Remote-controlled grass mower

Abstract

To provide a remote control type mower capable of preventing cut grass accumulated on a vehicle body from coming into contact with an engine exhaust pipe.SOLUTION: An engine E is mounted on a front portion of an upper surface of the engine base 15 such that an exhaust pipe 84 of the engine E is located forward of a front end of the engine base 15, and a forwardly downwardly inclined cover 85 is attached to the engine base 15 at a portion below the exhaust pipe 84 where the exhaust pipe 84 and the mowing deck 3 overlap each other at least in a plan view.SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] The present invention relates to a remotely operated grass cutter, and more particularly to a configuration that can prevent grass cuts and the like from coming into contact with a high-temperature engine exhaust pipe. [Background technology]

[0002] Conventionally, a remotely controlled mower capable of mowing even on steep slopes has been known, as disclosed in Patent Document 1 below. This mower has a rotary blade attached to a mowing deck located in the lower center of the vehicle body, and mowing is performed by power transmission from an engine. Also, as disclosed in Patent Document 2 below, a configuration is known in which an exhaust pipe, which becomes hot, is covered with a cover and an opening is provided at the bottom of the cover to prevent foreign matter from accumulating inside the cover in a work machine equipped with an engine. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2020-005554 [Patent Document 2] Japanese Patent Application Publication No. 2018-003681 Summary of the Invention [Problem to be solved by the invention]

[0004] In a grass trimmer, there is a risk that grass clippings will accumulate on the vehicle body and come into contact with the engine's exhaust pipe, resulting in a fire. In particular, in the remote-controlled grass trimmer described in Patent Document 1, the upper surface of the mowing deck is flat, and the engine is mounted above the mowing deck, so grass clippings may accumulate on the mowing deck and come into contact with the exhaust pipe. Furthermore, the engine base on which the engine is mounted also has a flat upper surface, which presents a problem of grass clippings easily accumulating. Depending on the engine's mounting position, grass clippings accumulated on the engine base may come into contact with the exhaust pipe. Furthermore, because remote-controlled grass trimmers are operated by an operator at a distance from the vehicle body, there is the inconvenience of it being difficult to notice grass clippings accumulating on the vehicle body or catching fire.

[0005] Furthermore, when a cover is provided on the exhaust pipe of a brush cutter engine, it is desirable to leave the bottom open to prevent grass clippings from accumulating inside the cover, as in Patent Document 2. However, in the remote-controlled brush cutter described above, because a grass cutting deck is provided below the exhaust pipe, there is a risk that grass clippings accumulated there will enter from below the cover and come into contact with the exhaust pipe.

[0006] SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to provide a remotely controlled grass cutter that can prevent grass clippings accumulated on the vehicle body from coming into contact with the engine exhaust pipe. [Means for solving the problem]

[0007] The invention described in claim 1 comprises a mowing deck 3 that can be raised and lowered in the abdominal area 61, approximately in the center of the front, rear, left and right of the vehicle body 5, an engine base 15 that is supported so that it can rotate freely left and right, an engine E is mounted on the front of the upper surface of the engine base 15 so that the exhaust pipe 84 of the engine E is positioned forward of the front end of the engine base 15, a cover 85 that slopes downwards towards the front is attached to the engine base 15 below the exhaust pipe 84 at least in the area where the exhaust pipe 84 and the mowing deck 3 overlap in a plan view, and the front end position of the cover 85 protrudes forward of the mowing deck 15. [Effects of the Invention]

