Grass mower, grass mower lifting structure, and grass mowing method

Abstract

To provide a lifting structure for a mowing machine having improved maintainability of a mowing part compared with a conventional machine having the mowing part on a machine body bottom surface, and to provide a mowing machine and a mowing method provided with the lifting structure.SOLUTION: The grass mower 1 includes a lower frame part 2 in which a void or an opening is formed in an inner region, traveling parts 3 arranged on both left and right sides of the lower frame part 2, an upper frame part 4 arranged above the lower frame part 2, and a connection mechanism part 5 which is arranged in front of or behind a machine body, pivotally attaches the upper frame part 4 and the lower frame part 2, and connects the upper frame part 4 liftably with a support shaft intersecting a traveling direction of the machine body as a rotation fulcrum. The mower is equipped with a mowing part 9 provided so as to mow with rotary mowing blades 91 and 92 positioned at a place becoming the lower part of the upper frame part 4 in the lowered state of the upper frame part 4, a power part 7 capable of driving the traveling part 3 and the mowing part 9 and a control part 8 capable of controlling the mowing part 9 and the power part 7.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to a grass cutter, a lifting structure for a grass cutter, and a grass cutting method, and more particularly to a grass cutter lifting structure that improves the ease of maintenance of the grass cutter unit compared to conventional grass cutters that have a grass cutter unit on the bottom of the machine body, and to a grass cutter and a grass cutting method that include the same. [Background technology]

[0002] Conventionally, mowers having a mowing section on the bottom of the machine body (hereinafter sometimes referred to as "conventional machines") have been manufactured and sold, and one such mower has been proposed by the present inventor, for example, as shown in Patent Document 1 listed below. The object of this mower is to provide a mower that has a relatively simple structure yet can be suitably used by remote control. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2022-120740 Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, many conventional machines with a mowing unit located on the bottom of the machine, including the mower shown in Patent Document 1, have a heavy machine body, and when performing maintenance on the mowing unit, it is necessary to have several people lift it, lift it using equipment such as an elevator or a hoist crane, or disassemble the machine.

[0005] For this reason, when mowing outdoors, vines, plastic string hidden in the vegetation, wire, or other fallen or installed objects (hereinafter referred to as "rotation obstructions") may become entangled in the rotary mower blade, preventing it from rotating, or when an emergency maintenance operation is required due to the need to replace a part of the rotary mower blade, the operator may have to go to the vehicle where the elevator or other equipment is located, which can result in reduced work efficiency. Needless to say, maintenance that requires disassembly of the machine can also result in reduced work efficiency.

[0006] The present invention was devised in consideration of the above points, and aims to provide a lifting structure for a grass cutter that improves the maintainability of the grass cutter section compared to conventional machines that have a grass cutter section on the bottom of the body, as well as a grass cutter and grass cutter method equipped with the same. [Means for solving the problem]

[0007] In order to achieve the above object, the brush cutter of the present invention comprises a lower frame section having a gap or opening formed in an inner region, running sections arranged on both the left and right sides of the lower frame section in the direction of travel of the machine body, an upper frame section arranged above the lower frame section, a connection mechanism section arranged in front or behind the direction of travel of the machine body, which axially attaches the upper frame section to the lower frame section and connects the upper frame section so that it can be raised and lowered around a support axis that intersects the direction of travel of the machine body as a pivot point, a grass cutting section attached to the upper frame section and arranged so that it can cut grass with a rotary grass cutting blade located below the upper frame section when the upper frame section is in a lowered state, a power section capable of driving at least the running section, and a control section capable of controlling the grass cutting section and the power section.

[0008] According to the brush cutter of the present invention, by being provided with the above-mentioned structure of each part, it is possible to perform the grass cutting work, and when maintenance of the grass cutting part, such as replacing the cutting blade, is required during the grass cutting work, the upper frame part can be raised to expose the grass cutting part and the maintenance work can be performed. The functions of each part that makes up the brush cutter are as follows.

[0009] The lower frame section serves as a mounting base for the running section and the upper frame section. The lower frame section can expose the rotary grass cutting blade downward through a gap or opening formed in the inner region when the upper frame section is in the lowered position. The running section is arranged as described above, allowing the machine to travel stably. The upper frame section serves as a mounting base for the grass cutting section.

[0010] The connecting mechanism has the above-mentioned structure, which allows the upper frame to be connected to the lower frame so that it can be raised and lowered. The upper frame is raised and lowered using the support shaft as a pivot point, so simply by lifting the upper frame, the mowing unit located on the bottom of the machine can be exposed with a small opening, making work easier and allowing the mowing unit to be exposed quickly, safely, and easily.

[0011] The control unit can control the mowing unit and the power unit. The term "control unit" is used to mean either mechanical control or electrical control. Furthermore, the mower may be a riding type or a push type, or it may be an unmanned type that can perform mowing work by remote control based on an operation signal received from outside the machine. The "operation signal" referred to here includes signals received by either a wireless system or a wired system.

[0012] The power unit is activated by a signal from the control unit and can drive at least the traveling unit. Examples of the power unit include prime movers such as a motor or an engine, and may also be combined with a gearbox or a transmission. The power unit may consist of not only one unit but also two or more units. The power unit may be connected to the mowing unit via power transmission means such as a belt, chain, or shaft, and may also drive the rotary mowing blade.

[0013] The mowing unit is operated by a control signal from the control unit, and when the upper frame unit is in the lowered state, the rotary mowing blade located below the upper frame unit rotates to perform mowing work. Note that the power to drive the mowing unit may be received from the power unit as described above, or may be received from a dedicated motor or the like.

[0014] As mentioned above, conventional mowers with the mowing unit located on the bottom are heavy, so when performing maintenance on the mowing unit, it is necessary for several people to lift it, or to lift it using equipment such as an elevator or hoist crane, or to disassemble it.

