Agricultural machinery

Abstract

The objective is to provide an agricultural implement that facilitates posture adjustment by providing a mechanism that adjusts the forward-to-backward tilt of the work part according to the forward-to-backward tilt of the work part relative to the work surface, so that the agricultural implement can be in a proper working posture. [Solution] An agricultural implement A comprising a mounting part 1 that can be connected to a coupling mechanism that can move up and down on a vehicle body, and a work part 4 that receives power from the vehicle body and performs a predetermined task, wherein the agricultural implement A has a posture adjustment means for adjusting the inclination of the work part 4 in the front-rear direction so that the inclination state of the work part 4 with respect to the work surface is a predetermined inclination state.

Description

Technical Field

[0001] The present invention relates to an agricultural working machine, particularly an agricultural working machine that connects a working part to a traveling vehicle body such as a tractor.

Background Art

[0002] Conventionally, an agricultural working machine that can perform work by connecting a working part to a traveling vehicle body such as a tractor, for example, an offset mower, is known. (Patent Document 1) In an offset mower as shown in Patent Document 1, a mounting part attached to a connecting part such as a three-point link of a traveling vehicle body like a tractor and the working part are connected by an offset mechanism. With this offset mechanism, in a state where the working part is offset and moved to the outer side of the traveling vehicle body, flat cutting is performed to cut grass on a horizontal plane, and further, in a state where the working part is tilted and moved, slope cutting is performed to cut grass on an inclined plane. For an offset mower, it is necessary to further change the height of the machine body with respect to the traveling vehicle body during flat cutting and slope cutting. Also, even during slope cutting, it is necessary to change the height of the agricultural working machine with respect to the traveling vehicle body during work on an upward inclined slope and during work on a downward inclined slope.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In a three-point linkage mechanism connecting a vehicle body to an agricultural implement, raising or lowering the implement also changes the tilt angle of the implement in the front-to-back direction. This changing tilt angle can cause problems during operation. For example, when mowing grass with an offset mower, if the working section tilts backward, the gap between the front cover of the working section and the work surface (ground) becomes larger, which may cause flying debris from the mowing blade. Conversely, if the working section tilts forward, the front cover of the working section is more likely to come into contact with the work surface, or the mowing blade may start to scrape the work surface, leading to increased wear on the mowing blade and placing a greater load on the working section.

[0005] In conventional agricultural machinery, the operator adjusted the length of the top link of the three-point linkage mechanism by extending or retracting it, thereby maintaining the front-to-back tilt angle of the agricultural machinery at the appropriate angle. Adjusting the length of the top link required the operator to first move the agricultural implement into the desired working position as a test from the driver's seat of the vehicle, then get out of the vehicle and visually check the working position while extending or retracting the top link. This process was cumbersome and inefficient. Furthermore, there were limitations to the range of adjustment possible by extending or retracting the top link, and it was not always possible to adjust the implement to the correct position solely by extending or retracting the top link.

[0006] Therefore, the object of the present invention is to provide an agricultural implement that facilitates posture adjustment of the implement by providing a mechanism that adjusts the inclination of the work part in the front-rear direction according to the inclination of the work part in the front-rear direction with respect to the work surface, so that the implement can be in an appropriate working posture. [Means for solving the problem]

[0007] To solve these problems, the present invention has the following configuration. A mounting part that can be connected to a coupling mechanism that allows the vehicle body to move up and down, An agricultural machine comprising a work unit that receives power from the aforementioned vehicle body and performs predetermined tasks, An agricultural implement characterized by having posture adjustment means for adjusting the inclination of the work part in the front-rear direction so that the inclination of the work part in the front-rear direction with respect to the work surface is a predetermined inclination. [Effects of the Invention]

[0008] In the agricultural implement of the present invention, the posture of the agricultural implement can be easily adjusted by providing a mechanism that adjusts the inclination of the work part in the front-to-back direction according to the inclination of the work part in the front-to-back direction with respect to the work surface, so that the agricultural implement can be in an appropriate working posture. [Brief explanation of the drawing]

[0009] [Figure 1] This is a view from above of the lawnmower A according to Embodiment 1 of the present invention. [Figure 2] This is a view of the lawnmower A according to Embodiment 1 of the present invention, seen from the left. [Figure 3] This is a view of the work section 4 of the lawnmower A according to Embodiment 1 of the present invention, as seen from the front. [Figure 4] This is a view from above of the grass trimmer B according to Embodiment 2 of the present invention. [Figure 5] This is a view of the grass trimmer B of Embodiment 2 of the present invention, seen from the left. [Figure 6] This is a view of the grass trimmer C according to Embodiment 3 of the present invention, seen from the left. [Figure 7] This is a view of the lawnmower D, a modified example of the present invention, from the left. [Figure 8] This figure shows a working section tilt detection means 8 of a modified example 2 of the present invention. [Modes for carrying out the invention]

[0010] [Embodiment 1] Hereinafter, a lawnmower A of Embodiment 1 according to the present invention will be described with reference to the drawings. Note that the agricultural implement is not limited to a lawnmower, but can be any implement that is connected to a connecting means such as a three-point linkage mechanism of a vehicle body, and whose front and rear tilt angles are changed by the raising and lowering of the three-point linkage mechanism. In the following explanation, the same symbols in different figures indicate parts with the same function, and redundant explanations in each figure will be omitted as appropriate. Furthermore, for the sake of explanation, we will use terms indicating direction such as up, down, forward, backward, right, and left. However, the direction in which gravity acts is downward, and the opposite is upward. Also, the direction in which a moving vehicle is moving is forward, and the opposite is backward. In addition, looking forward, the right side is right and the left side is left.

[0011] Figures 1 to 3 show the stored state of the lawnmower A of Embodiment 1, respectively. Figure 1 is a view of the lawnmower A from above, Figure 2 is a view from the left, and Figure 3 is a view of only the work section 4 from the front. The upper part of Figure 1(b) is an enlarged view of the right end of the work section 4 in Figure 1(a), and the lower part of Figure 1(b) is an enlarged view of the left end of the work section 4. Figure 2(b) is an enlarged view of the work section 4 in Figure 2(a). The left diagram in Figure 3(b) is an enlarged view of the right end of the work section 4 in Figure 3(a), the middle diagram in Figure 3(b) is an enlarged view of the central part of the work section 4 in Figure 3(a), and the right diagram in Figure 3(b) is an enlarged view of the left end of the work section 4 in Figure 3(a). In Figure 3, the front cover 42, which will be described later, is shown by a dashed line.

