JP7387839B2 - rice transplanter - Google Patents

Description

The present invention relates to a rice transplanter that continuously performs seedling planting work by attaching a seedling planting device having a seedling stand and a plurality of planting claws to a traveling machine body.

In a conventional rice transplanter, a seedling planting device having a seedling mounting stand and a transplanting mechanism with a planting claw is attached to the rear of the traveling machine. The transplanting mechanism of a seedling planting device is generally of the type in which two planting claws are provided in one rotary case, and when the rotary case rotates once, the two planting claws move in the opposite direction to the rotary case. Rotate once in the direction. That is, the planting claw rotates while revolving around the axis of the rotary case.

In seedling planting work using this type of rice transplanter, the seedling tray on which the seedling mat is placed is intermittently moved laterally from side to side at predetermined intervals, and the planting claws are moved in the direction of the seedling tray in front. By rotating around the axis of the rotary case and rotating on its own axis, the planting claws are moved back and forth between the seedling platform and the field, and the seedlings are scraped off one by one from the seedling mat and planted in the field. The operating cycle (planting cycle) of the planting claws in the seedling planting device is linked to the traveling speed of the traveling machine, and the planting interval (between plants) of seedlings is maintained constant even if the traveling speed changes.

The number of seedlings to be planted per unit area (generally 3.3 square meters) is not necessarily constant, and the desired number of seedlings to be planted per unit area varies depending on the region, user, etc., for example. In this regard, conventional rice transplanters are equipped with an inter-plant transmission device that adjusts the interlocking relationship between the traveling speed and the planting cycle. In this case, by changing the operating speed (planting speed) of the transplanting mechanism relative to the traveling speed using the inter-plant transmission, the inter-plant spacing is changed and the number of plants planted per unit area is changed.

In recent years, in consideration of the growth conditions of seedlings planted in the field, sparse planting has been carried out in which the spacing between plants is longer than standard planting, but the longer the spacing between plants, the slower the planting speed must be. However, simply slowing down the planting speed using the plant-to-plant transmission device causes the problem that the tips of the planting claws are dragged around the field, causing the seedlings to fall forward or floating seedlings to occur.

In this regard, Patent Documents 1 and 2 describe a rice transplanter equipped with an inconstant velocity member that transmits inconstant velocity rotational power to the transplanting mechanism in order to prevent the planting claws from being dragged in the field during sparse transplantation. structure is disclosed. The inconstant velocity member is configured to change the angular velocity (inconstant velocity rotation) during one rotation of the rotary case that constitutes the transplanting mechanism, and increases the speed at which the planting claws escape from the field even during sparse planting. There is. In the rice transplanter disclosed in Patent Document 1, an inconstant velocity member is incorporated in the inter-plant transmission device located within the transmission case. In the rice transplanter of Patent Document 2, an inconstant velocity member is provided on the downstream side of the power transmission side of the transverse feed drive mechanism of the seedling platform.

Patent No. 4376154 Japanese Patent Application Publication No. 2003-189712

Now, there are two types of power switching structures for inter-station transmissions: those that shift (switch) in stages and those that shift continuously, but all of them tend to have a large number of parts and a complicated structure. was there.

The present invention has been made in view of the above-mentioned current situation, and aims to prevent the disadvantages of the inconstant velocity member while enjoying the advantages thereof.

The rice transplanter according to one aspect of the present invention includes a seedling planting device supported by a running section, transmitting power to the seedling planting device, and performing work of the seedling planting device in response to a running speed of the running section. An inter-plant transmission device capable of changing speed, the inter-plant transmission device including an output shaft that transmits power to the seedling planting device, a plurality of transmission gears supported in parallel on the output shaft, A counter shaft provided in parallel to the output shaft, and a plurality of counter gears supported by the counter shaft and corresponding to each of the plurality of transmission gears, and one transmission gear among the plurality of transmission gears. By selecting a plurality of power transmission paths to the output shaft, the plurality of transmission gears include a plurality of outer transmission gears located on an end side in the axial direction of the output shaft; an inner transmission gear located between an outer transmission gear, both of which are configured to transmit a slower power to the seedling planting device than the inner transmission gear.