[0015] For this reason, when emergency maintenance is required during outdoor mowing work due to an incident such as a plastic string or other obstacle hidden in the vegetation becoming entangled in the rotary mower blade and preventing it from rotating, the operator must go back to the vehicle where the elevator or other equipment is located, which reduces work efficiency. Needless to say, maintenance that requires disassembly also reduces work efficiency.

[0016] In contrast, with the brush cutter of the present invention, the effects of the various parts described above make it easier to perform maintenance on the mowing section anywhere compared to conventional brush cutters, improving work efficiency. Even if emergency maintenance such as that described above is anticipated, it can be resolved with fewer personnel. Furthermore, since maintenance on the mowing section does not require work to be performed from below the machine by lifting or suspending it with an elevator or the like, accidents such as the machine falling due to improper fastening are unlikely to occur, contributing to ensuring the safety of the operator.

[0017] Furthermore, in the above-described brush cutter, the power shaft of the drive wheels or drive wheels provided on the traveling part and the support shaft of the connecting mechanism part may be a common shaft.

[0018] According to this type of brush cutter, the power shaft of the drive wheels, etc. and the support shaft of the connection mechanism are of a common structure, which reduces the number of components, thereby simplifying the body structure and making the body lighter, and also contributing to reducing manufacturing costs.

[0019] Furthermore, the above-mentioned brush cutter may further include a lifting / lowering assisting section disposed between the lower frame section and the upper frame section, which assists the lifting / lowering operation of the upper frame section and can be stopped at any position.

[0020] According to the brush cutter of this aspect, by providing the lifting assist unit with the above-described structure, it is possible to prevent accidents caused by the unintended descent of the upper frame unit when it is raised. Furthermore, according to the brush cutter of this aspect, the lifting assist unit can stop the lifting of the upper frame unit at any desired point, so the mowing unit provided on the bottom of the machine body can be exposed and fixed in position at an appropriate opening angle that makes it easy to work, further improving workability.

[0021] By the way, there are situations where lawn mowers are used on slopes where the body of the machine is inclined forward, backward, left and right. If the upper frame part is a lift-up type that does not have an opening adjustment function, the center of gravity will be too high, which may cause the machine to lose balance and tip over.

[0022] However, with this type of brush cutter, the lifting position of the upper frame section can be stopped at an appropriate opening, so the lifting of the upper frame section can be adjusted (stopped at an appropriate opening) so that the center of gravity does not become too high and the machine does not lose balance and tip over, thereby reducing the occurrence of accidents such as damage to the machine due to tipping over or injuries to workers who are caught in the machine tipping over, and also contributing to ensuring work safety.

[0023] In addition, in order to achieve the above-mentioned object, the lifting structure for a grass cutter of the present invention is a structure applicable to a grass cutter which has a lower frame part having a running part and a gap or opening formed in an inner region, and an upper frame part arranged above the lower frame part, and is equipped with a connection mechanism part which is arranged in front or behind the traveling direction of the machine body and which axially attaches the upper frame part to the lower frame part and connects the upper frame part so that it can be raised and lowered using a support axis which intersects with the traveling direction of the machine body as a pivot point, and a grass cutting part which is attached to the upper frame part and is arranged so that it can cut grass with a rotary grass cutting blade which is located below the upper frame part when the upper frame part is in a lowered state.

[0024] According to the lifting structure for a grass cutter of the present invention, by being equipped with the above-mentioned component structures, when maintenance of the grass cutting part, such as replacing the cutting blade, is required during grass cutting work, the upper frame part can be raised to expose the grass cutting part and the maintenance work can be performed. Note that this lifting structure for a grass cutter can be applied not only to remote-controlled grass cutters, but also to push-type and riding-type grass cutters. The functions of the components that make up this grass cutter are as follows.

[0025] The connecting mechanism has the above-mentioned structure, which allows the upper frame to be connected to the lower frame so that it can be raised and lowered. The upper frame is raised and lowered using the support shaft as a pivot point, so simply by lifting the upper frame, the mowing unit located on the bottom of the machine can be exposed with a small opening, making work easier and allowing the mowing unit to be exposed quickly, safely, and easily.

[0026] When the upper frame section is in the lowered state, the rotary mower blade located below the upper frame section rotates to perform grass cutting work. The mower section is operated by a signal from the control section, for example, and the power to drive the mower section may be received from the power section as described above, or may be received from a dedicated motor or the like.

[0027] As mentioned above, with conventional mowers (conventional models) that have the mowing unit located on the bottom, for example, when emergency maintenance is required while mowing outdoors, the operator must return to the vehicle where the elevator or other equipment is located, which is time-consuming and reduces work efficiency.

[0028] In contrast, with the lifting structure for a grass cutter of the present invention, the effects of the various components described above make it easier to perform maintenance on the grass cutting section of a grass cutter to which this structure is applied than on conventional grass cutters, regardless of the work location, thereby improving work efficiency. Furthermore, even if emergency maintenance such as that described above is anticipated, a grass cutter to which this lifting structure for a grass cutter is applied can be resolved with fewer personnel. Furthermore, when performing maintenance on the grass cutting section, there is no need to lift or hang the machine from below using an elevator or the like, so accidents such as the machine falling due to improper fastening are less likely to occur, and this also contributes to ensuring the safety of the worker.