[0012] [Overall structure] The lawnmower A of Embodiment 1 is connected to the rear of a vehicle body (not shown) such as a tractor, and performs grass cutting work while moving forward as the vehicle body moves. It is equipped with a mounting part 1, an offset mechanism part 2, a power transmission part 3, a working part 4, and a tilt mechanism part 5. The work unit 4 can be moved from the rear position of the vehicle body to a position offset to the right of the vehicle body by the operation of the offset mechanism 2. For this reason, the offset mechanism 2, the power transmission unit 3, and the tilt mechanism 5 are located above and to the left of the shield cover 43 of the work unit 4, which will be described later. In this embodiment, grass cutting work can be performed at any position between the rear position of the vehicle body and the position offset to the right of the vehicle body. Note that the state where the working unit 4 is located at the rear position of the traveling vehicle body is referred to as the storage state, and the state where the working unit 4 is located on the right side of the traveling vehicle body is referred to as the offset state. Also, it is not limited to the mowing operation being possible in both the storage state and the offset state. For example, the mowing operation may not be possible in the storage state, or the mowing operation may be possible only in a specific position among the storage state and the offset state, etc. The mowing operation may be performed only within a specific range or at a specific position.

[0013] [Mounting part] The mounting part 1 is connected to a three-point link mechanism (linking mechanism: not shown in FIGS. 1 to 3) provided at the rear of the traveling vehicle body. The three-point link mechanism is usually composed of a top link, a lift rod, a lower link, etc. Since the three-point link mechanism is a known mechanism, detailed description thereof is omitted. The mounting part 1 of the mower A is connected to the traveling vehicle body so as to be vertically movable by a three-point link mechanism. The mounting part 1 includes a hitch frame 11 extending in the left-right direction which is the width direction of the traveling vehicle body. The hitch frame 11 has a top mast connected to the top link and a lower link connecting part connected to the lower link, and is configured to be connectable to a three-point link mechanism provided at the rear of the traveling vehicle body via an auto hitch 7 (not shown in FIGS. 1 to 3). Note that it is also possible to adopt a configuration in which the mounting part 1 is directly connected to the three-point link mechanism of the traveling vehicle body without passing through the auto hitch 7. A gear box 12 is provided at the lower center of the hitch frame 11, and a mower input shaft 13 for receiving power from the traveling vehicle body is provided in this gear box 12. Power is transmitted to the mower input shaft 13 via two universal joints and a power transmission shaft (both not shown) from a PTO shaft (not shown) provided on the traveling vehicle body. The power transmission shaft is configured to be telescopic, and together with the two universal joints, it can transmit power within a predetermined range even if the distance, height, angle, etc. between the PTO shaft and the mower input shaft 13 change.

[0014] [Offset mechanism part] The offset mechanism 2 is a mechanism for moving the work unit 4 between a stowed state and an offset state (offset movement). The offset mechanism 2 includes an offset frame 21, a link rod 22, a support frame 23, and an offset cylinder 24. In this embodiment, the support frame 23 supports the work unit 4 and is configured to offset to the right together with the work unit 4.

[0015] One end (front) of the offset frame 21 and the link rod 22 is rotatably connected to the hitch frame 11, and the other end (rear) of the offset frame 21 and the link rod 22 is rotatably connected to the support frame 23. With this configuration, the hitch frame 11, the offset frame 21, the link rod 22, and the support frame 23 form a parallelogram-shaped link mechanism (parallel link mechanism) with their respective pivot points as vertices. This link mechanism allows the offset mechanism 2 to offset the working section 4 while maintaining the angle of the working section 4 with respect to the direction of travel of the vehicle body.

[0016] The offset cylinder 24 is the power source (actuator) for the offset mechanism 2, and can be composed of, for example, an electric hydraulic cylinder used in this embodiment 1, a hydraulic cylinder, an electric cylinder, etc. One end of the offset cylinder 24 is connected to the hitch frame 11, and the other end is connected to the rear of the offset frame 21. The offset mechanism 2 is driven by the extension and retraction of the offset cylinder 24, and the amount of offset (amount of movement in the offset direction) of the work section 4 can be controlled. In this embodiment 1, the working section 4 is in a retracted state when the offset cylinder 24 is retracted, and in an offset state when it is extended. However, the opposite configuration is also possible, where the working section 4 is in a retracted state when the offset cylinder 24 is extended, and in an offset state when it is retracted. In this embodiment 1, the work unit 4 is structured to be offset to the right outer side of the vehicle body, but it may also be structured to be offset to the left outer side, or even to be offset to both the left and right outer sides.

[0017] [Tilt mechanism] The tilt mechanism 5 is a mechanism for rotating the work section 4 vertically around a pivot axis (not shown) that extends in the front-rear direction, which is the direction of travel of the vehicle body. The tilt mechanism 5 consists of a pivot axis, a support arm 51, a tilt cylinder 52, and a pivot axis bracket 53 (see Figure 2). The work unit 4 is rotated by the tilt mechanism 5 so that its right end is facing downwards (clockwise when viewed from the rear), allowing the work unit 4 to perform grass cutting work on inclined surfaces (such as slopes) that are located below the running surface of the vehicle body. Furthermore, the work unit 4 can be rotated by the tilt mechanism 5 so that its right end is facing upward (counterclockwise when viewed from the rear), allowing the work unit 4 to perform grass cutting on inclined surfaces (such as slopes) that are positioned above the running surface of the vehicle body. The structure of the tilt mechanism 5 allows the work section 4 to rotate vertically at any position between the stowed state and the maximum offset state. Furthermore, the ability to rotate the work unit 4 vertically at any position between the stored state and the maximum offset state is not limited to this. For example, it may be possible to restrict vertical rotation to a specific range or position, such as not being able to rotate vertically in the stored state, or not being able to rotate vertically unless it is offset by a predetermined amount or more. Furthermore, in this embodiment 1, the right end of the work section 4 is positioned downward when the tilt cylinder 52 is retracted and upward when it is extended. However, the opposite configuration is also possible: the right end of the work section 4 may be positioned downward when the tilt cylinder 52 is extended and upward when it is retracted.