[0008] According to the invention described in claim 1, a liftable mowing deck 3 is provided in the abdominal portion 61, which is approximately centered in the front-rear and left-right directions of the vehicle body 5. An engine base 15, which is supported so as to be freely rotatable left and right, is provided above the mowing deck 3. An engine E is mounted on the front of the upper surface of the engine base 15, with the exhaust pipe 84 of the engine E positioned forward of the front end of the engine base 15. This prevents grass clippings from coming into contact with the exhaust pipe 84 even if they accumulate on the engine base 15. Furthermore, a cover 85 with a downward slope forward is attached to the engine base 15 below the exhaust pipe 84, at least in a part where the exhaust pipe 84 and the mowing deck 3 overlap in a plan view. The front end of the cover 85 is configured to protrude forward of the mowing deck 15. This prevents grass clippings accumulated on the mowing deck 3 from coming into contact with the exhaust pipe 84 by the cover 85. In addition, because the cover 85 is configured with a downward slope forward, grass clippings on the cover 85 do not slide off and accumulate, preventing contact between the exhaust pipe 84 and the grass clippings. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. [Figure 2] FIG. 10 is a partial side view showing the change in the belt transmission mechanism caused by the lifting and lowering of the mowing deck. [Figure 3] FIG. 4 is a side view of the mower showing the attachment state of the mowing deck by the parallel links and the lifting and lowering operation. [Figure 4] FIG. 4 is a plan view of the brush cutter showing the belt transmission mechanism of the blade shaft. [Figure 5] FIG. 4 is a partial plan view showing a belt transmission mechanism and an operating mechanism of the mowing clutch. [Figure 6] FIG. 2 is a plan view of the brush cutter showing the generator transmission mechanism. [Figure 7] FIG. 4 is a front view showing the tilting and rotating state of the engine relative to the vehicle body when traveling on an inclined surface. [Figure 8] FIG. 10 is a partial side view showing the positional relationship between the cover and the grass cutting deck. [Figure 9] FIG. 4 is a partial plan view showing the positional relationship between the cover, the exhaust pipe, the engine base, and the vehicle body. DETAILED DESCRIPTION OF THE INVENTION

[0010] A remote-controlled brush cutter according to one embodiment of the present invention will be described with reference to the drawings. This remote-controlled brush cutter is equipped with a pair of left and right crawlers 4 made primarily of rubber, and is mounted at the upper rear end of the vehicle body 5. The vehicle body 5 is equipped with a travel motor M for driving the crawlers 4, a transmission case 22, and two controllers 23 (top and bottom) for driving and mowing the grass. The front end of the vehicle body 5 is equipped with an engine E for driving the blade shaft 2 of the mowing deck 3. The front and rear central portions of the vehicle body 5 are equipped with a battery for starting the engine E, a fuel tank 26, a battery 24b for driving the motor M, a generator 25 for charging the battery 24b, a rectifier box 101, and other components. The upper portion of the vehicle body 5 is equipped with guard pipes 27 at the front and rear ends and guard frames 28 (arch-shaped) that cover the middle of the vehicle body 5. A cover 29 is provided to protect the upper portions of the various onboard equipment.

[0011] The crawlers 4 are hung on end rollers 32, intermediate rollers 33, and a drive sprocket 34 at the rear end, which are arranged in the front-to-rear direction of left and right track frames 31 attached to support legs 30 that stand upright from both the left and right ends of the vehicle body 5.The left and right traveling motors M transmit rotation of the sprocket shafts 35 via transmission gears in the transmission case 22, thereby rotating the left and right crawlers 4 and enabling the vehicle to travel or steer.

