Agricultural implement

Abstract

To provide an agricultural implement in which a control mechanism for adjustment of ground leveling is appropriately provided so as not to damage the appearance and not to hinder visual check.SOLUTION: An agricultural implement includes: a machine frame having a transmission part which obtain a power from a drive body on which an operator is seated; a tiller part for tilling with the power transmitted from the transmission part; a leveling body which can change a posture on a rear side of the tiller part; and an actuator which changes a posture of the leveling body and is provided at a position not visible from the operator. The actuator includes a cylinder, and a rod which is movable frontward and rearward with respect to the cylinder. The rod during operation of the actuator does not hinder the view of the operator. Furthermore, the actuator is positioned on a rear side of the transmission part. Furthermore, the actuator does not project on a rear side from a rear end of the cover body. Furthermore, the machine body includes an installation part having a top mast, the actuator not projecting above the top mast.SELECTED DRAWING: Figure 5A

Description

[Technical Field]

[0001] The present invention relates to an agricultural work machine, and more particularly to an agricultural work machine for breaking up and leveling mud and clods in a field. [Background technology]

[0002] Known examples of agricultural implements that are attached to a traveling body and that till, break, and level the soil include those described in Patent Documents 1 and 2. According to these documents, the implements have a drive unit that can regulate and release the position of the leveling plate or leveling plate. The drive unit is a mechanism that includes actuators such as cylinders and motors, which are located above or to the side of the top mast, which is located above the transmission unit. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2008-136427 [Patent Document 2] Japanese Patent Application Laid-Open No. 2014-75987 Summary of the Invention [Problem to be solved by the invention]

[0004] When using the agricultural implements described in Patent Documents 1 and 2, a worker aboard the traveling body may directly visually check the field scene over the agricultural implement to confirm the results of the work performed by the agricultural implement from a seated position. Alternatively, a worker aboard the traveling body may visually check the leveling board and leveling unit located at the rear of the agricultural implement, which perform the final process of the agricultural implement, to ensure that they are operating properly. However, the agricultural implements described in Patent Documents 1 and 2 have a drive unit located near the top mast and transmission, making it impossible to visually check the field after work, the leveling board, and other items over the drive unit. It could be said that the drive unit itself obstructs visual inspection. Even if the drive unit is located in a location that does not obstruct visual inspection, careless placement could result in a lack of cohesion between the various components that make up the agricultural implement, potentially damaging its aesthetic appearance. Furthermore, it is also possible to place the drive unit between the gearbox and the cover that covers the tilling section, but if there is not enough space for placement, there is a problem that it cannot be placed efficiently.

[0005] Therefore, the present invention has been made with the above-mentioned problems in mind, and aims to provide an agricultural work machine in which the control mechanism for adjusting the ground leveling body is appropriately positioned so as not to spoil the aesthetic appearance or interfere with visual confirmation. [Means for solving the problem]

[0006] In order to solve the above problems, one aspect of the present invention is an agricultural work machine that includes a machine frame having a transmission that obtains power from a running body on which an operator rides, a tilling unit that tills using power transmitted from the transmission, a soil leveling body whose posture can be changed behind the tilling unit, and an actuator that changes the posture of the soil leveling body and is located in a position that is not visible to the operator. [Effects of the Invention]

[0007] The configuration of the present invention makes it possible to provide an agricultural work machine in which the control mechanism for adjusting the soil leveling body is appropriately positioned so as not to impair the aesthetic appearance or interfere with visual confirmation. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a front view showing an embodiment of an agricultural work machine according to the present invention. [Figure 2] FIG. 2 is a right side view of FIG. [Figure 3A] FIG. 2 is an enlarged plan view of part A in FIG. [Figure 3B] FIG. 3B is a front view of the main part of FIG. 3A. [Figure 3C] FIG. [Figure 4] 2 is an enlarged partial cross-sectional plan view of part B in FIG. 1. [Figure 5A] 2 is an enlarged side view of part A in FIG. 1, showing the state of the pressure regulating rod when the swing arm is located in the regulated range. [Figure 5B] 2 is an enlarged side view of part A in FIG. 1, showing the state of the pressure adjustment rod when the swing arm is positioned at a first position maintenance point in the position maintenance section. [Figure 5C] 2 is an enlarged side view of part A in FIG. 1, showing the swing arm positioned at the first attitude maintenance point in the attitude maintenance section and the soil leveling body in the plowing operation. [Figure 5D] 2 is an enlarged side view of part A in FIG. 1, showing the state of the pressure adjustment rod when the swing arm is located at a second attitude maintenance point in the attitude maintenance section. [Figure 5E] 1. This is an enlarged side view of part A in FIG. 1, showing the swing arm positioned at the second posture maintaining point in the posture maintaining section, and the soil leveling body in the plowing operation. [Figure 6A] 2 is an enlarged cross-sectional side view of part B in FIG. 1, showing the state of the pressure adjustment rod when the swing arm is located in the regulated range. [Figure 6B] 1, showing the state of the pressure adjustment rod when the swing arm is positioned at a first position maintenance point in the position maintenance section. FIG. [Figure 6C] 2 is an enlarged cross-sectional side view of part B in FIG. 1, showing the state when the swing arm is positioned at the first attitude maintenance point in the attitude maintenance section and the soil leveling body is performing plowing work. [Figure 6D]1, showing the state of the pressure adjustment rod when the swing arm is positioned at a second position maintenance point in the position maintenance section. FIG. [Figure 6E] This is an enlarged plan view of a part of the cross section of part B in Figure 1, showing the state of the pressure adjustment rod when the swing arm is positioned at the second attitude maintenance point in the attitude maintenance section, and also showing the state during the plowing operation of the soil leveling body. [Figure 7A] 1, showing the state of the cam link when the swing arm is located in the restricted range. FIG. [Figure 7B] 1, showing the state of the cam link when the swing arm is positioned at the first position maintenance point in the position maintenance section. FIG. [Figure 7C] 1, showing the state of the cam link when the swing arm is positioned at a second position maintenance point in the position maintenance section. FIG. [Figure 8] 10 is a diagram showing the interlocking relationship between the link support member, the first link, the swing arm, the operating arm, and the interlocking member. FIG. [Figure 9] 10 is a diagram showing the interlocking relationship between a first link, a swing arm, an operating arm, and a linking member. FIG. [Figure 10] FIG. 2 is a front view of the agricultural implement of FIG. 1 in a folded state. [Figure 11] FIG. 11 is a side view of FIG. [Figure 12] 1. FIG. 4 is an enlarged side view showing a modified example of the first link of FIG. BEST MODE FOR CARRYING OUT THE INVENTION

[0009] Next, the agricultural work machine according to the present invention, which illustrates an embodiment, will be described in more detail. For convenience, parts that perform the same function will be assigned the same reference numerals, and their description may be omitted. In the front view shown in Figure 1 etc., the left side shown in the figure will be expressed as the left side in the direction of travel, and the right side shown in the figure will be expressed as the right side in the direction of travel. Furthermore, in the right side side view shown in Figure 2 etc., the left side shown in the figure will be expressed as the front side in the direction of travel, and the right side shown in the figure will be expressed as the rear side in the direction of travel. In the front view shown in Figure 1 etc. and the side view shown in Figure 2 etc., the upper side shown in the figure will be expressed as the upper side relative to the machine body, and the lower side shown in the figure will be expressed as the lower side relative to the machine body.

[0010] As shown in Figures 1 to 11, the agricultural work machine 1 of the present invention comprises a central work body 2, side work bodies 3, a posture control unit 17, and a pressure adjustment unit 51, and is attached to the rear of a traveling machine body such as a tractor and performs work by moving forward. Each work body 2, 3 has a machine frame 4 that supports the machine body, a tilling unit 11 located below the machine frame 4, a cover body 35 that covers the upper part of the tilling unit 11, soil leveling bodies 31, 33 that can rotate up and down at the rear end of the cover body 35, and a posture control unit 17 and pressure adjustment unit 51 that fix and release the posture of the soil leveling bodies 31, 33. The posture control unit 17 and pressure adjustment unit 51 are operated by remote control. The machine frame 4 has a mounting section including top pins 8 and lower pins 9 that are attached to the traveling body (not shown), a transmission section 89 that receives power from the traveling body via an input shaft 91 and changes speed, and a pipe frame 85 that supports the mounting section and transmission section 89 and extends to the left and right from the transmission section 89. In addition to the pipe frame 85, the machine frame 4 may have a second pipe frame 93 that is located in front of the transmission section 89 and secures support members 99 (described below) to each other. Although the present invention can be implemented without the second pipe frame 93, the embodiment will be described as including the second pipe frame 93. The cover body 35 covers the entire upper part of the tilling section 11 from the front to the rear and prevents mud from flying.

[0011] The side working bodies 3 are arranged on both sides of the central working body 2, which is arranged in a direction perpendicular to the traveling direction, i.e., on the left and right sides of the central working body 2 as shown in FIG. 1. The central working body 2 and side working bodies 3 are attached to a three-point linkage device (not shown) of the traveling machine body by the top pin 8 and lower pin of the top mast 7. The cultivating units 11 of the central working bodies 2 and side working bodies 3 are rotatably attached below the machine frame 4. Note that the present invention can be implemented without the side working body 3 and with only the central working body 2, but the embodiments will be described assuming that the side working body 3 is present.

[0012] The tilling unit 11 is arranged in multiples at intervals in the axial direction, and each has multiple tines 15 arranged in multiples in the circumferential direction of the rotor shaft 13. The tilling unit 11 is rotatably supported by a support member 99 arranged at the end of the pipe frame 85, and a chain case 95 attached to the support member 99 on the left side of the central working body 2 transmits rotational power output from the transmission unit 89 to the rotor shaft 13, driving it to rotate. The tilling unit 11 breaks up mud and soil clods with the rotating tines 15. In actual operation, the tilling unit 11 breaks up the soil as it moves forward. Leveling bodies 31, 33 are provided behind the tilling unit 11 via a posture control unit 17.

