JPH0746101Y2 - Reciprocating brush cutter - Google Patents

Description

TECHNICAL FIELD The present invention relates to a reciprocating brush cutter.

2. Description of the Related Art A reciprocating brush cutter is, for example, a machine that reciprocates a pair of slender sliding cutting blades provided at a head portion of the tip of an operating rod in opposite directions in the length direction to perform mowing work. In the head portion, there is provided a driving force conversion mechanism that converts a rotational driving force from a power source such as an internal combustion engine into a reciprocating driving force to reciprocally drive the cutting blade. In this type of conventional brush cutter, since the cutting blade itself protrudes from the head portion to the outside,
It is necessary to provide a fairly large opening in the head section, and rainwater and mowed grass can easily enter the head section through this opening.
In addition, since the driving force conversion mechanism is located on the same plane as the cutting blade, it is difficult to ensure waterproofness.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a reciprocating brush cutter having a simple and convenient shape while solving the problems of the conventional techniques described above.

Means for Solving the Problems That is, according to the present invention, a driving force conversion for reciprocally driving a sliding cutting blade by converting a rotational driving force of a rotary driving shaft provided in a head portion of a brush cutter into a reciprocating driving force. A reciprocating brush cutter having a mechanism rotatably supports a rotating shaft of the driving force converting mechanism on the head portion, projects the rotating shaft from the head portion to the outside, and drives a gear, an eccentric cam and a cam follower. The rotary shaft is drivingly connected to the rotary drive shaft via a child to drive the rotary shaft, one end of the swing arm is fixed to an outer end of the rotary shaft, and the other end of the swing arm is fixed to the outer end. It is characterized by being engaged with a sliding blade.

Therefore, the only part that penetrates the wall of the head part and projects to the outside is the rotating shaft, so that the head part can be easily completely sealed, and the drive force conversion mechanism can be separated from the cutting plane. You can

Embodiment Next, the present invention will be described based on an embodiment of the drawings.

First, in the embodiment shown in FIG. 1 and FIG. 2, in the head portion 1 attached to the tip of the operating rod P of the brush cutter, the tip portion of the rotary drive shaft 2 extending through the inside of the operating rod P is a bearing. It is rotatably supported by 3. The driving force conversion mechanism 4 that converts the rotational driving force of the rotary driving shaft 2 into a reciprocating driving force to reciprocally drive the pair of sliding cutting blades is configured as follows. That is, a drive bevel gear 5 is attached to the tip end portion of the rotary drive shaft 2, and a driven bevel gear 6 is meshed with the drive bevel gear 5, and the driven bevel gear 6 moves horizontally in the head portion 1. It is rotatably supported by a shaft 7 extending in the direction of bearings 8 and 9. Further, the driven bevel gear 6 is formed with a pair of eccentric cams 10 and 11 as one body.
1 is 180 degrees out of phase with each other, and each eccentric cam
The cam follower 13 and 10 through 11 through a number of rollers 12.
14 engaged. These cam followers 13 and 14 integrally have arm portions 15 extending in opposite lateral directions,
The tip of the arm 15 is pivotally attached to the upper end of the internal swing arm 17 '. A lower end portion of the internal swing arm 17 'is fixed to a rotary shaft 16 rotatably supported in the head portion 1, and a tip end portion of the rotary shaft 16 has the head portion 1'. It projects from the wall to the outside. An upper end portion of an external swing arm 17 is fixed to an outer end of the rotating shaft 16, and a lower end portion of the external swing arm 17 is fitted to a concave receiving portion 18 of one swing cutting blade 18. The sliding cutting blade 18 is reciprocated in the length direction by the swing of the external swing arm 17. The mechanism for driving the other cam follower 13 from the other cam follower 13 is not shown, but it is described above from the cam follower 13 to one cutting blade 18
It is formed in the same way as the mechanism that drives, and operates by reversing the phase by 180 degrees. As described above, since only the pivot shaft 16 is the only part that protrudes to the outside through the wall of the head part 1, the head part 1 is easily formed in a sealed structure so as to completely isolate the inside from the outside.

Incidentally, as shown in FIG. 1, the operating rod P side of the head portion 1 and the swing arm 17 are divided and the angle can be further varied around the pivot 7 to further improve the workability.