[0018] The pivot shaft of the tilt mechanism 5 is fixed at its rear end to the front of the front gear case 31, which will be described later, so as to be concentric with the working section input shaft, which will be described later. The support arm 51 is fixed to the pivot shaft on its upper side. In other words, the pivot shaft and the support arm 51 are fixed so as not to rotate relative to the front gear case 31. Furthermore, the front end of the pivot shaft is rotatably connected to a pivot shaft bracket 53 provided on the front side of the upper surface of the shield cover 43. With this configuration, the pivot shaft bracket 53 is rotatable around the pivot shaft relative to the support arm 51 (front gear case 31) (see Figure 2). Furthermore, one end of a tilt cylinder 52, which will be described later, is pivotally supported on the lower side of the support arm 51. In this embodiment 1, an electric hydraulic cylinder is used as the tilt cylinder 52. However, the tilt cylinder 52 is not limited to an electric hydraulic cylinder; a hydraulic cylinder, electric cylinder, etc., may also be used. The other end of the tilt cylinder 52 is pivotally supported by a tilt cylinder mounting portion 431 attached to the shield cover 43, which will be described later. Specifically, one end of the tilt cylinder 52 is connected to the front gear case 31 to which the support arm 51 is fixed, and the other end is connected to the work section 4. The front gear case 31 is connected to the offset mechanism 2, as will be described later, and the extension and retraction of the tilt cylinder 52 causes the work section 4 to rotate relative to the offset mechanism 2.

[0019] [Power transmission section] The power transmission unit 3 is a mechanism for transmitting power from the vehicle body, received by the grass cutter input shaft 13 of the mounting unit 1, to the work unit 4. In this embodiment of grass cutter A, a chain drive mechanism is employed in the power transmission unit 3. Specifically, the chain drive mechanism has at least a drive sprocket, a driven sprocket, and a roller chain (none of which are shown) wrapped around them. The work unit 4 receives power from the driven sprocket via multiple power transmission means and performs grass cutting work. The chain drive mechanism is located above the offset mechanism section 2 (offset frame 21). The power transmission section 3 is connected to the driven sprocket and includes a shaft (not shown) extending downward, a first bevel gear (not shown) connected to the lower end of this shaft, and a front gear case 31 housing this first bevel gear. Furthermore, the power transmission unit 3 may use a belt drive mechanism instead of the chain drive mechanism described above. It is also possible to use a combination of a power transmission shaft and a universal joint as the power transmission unit 3. Furthermore, the power transmission unit 3 may be omitted, and the grass trimmer A may be equipped with a drive source such as an electric motor or a hydraulic motor, and the power of the drive source may be transmitted directly to the work unit 4, or the power of the drive source may be transmitted to the work unit 4 via other power transmission means.

[0020] [Working Department] The work unit 4 is connected to the offset mechanism 2 via the front gear case 31. As described above, the work unit 4 moves in an offset position while maintaining a constant angle with respect to the direction of travel of the vehicle body by the extension and retraction of the offset cylinder 24. The support frame 23 is rotatably connected to the offset frame 21 and is connected to the work unit 4. The work unit 4 includes a work rotor 41, a front cover 42, a shield cover 43, a side plate 44, a work unit input shaft (not shown), a rear gear case 45, a cutting blade drive unit 46, and a posture adjustment means (details will be described later). The working rotor 41 includes a rotating shaft 41a (a rotating shaft to which the grass-cutting blades are attached) positioned between the side plates 44 at both ends, and a plurality of grass-cutting blades (not shown) arranged radially on the rotating shaft 41a. The rotating shaft 41a extends in a horizontal direction perpendicular to the direction of travel of the vehicle body.

[0021] The work unit 4 rotates the rotating shaft 41a to cut weeds and other vegetation with the grass-cutting blade. In this embodiment 1, as shown by the arrow in Figure 2, the rotating shaft 41a rotates clockwise when viewed from the left. As a result, the grass cutting blade cuts weeds and other vegetation by striking them from rear to front below the rotating shaft 41a. The cut weeds and other vegetation pass through the front cover 42, shield cover 43, and side plate 44, and are ultimately discharged to the rear through the gap between the rear end of the shield cover 43 and the work surface (ground surface).

[0022] The shield cover 43 is a cover member positioned to cover the front, top, and rear of the work rotor 41. The front cover 42 seals the gap between the front end of the shield cover 43 and the work surface, preventing weeds cut by the mowing blade, soil attached to the weeds, and small stones lying on the work surface from being scattered forward. The cut weeds and other vegetation remain briefly inside the front cover 42, shield cover 43, and side plate 44, where they are finely shredded by the cutting blades and finally discharged to the rear. The side plate 44 rotatably supports the rotating shaft 41a via ball bearings or the like, and also supports the shield cover 43. The side plate 44 also supports the front cover 42 via a gauge support arm 49, which will be described later. In this embodiment, the cutting blade drive unit 46 is provided on the left outer side of the left end of the side plate 44 of the shield cover 43.

[0023] The cutting blade drive unit 46 of this embodiment 1 includes a drive pulley, a driven pulley, a belt, and a tensioner (none of which are shown). In the cutting blade drive unit 46, power transmitted from the working unit input shaft is transmitted to the drive pulley shaft (input shaft of the cutting blade drive unit), then transmitted from the drive pulley to the driven pulley via a belt, and finally transmitted from the driven pulley shaft (output shaft of the cutting blade drive unit) to the rotating shaft 41a, driving the working rotor 41. The driven pulley shaft and the rotating shaft 41a are concentric. In this embodiment, a belt drive is used for the cutting blade drive unit 46, but the system is not limited to this, and any power transmission means such as a chain drive or gear drive may be used.