[0013] A cover body 35 is provided to cover the upper part of the tilling unit 11. A vertically rotatable soil leveling body is provided at the rear end of the cover body 35. The soil leveling body is composed of a first soil leveling body 31 and a second soil leveling body 33. The first soil leveling body 31 is provided at the rear end of the cover body 35 so as to be vertically rotatable, and the second soil leveling body 33 is provided at the rear end of the first soil leveling body 31 so as to be vertically rotatable. The first soil leveling body 31 and the second soil leveling body 33 each press down on the crushed mud from above, thereby leveling the crushed mud. The first soil leveling body 31 rotates vertically integrally with the holding plate 32 via a pivot fulcrum 31a provided at the rear end of the cover body 35. In this embodiment, the cover body 35 and the transmission unit 89 are positioned so that the cover body 35 is located below and adjacent to the transmission unit 89, leaving no space between them for arranging other components. In the description, the first leveling body 31 may be referred to as the leveling body 31, and the second leveling body may be referred to as the leveling body 33.

[0014] The holding plates 32 are a pair of plate members erected on the upper surface of the first soil leveling body 31, with a holding member 69 loosely fitted to the top. The holding member 69 is rotatable about a left-right axis relative to the direction of travel. Multiple rotation fulcrums 31a are provided in the width direction of the first soil leveling body 31. The postures of the first soil leveling body 31 and the second soil leveling body 33 can be fixed and released by the posture control unit 17. The fixed posture state is also referred to as the pile-up state, and the released posture state is also referred to as the puddling state. The second soil leveling body 33, which rotates at the rear end of the first soil leveling body 31, is rotatable in the vertical direction around a rotation fulcrum 33a provided at the rear end of the first soil leveling body 31. In the embodiment, one posture control unit 17 is provided on each of the central working body 2 and the side working body 3, but it is sufficient to provide one or more posture control units for the agricultural work machine 1 regardless of whether or not a side working body 3 is installed.

[0015] The posture control unit 17 is made up of a first link 18, a second link 19, and a swing arm 25, and controls the posture of each second leveling body 33 by controlling the posture of each first link 18 of the central working body 2 and the side working bodies 3 separately from the operation of the tilling unit 11. As shown in Figures 5A to 5E, the front end of the first link 18, which is the left end in the figure, is rotatably connected to the machine frame 4 by a rotation fulcrum 18a, and the rear end, which is the right end in the figure, is rotatably connected to the second link 19 up and down in the vertical direction. The upper end of the second link 19 is rotatably connected to the first link 18, and the lower end is rotatably connected to the top of the second leveling body 33.

[0016] A guide portion 21 is provided on the underside of the first link 18. The guide portion 21 includes a restriction hole 23, which is a hook-shaped hole provided on the underside of the first link 18, and a posture maintaining portion 24, which is provided in a vertical concave arc shape continuous with the restriction hole 23. A swing arm 25 is provided below the first link 18 and is rotatable about a pivot point 25a. An engagement portion 27, which slides on the guide portion 21, is provided at the upper end of the swing arm 25. A contact portion 26 protrudes near the engagement portion 27 in a direction perpendicular to the traveling direction (to the left of the swing arm in FIG. 5A). In this embodiment, the contact portion 26 protrudes in both left and right directions perpendicular to the traveling direction of the swing arm 25. The contact portion 26 is also referred to as a cam engagement portion 41. The contact portion 26 is the portion that abuts against an operating arm 53 (described later), and the cam engagement portion 41 is the portion that engages with a cam link 37 (described later). The contact portion 26 and the cam engaging portion 41 are provided coaxially.

[0017] When the engaging portion 27 engages with the restricting hole 23, the rotation of the first link 18 is restricted, forming a restricted range C in which the rotation of each of the first leveling body 31 and the second leveling body 33 is fixed. On the other hand, when the engaging portion 27 engages with the posture maintaining portion 24, the restriction on the upward rotation of the first leveling body 31 and the second leveling body 33 is released, forming a posture maintaining section R in which the posture of the first link 18 does not change.

[0018] When the swing arm 25 rotates, the engaging portion 27 moves from the restricted area C toward the position maintenance section R. It reaches the first position maintenance point 24a, which is the starting point of the position maintenance section R and is closer to the restricted area C. It then reaches the second position maintenance point 24b, which is the end point of the position maintenance section R. The center of the arc of the position maintenance portion 24 coincides with the center of rotation of the swing arm 25. Therefore, whether the engaging portion 27 is located at the first position maintenance point 24a or the second position maintenance point 24b, the effect of the restriction release is essentially the same. In other words, as long as the engaging portion 27 is located in the position maintenance section R, the position of the first link 18 does not change, and the second leveling body 33 does not rotate downward, and the lower end, which is the operating end, does not move. This will be discussed later. The operator decides whether to move the swing arm 25 from the second position maintenance point 24b to the first position maintenance point 24a based on the unevenness of the field and the degree of soil crushing.

[0019] An actuator 43 is provided which has a cylinder 43a which makes it possible to change the engagement position between the engagement portion 27 and the guide portion 21 at any position in the posture maintaining section R. The actuator 43 has a rod 43b which can move forward and backward. The actuator 43 is provided with a sensor which detects the stroke amount of the rod 43b which extends and retracts. The source of operation for the actuator 43 is electric power in this embodiment, but it may also be hydraulic.

[0020] 5A to 6E, the cylinder 43a is provided with a sensor that detects the maximum stroke amount of the rod 43b at the extended position H, the minimum stroke amount of the rod 43b at the retracted position L, and an intermediate position M that is the intermediate point between the extended and retracted positions. This sensor also detects the restricted range C, the first posture maintenance point 24a that is the restriction release start point of the posture maintenance section R, and the second posture maintenance point 24b that is the restriction release end point.

[0021] A cam link 37 is provided coaxially with the pivot point 18a of the first link 18. The cam link 37 is a plate-like member that is rotatable about an axis parallel to the first link 18, and has an arc-shaped cam hole 39 on one end. The pivot point of the cam link 37 in this embodiment is provided coaxially with the first link 18. The cam hole 39 is an elongated hole formed in an arc, and a cam engagement portion 41 that is provided from the swing arm 25 toward the cam hole 39 is disposed within the cam hole 39. The cam engagement portion 41 is movable within the cam hole 39. The center of the arc of the arc-shaped cam hole 39 is positioned away from the pivot center of the cam link 37, and rotation of the cam link 37 causes the cam engagement portion 41 to move within the cam hole 39, causing the swing arm 25 to swing around the pivot point 25a. As the cam link 37 rotates, the cam engagement portion 41 moves within the cam hole 39, thereby rotating the swing arm 25. In the explanation, the cam link 37 is shown as being disposed on the right side of the swing arm 25 in the direction of travel in order to facilitate understanding of the structure, but it may be disposed on the left side of the swing arm 25 in the direction of travel, or on both the left and right sides of the swing arm 25 in the direction of travel.

[0022] The other end of the cam link 37 is connected to the end of the rod 43b of the actuator 43. The end of the cylinder 43a of the actuator 43, opposite the end of the rod 43b, is connected to an attachment part 7a provided at the rear end, in the traveling direction, of the top mast 7, which is an attachment part for the traveling machine body. The actuator 43 is provided so as to be located near the rear of the top mast 7 in the traveling direction and near the rear of the transmission unit 89 in the traveling direction. The actuator 43 drives and rotates the cam link 37 as the rod 43b advances and retreats from the lower end side of the cylinder 43a. With the above-mentioned configuration, the swing arm 25 and cam link 37, and the cam link 37 and swing arm 25 are each connected, and as a result, the swing arm 25 can swing when driven by the actuator 43 via the cam link 37.

[0023] 7A to 7C, when the rod 43b of the actuator 43 moves downward, the cam link 37 rotates so that the cam hole 39 moves upward, and when the rod 43b of the actuator 43 moves upward, the cam link 37 rotates so that the cam hole 39 moves downward. Specifically, when the end of the rod 43b of the actuator 43 moves downward to its maximum protrusion, the cam link 37 rotates so that the cam hole 39 moves upward, causing the swing link 25 to reach the restriction range C via the cam engagement portion 41. When the end of the rod 43b moves upward to its minimum protrusion, the cam link 37 rotates so that the cam hole 39 moves downward, causing the swing link 25 to reach the second position-maintaining point 24b via the cam engagement portion 41. When the protrusion of the end of the rod 43b reaches approximately the middle, the cam link 37 rotates so that the cam hole 39 moves downward, causing the swing link 25 to reach the first position-maintaining point 24b via the cam engagement portion 41. In other words, when the actuator 43 is activated and the oscillating arm 25 moves upward, the oscillating arm 25 is rotated so that the engagement portion 27 moves from the posture maintaining portion 24 toward the regulating hole 23, and when the oscillating arm 25 moves downward, the oscillating arm 25 is rotated so that the engagement portion 27 moves from the regulating hole 23 toward the posture maintaining portion 24.

[0024] The actuator 43 is disposed so that the rod 43b moves forward and backward in the vertical direction relative to the machine body. In other words, the actuator 43 is disposed so that the rod moves forward and backward in the vertical direction relative to the wooden frame. The actuator 43 is configured so that it does not protrude upward from the top surface of the top mast 7 even when the rod 43b moves forward and backward. More preferably, as illustrated in the drawings, the actuator 43 is configured so that it does not protrude upward from the upper end of the rear end of the top mast 7 even when the rod 43b moves forward and backward. Furthermore, the width of the actuator 43 in the direction of travel is narrower than the width of the top mast 7 in the direction of travel. The width of the transmission unit 89 located below the top mast 7 in the direction of travel is wider than the width of the top mast 7, and therefore can also be said to be wider than the width of the actuator 43. In other words, the actuator 43 is disposed so that, when viewed from the front, the rod 43b fits within the width of the top mast 7 and the transmission unit 89 regardless of whether it moves forward or backward.