[0012] The mowing deck 3, on which the blade shaft 2 of the blade 1 that cuts grass is mounted, is detachably attached by link shafts 36, 37 to the rear ends of parallel links 8, 9 that move up and down, in the abdominal portion 61, which is approximately centered between the front, rear, and left and right of the vehicle body 5. The front ends of these parallel links 8, 9 are rotatable about lateral link shafts 6, 7 that are attached to bearing brackets formed at the front ends of the left and right sides of the vehicle body 5. The rear ends of the four left and right parallel links 8, 9 are pivotally attached by link shafts 36, 37 to the rear ends of the four left and right parallel links 8, 9, and the mowing deck 3 is raised and lowered, maintaining a position parallel to the ground to be mowed, via lift links 39, by the rotation of a lift arm 38 that is rotated by the expansion and contraction of an electric cylinder 50. At the highest height of the mowing deck 3, the upper surface of the ceiling of the mowing deck 3 is close to the bottom of the vehicle body 5, and is set to be at the upper limit of the mowing height. Furthermore, when the mowing deck 3 is lowered to its lowest height, the cutting height of the grass cut by the blade 1 rotating inside the mowing deck 3 is at its lowest position. Furthermore, guard chains 102 are attached to the vehicle body 5 and suspended from the front and rear of the mowing deck 3. The guard chains 102 are provided with a rubber plate on the mowing deck 3 side, and the chain is suspended on the outside so as to follow the rubber plate, effectively preventing stones and other objects from flying about that are forcefully ejected from the mowing deck 3 during mowing work.

[0013] The mowing deck 3 has a vertical blade shaft 2 rotatably mounted in the center, and the center of a blade stay 40, with the blade 1 disposed on the outer periphery, is attached to the lower end of this blade shaft 2. On the upper side of the mowing deck 3, a blade pulley 17 in the form of a V-pulley is attached to the upper end of the blade shaft 2, which engages with a mowing belt 19 made of a V-belt with a V-shaped cross section and guides its rotation.

[0014] A counter shaft 14 is rotatably erected above the mowing deck 3, just behind the blade shaft 2 and parallel to the blade shaft 2, and a V-pulley-type counter pulley 13 is provided on this counter shaft 14, with an upper counter pulley 13a at its upper end and a lower pulley 21 at its lower end. A V-belt-type mowing belt 19 is stretched between the lower pulley 21 of the counter shaft 14 and the blade pulley 17 of the front blade shaft 2, and power transmission from the counter shaft 14 to the blade shaft 2 can be switched on and off by tensioning and loosening a tension pulley 18 on the rotating outer periphery of the mowing belt 19. A clutch arm 41 of the tension pulley 18 is pivotally mounted on a pivot shaft 42 on the upper surface of the mowing deck 3 at the outer periphery of the lower pulley 21, and an operating wire 43 connected to this clutch arm 41 is connected to an operating arm 45 which is rotated about an arm shaft 46 by an electrically extended and retracted mowing clutch 20 and an electric cylinder 44 for braking the blade shaft 2, and the extension and retraction of this electric cylinder 44 engages and disengages the mowing clutch 20 by the tension pulley 18 (see Figures 4 and 5).

[0015] In addition, a brake arm 47 is rotatably mounted around an arm shaft 48 on the upper surface of the mowing deck 3 around the blade pulley 17. The brake arm 47 fits into and slides against the V-groove portion of the blade pulley 17 to brake the rotation of the blade shaft 2, and is connected to an operating arm 45, which is rotated around the arm shaft 46 by the electric cylinder 44, by an operating wire 49. By pushing and rotating the electric cylinder 44, the operating arm 45 can be rotated from the cut-off position b of the mowing clutch 20 to the on position a, pulling the wire 43 and tensioning the tension pulley 18 and clutch arm 41 of the mowing clutch 20 against the mowing belt 19, thereby placing the mowing clutch 20 in a transmission-on position. Also, at this time, when the operating arm 45 is rotated from the brake position f to the brake release position e, the operating wire 49 is pulled, causing the brake arm 47 to rotate around the arm shaft 48, and the brake shoe 47s, which is fitted and pressed against the V-pulley groove of the blade pulley 17, is moved away from the outside in the radial direction, releasing the braking force and allowing smooth transmission of cutting power by the cutting belt 19 from the counter shaft 14 to the blade shaft 12.