[0024] The power transmission means within the work section 4 will now be explained. The power transmitted to the driven sprocket of the power transmission unit 3 is transmitted to the work unit input shaft (not shown), which is the power input of the work unit 4, via the first bevel gear, which is located at the lower end of the shaft of the driven sprocket and is the power output of the power transmission unit 3. The work unit input shaft is housed in the front gear case 31 and in the rear gear case 45, which is attached to the shield cover 43. The rear gear case 45 houses a second bevel gear (not shown) located at the rear end of the working unit input shaft. The front gear case 31 and the rear gear case 45 are connected so as to be rotatable relative to each other around the axis of the working section input shaft. This allows power to be transmitted from the first bevel gear to the second bevel gear via the working section input shaft, regardless of the tilt movement of the working section 4. Power is transmitted from the second bevel gear in the rear gear case 45 to the cutting blade drive unit 46, and the power transmitted to the cutting blade drive unit 46 is then transmitted to the rotating shaft 41a of the working rotor 41.

[0025] [Posture adjustment means] The posture adjustment means for the work section 4 includes a rear gauge roller 47, a front gauge wheel 48, and a gauge support arm 49. The rear gauge roller 47 and the front gauge wheel 48 are attached to the gauge support arm 49. The gauge support arm 49 is pivotably supported on two side plates 44 of the work section 4, and the gauge support arm 49 is configured to pivot so that both the rear gauge roller 47 and the front gauge wheel 48 make contact with the work surface. This adjusts the height of the brush cutter A, i.e., the distance between the work section 4 and the work surface, to an appropriate distance. In addition, by pivoting so that both the rear gauge roller 47 and the front gauge wheel 48 make contact with the work surface, the front cover 42 can properly close the gap between the shield cover 43 and the work surface. The gauge support arm 49 consists of a pair of left and right gauge support arms 49L and 49R, which are pivotably supported on pivot points 44a provided on each of the two side plates 44. The gauge support arm 49 extends rearward and forward from the pivot point 44a, and bends at the pivot point 44a to form a roughly "V" shape when viewed from the side. The rear gauge roller 47 is rotatably supported at the rear of a pair of left and right gauge support arms 49L and 49R, and the front gauge wheel 48 is rotatably supported at the front of a pair of left and right gauge support arms 49L and 49R. In this embodiment 1, the pivot point 44a is provided concentrically with the rotation axis 41a of the work rotor 41. Furthermore, a front cover 42 is attached to the portion of the gauge support arm 49 that extends forward from the pivot point 44a, so as to span across the two gauge support arms 49L and 49R. Furthermore, the rear gauge roller 47 and front gauge wheel 48 can be mounted on the gauge support arm 49 in an adjustable position so that the distance between the work section 4 and the work surface, i.e., the cutting height, can be adjusted. Alternatively, the gauge support arm 49 can be mounted on the side plate 44 in an adjustable position.

[0026] The rear gauge roller 47 is a roller that is stretched across two gauge support arms 49L and 49R and is pivotally supported at both ends. The rear gauge roller 47 has approximately the same width as the work section 4 and is a driven roller that rotates in accordance with the work section 4 as it moves along with the vehicle body. In this embodiment 1, it rotates counterclockwise when viewed from the left. In addition, the rear gauge roller 47 in this embodiment is fitted with a scraper 47a for removing weeds and other debris adhering to the roller surface. The scraper 47a is stretched between a pair of gauge support arms 49L and 49R at the rear end of the gauge support arm 49, and is positioned along the width direction of the rear gauge roller 47 so that the tip of the scraper 47a faces the surface of the rear gauge roller 47.

[0027] The front gauge wheel 48 is a driven wheel that rotates in accordance with the working section 4, which moves along with the running body of the vehicle. In this embodiment 1, it rotates counterclockwise when viewed from the left. In this embodiment 1, the front gauge wheels 48 have a total of three gauge wheels: a left front gauge wheel 48L and a right front gauge wheel 48R, one each attached to the left and right gauge support arms 49L and 49R, respectively, and a central front gauge wheel 48C attached to the center of the front gauge wheel support frame 491 that is installed between the left and right gauge support arms 49L and 49R. As shown in Figure 2, the left front gauge wheel 48L and the right front gauge wheel 48R are positioned rearward in a side view relative to the central front gauge wheel 48C. When mowing slopes or in other work situations, one or both of the left and right ends of the work unit 4 may not be on the work surface. However, by using multiple front gauge wheels 48, it becomes possible to ensure that at least one of the multiple front gauge wheels 48 is in contact with the work surface.

[0028] The left front gauge wheel 48L and the right front gauge wheel 48R are rotatably supported at the lower ends of the front gauge wheel support parts 48L1 and 48R1, which are attached to the front ends of the left and right gauge support arms 49L and 49R, respectively. The central front gauge wheel 48C is rotatably supported at the lower end of the front gauge wheel support portion 48C1, which is mounted on the front gauge wheel support frame 491 so as to be adjustable in left-right position. This makes it possible to mount the central front gauge wheel 48C in an appropriate left-right position depending on the work method and the condition of the work surface. The left front gauge wheel 48L, the right front gauge wheel 48R, and the center front gauge wheel 48C are mounted so that the height of their respective contact points, i.e., the height of the lower ends of the left front gauge wheel 48L, the right front gauge wheel 48R, and the center front gauge wheel 48C are the same. In this embodiment 1, one central front gauge wheel 48C is attached, but two or more can be attached.