[0025] Although the actuator 43 is located behind the top mast 7 and the speed change unit 89, it does not protrude rearward in the direction of travel from the rear end of the cover body 35. Furthermore, even when the rod 43b is advanced or retracted relative to the cylinder 43a, it does not protrude rearward in the direction of travel from the rear end of the cover body 35, nor does it protrude above the top mast 7. In this embodiment, the center of the left-right width of the central working body 2 in the direction of travel is the speed change unit 89 and the top mast 7. With regard to the central working body 2, by arranging the actuator 43 as described above, the first link 18 and the second link 19 can be positioned in the center of the second ground leveling body 33, which is behind the speed change unit 89 and the top mast 7. Therefore, the first link 18 and the second link 19 can bear the load of the second ground leveling body 33 at the center of the second ground leveling body 33, and the second ground leveling body 33 is less likely to be subjected to a load in a direction that would twist unevenly left and right.

[0026] Furthermore, the actuator 43 does not extend beyond the vertical, horizontal, or lateral projection area of ​​the mounting section having the top mast 7 and the transmission section 89 when viewed from the forward or reverse side in the direction of travel. Therefore, the actuator 43 of the posture control section 17 is positioned so that it cannot be seen by an operator riding on the traveling machine body when looking behind where the agricultural work machine 1 is located. Therefore, when the operator views the agricultural work machine 1 and the area behind the agricultural work machine 1, the actuator 43, which is the drive device for the posture control section 17, does not obstruct the operator's view.

[0027] Moreover, because the rotation fulcrum of the cam link 37 is coaxial with the first link 18, the actuator 43, cam link 37, first link 18, and second link 19 can be arranged side by side in the fore-and-aft direction, and their fore-and-aft lengths can be further shortened. That is, even though the actuator 43 is located rearward of the top mast 7 and transmission unit 89 of the mounting portion in the direction of travel and forward of the rear end of the cover body 35, the swing link can be swung to restrict or release the restriction on the rotation of the first link. Furthermore, even when the rod 43b is moved up and down, it does not protrude beyond the projected area of ​​the top mast 7 and transmission unit 89 in the direction of travel. That is, even when the swing arm 25 is rotated, the actuator 43 is not visible to the operator aboard the traveling machine body, and does not obstruct their view.

[0028] In the embodiment, the actuator 43 is configured so that it does not protrude beyond the projected area of ​​the top mast 7 and the transmission unit 89 in the traveling direction even when the rod 43b is advanced or retracted, but it is sufficient that the cylinder 43a does not protrude upward or to the left or right of the projected area of ​​the top mast 7 and the transmission unit 89 in the traveling direction. In other words, as long as at least the cylinder 43a is located within the projected area of ​​the top mast 7 and the transmission unit 89 in the traveling direction, an operator positioned in front of and above the agricultural working machine will not be able to see the actuator 43, including the rod 43a, even if the lower end of the rod 43a protrudes from below the transmission unit 89 as a result of the rod 43a being advanced or retracted. Therefore, the rod 43a does not obstruct the operator's view when it is advanced or retracted.

[0029] Furthermore, because the swing arm 25 is configured to be swung by the actuator 43 via the cam link 37, it is configured so that the first link 18 can swing about the rotation fulcrum 18a of the first link as a fulcrum while being as close as possible to the cover body 35. When the central working body 2 and the side working bodies 3 are in the unfolded state, a space S free of any components can be secured above the first link 18 and behind the actuator 43 in the direction of travel. When the side working body 3 is folded above the central working body 2 and put into a stored state, the space S of the central working body 2 and the space S of the side working body 3 can be prevented from interfering with the various structures located above the cover body 35 and the ground leveling bodies 31, 33. In other words, even when the side working body 3 is put into the stored state, the posture control units 17 of the central working body 2 and the side working bodies 3 do not interfere with other components, so that smooth transition between the unfolded state and the stored state can be achieved.

[0030] Furthermore, a link arm 45 can be provided on the other end of the cam link 37. The link arm 45 is connected to a gauge 47 that is rotatably mounted on the top mast 7, which is the attachment point for the traveling machine body. The gauge 47 is rotatably mounted on the top mast 7, and its swinging movement can be seen by an operator on board the traveling machine body. A scale plate 49 is provided near the gauge 47, and the position to which the gauge 47 has swung can be read.

[0031] The link arm 45 is rotatable relative to the cam link 37, and a rotatable gauge 47 is provided at the tip of the link arm 45. The current position of the cam engagement portion 41 in the guide portion 21 (rotation fulcrum 25a of the swing arm) can be read from the amount of swing of the gauge 47. In this embodiment, the middle portion of the link arm 45 is provided at the rear end of the top mast 7, penetrating the right side surface in the traveling direction, preventing the link arm 45 from being positioned so as to protrude to the side of the top mast 7 or the transmission unit 89. This minimizes obstruction to the operator's field of vision.

[0032] The posture control unit 17 is positioned immediately behind the top mast 7 and the transmission unit 89, yet still allows the first leveling plate 31 and the second leveling plate 33 to operate smoothly. More specifically, the actuator 43, which serves as the drive device, is positioned immediately behind the top mast 7 and the transmission unit 89, and the cam link 37, swing link 25, and first link 18, which are located behind the actuator 43, are positioned as close as possible to the cover body 35, yet still allows the first leveling plate 31 and the second leveling plate 33 to operate. By enabling the above-described positioning, the posture control unit 17 makes components such as the top mast 7 and the transmission unit 89 appear integrated, improving the overall aesthetic appearance of the agricultural work machine 1. The improved aesthetic appearance also increases the satisfaction of the owner of the agricultural work machine 1, allowing the worker to work comfortably. Furthermore, because a space S is secured above the first link 18 and behind the actuator 43, this space S does not obstruct the view of the worker aboard the traveling machine body. Furthermore, the space S prevents the two sides from interfering with each other even when the side working structures 3 are stored. Also, even when the side working structures 3 are folded above the central working structure 2, the space S allows the side working structures 3 to be positioned in this space S, so the overall vertical height when folded and stored can be reduced.

[0033] Reference numeral 51 denotes a pressure adjusting unit that controls pressure, and in this embodiment, it is provided in two locations on both sides of the central working body 2, and one location on each side of the left and right side working bodies 3. There are no restrictions on the location or number of pressure adjusting units 51; for example, it is possible to provide one on the central working body 2 and none on the left and right side working bodies 3. The pressure adjusting unit 51 consists of a rotatable operating arm 53 that links the swinging arm 25, a pressure adjusting rod 55 that adjusts the biasing force of the soil leveling body 33 toward the field, and a linking member 57 that inputs and outputs the amount of rotation of the operating arm 53.

[0034] The operating arm 53 is rotatably mounted on an axis parallel to the swing arm 25 above the tilling unit 11 and the cover body 35. One end of the operating arm 53 is provided with a receiving portion 59 against which the abutment portion 26 provided on the swing arm 25 abuts. The operating arm 53 can be rotated when the abutment portion 26 presses the receiving portion 59 when the swing arm 25 is rotated in one direction. In other words, the operating arm 53 is only allowed to rotate when the abutment portion 26 of the swing arm 25 is in abutment with the receiving portion 59; when the swing arm 25 is rotated in the other direction, the operating arm 53 does not rotate. 53a is the rotation fulcrum of the operating arm 53.

[0035] The operating arm 53 is provided with a rotation limiting portion 100a that limits the range of rotation, and the operating arm 53 rotates within the rotation range determined by this rotation limiting portion 100a. The rotation limiting portion 100a causes the operating arm 53 to abut against the swing arm 25 within a range that is limited by the total rotation amount of the swing arm 25. Within a range where the abutment portion 26 and the receiving portion 59 cannot abut, only the swing arm 25 rotates. The operating arm 53 and the swing arm 25 are provided so that the receiving portion 59 can move via the rotation limiting portion 100a (described below) and so that the abutment portion 26 can pass through the opening 100b. Specifically, in the guide portion 21 that includes the restricted range C and the posture maintaining section R provided on the first link 18, the abutment portion 26 and the receiving portion 59 can abut against each other when the engagement portion 27 is within the posture maintaining section R. That is, as shown in FIGS. 5B to 5E, when the swing arm 25 is in the posture maintaining section R, the operating arm 53 is operated by the rotation of the swing arm 25.

[0036] The other end of the operating arm 53 is connected to one end of a linking member 57. The linking member 57 transmits the rotation of the operating arm 53 to other members, and also transmits rotational force from other members to the operating arm 53. The linking member 57 is an input / output member that can output the rotation of the operating arm 53 and input force to rotate the operating arm 53. In this embodiment, the linking member 57 uses a wire or cable, but it may also be a link device formed by connecting and combining multiple rods or the like.

[0037] The pressure regulating rod 55 comprises a rod body 61, a rotation restricting member 67 that holds the rod body 61 and has a first elongated hole 63 and a second elongated hole 65 formed in the axial direction, a holding member 69 that moves within the first elongated hole 63, a restricting body 71 that moves within the second elongated hole 65, a first elastic body 73 that is provided between the restricting body 71 and the holding member 69 and urges the soil leveling bodies 31, 33 toward the field, and a second elastic body 75 that is provided between the holding member 69 and a pin 76a at the tip of the rod body 61 and urges the soil leveling bodies 31, 33 away from the field. The rod body 61 is suspended from above the tilling unit 11 to above the soil leveling bodies 31, 33. 76b is a pin provided at the base end of the rod body 61 that secures the rod body 61 within the rotation restricting member 67. 69a is a protruding portion of the holding member 69. The rod body 61 and the rotation restricting member 67 are provided integrally.

[0038] The base end of the pressure regulating rod 55 is rotatably supported by a pivot fulcrum 87 provided on the pipe frame 85, and together with the retaining member 69, it is suspended above the tilling unit 11 and above the soil leveling body 31. The pressure regulating rod 55 slides within the insertion hole of the retaining member 69 as the soil leveling bodies 31, 33 move up and down. Note that the base end of the pressure regulating rod 55 does not have to be supported by the pipe frame 85, as long as the pivot fulcrum 87 is supported above the cover body 35. For example, the pivot fulcrum 87 may be provided on the cover body 35.

