JPH06133620A - Bush cutter - Google Patents

Abstract

PURPOSE:To provide a simplified and refined bush cutter operable under self-propelling with the machine body supported by driven wheels. CONSTITUTION:Wheels 45 to be revolvably driven by the transmission section 18 branched from a cutting driving system are supported by a final case 39 provided revolvably around the vertical axial center Y for the machine body, and the final case 39 is revolved around the vertical axial center Y through the mechanical power transmitted via the transmission system of the branched transmission section 18 to the wheels 45 to ensure them to be turned. The above transmission system is also provided with normal rotation/contrarotation/neutral changeover mechanism; With the changeover operation, the wheels 45 are designed to turn taking advantage of normal rotation/contrarotation mechanical power. The above changeover mechanism is made up of (A) a frictional transmission surface 21 provided on the driving side and (B) a passive body 22 provided on the driven side with frictional passive surfaces 22a, 22b subject to pressure contact in an alternative way either in normal rotation or contrarotation state relatively to the frictional transmission surface 21.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a brush cutter configured to support a machine body by driving wheels so as to be self-propelled so as to be able to perform cutting work.

[0002]

2. Description of the Related Art A reaper, which is generally called a brush cutter, is provided with a cutting blade, which is axially supported on the tip of a trocar body, from an engine continuously connected to the rear portion of the trocar body. It is configured to be rotated by the power transmitted through the power transmission mechanism, and the worker hangs it with a shoulder strap and swings the hung body to the left and right to work while changing the position of the cutting blade. However, with this type of work,
The labor burden on the operator is great and it is difficult to work for a long time. Therefore, it has been proposed that the brush cutter is provided with a drive wheel, and the drive wheel can support the weight of the machine body to allow self-propelled reaping work by the ground rolling to reduce the burden on the operator (for example, (See Japanese Patent Publication No. 4-58927).

[0003]

The prior art of this type, as seen in the above-mentioned publication, is a traveling transmission linked to a drive source (electric motor) different from the engine for driving the cutting blade. The shaft is provided on the transmission shaft of the cutting blade drive system housed in the tubular body so as to interlock between the cutting blade and the engine with an inner / outer dual shaft structure, and the power transmitted through the traveling transmission shaft is used. Therefore, since it is configured to drive the wheels arranged in the bowl-shaped recess of the cutting blade disk, there are the following problems. In addition to requiring a drive source different from the engine for driving the cutting blade, a multi-axial structure is required for the transmission system housed from the tubular body to the transmission case at the tip end of the cutting body. It became complicated, and the weight also increased significantly, and it became expensive, so that the original aim of the brush cutter was to lose its light weight and low price. The present invention focuses on such a problem, and is carried out for the purpose of solving the problem, and the mowing work can be performed under the condition that the self-propelled worker supported by the driving wheels has a small burden. However, the present invention provides a brush cutter having a simple structure, a light weight, and a low price as compared with the conventional one.

[0004]

In order to achieve the above object, the brush cutter according to the present invention has a branch transmission section (18) branched from a mowing drive system (D) for driving a cutting blade (6). The drive wheels (45) (45) that are driven to rotate are supported by final cases (38) (39) rotatably provided around the longitudinal axis (Y) with respect to the machine body (1), and branched. The final case is generated by the power transmitted to the drive wheels via the transmission system of the transmission unit (18).
Drive wheels by rotating the wheels (38) (39) around the vertical axis (Y)
(45) (45) is configured to be turned. A forward / reverse / neutral switching transmission mechanism is provided in the transmission system of the branch transmission unit (18), and the forward / reverse / neutral switching transmission mechanism is switched to operate the forward / reverse power to drive wheels.
(45) (45) is preferably constructed so as to perform a turning operation. Further, the forward / reverse / neutral switching transmission mechanism interposed in the transmission system of the branch transmission unit (18) has a friction transmission surface (21) provided on the drive side (19) and a positive transmission with respect to the friction transmission surface (21). The friction passive surface (22a) (2a) (2
2b) and a passive body (2) mounted on the driven side (23).
2) is advantageous in that the branch transmission can be made compact.

[0005]

Embodiments of the present invention will be described with reference to the drawings. 1 is a partially broken side view of the brush cutter, FIG. 2 is a plan view of the brush cutter, FIG. 3 is a sectional view of the branch transmission portion, FIG. 4 is a sectional view of the branch transmission portion taken along line AA, and FIG. FIG. 6 is an explanatory view showing a turning mode of wheels, FIG. 6 is a partial plan view showing a positioning mechanism, FIG. 7 is a partial sectional view thereof, and FIG. 8 is an explanatory view showing a working state of a brush cutter according to the present invention.