[0029] [Posture adjustment] In the lawnmower A of this embodiment 1, the vertical position (tilting posture) of the front cover 42, which is part of the work section 4, is adjusted according to the front-to-back tilt angle (tilting state) of the work section 4 with respect to the work surface. Even if the front-to-back tilt angle of the lawnmower A changes, the gap between the front cover 42 of the work section 4 and the work surface is maintained at a predetermined appropriate size. This prevents flying stones and other debris from being scattered in front of the work section 4 due to an increase in the gap between the front cover 42 and the work surface, and also prevents the front cover 42 from touching the work surface due to a decrease in the gap between the front cover 42 and the work surface. The rear gauge roller 47 and front gauge wheel 48 are rotatably supported by a pair of left and right gauge support arms 49. The work unit 4 and the gauge support arms 49 are rotatably connected to each other at a pivot point 44a of the gauge support arms 49, which is concentric with the rotation axis 41a of the work rotor 41. As a result, when the three-point linkage mechanism is lowered, both the rear gauge roller 47 and the front gauge wheel 48 can make contact with the ground regardless of the inclination of the work unit 4 in the front-rear direction. Specifically, when the three-point linkage mechanism is lowered and the brush cutter A is lowered, either the rear gauge roller 47 or the front gauge wheel 48 will make contact with the work surface. With either the rear gauge roller 47 or the front gauge wheel 48 in contact with the work surface, if the three-point linkage mechanism is lowered further and the brush cutter A is lowered, the gauge support arms 49 will swing (rotate) around the pivot point 44a, and the other rear gauge roller 47 or front gauge wheel 48 that was not in contact with the work surface will also make contact with the work surface. At this time, since the front cover 42 of the work section 4 is attached to the gauge support arm 49, the front cover 42 also swings in accordance with the swing of the gauge support arm 49. Furthermore, when the three-point linkage mechanism is lowered and the brush cutter A is lowered, it is possible that both the rear gauge roller 47 and the front gauge wheel 48 may simultaneously make contact with the work surface. Furthermore, in the grass trimmer A of this embodiment 1, when the rear gauge roller 47 and the front gauge wheel 48 make contact with the ground, the descent of the three-point linkage mechanism is stopped, and the working section 4 is configured to be in the correct position (height) and posture relative to the working surface. As a result, the grass cutting blade is also held in the correct position and posture relative to the working surface, preventing the grass cutting blade from colliding with the working surface and allowing it to be held at a predetermined cutting height. Furthermore, since the front cover 42 is also attached to the gauge support arm 49, it is held in the correct position relative to the work surface, and the gap between the front cover 42 and the work surface can be maintained at an appropriate size.

[0030] [Embodiment 2] Figure 4 is a view of the grass trimmer B of Embodiment 2 of the present invention from above, and Figure 5 is a view of the grass trimmer B of Embodiment 2 from the left. The upper part of Figure 4(b) is an enlarged view of the right end of the work section 4 in Figure 4(a), and the lower part of Figure 4(b) is an enlarged view of the left end of the work section 4. Figure 5(b) is an enlarged view of the front side of the work section 4 in Figure 5(a). In this second embodiment, the forward and backward tilting posture of the grass trimmer B that occurs when the grass trimmer B is raised and lowered by the three-point linkage mechanism 6 is adjusted to an appropriate tilting posture by using an extendable hydraulic cylinder as the top link 61 of the three-point linkage mechanism 6. In addition to a hydraulic cylinder, an electric hydraulic cylinder, an electric cylinder, etc. may also be used. The three-point linkage mechanism 6 is similar to known configurations, except that a hydraulic cylinder is used as the top link 61. Figures 4 and 5 show only the top link 61 and lower link 62. The mounting section 1, offset mechanism section 2, power transmission section 3, work section 4, and tilt mechanism section 5 of the brush cutter B in this second embodiment are the same as those of the mounting section 1, offset mechanism section 2, power transmission section 3, work section 4, and tilt mechanism section 5 in the first embodiment. However, in the brush cutter B of this second embodiment, the front cover 42 of the work section 4 is fixed to the shield cover 43, unlike in the first embodiment (its vertical movement position is not adjustable). The lawnmower B is connected to the three-point linkage mechanism 6 via an auto hitch 7 (also called a quick hitch or one-touch hitch). As will be described in detail later, the configuration of the posture adjustment means in this embodiment 2 differs from that of the posture adjustment means in embodiment 1.

[0031] The rear gauge roller 47 has the same configuration as a conventional gauge roller and is a roller that is rotatably supported so as to be stretched across the rear gauge roller support arm 49a. The rear gauge roller support arm 49a has a pair of left and right rear gauge roller support arms 49aL and 49aR that are rotatably supported around pivot points 44b provided on each of the two side plates 44. In this embodiment 2, the pivot point 44b is provided at the lower part of the work section 4, and the rear gauge roller support arm 49a can be fixed at multiple rotational positions. The rear gauge roller 47 is supported so as to span across two rear gauge support arms 49aL and 49aR, and is a roller having approximately the same width as the working section 4. The rear gauge roller 47 is a driven roller that rotates in accordance with the movement of the work section 4, and in this embodiment 2, it rotates counterclockwise when viewed from the left. In addition, the rear gauge roller 47 in this embodiment is equipped with a scraper member (not shown in Figures 4 and 5) for removing weeds and other debris adhering to the roller surface. The scraper member is stretched between a pair of rear gauge roller support arms 49aL and 49aR at the rear end of the rear gauge roller support arm 49a and is positioned to face the rear gauge roller 47. The rear gauge roller support arm 49a is configured to change the height of the rear gauge roller 47 by changing its rotational position and fixing it, thereby allowing adjustment of the cutting height of the grass cutting blade.

[0032] [Posture adjustment means] In this second embodiment, the posture adjustment means for the work unit 4 includes a work unit tilt detection means 8 and a top link 61. The work section tilt detection means 8 includes a front gauge wheel 48, a front gauge wheel support arm 49b, and a front gauge wheel detector 81. The front gauge wheel 48 is a driven wheel that rotates in accordance with the working section 4, which moves along with the running body of the vehicle. In this embodiment 2, it rotates counterclockwise when viewed from the left. The front gauge wheels 48 have a left front gauge wheel 48L and a right front gauge wheel 48R, which are attached one to each of the left and right front gauge wheel support arms 49bL and 49bR, respectively. When mowing slopes, depending on the work method, one of the left or right ends of the work unit 4 may not be on the work surface. However, by using multiple front gauge wheels 48, it becomes possible to ensure that at least one of the multiple front gauge wheels 48 is in contact with the work surface. The left front gauge wheel 48L and the right front gauge wheel 48R are rotatably supported at the lower ends of the front gauge wheel support parts 48L1 and 48R1, which are attached to the front ends of the left and right front gauge wheel support arms 49bL and 49bR, respectively. The front gauge wheel support arms 49bL and 49bR are attached to the left and right side plates 44 of the work section 4 so as to protrude forward. The front ends of the front gauge wheel support arms 49bL and 49bR support the front gauge wheel support sections 48L1 and 48R1 so that they can move up and down. The front gauge wheels 48L and 48R are mounted to the front gauge wheel support arms 49bL and 49bR so as to be vertically movable, together with the front gauge wheel support parts 48L1 and 48R1. The front gauge wheels 48L and 48R are constantly subjected to a downward force due to the weight of the front gauge wheels 48L and 48R and the weight of the front gauge wheel support parts 48L1 and 48R1. Stoppers (not shown) are provided at the upper ends of the front gauge wheel support parts 48L1 and 48R1 to prevent them from coming off the front gauge wheel support arms 49bL and 49bR.