[0039] The rod body 61 is inserted into and covered by the rotation restriction member 67. The front end of the rod body 61 is fixed by a pin 76b provided at the front end of the rotation restriction member 67. The rotation restriction member 67 has a first elongated hole 63 into which a protrusion 69a of a holding member 69 is movably slidably fitted. The protrusion 69a moves within the first elongated hole 63 as the ground leveling units 31, 33 rise and fall, restricting the rotation angle of the ground leveling units 31, 33. When the ground leveling units 31, 33 rotate downward, the holding member 69 slides on the rod body 61, causing the protrusion 69a to move relatively within the first elongated hole 63 and come into contact with the rear end side of the first elongated hole 63 (Figure 6B), preventing the ground leveling units 31, 33 from rotating downward. Furthermore, when the ground leveling bodies 31, 33 rotate upward, the retaining member 69 slides on the rod body 61, causing the protrusion 69a to move relatively within the first elongated hole 63 and come into contact with the front end side of the first elongated hole 63, preventing the ground leveling bodies 31, 33 from rotating upward. Figure 6C shows the first ground leveling body 31 in the middle of rotating up and down. The protrusion 69a moves within the first elongated hole 63 as the first ground leveling body 31 rotates.

[0040] The drive source of the pressure adjusting unit 51, specifically the operating arm 53, and the drive source of the attitude control unit 17, specifically the swing arm 25, are the same as shown in Fig. 3, and are the actuators 43 in this embodiment. In addition, by changing the timing at which the biasing force of the first elastic body 73 is exerted, the biasing force for rotating the ground leveling body 31 downward can be freely changed to a desired force.

[0041] The first elastic body 73 is provided between the regulating body 71 and the holding member 69, and is biased in a direction that rotates the ground leveling bodies 31, 33 downward. When the ground leveling bodies 31, 33 are rotated upward (FIGS. 6A to 6C), the holding member 69 gradually slides toward the front end of the rod main body 61, and the distance between the holding member 69 and the regulating body 71 gradually decreases (FIGS. 6D and 6E). Then, the first elastic body 73 located between the regulating body 71 and the holding member 69 shortens, and stores a force that rotates the ground leveling bodies 31, 33 downward, and is biased to rotate downward.

[0042] When the regulating body 71 is moved toward the rotation fulcrum 87 of the pressure regulating rod 55 (to the left in the figure), the compression start position of the first elastic body 73, which has moved the ground leveling bodies 31, 33 upward, becomes higher, and the downward urging force of the ground leveling bodies 31, 33 becomes weaker. On the other hand, when the regulating body 71 is moved toward the holding member 69 of the pressure regulating rod 55 (to the right in the figure), the compression start position of the first elastic body 73, which has moved the ground leveling bodies 31, 33 upward, becomes lower, and the downward urging force of the ground leveling bodies 31, 33 becomes stronger. In other words, by moving the regulating body 71 relative to the pressure regulating rod 55, the compression start position of the first elastic body 73 can be changed, and the force that rotates the ground leveling bodies 31, 33 downward can be changed.

[0043] When the first elastic body 73 biases the soil leveling body 31, the biasing force of the first elastic body 73 can be applied to the field surface in addition to the weight of the soil leveling body 31. When the biasing force of the first elastic body 73 is increased, the uncrushed soil clods are prevented from pushing aside the soil leveling plate 31 and moving rearward, increasing the opportunity for soil to be crushed between the soil leveling bodies 31, 33 and the tilling unit 11. Furthermore, by strongly pushing against the field surface after crushing, soil leveling performance can be further improved. When the biasing force of the first elastic body 73 is weakened, the crushed soil is more likely to pass under the soil leveling plate 31 and move rearward. As a result, the soil leveling plate 31 does not press down on the mud more than necessary, preventing the soil leveling plate 31 from gouging out the field surface.

[0044] A second elastic body 75 is provided between the pin 76a, located on the rear side of the rod body 61 in the direction of travel, and the retaining member 69. As a result, when the soil leveling units 31, 33 rotate downward, the distance between the pin 76a and the retaining member 69 is shortened, and when the soil leveling units 31, 33 rotate downward, an upward biasing force is applied to the soil leveling units 31, 33. The biasing force of the second elastic body 75 is set to be weaker than the force that causes the soil leveling units 31, 33 to rotate downward due to their own weight. This ensures that the lower ends of the soil leveling units 31, 33 are reliably positioned in the direction of rotation. The second elastic body 75 facilitates upward rotation when the soil leveling units 31, 33, located at the lower end in the direction of rotation, touch the field and rotate upward. As a result, when the ground leveling bodies 31, 33 positioned at the lower end in the rotation direction are to be brought into contact with the field, the ground leveling bodies 31, 33 do not poke into the field or dig into the soil of the field.

[0045] The second elastic body 75 is biased to rotate the first soil leveling body 31 upward. When the first soil leveling body 31 is positioned at the lower end of rotation, the second elastic body 75 pushes the first soil leveling body 31 upward, so the first soil leveling body 31 easily rotates upward. The biasing force of the second elastic body 75 is set to be weaker than the load in the rotation direction due to the weight of the first soil leveling body 31 and the second soil leveling body 33, so it does not hinder the first soil leveling body 31 from being positioned at the lower end of rotation. In this way, when the first soil leveling body 31 touches down on muddy soil, the first soil leveling body 31 is easily lifted upward, and the first soil leveling body 31 and the second soil leveling body 33 do not dig or gouge the field surface. In addition, the second elastic body 75 has the effect of mitigating the impact when the first leveling body 31 reaches the lower end of rotation. When the first leveling body 31 reaches the lower end of rotation, the protruding portion 69a of the holding member 69 comes into contact with the rear end of the first elongated hole 63 (FIG. 4), restricting downward rotation of the first leveling body 31, but it is also possible to mitigate the impact of contact between the protruding portion 69a of the holding member 69 and the first elongated hole 63.

[0046] Reference numeral 77 denotes a switching arm, which moves the regulating body 71 relative to the rod main body 61 in conjunction with the rotation amount of the operating arm 53 via the linking member 57 .

[0047] A fulcrum shaft 77a facing in the left-right direction perpendicular to the direction of travel is provided above the pressure adjustment rod 55, and a switching arm 77 is provided that is rotatable around the fulcrum shaft 77a. The fulcrum shaft 77a serves as a rotation fulcrum for the switching arm 77. A switching operation unit is provided at the lower end of the switching arm 77, and operates the protrusion 71a of the regulator 71 to move the position of the regulator 71 relative to the pressure adjustment rod 55. The protrusion 69b slides movably within the second elongated hole 65 provided in the rotation restriction member 67.

[0048] The other end of the linking member 57 is connected to the upper end of the switching arm 77. As a result, the rotation of the operating arm 53 is linked to the switching arm 77. When the operating arm 53 rotates, the linking member 57 is pulled toward the operating arm 53, and the linking member 57 pulls the other end of the switching arm 77. As a result, the regulating body 71, which is made movable on one end of the switching arm 77, moves along the axial direction of the rod main body 61.

[0049] A return elastic body 79 is disposed on the switching arm 77. The return elastic body 79 is a member that biases the regulating body 71 in a direction that moves it away from the holding member 69, and in this embodiment, a coil spring disposed around the fulcrum shaft 77a is used as the return elastic body 79. The return elastic body 79 is biased so as to move the regulating body 71 toward the rotation fulcrum of the pressure adjustment rod 55. In other words, the upper end of the switching arm 77 is biased so as to pull the linking member 57. The operation of the operated linking member 57 is output by the switching arm 77 and output to the operating arm 53 of the attitude control unit 17. At this time, the operating arm 53 is pulled by the linking member 57, and the receiving portion 59 of the operating arm 53 is rotated so as to face the abutment portion 26 of the swing arm 25. In other words, the operating arm 53 and the switching arm 77, which are connected by the linking member 57, can both transmit force in only one direction.

[0050] The operating arm 53, which is pulled and rotated by the linking member 57, rotates within a rotation range defined by the rotation limiter 100a (shown in FIG. 3C). In other words, the abutting portion 26 and the receiving portion 59 can come into contact with each other only when the engaging portion 27 of the swing arm 25 is in the posture maintaining section R of the posture maintaining portion 24, and when the engaging portion 27 of the swing arm 25 is in the restricted range of the restricting hole 23, the abutting portion 26 and the receiving portion 59 cannot come into contact with each other.

[0051] Reference numeral 81 denotes an adjustment part connected to the pressure adjustment rod 55, which has an adjustment screw 83 consisting of a bolt and nut, and is rotatably connected to the pipe frame 85. The adjustment part 81 makes it possible to change the positional relationship between the protrusion 69a and the first elongated hole 63, thereby changing the range of rotation of the ground leveling bodies 31, 33. Reference numeral 87 denotes a rotation fulcrum for the rod. In the embodiment, the rotation fulcrum 87 is provided on the pipe frame 85, but it does not necessarily have to be on the pipe frame 85 as long as it is located above the cover body 35 in the unfolded state.

[0052] Reference numeral 100 denotes a link support member that fixes and supports the position of the interlocking member 57. As shown in FIGS. 3A and 3B, two link support members 100 are erected on the cover body 35, and as shown in FIGS. 8 and 9, they rotatably connect the first link 18, the actuator 43, the swing arm 25, the operating arm 53, and the cam link 37. Reference numeral 100a denotes a rotation limiting portion provided on the link support member 100, which is formed in a fan shape or a concave arc shape as shown in FIG. 3C. Reference numeral 100b denotes an opening formed opposite the rotation limiting portion 100a. Reference numeral 100c denotes a hook portion provided in the opening 100b. In the drawings, reference numeral 89 denotes a transmission unit, 91 denotes an input shaft, 93 denotes a second pipe frame, 95 denotes a chain case, 97 denotes a folding fulcrum portion, and 99 denotes a support member.

[0053] Here, we will explain how to change the rotation range of the leveling bodies 31, 33. The leveling bodies 31, 33 are provided on the main work body 2 and the side work body 3, respectively, and are arranged so that even when the side work body 3 is folded, the leveling board folds along with the cover body 35 and tilling section 11. The side work body 3 is arranged so that it can be used in both a stored state (folded) and an unfolded state. When unfolded, leveling performance is improved if the leveling bodies 31, 33 are connected and move up and down as a unit. When unfolded, the leveling bodies 31, 33 are connected and become a unit by fitting their mating parts together. When connecting, the leveling bodies 31, 33 may reach the end of the lower rotation direction due to gravity, and may not be able to be connected if their vertical positions are different. In such cases, the adjustment unit 81 is provided on the central working body 2 and the side working body 3, and by adjusting the rotation range of each leveling body 31, 33, the inconvenience is eliminated and each connection is made easier.