In the figure, (1) is a machine body, and a base cylinder portion
(1a) and a long tube part (1
The main body is a tubular body composed of b). Then, the long tubular portion (1b) is fitted in the base tubular portion (1a) by metal bearing, and the base tubular portion (1a) is fitted in the groove (2) formed by recessing the outer peripheral portion of the appropriate portion. Screw body screwed to the crocodile (3)
The base tube (1
It is provided so that it can freely rotate with respect to a).

A passive casing (4) is continuously provided at the tip of the long tubular portion (1b), and the vertical axis is supported by the inside of the passive casing (4) and projects downward.
The cutting blade (6) is fitted to (5), and the cutting blade (6) is housed in the base cylinder portion (1a) and the long cylinder portion (1b) of the machine body (1). ), And is driven to rotate by the power transmitted to the vertical axis (5). The detailed structure of the mowing drive system will be described later.

On the other hand, the rear end of the base cylinder (1a) is formed in the clutch housing (7), the engine (8) is connected to the clutch housing (7), and the output part of the engine is connected to the clutch housing (7). ) Is interlocked with the output shaft (10) through a centrifugal clutch (9) housed in (). (11) is a handlebar extended from the lower side of the engine.

The output shaft (10), as seen in FIG.
Bearings (12) and (13) are concentrically supported inside the base cylinder (1a), and the cutting drive shaft (14) is interlockingly coupled to the front end, and the cutting drive shaft (14) is attached to the long cylindrical portion. Passing through the inside of (1b)
Mowing drive system for thrusting into the case (4) and transmitting power to the transmission portion provided in the passive case to drive the vertical axis (5) to rotate.
(D) is configured.

Further, a branch output gear (15) is integrally formed at an intermediate portion of the output shaft (10) in the longitudinal direction. The base cylinder (1) corresponding to the lower side of the branch output gear (15)
A part of the wall of a) is cut off to form an opening (16),
A branch transmission case (17) is attached to the opening (16) with a communication window corresponding to the branch transmission case (17).
The base cylinder (1a) and the base cylinder (1a) are integrated to form a branch transmission section (18).

The branch transmission section (18) is constructed as shown in FIGS. 3 and 4. That is, from the opening (16) to the base cylinder
A gear (19) that enters into (1a) and is constantly meshed with the branch output gear (15) is provided with a branch transmission case parallel to the output shaft (10).
The gear (19) is rotatably supported by the pivot (20) provided on the crocodile (17), the boss portion of the gear (19) is extended forward, and the friction transmission surface (21) on the drive side is provided at the front end thereof. Is forming.

The friction transmission surface (2) of the gear (18) is
1) A pair of left and right frictional passive surfaces that can frictionally contact 1)
The passive body (22) provided with (22a) and (22b)
It is fitted and fixed to the rotary shaft (23) supported by the branch transmission case (17) orthogonal to (20), and the passive body (22) on the driven side is fitted with the shifter (24). By moving it in the axial direction of the rotary shaft (23), the friction passive surface (22a)
(22b) is alternatively pressed against the friction transmission surface (21) to rotate the rotary shaft.
(23) is rotated normally or reversely, and the friction passive surface (2
Both 2a and 22b are kept in a neutral position where they do not come into pressure contact with the friction transmission surface 20, so that power is not transmitted to the rotary shaft 23.

The shifter (24) is connected to an operating lever (56) provided at the proximal portion of the handle (11) via a connecting tool (57) such as a bowed wire, and the handle hand By operating the operation lever (56) in the section, switching operation can be performed with a slight force.

A small-diameter gear (25) is provided at a separate place of the rotary shaft 23, and the small-diameter gear (25) is provided with a large-diameter gear (27) of a driven shaft (26) provided parallel to the rotary shaft (23). ) Is always meshed. The left and right ends of the driven shaft (26) are projected to the outside on the left and right sides of the branch transmission case (17), and the drive bevel gears (28) and (29) are fitted and fixed to the respective protruding parts.