At least one of the plurality of outer transmission gears may be an inconstant speed gear.

A plurality of the inner transmission gears may be provided.

The inner transmission gear may include a constant velocity gear.

Incidentally, an inconstant speed gear is also arranged inside the rotary case that constitutes the transplanting mechanism, and this gear operates the planting claw so as to draw a long non-circular movement locus in the vertical direction. It is different from an inconstant velocity member (that is, a member that imparts inconstant velocity rotation (acceleration/deceleration) to a transmission element of a power transmission system).

According to the present invention, a power switching structure that tends to be complicated can be simplified in an interplant transmission device that can change the working speed of a seedling planting device with respect to the traveling speed of a traveling section.

FIG. 1 is a plan view of a rice transplanter according to an embodiment. It is a side view of a rice transplanter. It is a perspective view showing the frame of a rice transplanter. (A) is a perspective view showing the entire power transmission path, and (B) is a perspective view of the implantation mechanism. (A) is a side view of the power transmission path, (B) is a side view of the implantation mechanism, and (C) is a diagram showing the locus of the implanted nail. (A) is a plan view showing a power transmission path, (B) is an external perspective view of the interplant changing device, and (C) and (D) are external perspective views of a center case provided in the planting section. (A) is an external perspective view of the gear group in the stock change device and the center case, and (B) is a perspective view of the gear group in the center case. It is a transmission system diagram. (A) is a plan view showing a power transmission path to the planting device, (B) is an isolated plan view of the end planting portion of the power transmission path, and (C) is a schematic diagram of a bevel gear. (A) and (B) are plan views showing the meshing state of the bevel gears, (C) and (D) are perspective views of the bevel gears, and (E) is a comparative view of a pair of bevel gears arranged side by side. It is a chart showing the relationship between the gear combination in the inter-plant transmission device and the number of planted plants. It is a figure which shows the movement locus of a planting claw when setting to 43 plants of non-uniform speed. It is a figure which shows the angular velocity change of a planting claw when setting to 43 plants of non-uniform velocity. FIG. 3 is a plan view showing the arrangement structure of the transplantation mechanism in the first example. It is a plane sectional view showing a power transmission structure in a planting transmission case. It is an enlarged plan sectional view of the rear part of a planting transmission case. It is an enlarged side cross-sectional view of the rear part of the planting transmission case. FIG. 6 is a diagram showing the relationship between rotational torque and antiphase torque of the transplantation mechanism. It is a power transmission system diagram from the planting transmission case to the transplanting mechanism in the second embodiment. It is a power transmission system diagram from the planting transmission case to the transplanting mechanism in the third embodiment. It is a power transmission system diagram from the planting transmission case to the transplanting mechanism in the fourth embodiment. It is an explanatory view showing typically an inconstant velocity member in a 4th example. It is an explanatory view showing typically an inconstant velocity member in a 5th example. It is an explanatory view showing typically an inconstant velocity member in a 6th example. It is an explanatory view showing typically an inconstant velocity member in a 7th example. It is an explanatory view showing typically an inconstant velocity member in an 8th example. It is an explanatory view showing typically an inconstant velocity member in a 9th example.

Next, embodiments of the present invention will be described based on the drawings. The embodiment is applied to a riding type rice transplanter (hereinafter simply referred to as "rice transplanter"). In the following explanation, words such as "front and back" and "left and right" are used to specify the direction, but the words "front and rear" and "left and right" define the forward direction of the rice transplanter as the front. The front view direction is the direction opposite to the forward direction.