[0054] Next, the operation and effects of the embodiment will be described. In the agricultural work machine 1, rotational power is output from a drive source (not shown) via a speed change unit 89 and transmitted to a rotor shaft 13 (shown in Figure 2, etc.) via chain cases 95 attached to support members 99 (shown in Figure 1) on both sides of the central work body 2, thereby rotating and driving the tilling unit 11. The tilling unit 11 breaks up mud and soil clods with the rotating tines 15.

[0055] (Attitude control) First, the swing arms 25 of the posture control units 17 of the central work body 2 and each side work body 3 are operated, and the engaging parts 27 are engaged in the restricting holes 23 of the first links 18 (FIG. 5A). This causes the rear ends of the first links 18 to rotate downward, but this rotation is restricted, and the second leveling body 33, pushed downward by the second links 19, assumes an upright position as shown in FIG. 5A. Because the rotation of the first links 31 is restricted and fixed, the second links cannot move either. The rotation of both the first and second leveling bodies 31 and 33, which are rotatable, is restricted, and the contact position of the second leveling body 33 with the field is fixed. In this state, the machine is driven to perform soil piling work. Note that in this embodiment, FIG. 5A also shows the position of the engaging parts 27 when the side work bodies 3 are folded or unfolded, making it possible to prevent the rotation of the leveling bodies 31 and 33, which are upside down when the side work bodies 3 are folded. The plow work is carried out after the engaging portion 27 is moved from the restricted range C to the unrestricted range R.

[0056] The work performed by the agricultural implement 1 consists of mulching and puddling. Mulching is the work of moving the agricultural implement forward while it is inserted into the soil or mud, and puddling is the work of breaking up the muddy soil in the field and leveling the top surface of the field.

[0057] The soil-piling operation is performed by rotating the first soil leveling body 31 and the second soil leveling body 33 downward, with the second soil leveling body 33 reaching the bottom of its rotational direction and locked in place to prevent further rotation (FIG. 5A). During soil-piling, the first link 18 is locked, preventing the second soil leveling body 33 and the first soil leveling body 31 from rotating up and down. This allows each soil leveling body to maintain its posture while working. The soil-piling operation involves using the soil leveling bodies 31 and 33 to move mounded mud into a depressed field area and roughly level the surface. In many cases, soil-piling is performed before plowing using the tilling unit 11, and after the soil-piling operation, the machine is set for plowing. While the tilling unit 11 crushes the soil, the soil leveling boards 31 and 33 level the field. When the engaging portion 27 is positioned in the restricted range C, the first link 18 is prevented from rotating, thereby preventing the second leveling body 33 from rotating around the first leveling body 31 via the second link 19. At this time, the first leveling body 31, which is connected to the cover body 35 and the second leveling body 33, is also prevented from rotating up and down. In the restricted range state, the second leveling body 33 and the first leveling body 31 are fixed with their rear ends facing downward, making it easier for the rear end of the second leveling body 33 to penetrate into the soil or mud. If the work machine is advanced while the second leveling body 33 is penetrated into the soil or mud, the mud located in front of the leveling body can be moved. Even during the pile-up operation, the second leveling body 33 and the first leveling body 31 are prevented from rotating up and down, allowing each leveling body to maintain its posture. The mud crushed by the tilling section 11 is prevented from scattering because the cover body 35 covers the upper side of the tilling section 11 to the rear.

[0058] Next, the swing arms 25 of the central working body 2 and each side working body 3 are operated, and the engaging parts 27 are moved to the posture maintaining parts 24 of the first links 18 shown in Figure 5B. The rear end of the second leveling body 33 is lifted upward by the first links 18 being pushed up by the engaging parts 27. This prepares the second leveling body 33 for plowing.

[0059] Next, when the agricultural work machine 1 is lowered to insert the tilling unit 11 into the soil, the leveling bodies 31, 33 that are in contact with the field are pushed upward by the mud and soil, causing the released first link 18 to further rotate and rise to the position shown in Figure 5C. Then, the second link 19 rises and changes from an upright position to an inclined position, so that the second leveling body 33 becomes horizontal. In this position, the traveling body travels to perform the tilling work.

[0060] When the engaging portion 27 is positioned on the posture maintaining portion 24, i.e., when the engaging portion 27 is in the posture maintaining section R, the first link 18 is only prevented from rotating downward, but its upward rotation is not restricted (Figure 5B). In this plowing state, the second leveling body 33 is prevented from rotating downward around the first leveling body 31 as a fulcrum. Furthermore, the second leveling body 33 is not prevented from moving upward or rotating around the first leveling body 31 as a fulcrum. Therefore, the first leveling body 31 can also rotate upward, and the first leveling body 31 and the second leveling body 33 can rotate freely upward, so they rotate to press down on the top surface of the mud, leveling the top surface of the mud. Furthermore, the rear end of the second soil leveling body 33 during the puddling operation is raised higher than the rear end of the second soil leveling body 33 when the soil is being piled up, and downward rotation is prevented. This position prevents the second soil leveling body 33 from sticking into the soil when the implement is positioned in the soil to perform the puddling operation. This prevents the muddy soil from being dug up at the start of the puddling operation, allowing for even more level soil leveling.

[0061] The posture maintaining part 24 of the first link 18 is formed in a concave arc shape so that the center of the arc coincides with the center of rotation of the swing arm 25, so the posture of the leveling bodies 31, 33, such as their angle and position, which have reached the lower end in the rotation direction, does not change depending on the engagement position of the engagement part 27 and the posture maintaining part 24. In other words, no matter what the engagement position of the engagement part 27 and the posture maintaining part 24 is, the posture of the leveling bodies 31, 33 can be prevented from sticking into the ground.

[0062] During the tilling operation, the engagement portion 27 of the swing arm 25 is positioned at the first posture maintenance point 24a in the posture maintenance section R. Meanwhile, the abutment portion 26 abuts against the receiving portion 59 of the operating arm 53 and presses against the receiving portion 59. In this state, even if the first link 18 rotates from the position in FIG. 5B to the position in FIG. 5C, that is, even if the engagement portion 27 of the first link 18 rotates upward so as to move away from the guide portion 21, the positional relationship between the engagement portion 27 and the abutment portion 26 and the positional relationship between the receiving portion 59 and the abutment portion 26 do not change.

[0063] As shown in FIG. 5C , the abutment portion 26 presses the receiving portion 59, which is in an upright position, to move the regulating body 71 of the pressure adjusting unit 51 via the linking member 57 and the switching arm 77. The positional relationship between the abutment portion 26 and the receiving portion 59 remains unchanged because the swing arm 25 does not rotate via the cam link 37 unless the actuator 43 operates. Meanwhile, the regulating body 71 contacts the first elastic body 73 as the first leveling body 31 rises, generating a pressing force that rotates the first leveling body 31 downward. The regulating body 71 receives a repulsive force from the first elastic body 73, which operates the switching arm 77 and attempts to operate the operating arm 53 via the linking member 57. However, even if the abutment portion 26 operates in a direction that presses the receiving portion 59, the operating arm 53 cannot rotate because the abutment portion 26 does not move. That is, even if the restricting body 71 receives a force from the first elastic body 73 to move the restricting body 71, the movement is prevented by the abutting portion 26 which does not move. The second soil leveling body 33 presses against the top surface of the field by its own weight at the pivot point 33a at the rear end of the first soil leveling body 31. In other words, the second soil leveling body 33 presses against the field surface while keeping its lower surface horizontal by its own weight and / or the weight of the second soil leveling body 33 plus the weight of the first link 18 and the second link 19, thereby leveling the field surface. Therefore, even if the second soil leveling body 33 receives a force from the top surface of the field during plowing work, it will not lose its horizontal posture for leveling, regardless of the force the first soil leveling body 31 receives from the field or the first elastic body 73.

[0064] When the engaging portion 27 is at the first attitude maintaining point 24a, the operating arm 53 does not output any motion to the linking member 57, so the positional relationship between the rod main body 61 and the regulating body 71 is the same as when in the puddling state. During plowing work, the swinging arm 25 can move to any position in the attitude maintaining section R of the first link 18 depending on the shape of the top surface of the field. The pressure regulation control of the pressure regulating unit 51 during the plowing operation in FIG. 5C will be described later with reference to FIGS. 6B and 6C.

[0065] 5D and 5E show the case where the contact portion 26 of the swing arm 25 moves from the first posture maintenance point 24a to the second posture maintenance point 24b in the posture maintenance section R. At this time, the contact portion 26 comes into contact with the receiving portion 59 of the operating arm 53, which is in a substantially horizontal position, and presses against the receiving portion 59. In this state, even if the first link 18 rotates from the preparation position shown in FIG. 5D to the working position shown in FIG. 5E, the positional relationship between the engaging portion 27 and the contact portion 26 remains unchanged. On the other hand, when the swing arm 25 is moved from the state shown in FIG. 5D to the state shown in FIG. 5B, the engaging portion 26 moves away from the receiving portion 59, as shown in FIG. 5A.

[0066] Therefore, the pressing force of the second soil leveling body 33 during the plowing operation is the same as that described in Figures 5C and 5D. That is, the contact portion 26 presses the receiving portion 59, which is in a substantially horizontal position as shown in Figure 5D, but even when the receiving portion 59 is pressed by the contact portion 26, it only moves the regulating body 71 of the pressure adjusting portion 51, and the horizontal position of the second soil leveling body 33 for leveling is not disturbed. In other words, because the downward rotation of the first link 18 is restricted by the engaging portion 27 and the position maintaining section R, the position of the rotation fulcrum 33a when the first soil leveling body 31 rotates downward is also the same, and the second soil leveling body 33 can assume the same position when it reaches the bottom. In other words, when the ground leveling bodies 31, 33 are positioned at the lower end in the rotation direction, the first ground leveling body 31 and the second ground leveling body 33 can always maintain the same position, so that when the ground leveling bodies 31, 33 are placed on the field, a stable ground contact state can be created. Also, when positioned within the rotation limiting part 100a, the receiving part 59 maintains a contact state with the contact part 26 via the linking member by the switching arm 77 biased by the return elastic body 79 located in the pressure adjusting part 51.