The drive bevel gears (28) and (29) are accommodated in and supported by support cases (30) and (31) which are fixed to the branch transmission case (17) at their upper ends and are provided obliquely outward and downward. In the case (30) (31), the driven bevel gears (32) (33) are constantly meshed with each other, and the driven bevel gears (32) (33) are fitted to the upper ends of the king pins (34) (35). It is fixed in place. The kingpins (34) (35) are
As shown in FIG. 4, an imaginary line extending each axis (Y) downward is a perpendicular line (Y1) passing through the center of the drive wheel at or near the grounding center of the drive wheel (45) described later. It is provided with a degree of inclination so that it intersects.

The respective kingpins (34) (35) are fitted into the support cases (30) (31) from below and are rotated in the central holes of the cylindrical portions (36) (37) which are rotatably supported. Freely supported, the cylinders (36) (37) are final cases (38) (39)
It is provided integrally with. And the final case
Bevel gears (40) and (41) are fitted and fixed to the lower ends of king pins (34) and (35) in (38) and (39), and each bevel gear (40) and (41) is located on the left and right axles (42) of the horizontal axis. It is always meshed with the final bevel gears (43) and (44) fitted in. Reference numeral (45) denotes drive wheels fitted to the left and right axles (42), respectively, and these drive wheels are supported by the tubular portions (36) and (37) of the final cases (38) and (39). King pin by rotating with respect to the case (30) (31)
It is possible to turn around the axes (Y) of (34) and (35).

However, in order to cause the left and right drive wheels (45) (45) to turn in the same manner, both final cases (3
8) (39) is provided with swing arms (46) (47), and both (42) (4
The connection body (48) communicates between 3), and the connection body (48)
A positioning mechanism (49) is provided between the branch transmission case and the branch transmission case (17).
Are provided (see FIGS. 5 to 7).

Positioning mechanism (49) shown in FIGS.
The branch transmission case (17) is provided with a pin (51) that is attached to the connecting body (48) so as to be able to move up and down in the vertical direction and is urged upward by a spring (50). Engage with the arcuate guide hole (53) of the regulation body (52) provided,
A restricting portion (53a) (53b) (53) in which a pin (51) with an upward advancing posture is provided at a predetermined portion of the arc-shaped guide hole (53).
When engaged with any of c), the support case (30) (3
The rotation of the cylinders (36) (37) with respect to (1) is prevented, and the drive wheels (45) (45) are not turned.

Then, the pin (51) is connected to a turning operation lever (55) provided at the proximal portion of the handle (11) through a connecting tool (54) such as a Bowden wire, and the handle hand By operating the turning operation lever (55) in the section, the pin (51) is retracted downward against the spring (50) to engage with the restricting sections (53a) (53b) (53c). The restriction section (53a) (5
When the engagement with 3b) and (53c) is released, the pin (51) can freely move along the arcuate guide hole (53). In this free movement state, the support case (30) ) (31) is allowed to rotate the tubular portions (36) and (37).

It should be noted that the turning operation lever (55) for retracting the pin (51) of the positioning mechanism (49) downward is not installed, and the connecting tool (54) connected to the pin (51) is used for the shifter described above. -When the operating lever (56) for operating the shifter is operated by directly or indirectly connecting to the operating lever (56) for operating,
The downward retraction of the pin (51) and the switching of the shifter (24) can be performed at appropriate timings, and such a configuration facilitates the operation. Further, the positioning mechanism (49) is not limited to the one shown in the drawing, but the cylinder portions (36) (37) may be arranged at a necessary time and position.
Any other structure may be used as long as it can be switched between a state in which the rotation of the is allowed and a state in which the rotation is restricted.

[0021]

In the brush cutter constructed as described above, when power is transmitted from the engine (8) to the output shaft (10), the power is transmitted to the vertical axis (5) through the mowing drive system and the mowing is performed. Blade (6)
While being driven to rotate, a part of it is branched from the branch output gear (15) of the output shaft (10) to the passive body (22), the small diameter gear (25),
Large diameter gear (27), driven shaft (26), drive bevel gear (28)
(29), Kingpin (34) (35), Bevel Gear (40)
(41) and the final bevel gears (43) and (44) are transmitted to the axles (42) and (42), and the drive wheels (45) and (45) are rotationally driven.

When the brush cutter is moved straight forward or backward, the guide pin (51) of the positioning mechanism (49) is used.
Is an arc-shaped guide hole, as shown by the solid line in FIG.
The final case (38) (39) is engaged with the restriction portion (53a) of the (52) and is fixed to the support case (30) (31) so as not to rotate, and the drive wheel (45). ) (45) is maintained in the front-back posture as shown by the solid line in FIG. 5 and by the phantom line in the lowermost diagram of FIG. Under this position, if the shift lever (56) is operated by the operation lever (56) to bring the friction passive surface of the passive body (22) into normal rotation transmission to press it against the friction transmission surface (21), Drive Bevel Gear (28)
From (29) to kingpin (34) (35), bevel gear (40)
(41), the power transmitted through the final bevel gears (43) and (44) rotates the axles (42) and (42) in the forward direction to drive the drive wheels (45) and (45) in the forward direction, and The dispenser runs straight ahead.