[0016] Furthermore, the mowing clutch 20 and brake arm 47, which are operated via the electric cylinder 44, operating arm 45, operating wires 43, 49, clutch arm 41, brake arm 47, etc., are operated by shortening the electric cylinder 44 and rotating the operating arm 45 from clutch-on position a to clutch-off position b, so that the mowing clutch 20 moves away from the mowing belt 19 via the operating wires 43, 49 to a transmission-released position, and the brake shoe 47s of the brake arm 47 slides into contact with the V-groove portion of the blade pulley 17 of the blade shaft 2, putting the blade shaft 2 into a braking state.

[0017] The engine base 15 has trapezoidal bracket arms 51 formed on the front and rear edges of its bottom to reinforce the support structure for the engine E and other components, and to facilitate setting a range of left and right rotation around a support member 16 on the center line L of the vehicle body 5. Support metals 53 are provided at the center of the width of horizontal beams 52 extending laterally from left to right at the front and rear of the vehicle body 5, and the support members 16 provided at the lower center ends of the bracket arms 51 are fitted and supported between the front and rear support metals 53, so that the engine base 15, which is normally positioned horizontally in the left-right direction, can rotate freely left and right over an appropriate angle θ range with respect to the vertical line Y of the vehicle body 5. An electric cylinder 54 provided between the vehicle body 5 and the engine base 15 extends and retracts to manually or automatically control the angle, so that the mounting position of the engine E on the inclined ground can always be maintained in the vertical position Y or at an angle within the allowable range of inclination of the engine E. Furthermore, a gas damper 103 is provided between the vehicle body 5 and the engine base 15, and pressure is constantly applied by the gas damper 103 in a direction that presses the electric cylinder 54, making it difficult for rattles to occur in the engine base 15 and other peripheral components. When the engine base 15 tilts, the gas damper also expands and contracts in accordance with the expansion and contraction of the electric cylinder 54, and the pressure is constantly applied, making it difficult for rattles or damage to occur in the components around the engine base 15.

[0018] An engine E is mounted on the front of the engine base 15, and a battery 24b for driving a motor M, a fuel tank 26, a generator 25, and the like are mounted on the rear of the engine base 15. The drive shaft 11 of the engine E protrudes vertically downward at the front of the engine base 15, and two pulleys with upper and lower V-shaped belt grooves are formed on the drive shaft 11. A drive belt 10 is passed between the lower drive pulley 12b and an upper counter pulley 13a of a counter pulley 13 at the rear of the mowing deck 3, and a tension pulley 60 is tensioned to constantly transmit rotation. An upper V-pulley 55 for driving the generator 25 is provided above the drive pulley 12, and a generator belt 58 is passed between the drive pulley 12 and a generator pulley 57 attached to a generator shaft 56 of the generator 25 mounted on the rear of the upper V-pulley 55, and a tension pulley 59 is tensioned to constantly transmit rotation.

[0019] An exhaust pipe 84 is attached to the bottom of the engine E. The exhaust pipe 84 is a cylindrical pipe, with one end connected to the engine E as an inlet and the other end connected to a muffler 88 as an exhaust port. Exhaust gas generated in the combustion chamber of the engine E is introduced into the exhaust pipe 84 from the inlet, flows through the exhaust pipe 84, and is released to the outside via the muffler 88 connected to the exhaust port. Note that, since the engine E in this embodiment is a two-cylinder engine having two cylinders, the exhaust pipe 84 is bifurcated, with two inlets and one exhaust port. Exhaust gas generated by burning a fuel-air mixture in the left combustion chamber of the engine E is introduced into the exhaust pipe 84 from an inlet on the left side of the exhaust pipe 84 located below the engine. The exhaust pipe 84 is configured so that exhaust gas flows horizontally to the right of the vehicle body 5. The exhaust gas introduced from the left inlet merges with the exhaust gas introduced from the right inlet and flows toward the right of the vehicle body 5. It is then introduced into the muffler 88 and discharged into the atmosphere from an exhaust port 96 at the top of the muffler 88 towards the right side of the vehicle body.

