because there is nothing to hit the cutting blade (2) other than the grass to be mowed in use.

FIG. 17 is a sectional view of an embodiment of a structure for protecting the stop shaft (3) from the rotating cutting blade (2). When the centrifugal rotary blade is used, the cutting blade (2) vigorously rotates around the stop shaft (3) while coming into contact with the stop shaft (3) through the stop shaft hole (3A), and the cutting blade (2) Since it is made of a thin and hard material of 0.3 mm to 0.5 mm, the retaining shaft hole (3A) damages the retaining shaft (3). In order to protect the retaining shaft (3), an eyelet (8) having a sufficient thickness made of soft iron, copper, etc. which is a softer material than the retaining shaft (3) is crimped to the retaining shaft hole (3A). In this way, the contact area between the retaining shaft (3) and the retaining shaft hole (3A) increases, and the eyelet (8) is softer than the retaining shaft (3), so that the retaining shaft (3) is not damaged. Of course, the eyelet (8) is worn, but it is economical because the eyelet (8) or the cutting blade (2) can be replaced without damaging the retaining shaft (3).

When the front edge (2C) is bent downward in the direction of rotation of the turntable (1) and a cutting blade (2) shaped like the blade of a bamboo dragonfly with the direction of bending bent is used, The wind is generated upward, the grass is scattered after cutting, and the cutting blade (2) does not float up and bites into the grass.

[0022]

[Effect of the device]

 In the rotary blade of the present invention, the cutting blade (2) is rotatably mounted on the rotary disc (1) so that even if the cutting blade (2) hits the obstacle, the cutting blade is cut by the obstacle. (2) cannot be hurt.

Since the cutting blade (2) of the present invention is made of an extremely thin thin plate of about 0.3 mm to 0.8 mm, it is not necessary to attach the blade (2D), and the blade is punched by a press for mowing. Since it can be used, it is inexpensive, and when worn, the front edge (2C) and the tip (2A) will naturally have blades, so there is no need to sharpen the blades and it can be used for a long time as it is. Economical from.

The cutting blade (2) of the present invention is not damaged by obstacles and is made of a thin plate having appropriate elasticity and hardness, so that the cutting blade (2) is curved as shown in FIG. Since it can be rotated so that it can be rubbed on the ground surface or concrete surface, it can be used for playing fields, grasses on the road surface, especially grass with a low stiffness, which is not possible with ordinary mowers. It is possible to mow it as low as possible on the surface. At this time, since the tip (2A) is provided with an arm, it is possible to smoothly rotate on these surfaces. This is convenient because the blade will be naturally sharpened and sharpened by simply touching the tip (2A) lightly on a smooth concrete surface and spinning it idle.

The centrifugal rotary blade of the present invention has a thin plate shape when rotated, and the lightweight cutting blade (2) comes out to the outside by centrifugal force, so that the rotary disk (1) has a small diameter. It is characterized by a large turning radius, which is the cutting width. In other words, it has a large cutting width and is lightweight. Since the cutting blade (2) is light in weight and its outer side is particularly lightweight when rotating, the required horsepower and torque are reduced, and the cutting blade (2) rotates against the resistance. This tendency becomes even greater because the vehicle retreats and the resistance is reduced. By adopting the rotary blade of the present invention, a general mowing machine having a maximum horsepower of 1.6 horsepower and a regular horsepower of 1.0 horsepower and an exhaust air amount of about 30 cc saves fuel and cannot perform full-scale mowing conventionally. Full-scale mowing is possible even with electric and battery-type mowers of about 1/7 horsepower, which were limited to horticultural use.

[Brief description of drawings]

FIG. 1 is a plan view showing the overall configuration of the present invention.

FIG. 2 is a plan view of a cutting blade (2).

FIG. 3 is a partial cross-sectional view for explaining the present invention.

FIG. 4 is an explanatory view of the operation of the present invention.

FIG. 5 is a plan view of the cutting blade (2) according to claim 2.

FIG. 6 is a cross-sectional view taken along the line AA ′ of the cutting blade (2) according to claim 2.

FIG. 7 is a plan view of a turntable (1) according to claim 3.

FIG. 8 is a cross-sectional view taken along the line BB ′ of the rotating disk (1) according to claim 3.

FIG. 9 is a perspective view showing an embodiment in which the cutting blade (2) is detachably attached to the rotary disc (1) by a shaft.

FIG. 10 shows a rotary disc (1) having two upper and lower rotary discs (1A),
(1B) is a partial cross-sectional view showing an embodiment in which the rotary blade (2) is sandwiched between them and the shaft is stopped.

FIG. 11 is a plan view of an embodiment in which the cutting blade (2) can freely rotate about 360 °.

FIG. 12 is an explanatory view of the action of the present invention on an obstacle.

FIG. 13 is an explanatory view of the action of the present invention when mowing grass on the ground or concrete surface.

FIG. 14 is a plan view of an embodiment of a turntable (1).

FIG. 15 is a plan view of an embodiment in which the cutting blade (2) is provided with saw teeth.

FIG. 16 is a plan view of an example in which the cutting blade (2) is a wire having appropriate elasticity and hardness.

FIG. 17 is a cross-sectional view of an embodiment in which the fixing shaft hole (3A) of the cutting blade (2) is strengthened.

[Explanation of symbols]

(1) Rotating disc (1A) Upper rotating disc (1B) Lower rotating disc (2) Cutting blade (2 ') Retracted cutting blade (2A) Tip portion (2B) Base end portion (2C) Front edge portion (2D) Cutting blade (2R) A line indicating the range of rotation of the tip (2A) of the cutting blade (2H) Position assuming that the cutting blade (2) did not hit an obstacle (3) Stop shaft (3A ) Retaining shaft hole (4) Mounting hole (5) Lock nut (6) Screw part (6 ') Screw hole (7) Washer (8) Eyelet (9) Rotating blade (10) Mower power shaft (10) ') Power shaft stopper (11) Obstacle (12) Ground or concrete surface (A) Line indicating the rotating direction of the turntable (1) (B) Line indicating the retracting direction of the cutting blade (2)

Claims (3)

[Scope of utility model registration request] 1. A turntable (1) made of metal, plastic, ceramic or the like is close to an outer edge portion, and a plurality of stop shafts (3) are arranged on a circle centered on a center point of the turntable (1). Are equidistantly provided with a mounting hole (4) at the center. It is close to the base end (2B) of the cutting blade (2) made of a thin plate of about 0.3 mm-0.8 mm of metal, plastic, ceramic or the like having appropriate elasticity and hardness, and the stop shaft hole (3
A) is opened, and the tip (2A) is rounded. The cutting blade (2) has a retaining shaft (3) in the retaining shaft hole (3A).
It is rotatably attached to the turntable (1) through the shaft.
The lengths of the cutting blades (2) are such that the cutting blades (2) do not come into contact with each other when the cutting blades (2) are oriented in the same direction. Centrifugal rotary blade for a mower having a structure in which the width of the cutting blade (2) and the position of the stop shaft (3) are determined so as not to go out from the outer edge portion of (1). 2. The cutting blade (2) has an appropriate thickness and is cut into a front edge (2C) and a tip (2A) except for the vicinity of the base end (2B) of the front edge (2C). The centrifugal rotary blade for a mower according to claim 1, wherein a blade (2D) is provided. 3. The centrifugal rotary blade for a mower according to claim 1, wherein the rotary disc (1) is provided with a rotary disc blade (9) at an outer edge portion thereof.