When the operation lever (56) is operated so that the friction passive surface of the passive body (22) is pressed against the friction transmission surface (21) in the reverse transmission state, the drive wheels (45) (45) are moved. Since the brush cutter is driven in the reverse direction, the brush cutter travels backward in a straight line. Further, when the operation lever (56) that keeps the shifter (24) in the neutral position is operated, all the friction passive surfaces of the passive body (22) are pressed against the friction transmission surface (21). The drive wheels 45, 45 are in a neutral state in which the drive wheels 45, 45 are idling.

Next, the case of performing the reaping work will be described. Drive wheels so that the brush cutter travels in a straight line
(45) If the turning operation lever (55) is grasped under the posture in which (45) is oriented forward and backward (the posture shown by the phantom line in the lowermost diagram of FIG. 8), positioning is performed. Mechanism (49)
Pin (51) of the circular arc guide hole (53) restricting portion (53a)
The final case (38) (39) can be rotated with respect to the support cases (30) (31) by being disengaged from the support case and moving along the arc-shaped guide hole (53). .

In this state, the operation lever (56) is operated to change the friction passive surface of the passive body (22) to the friction transmission surface (2).
Branched output gear of the output shaft (10) when it is pressed forward to 1)
The final case (3) is generated by the rotational force in the forward rotation direction transmitted from (15) to the axles (42) and (42) through the passive body (22) and the like.
8) The (39) side is turned counterclockwise around the axis of the kingpins (34) and (35), and the drive wheels (45) and (45) move as shown by the solid lines in the bottom diagram of FIG. The posture is diagonally left and forward.

Thus, when the drive wheels 45, 45 are in a predetermined turning state, the pin 51 that has moved along the arcuate guide hole 52 is aligned with the regulating portion 53b. It is positioned and advanced by the urging force of the spring (50) so as to engage with the restriction portion (53b), and the final case (38) (39) side is fixed to the support case (30) (31). . If the final cases (38) (39) are fixed in this way, the axles (42) (42) are rotated by the power transmitted from the branch output gear (15) through the passive body (22) and the like. Driving is started, and the driving wheels (45) (45) travel forward diagonally to the left front as shown by the arrow F in FIG. Mowing is carried out by (6).

In this way, when the end of the mowing process is reached or at any time, the turning operation lever (55) is gripped and operated, and the pin (51) of the positioning mechanism (49) is moved into the arc guide hole. When removed from the restriction portion (53b) of (53), the final cases (38) and (39) are rotatable with respect to the support cases (30) and (31), and the axles (42) ( King pin on the final case (38) (39) side by the power transmitted to 42)
(34) (35) is further turned counterclockwise around the axis,
As shown by the solid line in the middle diagram of FIG.
(45) In (45), the part that was located at the rear of the traveling direction so far becomes diagonally forward right, and at that time, the pin (5
1) matches the regulation section (53c) and the final case (3
8) and (39) are fixed to the support cases (30) and (31), and the passive body (22) is switched to the reverse rotation state by this posture, so that the drive wheels (45) and (45) are As shown by an arrow R in FIG. 8, the mowing operation is performed while traveling diagonally forward and rightward in the reverse rotation state.

When the end of the stroke traveling diagonally to the right front is reached or at any time, the pin (51) of the positioning mechanism (49) is removed from the regulating portion (53c) of the arcuate guide hole (53). By operating the operation lever (56), the passive body
If (22) is returned from the reverse rotation transmission state to the normal rotation transmission state,
As shown by the solid line in the uppermost drawing of FIG. 5, the drive wheels (45) (45) are changed to a posture in which the driving wheels (45) (45) are directed obliquely to the left front again, and the pin (51) is restricted by the restricting portion () of the arc-shaped guide hole (53). 53
The posture is maintained by being engaged with b), and the arrow F
As shown in, the cutting is performed while traveling forward diagonally to the left.

