JPH0367520A - Hydraulic driving type bush cutter - Google Patents

Abstract

PURPOSE:To rapidly, safely and readily stop rotation of cutting blades by opening and closing an oil feed pipe and oil return pipe from a hydraulic pump and simultaneously providing a changeover valve capable of communicating the pipes through a narrow passage. CONSTITUTION:An oil feed pipe (3a) and an oil return pipe (4a) from a hydraulic pump driven with a prime mover 1 are respectively connectedly provided on the side of the outer periphery of turbine blades in a cutting blade rotating case 6. A changeover valve casing (10a) is interposingly provided with a changeover valve for opening or closing both pipes (3a) and (4a), communicating the pipes (3a) and (4a) on the side of the turbine blades through as narrow passage in closing and normally communicating the pipes (3a) and (4a) on the side of the hydraulic pump.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application 1 The present invention relates to a hydraulically driven coupon machine whose cutting blades can be rotationally driven by hydraulic pressure.

1. Prior Art 1. Conventional brush cutters of this type have a structure in which power is transmitted from a transmission shaft driven by an internal combustion engine or an electric motor to a gear case to mechanically drive the cutting blade to rotate.

[Problem to be solved by the invention] In such a mechanical structure, a long transmission shaft is supported at several locations inside a long operating rod, resulting in a complicated transmission structure and a large number of parts, making it difficult to process and introduce. It is difficult and increases the cost, and it also generates vibration and noise, making it difficult to operate.Also, due to the mechanical structure, it is difficult to stop the cutting blade quickly and safely in an emergency without straining the transmission part. The problem was that it was not possible to do so.

1. Means for Solving the Problem] The present invention solves such problems and makes it possible to effectively rotate the cutting blade using hydraulic pressure and stop it quickly and safely. A feed 1h pipe and an oil return pipe extending from a hydraulic pump driven by a prime mover are connected to the outer periphery of a turbine blade in a case that rotates a cutting blade, and the feed pipe and oil return pipe are connected to each other. The connecting part (,7 has
A switching valve is installed that can open and close the pipes on both sides, and when closed, allows communication between both pipes on the turbine blade side through a narrow passage and allows normal communication between both pipes on the hydraulic pump side. It is composed of

1 Effect 1 Therefore, when the oil supply pipe and the M1 return pipe are respectively opened by the switching valve, the cutting blade can be efficiently rotated and the interest payment work can be performed without rotating the turbine blades by hydraulic pressure. In addition, if the switching valves are used to close the pipes on both sides, the flow from the hydraulic pump will flow back without any hindrance, and the flow of the flow back from the turbine blades, which rotate due to inertia, will be restricted as it passes through the narrow passage. Therefore, the brake is applied to the turbine blade, and the cutting blade can be quickly, safely and easily brought to a stop +Th without stopping the hydraulic pump.

[Example] Next, the embodiment shown in the drawings will be described.

FIG. 1 shows a side view of the entire hydraulically driven brush cutter. On the back support (12) side, there is a prime mover (1) and a prime mover (1) on the shoulder frame (14), which has both shoulder straps (13). The switching valve box (2) is equipped with a hydraulic pump (2) that is directly connected and driven, and is connected to the rear end of the long round pipe operation rod (5).
10a) and the hydraulic pump (2), a flexible sending pipe (3a) and an oil return pipe (4a) were connected to the front end of the operating rod (5), respectively. A rotating shaft (15) having a turbine blade (7) on the upper part is mounted inside the case (6), and a cutting blade covered with a safety cover (16) is mounted on the lower end of the rotating shaft (15). (8)
is fixedly installed, and the oil sending pipe (3b) and oil return pipe (4a) extending from the switching valve box (lOa) are connected to the operating rod (5).
) and insert both pipes (3b
) (4b) are connected to the outer circumferential side of the turbine blade (7), and the turbine blade (4b) is heated by the Ah pressure.
The cutting blade (6) is configured to be rotationally driven without rotating the cutting blade (7).

Furthermore, a rubber grip (17) that can be gripped with one hand is fitted to the rear of the operating rod (5), and a handle (18) that can be gripped with the other hand is fitted on the front side. A throttle lever (11), which can be operated with one hand holding the grip (17), is attached to a fulcrum shaft at the rear of the latch (19), which is fixed to the grip (17) by a fixing band (19a) in front of the grip (17). (zo), extends from the front arm (lla) of the throttle lever (11) into the latch (1g), and consists of an inner (22a) and an outer (22b) with a spring (21) interposed therebetween. The wire (22) is interlocked with the throttle of the prime mover (+), and the structure is such that mowing work can be carried out by carrying the carrying frame (14) on one's back.

In addition, (17a) shows a rubber damper part provided on the grip (17), and when the throttle/nottle lever (11) is pressed into contact with it by gripping it more strongly than when it is in contact with it, the rubber damper part 07a) deforms and the throttle The lever (11) is configured to rotate and pull the inner wire (33a) of the brake Bowden wire (33).