[0033] The front gauge wheel detector 81 comprises a front gauge wheel detector body 81a and a front gauge wheel detection arm 81b. The front gauge wheel detector body 81a is fixed to the rear end side of the front gauge wheel support arms 49bL and 49bR, and the front gauge wheel detection arm 81b has its base end attached to the front gauge wheel detector body 81a and its tip end engaged with the upper end of the front gauge wheel support parts 48L1 and 48R1. The front gauge wheel detector body 81a detects the rotational position of the front gauge wheel detection arm 81b. The front gauge wheel detection arm 81b rotates in accordance with the vertical movement of the front gauge wheel support parts 48L1 and 48R1, and the front gauge wheel detector body 81a detects the rotational position, thereby detecting the vertical position of the front gauge wheel 48. The front gauge wheel detector body 81a can be constructed using a known angle sensor such as a potentiometer or rotary encoder. In this embodiment 2, the vertical position of the front gauge wheel 48 is detected, and the height of the front end of the work section 4 relative to the work surface is detected, thereby detecting the inclination of the work section 4 in the front-rear direction relative to the work surface. However, as a configuration to detect the height of the front end of the work section 4 relative to the work surface, an ultrasonic sensor or infrared sensor may be attached to the front end of the work section 4, and the height of the front end of the work section 4 relative to the work surface may be directly detected using the ultrasonic sensor or infrared sensor. The detection signal from the front gauge wheel detector 81 is transmitted via a lawnmower control device (not shown) installed on the lawnmower B, or directly to a vehicle control device (not shown) installed on the vehicle body.

[0034] [Posture adjustment] In this second embodiment, the tilt of the grass trimmer B in the front-rear direction that occurs when the grass trimmer B is raised and lowered by the three-point linkage mechanism 6 is detected by the work section tilt detection means 8, and the top link 61 of the three-point linkage mechanism 6 is extended or retracted to adjust to an appropriate tilt. As the three-point linkage mechanism 6 is lowered, the rear gauge roller 47 can make contact with the ground regardless of the inclination of the work section 4 in the front-rear direction, and the lowering of the three-point linkage mechanism 6 is stopped when the rear gauge roller 47 makes contact with the ground. When the descent of the three-point linkage mechanism 6 is stopped, the front gauge wheel 48 of the brush cutter B is also in contact with the ground, and the vertical position of the front gauge wheel 48 in this state, that is, the tilt angle of the work section 4 in the front-rear direction, can be detected by the work section tilt detection means 8. The detection signal from the front gauge wheel detector 81 is transmitted to the mower control device installed on the mower B. The mower control device stores the relationship between the detection signal and the extension / retraction amount of the top link 61, and based on the detection signal received from the front gauge wheel detector 81, transmits a control signal to the vehicle control device to extend or retract the top link 61 so that the tilt of the work section 4 in the front-rear direction is appropriate. The vehicle control device controls the extension or retraction of the top link 61 based on the transmitted extension / retraction amount of the top link 61.

[0035] Furthermore, the vehicle control unit stores the relationship between the detection signal and the extension / retraction amount of the top link 61, and can receive the detection signal detected by the front gauge wheel detector 81 via the lawnmower control unit, or directly from the front gauge wheel detector 81 (by wireless or other means), and the vehicle control unit can extend or retract the top link 61. Communication between the lawnmower control unit and the vehicle control unit may be wired or wireless. Alternatively, the lawnmower control device may receive a detection signal, determine whether to extend or retract the top link 61 based on the received detection signal, and transmit the determination result to the vehicle control device, which then extends or retracts the top link 61. In this case, the lawnmower control device has a predetermined appropriate value for the detection signal that ensures the front-to-rear inclination of the work unit 4 is appropriate, and transmits a control signal to the vehicle control device to extend or retract the top link 61 until the detection signal reaches the appropriate value. In other words, it performs feedback control to extend or retract the length of the top link 61. Alternatively, the vehicle control device may have a predetermined appropriate value for the detection signal that ensures the front-to-rear inclination of the work unit 4 is appropriate, and the vehicle control device may receive the detection signal and perform similar feedback control based on the received detection signal.

[0036] As described above, when the front-to-back tilt angle of the brush cutter B is adjusted to an appropriate tilt, the gap between the front cover 42 of the work section 4 and the work surface is maintained at a predetermined appropriate size. This prevents the gap from becoming too large, which would cause flying stones and other debris to scatter in front of the work section 4. It also prevents the gap from becoming too small, which would cause the front cover 42 to come into contact with the work surface. Furthermore, it prevents wear caused by the brush cutter blade scraping the work surface due to the work section 4 tilting forward. In this embodiment 2 of the grass trimmer B, since the tilt angle in the front-rear direction of the grass trimmer B is adjusted to an appropriate tilt, the front cover 42 of the work section 4 does not need to be vertically adjustable to the shield cover 43, as in embodiment 1, and is fixed to the shield cover 43. Furthermore, the front cover 42 can also be formed integrally with the shield cover 43.