[0067] The posture of the first link 18 does not change when it reaches the lower end of its rotation direction while the engagement portion 27 of the swing arm 25 is engaged with the posture maintenance section R, that is, the entire section while it is located from the first posture maintenance point 24a to the second posture maintenance point 24b of the posture maintenance section 24. The posture maintaining portion 24 is formed in a concave arc shape, and the center of the arc coincides with the rotation fulcrum of the swing arm 25. In other words, as long as the engaging portion 27 is positioned in the posture maintaining section R, the posture of the first link 18 does not change, and as a result, the lower end of the second leveling body 33 does not fluctuate as it rotates downward.

[0068] When the engagement portion 27 is at the second posture maintenance point 24b, the operating arm 53 does not output any motion to the linking member 57 unless the swing arm 25 is rotated, so the positional relationship between the rod main body 61 and the regulating body 71 does not change. The pressure regulation control of the pressure regulating unit 51 during the puddling operation of FIG. 5D will be described later with reference to FIGS. 6D and 6E.

[0069] Here, we will explain the movement of the leveling bodies 31, 33 when the engaging portion 27 is moved from the restricting hole 23, where the restricted range C is formed, to the unrestricted range, i.e., the posture maintaining portion 24, where the posture maintaining section R is formed. As the engaging portion 27 moves to the posture maintaining section R via the cam link 37, the rear end of the first link 18 rotates upward, and the rear end of the second leveling body 33 also rotates upward via the second link 19. When the engaging portion 27 reaches the posture maintaining section R, the restriction on the upward rotation of the first link 18 is released, and the rotation of the first leveling body 31 and the second leveling body 33 is also released. At the same time, the engaging portion 26 and the receiving portion 59 begin to come into contact with each other.

[0070] When the swing arm 25 is moved from the unrestricted range of the first link 18 to the restricted range C via the cam link 37 (FIG. 5A), the operating arm 53 rotates until it reaches the limit of the rotation range of the rotation restricting portion 100a, and then it cannot rotate any further, so that the abutment state between the engaging portion 26 and the receiving portion 59 is released and only the swing arm 25 rotates (FIG. 5A).

[0071] Here, the interlocking relationship between the link support member 100, the first link 18, the swing arm 25, the operating arm 53, and the linking member 57 can be summarized with reference to Figures 8 and 9. Only when the engaging portion 27 is in the posture maintaining section R does the abutting portion 26 press the receiving portion 59 of the operating arm 53. On the other hand, when the swing arm 25 rotates in the other direction, that is, when the engaging portion 27 is not in the posture maintaining section R, the abutting portion 26 escapes from the opening 100b and does not press the receiving portion 59 of the operating arm 53.

[0072] (Pressure regulation control) Next, pressure control by the pressure adjusting unit 51 will be described with reference to Figures 6A to 6E. Figure 6A shows the state of the pressure adjusting rod 55 when the swing arm 25 is located in the regulation range C shown in Figure 5A. Figure 6B shows the state of the pressure adjusting rod 55 when the swing arm 25 is located at the first attitude maintenance point 24a shown in Figure 5B. Figure 6C shows the state when the swing arm 25 is located at the first attitude maintenance point 24a shown in Figure 5C, and the second soil leveling body 33 has risen to a horizontal position for plowing work. Figure 6D shows the state of the pressure adjusting rod 55 when the swing arm 25 is located at the second attitude maintenance point 24b shown in Figure 5D. Figure 6E shows the state when the swing arm 25 is located at the second attitude maintenance point 24b shown in Figure 5E, and the second soil leveling body 33 has risen to a horizontal position for plowing work.

[0073] When the swing arm 25 is operated to position the engagement portion 27 in the restricted range C, the second ground leveling body 33 enters the soil-pile state, and at the same time, the posture of the first ground leveling body 30 is fixed (FIG. 5A). At this time, the abutment portion 26 also moves integrally with the swing arm 25 toward the restricted range C, but the receiving portion 59 of the operating arm 53 separates from the abutment portion 26 of the swing arm 25 because the rotation of the operating arm 53 is restricted by the rotation restricting portion 100a (FIG. 5A). Furthermore, the switching arm 77, which is biased by the return elastic body 79, operates the linking member 57 to operate the operating arm 53, and the operating arm 53 rotates until it is restricted by the rotation restricting portion 100a. At this time, the restricting body 71 has moved toward the rotation fulcrum 87 of the rod (FIG. 6A).

[0074] 6A, during the piling operation, the engaging portion 27 of the swing arm 25 is engaged with the restricting hole 23 of the first link 18, and the abutting portion 26 is separated from the receiving portion 59 and does not press against the receiving portion 59. Therefore, the pressure that the second ground leveling body 33 receives from the top surface of the field is not mechanically transmitted to the operating arm 53. Therefore, the posture of the second ground leveling body 33, which is in a substantially upright state, is maintained, and the piling operation can continue. At this time, the first elastic body 73 and the second elastic body 75 of the pressure adjusting rod 55 remain in their initial positions. In the illustrated central working body 2, the first link 18 and the second link 19 are positioned so as to overlap, in the fore-aft direction, with the top mast 7 and the transmission unit 89, which are located in the left-right center of the central working body 2 in the direction of travel. As a result, the first link 18 and the second link 19 can receive the load on the second soil leveling unit 33 at the center of the second soil leveling unit 33 during soil piling work, preventing the load from being applied in a direction that would cause the second soil leveling unit 33 to twist unevenly from side to side. The actuator 43, cam link 37, and swing arm 25 that operate the first link 18 are also positioned so that they overlap the top mast 7 and the transmission unit 89 in the front-to-rear direction. The actuator 43, which is the drive device that operates the soil leveling units 31 and 33, is positioned so that it fits within the projection plane of the top mast 7 and the transmission unit 89 in the front-to-rear direction of the traveling direction, making it invisible to the operator aboard the traveling machine body. Even if the operator looks behind the agricultural work machine 1 in the traveling direction to check the working status, the field of view is not obstructed, making it easy to check the working status.

[0075] When the swing arm 25 is operated to position the engagement portion 27 at the first position maintenance point 24a in the position maintenance section R, the second leveling body 33 enters the puddling state. At this time, the abutment portion 26 also moves integrally with the swing arm 25 toward the position maintenance section R (Fig. 5B). The receiving portion 59 of the operating arm 53 also comes into contact with the abutment portion 26 of the swing arm 25. When the operating arm 53 is at the first position maintenance point 24a, it does not output any motion to the linking member 57, so the positional relationship between the pressure adjustment rod 55 and the regulating body 71 remains the same as when it is in the pile-up state, and the regulating body 71 remains in the position where it has moved toward the rod's pivot fulcrum 87 (Fig. 6B).

[0076] At the first posture maintaining point 24a in the posture maintaining section R, the first ground leveling body 31 is rotatable at the rear end of the cover body 35, and the second ground leveling body 33 is rotatable at the rear end of the first ground leveling body 31 (Fig. 5C). In the illustrated embodiment, even if the first ground leveling body 31 is rotated up and down at the first posture maintaining point 24a, the first elastic body 73 does not reach the regulating body 71, so the ground leveling bodies 31, 33 are not urged to rotate downward. In other words, the ground leveling bodies 31, 33 impart a load due to their own weight to the field surface.

[0077] Next, when the first leveling body 31 and the second leveling body 33 perform tillage work while the engagement portion 27 of the swing arm 25 is positioned at the first attitude maintenance point 24a of the first link 18 (Figure 5C), the pressure that the first leveling body 31 receives from the top surface of the field causes the retaining member 69 in the pressure regulating rod 55 to be pushed from the position in Figure 6B to the position in Figure 6C. That is, in Figures 6B and 6C, during tillage work, the pressure that the first leveling body 31 and the second leveling body 33 receive from the top surface of the field causes the retaining member 69 of the pressure adjusting rod 55 to be pushed from the position in Figure 6B to the position in Figure 6C, but the pressure is absorbed by the load due to the weight of the first elastic body 73 and the first leveling body 31 and the second leveling body 33, so the first leveling body 31 and the second leveling body 33 apply pressure to the top surface of the field to level it.

[0078] Next, we will explain the case where the second soil leveling body 33 performs puddling work while the engaging portion 27 of the swing arm 25 is positioned at the second attitude maintenance point 24b of the first link 18. In Figures 6D and 6E, when the first soil leveling body 31 and the second soil leveling body 33 receive pressure from the top surface of the field during puddling work, the pressure regulating rod 55 moves the rod body 61, and the retaining member 69 moves as the first soil leveling body 31 moves up and down, pushing the first elastic body 73 located between the rod body 61 and the regulating body 71, causing the first elastic body 73 to contract from the position shown in Figure 6D to the position shown in Figure 6E. In this way, the biasing force of the first elastic body 73 is activated, and the second soil leveling body 33 and the first soil leveling body 31 apply pressure to the top surface of the field, leveling it.

[0079] In the posture maintaining section R, the position can be freely changed from the first posture maintaining point 24a to the second posture maintaining point 24b. As the swing arm 25 is rotated from the first posture maintaining point 24a to the second posture maintaining point 24b, the abutment portion 26 presses the receiving portion 59, causing the operating arm 53 to rotate. The operating arm 53 pulls the linking member 57, thereby pulling the upper end of the switching arm 77 forward and moving the regulating body 71 toward the holding member 69 (FIGS. 6C to 6E).

[0080] When the engaging portion 27 is moved from the first posture maintaining point 24a toward the second posture maintaining point 24b (FIG. 5D), the regulating body 71 comes closest to the holding member 69 (FIG. 6D). As the distance between the regulating body 71 and the holding member 69 decreases, the rotation height of the soil leveling body 31 at which the regulating body 71 comes into contact with the first elastic body 73 can be changed. In the puddling state where the engaging portion 27 is located in the posture maintaining section R, the swing arm 25 can be rotated regardless of whether the soil leveling bodies 31, 33 are rotating. In other words, in the puddling state, the engaging portion 27 can be freely moved between the first posture maintaining point 24a and the second posture maintaining point 24b.