[0029] In order to achieve the above object, the mowing method of the present invention uses a mower comprising a lower frame section, a travel section, an upper frame section, a connection mechanism section that pivots and connects the upper frame section and the lower frame section so that they can be raised and lowered, a mowing section that is attached to the upper frame section and has a rotary mowing blade, a power section, and a control section, wherein the control section controls the power section, and the power section drives travel sections that are arranged on both the left and right sides of the lower frame section in the direction of travel of the machine body, causing the mower to travel to a working area using the travel sections, and the control section controls the mowing section, and the mowing section is located below the upper frame section when the upper frame section is in a lowered state, and is formed in an inner area of ​​the lower frame section when in the lowered state. The grass cutting work is performed with the rotary grass cutting blade exposed below the body of the machine through the gap or opening, and if, during the grass cutting work, an obstacle that hinders the rotation of the rotary grass cutting blade becomes entangled with the rotary grass cutting blade, making it unable to rotate, or if an event occurs in which a part of the rotary grass cutting blade needs to be replaced, the upper frame part is raised via a connection mechanism part that is arranged in front or behind the traveling direction of the body of the grass cutting machine, axially attaches the upper frame part to the lower frame part, and connects the upper frame part so that it can be raised and lowered around a support axis that intersects the traveling direction of the body of the grass cutting machine as a rotation fulcrum, thereby exposing the grass cutting part, and maintenance work can be performed to remove the obstacle to rotation or replace a part of the rotary grass cutting blade.

[0030] According to the grass-cutting method of the present invention, by incorporating the above-mentioned steps, grass-cutting work can be performed by remote control from outside the machine, and when maintenance of the grass-cutting part, such as replacing the cutting blade, is required during grass-cutting work, the upper frame part can be raised to expose the grass-cutting part and perform the maintenance work.

[0031] In particular, because the connecting mechanism has the above-mentioned structure, the upper frame can be connected to the lower frame so that it can be raised and lowered.The upper frame is raised and lowered using the support shaft described above as a pivot point, so simply by lifting the upper frame, the mowing unit located on the bottom of the machine can be exposed with a small opening, making work easier and allowing the mowing unit to be exposed quickly, safely, and easily.

[0032] In other words, the mowing method of the present invention makes it easier to perform maintenance on the mowing unit in any work location compared to conventional mowers, improving work efficiency. Even if emergency maintenance such as that described above is anticipated, it can be resolved with fewer personnel. Furthermore, even when performing maintenance on the mowing unit, there is no need to lift or hang the machine from below using an elevator or the like, so accidents such as the machine falling due to improper fastening are unlikely to occur, contributing to ensuring the safety of workers.

[0033] In the mowing method of the present invention, as with the above-mentioned mower, the term "control unit" is used to mean either mechanical control or electrical control. Furthermore, the mower may be a riding or push type, or an unmanned type that can perform mowing work by remote control based on an operation signal received from outside the machine. The "operation signal" here includes signals received by either a wireless or wired system.

[0034] The "power unit" is primarily a prime mover such as a motor or engine, and may further be a combination of a gearbox, transmission, etc., and may consist of not just one unit but two or more units. The "power unit" may also be connected to the grass cutting unit via a power transmission means such as a belt, chain, or shaft, and may also drive the rotary grass cutting blade. Furthermore, the power that drives the "grass cutting unit" may be received from the power unit as described above, or may be received from a dedicated motor, etc. [Effects of the Invention]

[0035] According to the lifting structure for a mower, and the mower and mowing method equipped with the same of the present invention, the maintenance of the mowing unit is improved compared to conventional machines that have the mowing unit on the bottom of the machine body. [Brief explanation of the drawings]

[0036] [Figure 1] 1 is a perspective view of the brush cutter according to the present invention, viewed from the upper left, with the upper frame portion lowered. FIG. [Figure 2] 2 is a perspective view of the mower in FIG. 1 as viewed from below on the left, with the upper frame portion lowered. FIG. [Figure 3] 2 is a front view of the mower in FIG. 1 with an upper frame portion lowered. FIG. [Figure 4] 2 is a front view of the mower in FIG. 1, showing a state in which an upper frame portion is raised. [Figure 5] 2 is an explanatory diagram of the state in which the mower in FIG. 1 is used, showing the normal machine body position (with the upper frame portion lowered) during mowing work. FIG. [Figure 6] 2 is an explanatory diagram of the state in which the mower in FIG. 1 is used, showing the machine body posture for maintenance work (state in which the upper frame portion is raised); FIG. DETAILED DESCRIPTION OF THE INVENTION

[0037] An embodiment of the present invention will be described in more detail with reference to Figures 1 to 6. Note that the symbols associated with the arrows shown in Figures 1 to 6 indicate directions for the purpose of explanation, and with reference to the direction of the brush cutter shown in Figure 1 as the reference, the symbol F means "forward," the symbol B means "rearward," the symbol R means "rightward," the symbol L means "leftward," the symbol U means "upward," and the symbol D means "downward." Furthermore, the symbols in each drawing are assigned within the scope of reducing complexity and facilitating understanding, and in some cases, when multiple equivalent parts are assigned the same symbol, only some of the parts may be assigned the same symbol.

[0038] [Grass cutter 1] The grass cutter 1 will be described with reference to Figures 1 to 4. The grass cutter 1 is remotely operated by an operator wirelessly using a controller (not shown). The grass cutter 1 comprises a lower frame section 2, a travel section 3, an upper frame section 4, a connection mechanism section 5, a lifting and lowering auxiliary section 6, a power section 7, a control section 8, and a grass cutting section 9 (see Figures 1 to 4). Note that in the grass cutter 1, the structure formed by the combination of the lower frame section 2, the upper frame section 4, the connection mechanism section 5, the lifting and lowering auxiliary section 6, and the grass cutting section 9 corresponds to the "lifting structure for a grass cutter" described above. Each section will be described in detail below.

[0039] (Lower frame part 2) The lower frame 2 constitutes the lower part of the brush cutter 1. The lower frame 2 has a U-shape in plan view (in other words, a shape that is open only in the front direction) with the left and right sides and rear direction of the machine body connected together, and is open at the top and bottom. A skirt portion 21 is provided in the front direction (opening portion) of the lower frame 2, and a skirt portion 22 is provided in the rear direction of the lower frame 2.