(1). Overview of the rice transplanter First, an overview of the rice transplanter will be explained based on Figures 1 to 5. As shown in FIGS. 1 to 3, the rice transplanter has a traveling body 1 and a seedling planting device 2 disposed behind it. The traveling body 1 has front and rear wheels 3, 4, a control seat 5, and a control handle 6, while the seedling planting device 2 has a seedling platform 7 on which a seedling mat is placed and a transplanting mechanism 8. The rice transplanter of the embodiment is an 8-row planting type, and therefore, eight seedling mat placement areas are formed on the seedling platform 7, and eight transplant mechanisms are provided at the rear of the seedling planting device 2. 8 are arranged in a horizontal row.

As shown in FIG. 3, the traveling body 1 has a frame 9 made of a large number of frame members, and an engine 10 is supported at the front part of the frame 9. A transmission case 11 is arranged behind the engine 10. As clearly shown in FIG. 4(A), a hydrostatic continuously variable transmission (HST) 12 is installed on the left side of the mission case 11. The information is transmitted to the machine (HST) 12. The engine 10 is covered with a bonnet 14. Further, a portion of the traveling body 1 excluding the bonnet 14 is covered with a vehicle body cover 15.

A front axle device 17 is attached to the left and right side surfaces of the mission case 11, and the front wheel 3 is attached to the front axle device 17. A rear axle case 18 is arranged behind the transmission case 11, and the rear wheel 4 is attached to a rear axle that projects sideways from the rear axle case 18. The transmission case 11 and the rear axle case 18 are connected by a longitudinal joint member 19. Two left and right rear columns 20 are attached to the rear axle case 18, and the upper ends of the rear columns 20 are fixed to left and right horizontally elongated rear frames 9a (see FIG. 3) that constitute the rear end of the frame 9. .

A link device 21 consisting of upper and lower link bodies (top link and lower link) is rotatably connected to the left and right rear columns 20, and a seedling planting device 2 is attached to the rear end of the link device 21. . The link device 21 can be rotated by a hydraulic cylinder (elevating cylinder) 22 connected to the joint member 19. Therefore, by expanding and contracting the hydraulic cylinder 22, the seedling planting device 2 is raised and lowered.

As can be easily understood from FIG. 4, power is transmitted from the inside of the transmission case 11 to the inside of the rear axle case 18 via the rear wheel drive shaft 23. The rotation of the rear wheel drive shaft 23 is transmitted to the rear wheels 4 via a gear group provided in the rear axle case 18. In the rice transplanter of the embodiment, the seedling planting device 2 is provided with a soil leveling rotor 24, and power is transmitted to the soil leveling rotor 24 through a rotor drive shaft 25 that projects backward from the rear axle case 18.

In the embodiment, an interplant transmission 26 is attached to the right side of the rear axle case 18, and power is transmitted from the mission case 11 to the interplant transmission 26 via a planting power transmission shaft 27. The rotation of the planting power transmission shaft 27 is speed-changed by a gear group built into the inter-plant transmission device 26, and is transmitted to the seedling planting device 2 by the PTO shaft 29.

The seedling planting device 2 has a left and right horizontally elongated main frame 28, and a center case 30 is fixed to approximately the middle part of the left and right sides of the main frame 28, and the power of the PTO shaft 29 is generated by a gear built in the center case 30. transmitted to the group. Four planting transmission cases 31 extending backward are fixed to the rear surface of the main frame 28, and a pair of left and right transplanting mechanisms 8 are rotatably attached to the rear side of the planting transmission cases 31.

A left and right horizontally elongated planting drive shaft 32 passes through the front side (base end side) of the planting transmission case 31, and the rotation of this planting drive shaft 32 drives the transplantation mechanism 8 (details will be described later). do). Further, power is transmitted to the planting drive shaft 32 from the PTO shaft 29 via a gear group built into the center case 30. A horizontally elongated transverse feed shaft 33 is also attached to the center case 30, and the rotation of the transverse feed shaft 33 causes the seedling platform 7 to move laterally one pitch at a time.

The seedling planting device 2 has a group of belts 34 on which seedling mats are placed, and the belts 34 are wound around a pair of upper and lower vertical feed shafts 35. When the seedling platform 7 moves completely to either the left or right, the vertical feed support shaft 35 rotates, and the seedling mat moves downward by one pitch.

