JPH0654618A - Device for fixing bush cutting blade of bush cutter - Google Patents

Abstract

PURPOSE:To dispense with bolts, washers and bolt holders of a device for fixing a bush cutting blade and to actualize miniaturization, light weight and reduction in cost. CONSTITUTION:The lower part of a bush cutting blade shaft 55 is engaged with an upper holder 59, the bush cutting blade shaft is screwed with a male screw 57 formed at the bottom of the bush cutting blade shaft 55 and a lower holder 61 for sandwiching a bush cutting blade shaft 43 between the upper holder 59 and the lower holder and fixing the bush cutting blade shaft is installed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cutting blade mounting device for a brush cutter for cutting grass on the ground by a blade that rotates horizontally by driving a motor.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 9, a cutting blade mounting device for a brush cutter of this type has an upper holder for holding a cutting blade 3 at a lower portion of a vertical cutting blade shaft 1 which is rotated by the drive of a motor. 5 and the lower holder 7 are fitted together via a spline 9, and a bolt 1 that is screwed into a screw hole 11 formed in the lower end surface of the cutting blade shaft 1.
It was fixed by 3. In order to prevent the head of the bolt 13 from coming into contact with the ground and being damaged, the bolt cover 15 surrounding the head of the bolt 13 is fastened together.

The cutting blade shaft 1 is vertically supported by a bearing case 21 via bearings 17 and 19, and a bevel gear 25 is engaged with an angular shaft 23 formed near the upper end. A bevel gear 29, which is rotatably supported by the bearing case 21 via a bearing 27, meshes with the bevel gear 25, and one end of a transmission shaft 33 is engaged via a spline 31. The other end of the connecting pipe 35, one end of which is fixed to the bearing case 21, is fixed to the prime mover, and the transmission shaft 33 penetrates the inside to transmit the power of the prime mover to the bevel gear 25.

[0004]

The conventional cutting blade mounting device has a large number of parts, has a complicated structure, is difficult to manufacture and assemble, and is heavy.

[0005]

SUMMARY OF THE INVENTION The present invention eliminates bolts, washers, and bolt covers by screwing a lower holder into a male screw formed at the lower end of a cutting blade shaft.

[0006]

In the present invention, at the time of assembling, the upper holder is engaged with the lower end of the cutting blade shaft, and then the cutting blade is fitted and then the lower holder is screwed onto the cutting blade shaft so that the upper holder The cutting blade is clamped and fixed between them.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings.

FIG. 1 shows a general brush cutter. The other end of a connecting pipe 39, one end of which is fixed to a prime mover (engine in this embodiment) 37, is fixed to a bearing case 41, and the bearing case 41 has a cutting blade. 43 is rotatably supported in the horizontal direction.

A support frame 47 to which a shoulder strap 45 is connected is fixed to the front of the engine 37, and a handle 51 having grips 49, 49 and a buffer 53 are provided in the middle of the connecting pipe 39.
Is stuck.

2 and 3 show an embodiment of the present invention. An upper holder 59 for holding the cutting blade 43 on a male screw 57 formed on the lower portion of a cutting blade shaft 55 which is rotated by the drive of a motor 37. The screw holes 63, 63 of the lower holder 61 are screwed together, and the lower holder 61 is tightened and fixed by a tool (not shown) that engages with the notch side portion 65 formed on the outer periphery of the lower holder 61.

The cutting blade shaft 55 is vertically supported by the bearing case 41 via bearings 67 and 69, and a bevel gear 73 is engaged with an angular shaft 71 formed near the upper end. A bevel gear 77, which is rotatably supported by the bearing case 41 via a bearing 75, meshes with the bevel gear 73, and one end of a transmission shaft 79 is engaged via a spline 78. The transmission shaft 79 penetrates the inside of the connecting pipe 39 and transmits the power of the engine 37.

In assembling, the upper holder 59 is screwed to the lower end of the cutting blade shaft 55, then the cutting blade 43 is fitted, and then the lower holder 61 is screwed to the cutting blade shaft 55, and the upper holder 59 is screwed. The cutting blade 43 is fastened and fixed between the cutting blade 59 and the cutting blade 59. The operator hangs the shoulder strap 45 on the shoulder, holds the grips 49, 49 with both hands, and uses the cutting blade 43 rotated by the drive of the prime mover 37 to cut off grass on the ground.

FIG. 4 shows another embodiment of the present invention.
The upper holder 5 is attached to the spline 81 formed on the cutting blade shaft 55.
9 is engaged. In FIG. 5, the outer circumference of the lower holder 61 is formed in a hexagonal shape. 6 and 7 show a second embodiment of the lower holder 61.
The protrusion 83 is formed in the center of the lower surface of the No. 1. Figure 7
7A shows a hexagonal protrusion 83, FIG. 7B shows a lower holder 61 with cutouts 65 formed on the outer periphery, and FIG. 7C shows a hexagonal outer periphery of the lower holder 61. It was formed. FIG. 8 shows a third embodiment of the lower holder 61, in which a protruding portion 83 is formed at the center of the lower surface of the lower holder 61 and the lower end of the protruding portion 83 is closed.

[0014]

According to the present invention, the following effects are obtained.

(1) Bolts, washers, and bolt covers for mounting the cutting blade can be eliminated, and the size, weight, and
Low price can be implemented.

(2) The cutting blade can be easily assembled and replaced.

(3) The cutting height of grass can be reduced.

[Brief description of drawings]

FIG. 1 is a perspective view of a brush cutter.

FIG. 2 is a side sectional view of an embodiment of the present invention.

FIG. 3 is a bottom view of the lower holder.

FIG. 4 is a side sectional view of a second embodiment of the present invention.

FIG. 5 is a bottom view of another embodiment of the cutout side portion of the lower holder.

FIG. 6 is a side cross section of a second embodiment of the lower holder.

7A is a bottom view of the shape of the cutout side portion, FIG. 7B is the second embodiment, and FIG. 7C is the third embodiment.

FIG. 8 is a side sectional view of a third embodiment of the lower holder.

FIG. 9 is a perspective explanatory view of a conventional cutting blade mounting device.

[Explanation of symbols]

 37 Motor 43 Cutting blade 55 Cutting blade shaft 57 Male screw 59 Upper holder 61 Lower holder

Claims (1)

[Claims] 1. An upper holder 59 which engages with a lower portion of a vertical cutting blade shaft 55 which is rotated by driving a motor 37, and an upper screw 57 which is formed on a lower end of the cutting blade shaft 55 and is screwed to the upper portion. A cutting blade mounting device for a brush cutter, comprising a lower holder 61 for sandwiching and fixing the cutting blade 43 between the holder 59 and the holder 59.