[0040] Skirt portion 21 is provided to protrude downwardly toward the front of the vehicle, has a width approximately equal to that of lower frame portion 2, and is provided so that its tip is higher than the underside of the crawler belt. Skirt portion 22 is provided to protrude downwardly toward the rear of the vehicle, has a width approximately equal to that of lower frame portion 2, and is provided so that its tip is higher than the underside of the crawler belt (see Figures 3 and 4). Skirt portions 21 and 22 are made of a flexible material and are curtain-shaped members with multiple slits provided vertically.

[0041] (Running section 3) The running units 3 are disposed on both the left and right sides of the lower frame 2 in the direction of travel of the machine body, and in this embodiment have a symmetrical track-type running structure. Note that the running unit 3 will be described based on the illustration of the left side of the machine body, but the running unit 3 disposed on the right side of the machine body also has a symmetrical structure.

[0042] The running unit 3 has four rollers 31 arranged on the ground side, an idler wheel (also called a "guide wheel") 32 arranged on the front side of the body and above the rollers 31, a drive wheel 33 arranged on the rear side of the body and above the rollers 31, and a track 34 wrapped around the four rollers 31, the idler wheel 32 and the drive wheel 33.

[0043] The drive wheel 33 is connected to the rotary shaft of a second motor (described later) as a power shaft 331 (axle). The second motor is driven by electric power supplied directly from a first motor (described later) or by electric power stored in a battery.

[0044] (Upper frame part 4) The upper frame section 4 is disposed above the lower frame section 2. The upper frame section 4 has a structure in which a frame section 42, which is a tubular frame, is disposed above a bottom plate section 41. The upper frame section 4 is provided with a mowing section 7, a power section 8, and a control section 9.

[0045] In the inner region of the upper frame portion 4, a first cowl 431 is attached to cover the power unit 8, and a second cowl 432 is attached to cover the control unit 9. The first cowl 431 and the second cowl 432 are formed from a material having a predetermined rigidity and waterproof properties, and are provided with a structure that allows them to be easily attached and detached.

[0046] (Connection mechanism part 5) The connection mechanism 5 is disposed at a position at the rear of the machine body in FIG. 1, and has a structure in which the upper frame part 4 and the lower frame part 2 are axially connected by a support shaft 51. The connection mechanism 5 connects the upper frame part 4 so that it can be raised and lowered, with the support shaft 51, which intersects with the traveling direction of the machine body, as a pivot point. The support shaft 51 and the power shaft 331 of the drive wheel 33 are a common shaft.

[0047] (Lifting auxiliary part 6) The lifting assistance unit 6 is an air damper arranged between the lower frame unit 2 and the upper frame unit 4, and corresponds to the aforementioned "unit that assists the lifting and lowering movement of the upper frame unit 4 and can stop it at any position."

[0048] (Power part 7) The power unit 7 is disposed on the front side of the aircraft body and is covered with a first cowl 431. The power unit 7 has an engine, a first motor, a second motor, a third motor, a battery, a first pulley, a second pulley, a third pulley, a fourth pulley, a first belt, a second belt, a first clutch, and a second clutch. Note that the engine and other components are not shown in the drawings.

[0049] The engine has a recoil starter-type engine body, a rotating shaft (first shaft) that can transmit power to the outside, and a connected fuel tank. The rotating shaft (first shaft) protrudes to the right of the aircraft, and a first pulley is attached to the protruding part (each part is not shown).

[0050] The first motor is located to the side of the engine (in the width direction of the aircraft) and has a rotating shaft (second shaft) that can transmit power to the outside. The rotating shaft (second shaft) protrudes to the right of the aircraft, and a second pulley and a third pulley are provided on the protruding part (each part is not shown).

[0051] The second motor is attached to the left side of the vehicle body, is connected to both the first motor and the battery, and is driven by the supplied power. The second motor's rotation shaft is connected to the axle (the aforementioned power shaft 331) of the left drive wheel 33 (each part is not shown). In other words, the second motor corresponds to the aforementioned "power part capable of driving the traveling part."

[0052] The third motor is attached to the right side of the vehicle body, is connected to both the first motor and the battery, and is driven by the supplied power. The third motor's rotation shaft is connected to the axle (the aforementioned power shaft 331) of the right drive wheel 33 (each part is not shown). In other words, the third motor corresponds to the aforementioned "power unit capable of driving the traveling unit."

[0053] The battery is electrically connected to the first motor, second motor, third motor, and control unit 8 including a signal transmitting / receiving unit, and is provided so as to be able to supply power to each of them (each unit is not shown).

[0054] The first belt is wound around a first pulley and a second pulley, and is provided so as to be capable of transmitting power between the first pulley and the second pulley. A first clutch (disconnecting unit) is disposed near the first belt, and is provided so as to be capable of disconnecting power transmission between the engine 1 and the first motor (each unit is not shown).

[0055] The second belt is wound around a third pulley and a fourth pulley, and is provided so as to be able to transmit power between the third and fourth pulleys. A second clutch is disposed near the second belt, and is provided so as to be able to interrupt the transmission of power between the first motor and the mowing unit 9 (each part is not shown).

[0056] (Control unit 8) The control unit 8 is disposed on the rear side of the machine body and is covered with a second cowl 432. The control unit 8 is capable of controlling the power unit 8 and the mowing unit 9 based on operation signals received from outside the machine, and includes a signal transmitting / receiving unit and the like (each unit is not shown).

[0057] The signal transmitting / receiving unit is provided near the second cowl 432. The signal transmitting / receiving unit is provided so as to be able to transmit operation signals received from outside the aircraft (such as a controller) to each part constituting the control unit 8, and is also provided so as to be able to transmit signals transmitted from each part constituting the control unit 8 (for example, the state of each part of the aircraft) to outside the aircraft (such as a controller or a mobile terminal) (not shown).