[0081] When the engaging portion 27 is moved from the first position maintaining point 24a toward the second position maintaining point 24b (FIG. 5E), the regulating body 71 comes closest to the holding member 69 (FIG. 6D). Therefore, when the first ground leveling body 31 is positioned near the bottom end in the rotation direction, the regulating body 71 comes into contact with the first elastic body 73. In this state, the height to which the ground leveling body 31 is biased is lower than when the engaging portion 27 is positioned at the first position maintaining point 24a. In other words, in the plowing state, the timing at which the ground leveling body 33 is biased downward is advanced, and the amount by which the first elastic body 73 is compressed by the upward rotation of the ground leveling body 31 increases (FIGS. 5E and 6E). Therefore, the force biasing the ground leveling body 31 downward increases. Therefore, during the plowing operation, the pressure adjusting rod 55 is pushed upward by the pressure that the first soil leveling body 31 and the second soil leveling body 33 receive from the top surface of the field, which also pushes the holding member 69 upward (Fig. 6E). At this time, the distance between the regulating body 71 and the holding member 69 decreases, increasing the repulsive force of the first elastic body 73 and urging the first soil leveling body 31 to rotate downward. Because the first soil leveling body 31 and the second soil leveling body 33 exert the repulsive force of the first elastic body 73 in addition to their own weights, when the engaging portion 27 is positioned at the second posture maintaining point 24b compared to when it is positioned at the first posture maintaining point 24a, the first soil leveling body 31 and the second soil leveling body 33 apply more pressure to the top surface of the field, leveling it.

[0082] In other words, when the first soil leveling unit 31 rotates, the holding member 69 supported by the holding plate 32 and the first elastic body 73 located between the regulating body 71 and the holding member 69 move along the rod main body 61. When the regulating body 71 is farthest from the holding member 69 and the engaging part 27 is at the first attitude maintenance point 24a, even if the first soil leveling unit 31 is rotated upward from Figure 6B to Figure 6C, the first elastic body 73 does not reach the regulating body 71, so the first elastic body 73 is not compressed and the biasing force is not transmitted to the first soil leveling unit 31. The load on the field is the weight of the first soil leveling unit 31 and the weight of the second soil leveling unit 33 alone. In contrast, when the first soil leveling unit 31 is moved from the first attitude maintaining point 24a toward the second attitude maintaining point 24b, as shown in FIG. 5B to FIG. 5D, the regulating body 71 moves toward the holding member 69. At this time, if the first soil leveling unit 31 rotates upward due to a convex portion of the field, as shown in FIG. 6D to FIG. 6E, the first elastic body 73 quickly comes into contact with the regulating body 71. This compresses the first elastic body 73, transmitting a biasing force to the first soil leveling unit 31. The load on the field is the sum of the weight of the first soil leveling unit 31 and the weight of the first elastic body 73, plus the weight of the second soil leveling unit 33, resulting in soil leveling. In the case of FIG. 6D, when the first soil leveling unit 31 is at the bottom end position in the rotation direction, the regulating body 71 and the first elastic body 73 are already in close proximity. Therefore, even a slight upward rotation of the first soil leveling unit 31 compresses the first elastic body 73. Furthermore, since the engaging portion 27 can be freely moved from the first attitude maintaining point 24a toward the second attitude maintaining point 24b, the rod main body 61 of the regulating body 71 can also be freely positioned in conjunction with this. In other words, by moving the regulating body 71, the timing of contact between the regulating body 71 and the first elastic body 73 can be changed when the first ground leveling body 31 rotates upward. As a result, the downward biasing force of the first ground leveling body 31 can be changed.

[0083] Even if the engaging portion 27 is moved from the first posture maintaining point 24a toward the second posture maintaining point 24b, the posture at the bottom dead center D (shown by the two-dot chain line in Figures 5A, 5C, and 5E) where the first link 18 rotates does not change. Therefore, the posture of the second soil leveling body 33 before it touches down on the field surface remains constant, and the upward rotation of the soil leveling body is stabilized. Therefore, the soil leveling bodies 31, 33 can be placed on the field surface without damaging it.

[0084] In this embodiment, the movement of the swing arm 25, i.e., the movement from the restricted range C to the posture maintenance section R including the first posture maintenance point 24a and the second posture maintenance point 24b, is performed by remote control without the need for manual operation by an operator, since an actuator is used.

[0085] When the swing arm 25 is moved from the second position maintenance point 24b toward the first position maintenance point 24a, the abutment portion 26 of the operating arm 53 rotates so as to move away from the receiving portion 59. However, when the operating arm 53 is rotated by the linking member 57 connected to the upper end of the switching arm 25, the operating arm 53 rotates in a state in which the abutment portion 26 and the receiving portion 59 are in contact so as to follow the swing arm 25 (FIGS. 5D to 5C). Then, when the swing arm 25 is moved from the position maintenance section R of the first link 18 to the restricted range C, the operating arm 53 rotates until it reaches the limit of the rotation range of the rotation restrictor 100a, after which it cannot rotate further due to the presence of the hook portion 100c, so the abutment state between the abutment portion 26 and the receiving portion 59 is released and only the swing arm 25 rotates (FIG. 5A).

[0086] 5B to 5D, the abutment portion 26 does not move away from the receiving portion 59. On the other hand, when the engagement portion 27 moves from the second attitude maintenance point 24b toward the first attitude maintenance point 24a, the abutment portion 26 of the swing arm 25 rotates away from the receiving portion 59 of the swing arm 25. In other words, the operating arm 53 rotates in a state where the abutment portion 26 and the receiving portion 59 are in contact with each other so as to follow the swing arm 25 (FIGS. 5D and 5B).

[0087] By the above-described series of mechanisms and operations, even though the driving source for the pressure adjustment unit 51 and the posture control unit 17 is the same, it is possible to freely change the pressure adjustment, which is the adjustment of the force applied to the ground leveling bodies 31, 33, and to change the posture of the ground leveling bodies 31, 33.

[0088] Let's compare the puddling work shown in Figure 6C with the puddling work shown in Figure 6E. When the engagement part 27 is located at the first attitude maintenance point 24a (Figure 5B), the regulating body 71 moves toward the adjustment part 81 (Figure 6B). Therefore, in this embodiment, the first elastic body 71 is not compressed and does not exert a biasing force pushing the soil leveling bodies 31, 33 downward, or the amount of compression of the elastic body 73 is reduced, weakening the suppressing force. Therefore, the force suppressing the muddy soil surface is the weight of the soil leveling bodies 31, 33 itself, or its own weight plus a weak biasing force, making it easier for muddy soil that has passed through the tilling part 11 to pass under the soil leveling bodies 33. Conversely, when it is located at the second attitude maintenance point 24b (Fig. 5D), the regulating body 71 moves toward the holding member 69 (Fig. 6D). The first elastic body 73 is located between the regulating body 71 and the holding member 69, whose relative positions change as the leveling bodies 31, 33 rotate, and therefore exerts an urging force that pushes the leveling bodies 31, 33 downwards through compression. Therefore, the force holding down the muddy soil surface is exerted by the weight of the first leveling body 31 and the second leveling body 33 in addition to the strong urging force, and mud that has passed through the tilling section cannot easily pass under the leveling bodies 31, 33.

[0089] In an actual field, when the soil is easy to crush (for example, soft and brittle soil), leveling work is performed by positioning the leveler at the first attitude maintenance point 24a. When the soil is of this type, if it is positioned at the second attitude maintenance point 24b, the downward pressure of the leveling unit 31 will gouge out the soil itself, resulting in an uneven leveling result. Conversely, when the soil is difficult to crush (for example, clayey soil that easily hardens and is difficult to crush), leveling work is performed by positioning the leveler at the second attitude maintenance point 24b. When the soil is of this type, even if it is muddy, the soil is difficult to move when pressed by the leveling unit 31, so it may not be possible to level the ground by pressing only with the weight of the leveling units 31 and 33. To prevent this, the downward pressure of the leveling unit 31 is increased, forcing the soil to move while leveling. In addition, since the soil leveling bodies 31 are pressed downward, it becomes easier to retain soil clods between the soil leveling bodies 31, 33 and the tilling section 11, and soil crushing in the tilling section 11 can also be promoted.

[0090] Furthermore, by changing the receiving portion 59 from a substantially upright position as shown in FIG. 5C to a substantially horizontal position as shown in FIG. 5E, the actuator 43 can operate the switching arm 77 via the linking member 57 connected to the receiving portion 59. This moves the regulating body 71 on the rod main body 61 from the position shown in FIG. 6C to the position shown in FIG. 6E. This produces the desired effect (strong pressing force at the second attitude maintenance point 24b). In this case, since the center of the arc of the attitude maintenance portion 24 coincides with the center of rotation of the swing arm 25, even if the position of the engaging portion 27 changes relative to the attitude maintenance portion 24, the lower end position of the soil leveling body 33 relative to the rotation direction when not in contact with the mud remains unchanged. In other words, even if the biasing force of the elastic body 73 increases or decreases, the lower end position of the soil leveling body 333 relative to the rotation direction remains constant. This allows the soil leveling bodies 31, 33, which are positioned on muddy soil during plowing, to be lowered and placed on the muddy soil while maintaining a constant angle and relative positional relationship. Therefore, even if the biasing force increases or decreases, the degree of contact with the soil when the ball touches the ground remains constant.

[0091] Next, the effects of puddling work at the first posture maintenance point 24a (Fig. 5B) and the effects of puddling work at the second posture maintenance point 24b (Fig. 5C) will be explained. Fig. 5B shows the state before the puddling implement touches down in the mud, and Fig. 5C shows the state after the puddling implement touches down in the mud and is currently working. The same is true for the puddling work in the positions shown in Figures 5D and 5E. In both cases, the position before the puddling work at the first position maintenance point 24a and the second position maintenance point 24b is constant, so the angle of the soil leveling body relative to the ground is constant, which reduces the amount of mud digging or digging by the soil leveling body when it is placed on muddy soil.