That is, the drive wheel is turned by the power transmitted to it, and diagonally left frontward traveling and obliquely right forward forward traveling in the reverse rotation state are repeated. It is done. The turning angle in zigzag running can be set to any angle by setting the positions of the restricting portions (53a) (53b) (53c) of the positioning mechanism (49) as desired. It is preferable to set the turning angle so that the drive wheels 45, 45 can be operated near the side, and the mowing operation can be performed while the brush cutter is advanced. Further, it is more and more convenient if the turning angle in zigzag traveling can be adjusted as necessary.

[0030]

As described above, in the brush cutter according to the present invention, the drive wheel (rotationally driven by the branch transmission portion 18 branched from the cutting drive system (D) for driving the cutting blade (6) ( Four
5) (45) is supported by the final case (38) (39) rotatably provided around the longitudinal axis (Y) with respect to the airframe (1), and the branch transmission section (18) is supported. The final case (38) (39) is rotated around the vertical axis (Y) by the power transmitted to the drive wheels via the transmission system to turn the drive wheels (45) (45). Therefore, while the entire brush cutter is supported by the drive wheels and self-propelled, it is possible to perform the mowing work with a small burden on the operator, but the separate drive source required by the same type of conventional one is no longer necessary. Since the transmission system accommodated from the tubular body of the machine body to the transmission case at the tip end does not need to have a multi-axis structure, the structure is simple, lightweight and compact, and the price is relatively low. And
Drive wheel (45) is used to change the direction of movement of the brush cutter during mowing work.
Since it is performed by using the power transmitted to (45), the operator's burden required for changing the moving direction of the brush cutter can be reduced, and long-time work can be performed with very little fatigue.

Further, a forward / reverse / neutral switching transmission mechanism is provided in the transmission system of the branch transmission section (18), and by switching the mechanism, the forward / reverse power is used to drive the drive wheel (45).
When (45) is configured to be turned, the turning operation of the drive wheels by using power is performed in a state in which there is little unnecessary movement, and the efficiency of the mowing work is improved. Further, a forward / reverse / neutral switching transmission mechanism interposed in the branch transmission portion (18) is provided on the drive side (19), and a friction transmission surface (21) and a friction transmission surface are provided.
Consists of a passive body (22) mounted on the driven side (23) having frictional passive surfaces (22a) and (22b) which are selectively pressed against the forward rotation state and the reverse rotation state with respect to (21). This is advantageous because the branch transmission unit and thus the entire brush cutter is kept compact.

[Brief description of drawings]

FIG. 1 is a partially cutaway side view of a brush cutter according to the present invention.

FIG. 2 is a plan view of the brush cutter according to the present invention.

FIG. 3 is a sectional view of a branch transmission portion of the brush cutter according to the present invention.

FIG. 4 is a sectional view taken along line AA of the branch transmission unit.

FIG. 5 is an explanatory view showing a turning mode of driving wheels.

FIG. 6 is a partial plan view showing an example of a positioning mechanism.

FIG. 7 is a partial sectional view showing an example of a positioning mechanism.

FIG. 8 is an explanatory view showing a working state of the brush cutter according to the present invention.

[Explanation of symbols]

 D Cutting drive system Y Vertical axis (axis of kingpin) 1 Airframe 6 Cutting blade 18 Branch transmission part 19 Drive side (gear) 21 Friction transmission surface 22 Passive body 22a Friction passive surface 22b Friction passive surface 23 Driven side (rotation axis) ) 38 final case 39 final case 45 drive wheel

Claims (3)

[Claims] 1. A drive wheel (45) (45), which is rotationally driven by a branch transmission section (18) branched from a cutting drive system (D) for driving a cutting blade (6), with respect to the machine body (1). Final case (38) (39) rotatably provided around the vertical axis (Y)
And the final case (38) (39) is rotated around the vertical axis (Y) by the power transmitted to the drive wheel through the transmission system of the branch transmission section (18). A brush cutter configured to turn (45). 2. A forward / reverse / neutral switching transmission mechanism is provided in a transmission system of a branch transmission section (18) branched from a cutting drive system (D) for driving a cutting blade (6), and the forward / reverse / neutral state is established. The drive wheel (45) (4
5) A brush cutter configured to perform a turning operation. 3. A forward / reverse / neutral switching transmission mechanism interposed in the transmission system of the branch transmission unit (18) is provided on the friction transmission surface (21) and the friction transmission surface (21) provided on the drive side (19). On the other hand, the friction passive surface (22a) is pressed against the forward rotation and the reverse rotation.
A passive body (2) equipped with (22b) and mounted on the driven side (23)
The brush cutter according to claim 2, which is constituted by 2) and.