[0020] Furthermore, the engine E is mounted so that the exhaust pipe 84 is positioned forward of the engine E and further so that the exhaust pipe 84 is positioned forward of the front end of the engine base 15 in a plan view. As a result, even if grass clippings accumulate on the engine base 15, the exhaust pipe 84 does not overlap the engine mounting surface 67 of the engine base 15 in a plan view, preventing the grass clippings from coming into contact with the exhaust pipe 84. Furthermore, a front cover 89 is attached to the exhaust pipe 84, and the front cover 89 covers the front and top surfaces of the exhaust pipe 84. This prevents grass from coming into contact with the exhaust pipe 84 from the front or above when mowing while moving forward. Furthermore, the front cover 89 is open at the bottom, preventing grass clippings accumulated inside the front cover 89 from coming into contact with the exhaust pipe 84.

[0021] Additionally, a cover 85 is attached to the front end of the engine base 15 below the exhaust pipe 84. The cover 85 is positioned with an appropriate vertical gap to prevent grass clippings from getting caught in the gap between the cover 85 and the exhaust pipe 84. Furthermore, the cover 85 is configured with a downward slope toward the front. Therefore, even if grass clippings land on the top surface of the cover 85, they slide forward, preventing them from accumulating and contacting the exhaust pipe 84. The downward slope toward the front can be adjusted as needed to allow the grass clippings to slide off. Furthermore, the front end of the cover 85 protrudes forward beyond the front end of the mowing deck 3 and is provided across the left and right inlets of the exhaust pipe 84. As a result, even if a large amount of grass clippings accumulates on the mowing deck 3, the underside of the cover 85 holds down the grass clippings and prevents them from contacting the exhaust pipe 84. Furthermore, when the mowing deck 3 is set to its highest height and the engine base 15 tilts left or right during operation, the upper surface of the mowing deck 3 and the exhaust pipe 84 come close to each other. However, even in this case, the cover 85 prevents contact between the exhaust pipe 84 and the mowing deck 3, as described above. The cover 85 only needs to be provided in the area where the exhaust pipe 84 and the mowing deck 3 overlap in a plan view, and the presence or absence of the cover 85 outside of this area is not limited. Furthermore, when the mowing deck 3 descends, the mowing deck 3 rotates downward and toward the front due to the parallel links 8, 9 that are in a forwardly upwardly inclined configuration. Therefore, the cover 85 is configured so that its front end is positioned forward of the front end of the mowing deck 3, even when the mowing deck 3 is set to its lowest height.

[0022] Additionally, the cover 85 is provided above the cross beam 52. Here, the front end of the cover 85 may be configured to protrude further forward than the cross beam 52 at the front of the vehicle body 5 and the front end of the mowing deck 3 in a plan view. This makes it possible to prevent branches or grass stems from coming into contact with the exhaust pipe 84, even if they enter from the front of the vehicle body 5 and become trapped between the upper surface of the cross beam 52 at the front of the vehicle body 5 and the vehicle body 5 or the engine base 15. [Explanation of symbols]

[0023] 1. Grass cutting deck 5. Body 15 engine base 61 Abdomen 84 Exhaust pipe 85 Cover E-Engine

Claims

[Claim 1] A remote-controlled grass cutter comprising: a grass cutting deck (3) that can be raised and lowered in an abdominal section (61) that is approximately in the center of the front, rear, left, and right of the vehicle body; an engine base (15) that is supported so as to be able to rotate freely left and right above the grass cutting deck (3); an engine (E) is mounted on the front of the upper surface of the engine base (15) so that an exhaust pipe (84) of the engine (E) is located forward of the front end of the engine base (15); a cover (85) that slopes downwards toward the front is attached to the engine base (15) below the exhaust pipe (84) at a portion where the exhaust pipe (84) and the grass cutting deck (3) overlap in at least a plan view; and the front end position of the cover (85) protrudes forward of the grass cutting deck (3).

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