[0058] Each part of the control unit 8 is provided in an inner box (reference numerals omitted) and is electrically connected to the signal transmitting / receiving unit. The control unit 8 is composed of a transmitting / receiving device for the signal transmitting / receiving unit, a calculation unit, a control unit, an input device, an output device, a main memory device, a load determination unit, etc. (each part is not shown). The load determination unit has the function of comparing the engine speed measured by the above-mentioned speed measuring device with preset speed data to determine whether or not the current load is high, and the function of transmitting a signal notifying the control unit of the high load state when it determines that the current load is high, and the control unit receiving the signal increases the output of the first motor.

[0059] (Mowing Department 7) The grass cutting unit 7 has a gear box having a rotating shaft (third shaft) connected to the fourth pulley and arranged on the side, and two rotating shafts (fourth shaft and fifth shaft) arranged below, and two rotary grass cutting blades (rotary grass cutting blades 91 and 92).

[0060] The rotary grass cutting blade 91 is disposed at a position on the front right side of the bottom plate portion 41. The rotary grass cutting blade 92 is disposed at a position on the rear and left side of the rotary grass cutting blade 91 on the bottom plate portion 41. The rotary grass cutting blades 91 and 92 are disposed in an area that becomes the inside of the lower frame portion 2 when the upper frame portion 4 is in the lowered state.

[0061] In other words, the grass cutting unit 7 is "attached to the upper frame unit 4 and is configured to be able to cut grass using rotary grass cutting blades 91 and 92 that are located below the upper frame unit 4 when the upper frame unit 4 is in a lowered state."

[0062] The gearbox is provided in such a way that gears provided at the ends of the horizontal rotating shafts mesh with gears provided on the vertical rotating shafts (fourth shaft and fifth shaft) within the box to enable power transmission (not shown). Note that, as the gears, for example, bevel gears can be used, but other known techniques are not excluded.

[0063] The downward rotating shafts (fourth shaft and fifth shaft) of the gearbox pass through through holes (not shown) provided in the bottom plate portion 41 and protrude downward from the body of the machine, with a rotary grass cutting blade 91 attached to the tip of the protruding fourth shaft and a rotary grass cutting blade 92 attached to the tip of the protruding fifth shaft.

[0064] The rotary grass-cutting blades 91 and 92 each have a structure including cover portions 911 and 921, base portions 912 and 922, and cutting blades 913 and 923 (see FIGS. 2 to 4).

[0065] The cover portions 911 and 921 are cylindrical with a bottom that tapers in diameter from top to bottom, and are disposed between the bottom plate portion 41 and the base portions 912 and 922. The cover portion 911 contains the fourth shaft, and the fourth shaft is rotatably disposed inside the cover portion 911. The cover portion 921 contains the fifth shaft, and the fifth shaft is rotatably disposed inside the cover portion 911.

[0066] The base 912 is an oval plate, and the fourth shaft described above is inserted at the intersection of its major and minor axes. The base 922 is an oval plate, and the fifth shaft described above is inserted at the intersection of its major and minor axes.

[0067] The cutting blade 913 is detachably attached to two opposing locations on an edge that is an extension of the long axis of the base 912. The cutting blade 913 is composed of a pair of upper and lower blades that sandwich the plate surface of the base 912. The cutting blade 923 is detachably attached to two opposing locations on an edge that is an extension of the long axis of the base 922. The cutting blade 923 is composed of a pair of upper and lower blades that sandwich the plate surface of the base 922 (see FIGS. 2 to 4).

[0068] The term "substantially the same" in the description of the skirt portions 21 and 22 is used to mean not only a state in which the width is completely the same as the width of the lower frame portion 2, but also a state in which the width is slightly larger or slightly smaller than the width of the lower frame portion 2. The aforementioned "slightly" preferably means that the range of difference is within +10% to -10% of the width of the lower frame portion. If the width of the skirt portions is 10% or more shorter than the width of the lower frame portion, more grass and other objects to be cut will pass through the gap, resulting in uneven cutting, which is undesirable. On the other hand, if the width of the skirt portions is 10% or more longer, it is undesirable because it will increase unnecessary resistance when the machine moves forward.

[0069] In this embodiment, the drive wheel power shaft and the support shaft of the connection mechanism are common, but this is not limited to this, and for example, the drive wheel power shaft and the support shaft of the connection mechanism may be separate shafts, in which case it becomes easier to change the location of the connection mechanism (machine design) as appropriate depending on the position of the grass cutting unit and the size and shape of the machine. Also, in this embodiment, the support shaft of the connection mechanism is provided at the rear of the machine, but this is not limited to this, and for example, it may be provided at the front of the machine taking into consideration the location of the grass cutting unit and its maintainability, etc.

[0070] In this embodiment, the lower frame portion 2 has the shape described above, but is not limited to this. For example, if the structure allows the front of the machine to take in grass or other work objects, part of the frame may also be present at the front (in which case the shape of the lower frame will be square when viewed from above). Furthermore, the shape of the lower frame portion is not limited to the shape described above as long as it is a shape that allows the grass-cutting portion to be exposed downward when the upper frame portion is lowered (a shape with openings above and below the lower frame portion). For example, the inner area surrounded by the frame may be an empty space, or may be square or I-shaped when viewed from above, or H-shaped when viewed from above, or may even be plate-shaped or box-shaped with openings formed in the inner area of ​​the side.

[0071] In this embodiment, the upper frame portion 4 is a tubular frame, but is not limited to this, and various types of frames such as a box type can be appropriately adopted.

[0072] In this embodiment, the brush cutter 1 is remotely controlled wirelessly by a controller, but this is not limited to this and, as mentioned above, it may be wired, or may be operated by a mobile information terminal such as a smartphone or tablet terminal or a personal computer used by a worker or manager, or may even be operated by automatic or autonomous control using a computer program.