[0092] Furthermore, because this embodiment has a foldable structure, when the leveling bodies 31 and 33 are rotated downward (FIG. 5A), or when the side working bodies are deployed with the swing arms positioned between FIGS. 5B and 5D, the leveling bodies of each working body (the first leveling bodies 31 and the second leveling bodies 33) must be interlocked. That is, the leveling bodies 31 and 33 must be aligned to the same angle and position. In this case, the positions of the lower rotation ends of the leveling bodies 31 and 33, formed by the first attitude maintaining point 24a and the second attitude maintaining point 24b, are determined, so there is no interlocking problem caused by misalignment of the leveling bodies 31 and 33. Here, "interlocking" refers to the joining and alignment of the ends of the first leveling body 31 and the second leveling body 33 of each working body 2 and 3 so that they can operate as a unit in the deployed position.

[0093] 5C shows that the engaging portion 27 is not at the first attitude maintaining point 24a, which indicates that the first leveling body 31 and the second leveling body 33 are pushed up. The lower portion of the rotating tilling unit 11 enters the mud, stirring and crushing the mud, and the first leveling body 31 and the second leveling body 33 are positioned on the surface of the mud after crushing (in other words, they are positioned so as to float on the surface of the mud). In this case, the first leveling body 31 and the second leveling body 33 are pushed up, and the first link 18 rotates in conjunction with the movement of each leveling body 31, 33.

[0094] In FIG. 5E, the engaging portion 27 is not at the second attitude maintaining point 24b, but this is also the same as what has been described with reference to FIG. 5C.

[0095] 5B and 5D, it can be seen that the same puddling work can be performed at either the first attitude maintenance point (Fig. 5B) or the second attitude maintenance point (Fig. 5D). In addition, in this embodiment, the lower end positions of the ground leveling bodies 31 and 33 in the rotation direction can be made the same, which makes it easier to align the ground leveling bodies 31 and 33 when folding.

[0096] The first leveling body 31 and the second leveling body 33, which are arranged as separate bodies on the central working body 2 and the side working body 3, respectively, can move integrally with each other when they are fitted together so that the second leveling bodies 33 cannot move back and forth or rotate about each other's rotation axis. This means the following. Let us consider a case where the rotation position of the first link 18 is in a restriction release range that differs depending on the engagement position at the first posture maintenance point 24a and the second posture maintenance point 24b. In other words, even if one first link 18 is at the first posture maintenance point 24a and the other is at the second posture maintenance point 24b, the angle of the second leveling body 33 is constant, which means that the two second leveling bodies 33 can be fitted together at the same angle and orientation. In other words, the first leveling body 31 and the second leveling body 33 on the side working body 3 and the central working body 2 cannot be fitted together unless they are at the same angle and positional relationship with each other, and if they cannot be fitted together, the leveling performance will be reduced.However, in this embodiment, when the leveling bodies 31 and 33 are positioned downward, they can be in the same posture (rotation angle).

[0097] In this embodiment, when the engaging parts 27 are in the restricted position within restricted range C, the side working body 3 can be folded and unfolded as shown in Figures 10 and 11. This is because even if the side working body 3 is folded upside down while the engaging parts 27 of the side working body 3 are in the restricted position within restricted range C, the positions of the first leveling body 31 and second leveling body 33 of the side working body 3 are fixed and stable.

[0098] In the folded state, the central work body 2 can release the rotational lock of the first link 18 and perform the above-described plowing work. The posture control unit 17 disposed on the central work body 2 in this embodiment allows the posture control unit 17 to be located in the center of the central work body 2. Therefore, even when the side work bodies 2 located on both sides of the central work body 2 are folded, the posture control unit 17 can be located exactly in the center of the side work body 2, so that plowing work using only the central work body 2 is not hindered. Furthermore, because the space S formed behind and above the posture control unit 17 creates an empty area, even if a side work body 3 in the folded state is located above the posture control unit 17 of the central work body 2, mutual interference can be prevented. Furthermore, mutual interference can also be prevented when performing plowing work using only the central work body 2 in this state.

[0099] In the above embodiment, the engaging portion 27 is positioned in the restricted range C when the side working body 3 is folded or unfolded. However, if a mechanism for preventing the first link 18 from rotating is added, the side working body 3 may be folded or unfolded with the engaging portion 27 positioned in the unrestricted range R.

[0100] The work machine according to the present invention is not limited to the above embodiment. For example, the positional relationship between the restricted area C and the posture maintaining section R provided in the first link 18 may be opposite to that of the above embodiment, with the restricted area C provided forward in the direction of travel and the posture maintaining section R provided backward in the direction of travel, as shown in Figure 12.

[0101] Furthermore, the manner in which the attitude control unit 17 and / or the pressure adjustment unit 51 are installed and the number thereof are optional. As in the above embodiment, the attitude control unit 17 and the pressure adjustment unit 51 may be installed on all of the working bodies, or the attitude control unit 17 and / or the pressure adjustment unit 51 may be installed only on the central working body 2 or only on the side working body 3. When a single attitude control unit 17 and a single pressure adjustment unit 51 are used, the drive source and the aircraft configuration can be simplified. Furthermore, if the rotation of the second ground leveling body 33 is restricted by the posture control unit 17 and the rotation of the first ground leveling body 31 is restricted by the pressure adjustment unit 51, the ground leveling bodies 31, 33 can be positioned appropriately as a whole working machine. In this case, when the central working body 2 and the side working body 3 are connected, the connection can be made even smoother.

[0102] There is no limit to the number of attitude control units 17 that can be installed in the agricultural work machine 1. The attitude control unit 17 can also be operated by an operator on board the traveling machine body. In this case, by visually checking the gauge 47 and the scale plate 49, it is possible to easily determine the position of the engagement unit 27.

[0103] Furthermore, although the posture control unit 17 in the embodiment has been described as being positioned behind the mounting unit and / or the transmission unit 89, it may also be positioned on a side work body 3, for example, where there is no mounting unit or transmission unit 89. This is effective when it is not desirable to have the actuator 43 protrude from the rear end of the cover body 35, or when a structure is installed forward of the center of the cover body 35, making it difficult to position the posture control unit 17 including the actuator 43. In other words, by positioning the actuator 43 at the rear end of the cover body 35 and allowing the rod 43b to protrude downward, the rod 43b does not obstruct visibility even when the actuator 43 is operating. Furthermore, because the structure and the posture control unit 17 including the actuator 43 appear integrated forward of the center of the cover body 35, the aesthetic appearance of the agricultural work machine 1 can be improved. Furthermore, if the actuator 43 is positioned so that it fits within the projection plane in the direction of travel, the aesthetic appearance can be further improved.

[0104] The actuator may be a motor. The motor's rotation shaft is connected to swing arm 25 so as to swing, thereby enabling engagement portion 27 to abut against attitude maintenance section R from restricted range C of guide portion 21. In this case, the aesthetic appearance can be further enhanced by arranging motor 43, which is the actuator, within the projection plane of mounting portion and transmission unit 89 or other structures in the direction of travel. Also, a sensor can detect the rotation angle of the motor's rotation shaft to detect and grasp the abutment position of engagement portion 27. Furthermore, the biasing force of the first elastic body 73 can be freely changed and altered to a desired force to rotate the leveling board 33 downward at a timing preferred by the operator.

[0105] The present invention has been described above and with reference to the drawings, but the drawings are schematic and the dimensional relationships of the various parts may differ from the actual ones. Furthermore, the technical idea of ​​the present invention can be modified in various ways within the technical scope defined by the claims. [Industrial Applicability]

[0106] The present invention can be used in agricultural work. [Explanation of symbols]

[0107] 1 Agricultural machinery 2 Central working body 3 Side working body 4 machine frame 7 Topmast 8 Top Pin 9 Lower Pin 11 Cultivation Department 13 Rotor shaft 15 Nails 17 Attitude control unit 18 Link 1 18a Pivot point of first link 19 Second Link 21 Information Department 23 Restriction hole 24 Posture maintenance part 24a 1st posture maintenance point 24b 2nd posture maintenance point 25 Swing arm 25a Swing arm pivot point 26 Contact part 27 Engagement part 31 First leveling body 31a Pivot point of first leveling body 32 Holding plate 33 Second leveling body 33a Pivot point of second leveling body 35 Cover body 37 Camlink 39 Cam hole 41 Cam engagement portion 43 Actuator 43a Cylinder 43b Rod 45 link arm 47 gauge 49 Scale plate 51 Pressure adjustment section 53 Operating arm 53a Pivot point of operating arm 55 Pressure adjusting rod 57 Linking components 59 Receiving 61 Rod body 63 1st long hole 65 2nd long hole 67 Rotation restriction member 69 Retaining member 69a Protrusion 71 Regulatory Body 73 First Elastic Body 75 Second Elastic Body 76a pin 76b pin 77 Switching arm 77a Switching arm pivot point 79 Return elastic body 81 Adjustment section 83 Adjustment screw 85 Pipe Frame 87 Pressure adjusting rod rotation fulcrum 89 Transmission 91 Input shaft 93 Second Pipe Frame 95 Chain Case 97 Folding support point 99 Support member 100 Link support member 100a Rotation limiting part 100b aperture 100c hook C. Regulatory Scope R Posture maintenance section D bottom dead center H protruding position L Retracted position M intermediate position

Claims

1. a machine frame having a transmission unit that acquires power from a traveling machine body on which an operator rides; A tilling unit that tills using power transmitted from the speed change unit; A ground leveling body whose posture can be changed at the rear side of the tilling unit; an actuator that changes the posture of the ground leveling body and is provided at a position that is not visible to the worker; An agricultural machine characterized by comprising:

2. the actuator includes a cylinder and a rod that can move forward and backward relative to the cylinder, The rod does not obstruct the view of the operator while the actuator is in operation.

2. The agricultural implement according to claim 1.

3. The actuator is located behind the transmission unit.

3. The agricultural implement according to claim 2.

4. The actuator does not protrude rearward from the rear end of the cover body.

3. The agricultural implement according to claim 2.

5. the machine frame includes a mounting portion having a top mast; The actuator does not protrude above the top mast.

3. The agricultural implement according to claim 2.

6. The actuator is located aft of the top mast.

6. The agricultural machine according to claim 5.

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