At the rear of the upper part of the switching valve box (10a), there are formed two parallel structures (23a) and (24a) in the front and rear direction that communicate with the oil sending pipe (3a) and the oil return pipe (4a), and at the front. Both extraction passages (2
3b) (24b) and an O ring (25) on the outer periphery.
(25) is fitted into the switching valve box (10a), and the oil passage (23) is installed in the upper part of the switching valve (10).
a) (23b) and (24a) Both mll tracts (26a) parallel in the anteroposterior direction that can match (24b), respectively
(26b), and the switching valve (10
), a horizontal oil passage (9a) is formed in the front part of the oil passage (zsb) (24b) with both ends thereof communicating with each other and having a narrow passage (0) in the middle part, and a switching valve that is behind it. (lO)
A lateral oil passage (27) is formed in the rear part of the oil passage (27), both ends of which communicate with the oil passages (23a) and (24a).
Ru.

In addition, a compression spring (28) is fitted below the switching valve (lO) between the inner bottom of the switching valve box (lea) and the switching valve (lO), and an upper end is fitted to the outer periphery of the switching valve (lO). The outer circumference of the switching valve box (10a) is pressed toward the engagement groove (29) by the spring (30). The engagement pin (31) is inserted into the front arm (lla) of the throttle lever (11).
) extends into the latch (19) from the lower end side of the spring (32), which has a weaker spring force than the throttle wire spring (21).
) interposed between the inner (33a) and outer (33a)
The other end of the Bowden wire (33>) is interlocked with the outer end of the engagement pin (31>) from b), and the throttle can be adjusted by slightly moving the throttle lever (11) up and down. 17) Rubber damper (1
When 7a) is moved up significantly so that it deforms, the engagement pin (
31) is installed and configured so that it can be operated.

Therefore, while carrying the prime mover (1) etc. on your back, grip the grip (17) with one hand, and hold the handle (17) with the other hand.
This means that the mowing work can be performed while holding the lever (M) and operating the operating rod (5), and as shown in FIGS. 29)
When the switching valve (10) is pushed down until it fits into the folded end (29a) and engages II', the throttle lever (1
1), by operating the hydraulic pump (2) at the same rotation speed of R-movement m(1) of 211L, the turbine blade (7 ) can rotate the cutting blade 0), and the oil will flow back to the hydraulic pump (2).

To stop the cutting blade (0), press the throttle lever (1
1) in the direction of arrow (A), the engagement pin (31) is pulled by the operation of the Bowden wire (33), as shown in Figs. 7 and 8. The switching valve <IO> will move up, so the 7th
Hydraulic pump (2) as shown by the arrow in between and FIG.
The oil flows back through the oil passage (27) without any problems, and the return flow from the turbine blade (7), which rotates due to inertia, is restricted when passing through the narrow passage 0). As a result, the turbine blade (7) is effectively braked, and the mower blade (8) can be quickly, safely and easily stopped without stopping the hydraulic pump (2). Become.

Note that the switching valve (lO) can also be configured so that it can be switched by another operating lever other than the throttle lever (11).

Furthermore, the extraction pump (2) that is directly connected to the prime mover (1) is removed from the backpack frame (14), and the prime mover (1) is
), or by fixing one end of the operating rod (5) to the extraction pump (2) directly connected to the prime mover (1), and extending a hanging fitting using a hydraulic pump (2), etc. The objects and effects of the present invention can also be achieved even if the structure is suspended.

[Effect of the invention 1] As described above, the present invention can efficiently rotate the cutting blade (0) while simultaneously rotating the turbine blade (7) using the hydraulic pressure from the hydraulic pump (2), thereby reducing vibrations in the machine body. This means that mowing work can be performed with good operability by preventing this from occurring, and by operating the switching valve (lO), the turbine blade (
7) Rapidly regulate the flow pressure of 11h flowing back, apply a brake to the turbine blade (7), and
Safely, easily and quickly remove the cutting blade (
8) can be stopped from rotating, and as a brush cutter that can drive the cutting blade (8) by hydraulic pressure, it has the advantage of being easy to operate and can be suitably implemented with a simple structure.

[Brief explanation of drawings]

Fig. 1 is a side view of a hydraulically driven brush cutter as an example;
3 is a plan view of a portion of FIG. 1, FIG. 4 is a sectional view of a portion of FIG. 1, and FIG. 5 is a side sectional view of the switching valve. FIG. 6 is a plan sectional view of a part thereof, FIGS. 7 and 8 are explanatory diagrams of the operation in FIGS. 5 and 6, respectively, and FIGS. 9 and 10 are IX-IX in FIG. 8. FIG. 3 shows a side view of a portion of the switching valve seen from the line and the line X-X, respectively. (1)... Prime mover (3a) (3b)...
・Oil feed pipe (4a) (4b)...Oil return pipe (6)...Case (7)...Turbine blade 0)...Cutter blade 0)...Narrow passage (1)
0)...Switching valve

Claims (1)

[Claims] The oil sending pipes (3a) (3b) and the oil return pipes (4a) (4b) extending from the hydraulic pump (2) driven by the prime mover (1) are connected to the case where the cutting blade (8) is rotated (
6) are connected to the outer circumferential sides of the turbine blades (7) in the interior, and pipes on both sides are connected to the respective connecting parts of the oil sending pipes (3a) (3b) and the oil return pipes (4a) (4b). It can be opened and closed, and when closed, both pipes (3b) (4b) on the turbine blade (7) side are communicated via a narrow passage (9), and both pipes (3a) (4a) on the hydraulic pump (2) side are connected. ) A hydraulically driven brush cutter is characterized in that it is constructed by interposing a switching valve (10) that allows normal communication between the two.