[0073] In this embodiment, the brush cutter 1 is provided with skirt portions 21 and 22, but this is not limited to this, and for example, embodiments in which the shapes of the skirt portions 21 and 22 are different or in which the skirt portions 21 and 22 are not provided are not excluded.

[0074] In this embodiment, the traveling unit 3 has a crawler type traveling structure, but is not limited to this, and may have a structure having independent traveling wheels, such as four or six wheels.

[0075] In this embodiment, the lift assisting part 6 is an air damper, but is not limited to this and may be, for example, a hydraulic damper. The lift assisting part is not particularly limited as long as it "assists the lifting and lowering operation of the upper frame part and can be stopped at any position," and may be a mechanism using various springs or a non-extensible member such as a stay or support clamp.

[0076] In this embodiment, the power unit 7 has the above-described configuration, but is not limited to this and various modifications are possible. For example, in this embodiment, the power unit 7 employs a belt as a power transmission means, but this does not exclude the possibility of replacing it with a chain. Also, although the second pulley and the third pulley are described as separate components, they may be integrated into one structure. Furthermore, while the left and right drive wheels are each driven by a separate motor (second motor and third motor), this is not limited to this configuration and, for example, each drive wheel may be driven using a pulley or drive shaft. In this case, the battery may be electrically connected to the first motor, the signal transmission / reception unit, and the control unit and be capable of supplying power to each of them.

[0077] In this embodiment, the mowing unit 9 has the above-described configuration, but is not limited to this and can be modified as appropriate. For example, a worm gear or belt drive can be used as the power transmission mechanism between the horizontal rotation shaft and the vertical rotation shaft in the gearbox. The mowing unit 9 can also be configured without a cover, with a different base shape such as a square, with different numbers or positions of cutting blades arranged on the rotary mowing blade 91, or with cutting blades that are not arranged in pairs in the vertical direction.

[0078] [Operation of the grass cutter 1 and grass cutting method using it] The function and effect of each part of the mower 1 and a method for mowing using the mower 1 will be described with reference to FIGS.

[0079] <Start-up process> Use the starter motor to start the engine and start the lawnmower 1.

[0080] The brush cutter 1 can also be started by a signal from the controller. More specifically, starting the first motor rotates the second pulley, and power is transmitted to the first pulley via the first belt wound around the second pulley. The rotating shaft on which the first pulley is mounted is the engine crankshaft, and as this rotates (similar to pushing the engine), the engine starts. In other words, even an engine without a starter can be started in the same way as one with a starter. When the battery is completely discharged, the engine can also be started by pulling the recoil starter.

[0081] <Power generation and storage process> During normal operation of the brush cutter 1 with the engine started, the first pulley rotates using engine power, which in turn rotates the second pulley via the first belt wound around the first pulley, driving the first motor. In other words, during normal operation of the brush cutter 1, the first motor is driven by engine power to generate electricity constantly, and the generated electricity is stored in the battery. The electricity stored in the battery is supplied to various components, such as the first motor, second motor, third motor, clutch motors that operate the first and second clutches, a fuel shortage detection unit, a signal transmission / reception unit, and the like, and serves as a power source for the next engine start and machine operation (not shown).

[0082] <Moving process> Once started, the brush cutter 1 receives a signal from the controller (i.e., a signal from outside the machine) using the signal transmitter / receiver unit and transmits it to the control unit 8, which then drives the power unit 7 and running unit 3 under the control of the control unit 8, allowing the machine to move to a designated position, such as a work area with overgrown vegetation.

[0083] By having the first cowl 431 and second cowl 432 of the above-described structure, the brush cutter 1 can protect the power unit 7 and control unit 8 from causes of malfunction such as being covered with rain or mud, or being caught up in debris such as cut vegetation and its fragments, during movement, standby, operation, or storage.

[0084] The running unit 3 has a track-type running structure, which provides good running performance on rough roads and uneven terrain, and also provides good stability when working on slopes. In addition, because the drive wheels 33 are powered by motors (the second motor and the third motor), a complex mechanical structure is not required, allowing the machine body to have a relatively simple structure. Furthermore, when changing direction, the running unit 3 can be quickly turned on the spot by simply rotating the second motor and the third motor in the opposite direction to move each track 34 in the opposite direction, resulting in good maneuverability and maneuverability.

[0085] When the fuel runs out, the first clutch cuts off the transmission of power between the engine and the first motor, and the first, second, and third motors, which use power from the battery, can drive the traveling part 3. As a result, even if the engine stops due to running out of fuel in a location far from the operator, the operation can be switched to traveling using the power stored in the battery, and the brush cutter 1 can be returned to the operator without the operator having to go and retrieve the machine.

[0086] In addition, by activating the first clutch when the engine stops due to running out of fuel, it is possible to prevent damage to the internal mechanism, the rotating shaft (first shaft) and the first pulley, which may be caused by forcing the engine to run when it has run out of fuel using the power transmitted to the rotating shaft (first shaft).

[0087] <Grass cutting process> The mowing process will be described with reference to Figures 1 to 6 (particularly Figures 5 and 6). When the mower 1 is driven to a work area, the skirt portion 21 located at the front can push down the objects to be mowed W, such as grass and newly sprouted buds, by bending them in approximately the same direction (towards the direction in which the machine body travels).

[0088] At this time, the objects to be cut W are bent at a uniform height near the base due to the gap between the tip of the skirt portion 21 and the ground. As a result, when the objects to be cut W are subsequently cut by the mowing unit 9, the direction in which the objects to be cut W fall and the cutting height are approximately the same, making it less likely that uneven cutting will occur in the horizontal direction of the work area and less likely that the objects to be cut will become uneven in the height direction after cutting (in other words, it is easier to make the cutting heights of the objects to be cut W uniform after cutting), which improves work efficiency and contributes to improving the appearance of the work area after work (see the height of weeds, etc. on the right side of Figure 5).