[0037] [Embodiment 3] Figure 6 is a view of the grass trimmer C of Embodiment 3 of the present invention, as seen from the left. In this third embodiment, a mounting unit 1 having two frames at the front and rear is used, and the tilt of the grass trimmer C in the front-rear direction that occurs when the grass trimmer C is raised and lowered by a three-point linkage mechanism (not shown in Figure 6) is adjusted to an appropriate tilted posture by changing the tilt between the two frames of the mounting unit 1. The offset mechanism 2, power transmission unit 3, work unit 4, tilt mechanism 5, and work unit tilt detection means 8 of the brush cutter C of this embodiment 3 are the same as those of the offset mechanism 2, power transmission unit 3, work unit 4, tilt mechanism 5, and work unit tilt detection means 8 of embodiment 2. The brush cutter C is connected to a three-point linkage mechanism via an auto hitch (not shown in Figure 6). Since the mounting portion 1 in this third embodiment differs from that in the second embodiment, the mounting portion 1 will be described below.

[0038] The mounting section 1 consists of a rear frame 11a and a front frame 11b arranged front to back. The lower ends of the rear frame 11a and the front frame 11b are connected by a pivot shaft 16 that extends in a left-right direction perpendicular to the direction of travel, allowing them to tilt relative to each other in the front-rear direction. The rear frame 11a corresponds to the hitch frame 11 of Embodiment 2. The front frame 11b includes a three-point linkage mechanism, a coupling section connected to an auto hitch, and a power shaft 14 that receives power from the PTO shaft of the vehicle body and outputs it to the brush cutter input shaft 13 provided on the rear frame 11a. The rear frame 11a and the front frame 11b are connected so as to be rotatable relative to each other in the front-rear direction around a pivot axis 16 that extends in the left-right direction perpendicular to the direction of travel, and the rear frame 11a is tiltable in the front-rear direction relative to the front frame 11b. The upper ends of the rear frame 11a and the front frame 11b are connected by a connecting cylinder 17. By extending and retracting this connecting cylinder 17, the inclination angle of the rear frame 11a relative to the front frame 11b in the front-rear direction can be changed. In this embodiment 3, an electric hydraulic cylinder is used as the connecting cylinder 17, but a hydraulic cylinder, electric cylinder, etc. may also be used. Power is transmitted between the power shaft 14 and the mower input shaft 13 via a universal joint 15. The universal joint 15 allows power to be transmitted even if the angle between the power shaft 14 and the mower input shaft 13 changes due to a change in the inclination angle of the rear frame 11a and the front frame 11b.

[0039] [Posture adjustment] In this third embodiment, the tilt of the grass trimmer C in the front-rear direction that occurs when the grass trimmer C is raised and lowered by the three-point linkage mechanism is detected by the work section tilt detection means 8, and the connecting cylinder 17 of the mounting section 1 is extended or retracted to adjust to an appropriate tilt. In this third embodiment, the posture adjustment means for the work section 4 includes a work section tilt detection means 8 and a connecting cylinder 17. Similar to Embodiment 2, as the three-point linkage mechanism is lowered, the rear gauge roller 47 can make contact with the ground regardless of the inclination of the work section 4 in the front-rear direction, and the lowering of the three-point linkage mechanism is stopped when the rear gauge roller 47 makes contact with the ground. When the descent of the three-point linkage mechanism is stopped, the front gauge wheel 48 of the brush cutter C is also in contact with the ground, and the vertical position of the front gauge wheel 48 in this state, that is, the tilt angle of the work section 4 in the front-rear direction, can be detected by the work section tilt detection means 8. Similar to Embodiment 2, the extension and retraction of the connecting cylinder 17 is controlled based on the detection signal from the front gauge wheel detector 81. In this third embodiment, as in the second embodiment, the tilt of the brush cutter C in the front-rear direction is adjusted to an appropriate tilt position as described above. This maintains a predetermined appropriate gap between the front cover 42 of the work section 4 and the work surface, preventing flying stones and the like from being scattered in front of the work section 4 if the gap becomes too large, preventing the front cover 42 from touching the work surface if the gap becomes too small, and further preventing wear caused by the brush cutter blade scraping the work surface due to the work section 4 tilting forward.

[0040] [Modified example 1 of the work section tilt detection means 8] In Embodiments 2 and 3, a work section tilt detection means 8 having a front gauge wheel 48, a front gauge wheel support arm 49b, and a front gauge wheel detector 81 is used, but a work section tilt detection means 8 with other configurations can also be used. Figure 7 is a view from the left of the working section 4 and its vicinity of the lawnmower D of Modified Example 1. In Embodiments 2 and 3, the front gauge wheels 48L and 48R are pivotally supported by front gauge wheel support parts 48L1 and 48R1 which are supported vertically by front gauge wheel support arms 49bL and 49bR. However, in this modified example, the front gauge wheels 48L and 48R are pivotally supported by front gauge wheel support parts 48L1 and 48R1 which are supported rotatably by front gauge wheel support arms 49bL and 49bR. The front gauge wheel support arms 49b are attached to the left and right side plates 44 of the work section 4 so as to be tilted downwards towards the front. The front gauge wheel support sections 48L1 and 48R1 are attached to the front ends of the front gauge wheel support arms 49bL and 49bR so as to be angled downwards toward the rear. The front gauge wheels 48L and 48R are rotatably supported at the rear ends of the front gauge wheel support sections 48L1 and 48R1.

[0041] A biasing means S is interposed between the rear ends of the front gauge wheel support sections 48L1 and 48R1 and the rear ends of the front gauge wheel support arms 49bL and 49bR to bias the front gauge wheels 48L and 48R to swing downward. In this embodiment, the biasing means S is composed of a compression coil spring, but it is not limited to this as long as it can bias the front gauge wheels 48L and 48R to swing downward. It is also possible to use a torsion coil spring instead of a compression coil spring, or to use other known biasing means. The angle between the front gauge wheel support arms 49bL and 49bR and the front gauge wheel support sections 48L1 and 48R1 is detected by the front gauge wheel detector 81. As the three-point linkage mechanism is lowered, the rear gauge roller 47 can make contact with the ground regardless of the inclination of the work section 4 in the front-rear direction, and the lowering of the three-point linkage mechanism is stopped when the rear gauge roller 47 makes contact with the ground. When the descent of the three-point linkage mechanism is stopped, the front gauge wheel 48 of the brush cutter B is also in contact with the ground, and the tilt angle of the work section 4 in the front-rear direction in this state can be detected by the work section tilt detection means 8. In this modified example 1, the front gauge wheel support arms 49bL and 49bR are attached to the side plate 44, but they can also be attached to the hitch frame 11.