Next, the embodiment shown in FIG. 3 and FIG.
A drive force conversion mechanism 20 provided in 19 includes a drive spur gear 22 attached to a rotary drive shaft 21, and a pair of driven spur gears that are respectively arranged on both sides of the drive spur gear 22 and mesh with the drive spur gear 22. Gears 23 and 24, eccentric cams 25 and 26 integrally formed with the driven spur gears 23 and 24, respectively, and the eccentric cam 25 and
Cam followers 29 and 30 respectively having arm portions 27 and 28 respectively engaged with 26 and extending in opposite directions on both sides,
The tips of the arms 27 and 28 are fixed, and the head 19 is fixed.
Pivoting shafts 31 and 32 that are rotatably supported by the head unit 19 and project to the outside of the front of the head unit 19. The cutting blades 33 and 34 are constituted by a pair of swing arms 35 and 36 fitted into the receiving portions 33 'and 34'. Also in this embodiment, since only the rotating shafts 31 and 32 project from the head portion 19 to the outside, the inside of the head portion 19 can be completely sealed.

Further, in the embodiment shown in FIG. 5, the driving force converting mechanism 38 provided in the head portion 37 of the worm 40 is mounted on the rotary drive shaft 39, and a pair of worm gears meshed with the worm 40 on both sides of the worm 40. 41 and 42 and the worm gear
Eccentric cams 43 and 44 integrally formed with 41 and 42, respectively
Cam followers 45 and 46 respectively engaged with the cam followers 45 and 46, and arm portions 47 extending from the cam followers 45 and 46 to opposite sides in opposite directions, respectively.
And internal swing arms 53 'and 54' pivotally attached to the tips of 48 and 48,
Rotating shafts 49 and 50 for fixing the inner swing arms 53 'and 54' respectively and rotatably supported by the head portion 37 and projecting outward from the head portion 37 to the outside, and the rotating shafts 49 and 50. The upper end portion is fixed to the outer end of 50, and the lower end portion is constituted by rocking arms 53 and 54 fitted to the receiving portions 51 'and 52' of the pair of sliding cutting blades 51 and 52, respectively. There is. Also in this embodiment, the parts protruding from the head portion 37 to the outside are the rotating shaft 49 and
With only 50, the head part 37 can be completely sealed.

In any of the above examples, the sliding cutting blade is arranged in the horizontal direction orthogonal to the head portion,
If necessary, they can be arranged so as to be inclined vertically.

Effect of the Invention With the configuration of the present invention described above, the present invention completely seals the head portion and completely isolates the driving force conversion mechanism arranged in the head portion from the outside, and the working plane of the sliding cutting blade. The head section can be separated from the head section, the inside of the head section can be completely shielded from rainwater and grass, and the mechanism in the head section can be prevented from being soiled or corroded.

[Brief description of drawings]

FIG. 1 is a cutaway view of a head portion of a head portion of a reciprocating brush cutter showing an embodiment according to the present invention, and FIG. 2 is a II-I of FIG.
I is a broken view of the main part, FIG. 3 is a front view of the head part of a reciprocating brush cutter according to another embodiment of the present invention, FIG. 4 is a plan view of the main part of the head part of FIG. 3, and FIG. FIG. 5 is a schematic view of a head portion of a reciprocating brush cutter according to still another embodiment of the present invention. 1,19,37 …… Head part, 2,21,39 …… Rotary drive shaft, 4,20,3
8 …… Driving force conversion mechanism, 5,6,22,23,24,40,41,42 …… Gear, 10,11,25,26,43,44 …… Eccentric cam, 13,14,29,30 , 45,
46 …… Cam follower, 16,31,32,49,50 …… Rotating shaft, 17,35,
36,53,54 …… Swing arm, 18,33,34,51,52 …… Sliding brush blade.

Claims (1)

[Scope of utility model registration request] 1. A sliding cutting blade (18) which is provided in a head portion (1, 19, 37) of a brush cutter and converts a rotary driving force of a rotary driving shaft (2, 21, 39) into a reciprocating driving force. A reciprocating brush cutter having a driving force converting mechanism (4, 20, 38) for reciprocally driving the rotating shaft (16, 31, 32, 49, 5) of the driving force converting mechanism.
0) is rotatably supported on the head portion, and the rotating shaft is projected from the head portion to the outside to form a gear (5, 6, 22, 2).
3,24,40,41,42), eccentric cam (10,11,25,26,43,44) and cam follower (13,14,29,30,45,46) through the rotary drive shaft The rotary shaft is drivingly coupled to the rotary shaft for rotary drive, one end of the swing arm (17, 35, 36, 53, 54) is fixed to the outer end of the rotary shaft, and the other end of the swing arm is fixed. A reciprocating brush cutter having an end engaged with the sliding blade.