[0089] In addition, the skirt portion 22 has the same effect as the skirt portion 21 when the brush cutter 1 is driven in reverse or in a turn in the work area, making it less likely that the object to be cut W will be cut unevenly or that the cutting height of the object to be cut W will be uneven after cutting, thereby improving work efficiency and contributing to improving the appearance of the work area after work.

[0090] The grass cutter 1 performs grass cutting work using rotary grass cutting blades 91 and 92 of the grass cutting unit 9 that rotates below the machine body. In the grass cutting unit 9, engine power is transmitted via a third pulley, a second belt, a fourth pulley, and a gear box, causing the base unit 922 to rotate. As a result, the cutting blade 923 attached to the base unit 922 cuts the object W to be cut.

[0091] When the brush cutter 1 is moving toward the work site, the second clutch is activated in the disengagement direction to prevent the rotary brush cutter blades 91 and 92 from spinning freely. Then, when the brush cutter 1 approaches or reaches the work site, the second clutch is activated in the engagement direction to enable power transmission (the clutch is engaged), and the rotary brush cutter blades 91 and 92 are rotated.

[0092] The rotating grass cutting blades 91 and 92, which make up the grass cutting unit 9, are arranged in positions on the bottom plate portion 41 where they are not aligned in the front-to-back or left-to-right direction of the machine body, so they do not interfere with each other and cut the objects W to be cut in different positions, which makes it less likely that uneven cutting will occur in the horizontal direction of the work area.

[0093] When the rotary grass cutting blades 91, 92 rotate, an event may occur in which the cutting object W1 before or after cutting becomes wrapped and tangled between the cover part 243 and the base part 243. When such an event occurs, the grass cutting machine 1 has a mechanism that predicts the motor rotation speed from the generated voltage and detects the load, and the load determination part compares the measured engine rotation speed with preset rotation speed data to determine whether or not the current load is high.

[0094] When an overload condition occurs due to reasons such as a large amount of harvesting material W, the system determines that the load is high and sends a signal to the control device in the control unit to notify of the high load condition. The control device then receives the signal and increases the output of the first motor (in other words, power assistance is provided by the first motor).

[0095] In other words, there is no need to approach the brush cutter 1 operating at a distance to check whether it is overloaded, improving the workability and convenience of the machine when remotely operated. Furthermore, even if the power unit 7 suddenly stops due to an object to be cut W getting caught in the rotary brush cutter blades 91, 92, the power unit 7 is a combination of a pulley and belt, so it can absorb the impact and reduce the possibility of breakdown.

[0096] Furthermore, there may be objects in the work area that hinder rotation, such as vinyl strings, which can become entangled in the rotary grass cutting blades 91 and 92, preventing them from rotating (see Figure 5), and emergency maintenance may be required.

[0097] However, with the grass cutter 1, even when maintenance of the grass cutting unit 9 becomes necessary, as shown in Figure 6, the grass cutter is provided with a lifting structure that can easily, safely and quickly expose the grass cutting unit 9 by simply raising the upper frame unit 4 connected via the connection mechanism unit 6, which has the structure described above, making it easy to perform maintenance work such as removing the string-like object S.

[0098] In other words, with the brush cutter 1, maintenance of the mowing unit 9 can be performed more easily in any work location than with conventional brush cutters, and even when emergency maintenance is required, there is no need to go back to the vehicle where the elevator or other equipment is located, improving work efficiency. Also, even if the need for emergency maintenance as described above is anticipated, it can be resolved with fewer personnel, which means that the number of personnel engaged in mowing work can be reduced.

[0099] By providing the lifting assist unit 6, the brush cutter 1 can prevent accidents caused by the unintended descent of the upper frame unit 4 when the upper frame unit 4 is raised. Furthermore, the lifting assist unit 6 can stop the rise of the upper frame unit 4 at any point, so the brush cutter 9 on the bottom of the machine can be exposed and fixed in position at an appropriate opening angle that makes it easy to work, further improving workability.

[0100] In addition, the lifting assistance unit 6 can stop the lifting position of the upper frame unit 4 at an appropriate opening, so that the lifting of the upper frame unit 4 can be adjusted (stopped at an appropriate opening) so that the center of gravity does not become too high and the machine does not lose balance and tip over, thereby preventing accidents such as damage to the machine due to tipping over or injuries to workers caught in the machine tipping over, and contributing to ensuring work safety.

[0101] Furthermore, even if the engine of the lawnmower 1 has stopped due to running out of fuel, if there is enough remaining power in the battery to allow the lawnmower 1 to return home, the power transmission between the engine and the first motor can be cut off by the first clutch, while the power transmission between the first motor and the gearbox can be connected, allowing the lawnmower 1 to continue mowing to a certain extent before returning home.

[0102] Furthermore, the brush cutter 1 has a structure in which the power shaft 331 of the drive wheel 33 and the support shaft 51 of the connection mechanism part 5 are common, which reduces the number of components, thereby simplifying the machine structure and reducing the weight of the machine, and also contributing to reducing manufacturing costs.

[0103] Furthermore, even during normal maintenance of the grass cutting unit 9 of the grass cutter 1, there is no need to lift or hang the machine from below, so accidents such as the machine falling due to improper fixing are unlikely to occur, which also contributes to ensuring the safety of the worker.

[0104] Incidentally, some conventional wireless or riding brush cutters have a mowing unit that protrudes from the front of the machine body, but these have a mechanical problem in that the machine body is long in the front-to-rear direction, and transporting them to the work site requires either a truck with a long loading platform or the machine body and mowing unit to be disassembled for transport. Furthermore, brush cutters with long bodies in the front-to-rear direction often have poor stability when moving up slopes with the machine body in an angled position during operation.