[0042] [Modified example 2 of the work section tilt detection means 8] Figure 8 shows the work section tilt detection means 8 of the modified example 2, where (a) is a view from the right of the brush cutter, (b) is a view from above (partial cross-section), (c) is a view from the left of the brush cutter, and (d) is a view from the rear of the brush cutter (partial cross-section). In this modified example 2, the work section tilt detection means 8 is attached to the right side of the hitch frame 11 of the mounting section 1. The work section tilt detection means 8 may also be attached to the left side of the hitch frame 11, or to any other location on the hitch frame 11 or the work section 4. In Embodiments 2, 3, and Modification 1, the inclination angle of the work section 4 is detected using the front gauge wheel 48, but this Modification 2 differs in that it detects the inclination angle of the brush cutter (work section 4) without using the gauge wheel. The work section tilt detection means 8 includes an angle sensor 82 and an arc-shaped elongated hole H provided in the hitch frame 11.

[0043] The angle sensor 82, like the front gauge wheel detector 81, has an angle sensor body 82a and an angle detection arm 82b, and the angle sensor body 82a is attached to a mounting piece 111 which is attached to the hitch frame 11. The angle detection arm 82b is shaped so that its tip widens, and it functions as a weight. A guide pin 82c is formed at the tip of the angle detection arm 82b and is fitted into an elongated hole H provided in the hitch frame 11. The angle of the angle detection arm 82b is detected by the angle sensor body 82a. As the three-point linkage mechanism is lowered, the rear gauge roller 47 can make contact with the ground regardless of the inclination of the work section 4 in the front-rear direction, and the lowering of the three-point linkage mechanism is stopped when the rear gauge roller 47 makes contact with the ground. The tilt angle of the work unit 4 (grass trimmer) in the front-to-back direction when the descent of the three-point linkage mechanism is stopped can be detected by the work unit tilt detection means 8.

[0044] [Modified example 3 of the work section tilt detection means 8] Embodiments 1, 2, 3, and Modifications 1 and 2 calculate the front and rear tilt angles of the lawnmower using sensors that detect angles, such as potentiometers. However, it is also possible to use sensors that directly detect the front and rear tilt angles of the lawnmower, such as tilt sensors that directly detect the tilt angle from the horizontal. These tilt sensors are installed so as to detect the tilt angle from the horizontal in the front and rear direction. The tilt sensor can be installed, for example, inside the control box that houses the lawnmower control device.

[0045] As described above, Embodiments 1, 2, 3, Modification 1, 2, and 3 of the present invention have been described in detail with reference to the drawings. However, the specific configuration is not limited to these embodiments and modifications, and any design changes, etc., that do not depart from the gist of the present invention are also included. Furthermore, the above-mentioned embodiments and modifications can be combined by utilizing each other's technologies, as long as there are no particular contradictions or problems in their purpose and configuration. [Explanation of Symbols]

[0046] A, B, C, D Lawn Mower 1. Mounting part 11 Hitch Frame 11a Rear frame 11b Front frame 111 Mounting piece 12 Gearbox 13. Lawn mower input shaft 14 Power shaft 15 Universal Joint 16 rotational axes 17. Connecting Cylinder 2. Offset mechanism 21 Offset Frame 22 Link Rods 23 Support frame 24 Offset Cylinder 3 Power transmission section 31 Front gear case 4. Work Section 41 Working rotor 41a Rotation axis 42 Front cover 43 Shield Cover 431 Tilt cylinder mounting section 44 Side panels 44a Pivot 44b Rotation fulcrum 45 Rear gear case 46. ​​Cutting blade drive unit 47 Rear gauge roller 47a Scraper 48 Front gauge wheel 48L left front gauge wheel 48R Right front gauge wheel 48C Center front gauge wheel 48L1, 48R1, 48C1 Front gauge wheel support 49 gauge support arm 491 Front gauge wheel support frame 49a Rear gauge roller support arm 49b Front gauge wheel support arm 5. Tilt mechanism 51 Support Arm 52 Tilt Cylinder 53. Rotary shaft bracket 6. Three-point linkage mechanism 61 Top Links 62 Lower Link 7 Auto hitch 8. Working section tilt detection means 81 Front gauge wheel detector 81a Front gauge wheel detector body 81b Front gauge wheel detection arm 82 Angle Sensor 82a Angle sensor body 82b Angle detection arm 82c Guide pin H long hole S biasing means

Claims

1. A mounting part that can be connected to a coupling mechanism that allows the vehicle body to move up and down, An agricultural machine comprising a work unit that receives power from the aforementioned vehicle body and performs predetermined tasks, An agricultural implement characterized by having posture adjustment means for adjusting the inclination of the work part in the front-rear direction so that the inclination of the work part in the front-rear direction with respect to the work surface is a predetermined inclination.

2. The work section has a cover that covers the front of the work section, The agricultural implement according to claim 1, characterized in that the posture adjustment means adjusts the inclined posture of the cover.

3. The posture adjustment means includes a detection means for detecting the front and rear tilt angles of the work section. The agricultural machine according to claim 1, characterized in that it transmits a detected value detected by the detection means, or a control signal for controlling the vertical movement of the coupling mechanism calculated based on the detected value, to the vehicle body.

4. The aforementioned mounting section has a front frame and a rear frame. The aforementioned front frame is connectable to the aforementioned connecting mechanism, The rear frame supports the work section and is connected to the front frame so as to be able to adjust its tilt position in the front-rear direction relative to the front frame. The agricultural machine according to claim 1, wherein the posture adjustment means has a detection means for detecting the inclination state and adjusts the front-to-rear inclination posture of the rear frame relative to the front frame.

5. An offset mechanism connects the mounting portion and the working portion, and moves the working portion in the left-right direction. An agricultural implement according to any one of claims 1 to 4, characterized in that it comprises a tilt mechanism that connects the offset mechanism and the work section and rotates the work section in the vertical direction.

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