[0105] However, the grass cutter 1 has the grass cutting unit 9 located below the machine body, and the length of the machine body in the front-to-rear direction is shorter than the conventional grass cutter described above, so a truck with a long loading platform is not required, and on-site assembly work is not required. Furthermore, because the length of the machine body in the front-to-rear direction is shorter than the conventional grass cutter described above, the grass cutter 1 has good stability when traveling on slopes.

[0106] That is, the mowing method in this embodiment uses the mower 1 equipped with the above-described parts, (a) A normal grass cutting process in which the control unit 8 controls the power unit 7 based on an operation signal received from outside the machine, the power unit 7 drives the traveling unit 3 to cause the machine to travel to the work area, the control unit 8 controls the grass cutting unit 9 based on an operation signal received from outside the machine, and grass cutting work is performed using the rotary grass cutting blades 91 and 92 of the grass cutting unit 9 located at a position below the machine body when the upper frame unit 4 is in a lowered state. (b) a maintenance process in which, when a string-like object S (rotation obstruction object) that obstructs the rotation of the rotary grass cutting blades 91 and 92 becomes entangled and unable to rotate during grass cutting work, the upper frame part 4 is raised via the connecting mechanism part 5 to expose the grass cutting part 9, and the string-like object S (rotation obstruction object) is removed; It is equipped with the following.

[0107] In this way, the operation of the grass cutter 1 and the grass cutting method using it achieve the effects based on the configuration described above, and the maintenance of the grass cutting unit 9 is improved compared to conventional machines that have a grass cutting unit on the bottom of the body.

[0108] The terms and expressions used in the present specification and claims are merely descriptive and not limiting, and are not intended to exclude terms or expressions equivalent to the features described in the present specification and claims or portions thereof. It goes without saying that various modifications are possible within the scope of the technical concept of the present invention. Furthermore, the terms "first," "second," etc., do not imply rank or importance, but are used to distinguish one element from another. [Explanation of symbols]

[0109] 1. Lawnmower 2 Lower frame part 21 Skirt Club 22 Skirt Club 3 Running part 31 Wheel 32 Idler 33 Sprocket 331 Power shaft 34 Tracks 4 Upper frame section 41 Bottom plate part 42 Frame part 431 First Cowl 432 Second Cowl 5 Connection mechanism 51 Support shaft 6 Lifting assistance unit 7 Power section 8 Control Unit 9 Grass cutting department 91 Rotary grass cutting blade 911 Cover 912 base 913 cutting blade 92 Rotary grass cutting blade 921 Cover part 922 base 923 cutting blade W Weed S-shaped object

Claims

1. a lower frame portion having an inner region formed with a void or opening; Running sections are provided on both the left and right sides of the lower frame section in the direction of travel of the aircraft; an upper frame portion disposed above the lower frame portion; a connection mechanism portion disposed at the front or rear of the vehicle body in the traveling direction, which axially connects the upper frame portion and the lower frame portion, and which connects the upper frame portion so that the upper frame portion can be raised and lowered around a support shaft that intersects with the traveling direction of the vehicle body as a rotation fulcrum; a grass cutting unit attached to the upper frame portion and capable of cutting grass with a rotary grass cutting blade located below the upper frame portion when the upper frame portion is in a lowered state; a power unit capable of driving at least the traveling unit; a control unit capable of controlling the mowing unit and the power unit; Equipped with Lawnmower.

2. The power shaft of the drive wheel or drive wheel provided on the traveling part and the support shaft of the connection mechanism part are a common shaft. The grass cutter according to claim 1.

3. a lifting assisting section disposed between the lower frame section and the upper frame section, which assists the lifting and lowering operation of the upper frame section and can be stopped at any position; 3. The grass cutter according to claim 1 or 2.

4. The structure is applicable to a brush cutter including a lower frame part having a running part and a gap or opening formed in an inner region thereof, and an upper frame part disposed above the lower frame part, a connection mechanism portion disposed at the front or rear of the vehicle body in the traveling direction, which axially connects the upper frame portion and the lower frame portion, and which connects the upper frame portion so that the upper frame portion can be raised and lowered around a support shaft that intersects with the traveling direction of the vehicle body as a rotation fulcrum; a grass cutting unit attached to the upper frame portion and capable of cutting grass with a rotary grass cutting blade located below the upper frame portion when the upper frame portion is in a lowered state; Equipped with Lifting structure for lawn mower.

5. A brush cutter is used, which includes a lower frame section, a running section, an upper frame section, a connecting mechanism section that pivots and connects the upper frame section and the lower frame section so that they can be raised and lowered, a brush cutter section that is attached to the upper frame section and has a rotary brush cutter blade, a power section, and a control section, The control unit controls the power unit, and the power unit drives traveling units disposed on both the left and right sides of the lower frame unit in the traveling direction of the machine body, and the traveling units cause the brush mower to travel to a working area. the control unit controls the mowing unit, and the mowing unit is located below the upper frame unit when the upper frame unit is in a lowered state, and performs mowing work with the rotary mowing blade exposed below the machine body through a gap or opening formed in an inner region of the lower frame unit when in the lowered state; During the mowing work, if an event occurs in which a rotation obstructing object that inhibits the rotation of the rotary mower blade becomes entangled with the rotary mower blade, making it unable to rotate, or if an event occurs in which a part of the rotary mower blade needs to be replaced, the upper frame part is raised via a connection mechanism part that is disposed in front or behind the traveling direction of the body of the mower, axially attaches the upper frame part to the lower frame part, and connects the upper frame part so that it can be raised and lowered around a support shaft that intersects with the traveling direction of the body of the mower as a rotation fulcrum, thereby exposing the mowing part, and maintenance work can be performed to remove the rotation obstructing object or replace the part of the rotary mower blade. How to mow.

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