As shown in FIG. 4(B), each transplant mechanism 8 has one rotary case 36 and planting claw members 37 rotatably provided at both ends of the rotary case 36, and the rotary case 36 rotates 1/2 Each time, the planting claw members 37 scrape and plant the seedlings. Further, the rotary case 36 is set to rotate 1/2 when the PTO shaft 29 rotates once. The rotational speed of the PTO shaft 29 is basically proportional to the traveling speed of the traveling body 1, but by changing the relationship between the traveling speed and the rotational speed of the PTO shaft 29 using the interplant transmission 26, seedlings can be planted. The interval (between plants) can be changed.

(2). Structure and power transmission structure of inter-stock transmission (upstream inconstant velocity member)
The details of the power transmission system from the inter-plant transmission 26 to the transplant mechanism 8 will be described below. First, the structure of the inter-stock transmission 26 and the power transmission structure thereof will be explained mainly based on FIGS. 6 to 8. The interlock transmission 26 has a front and rear interlock case 40 split into two parts as shown in FIG. 6(B), and a gear group as shown in FIGS. 6(A) and (C) is arranged inside the interlock case 40. .

An input shaft 41 and an output shaft 42 are arranged inside the interplant case 40, and the rear end of the planting power transmission shaft 27 is connected to the input shaft 41 via a universal joint. A first gear 43 and a second gear 44 having the same diameter are fixed to the input shaft 41. Both gears 43 and 44 have the same diameter, but the number of teeth in the second gear 44 is slightly smaller than that in the first gear 43.

The input shaft 41 and the output shaft 42 are arranged concentrically. A cylindrical intermediate shaft 45 is fitted to the input shaft 41 so as to be relatively rotatable, and the intermediate shaft 45 is fitted to rotate together with the output shaft 42 (in a state in which relative rotation is not possible). A third gear 46 and a fourth gear 47 are fitted to the intermediate shaft 45 by spline fitting or the like so that they can slide but cannot rotate relative to each other. Further, an upstream inconstant speed first gear 48 and an upstream inconstant speed third gear 121 are fitted to the intermediate shaft 45 so as to be relatively rotatable.

A cam type main clutch 49 is provided on the output shaft 42. The main clutch 49 consists of a fixed part 49a and a slide part 49b, and the slide part 49b is biased toward the fixed part 49a by a clutch spring 49c (see FIG. 7(C)). When the slide part 49b moves away from the fixed part 49a against the clutch spring 49c, power transmission from the input shaft 41 to the output shaft 42 is interrupted. The main clutch 49 is disengaged when the seedling planting device 2 is raised while driving on the road or turning. The main clutch 49 is disengaged by lowering the main clutch operating shaft 50.

An idle shaft 51 extending parallel to the input shaft 41 and the output shaft 42 when viewed from the side is rotatably supported inside the case 40, and the idle shaft 51 is connected to the first gear 43 or the second gear 44. A fifth gear 52 that can be meshed is fitted by spline fitting or the like so that it can slide and cannot rotate relative to the gear. The fifth gear 52 has about twice the number of teeth as the first gear 43 or the second gear 44, and can select a first position in which it meshes with the first gear 43 and a second position in which it meshes with the second gear 44. .

The idle shaft 51 has an upstream inconstant speed fourth gear 122 that is always in mesh with the upstream inconstant speed third gear 121, a sixth gear 54 that meshes with and disengages from the third gear 46, and a fourth gear that meshes with the fourth gear 47. - The separating seventh gear 55 and the upstream inconstant speed second gear 56, which always meshes with the upstream inconstant speed first gear 48, are fixed. The ratio of the number of teeth of the seventh gear 55 to the fourth gear 47 is set to be smaller than the ratio of the number of teeth of the sixth gear 54 to the third gear 46. Therefore, the rotation speed of the intermediate shaft 45 (and output shaft 42) is higher when the fourth gear 47 and the seventh gear 55 are engaged than when the third gear 46 and the sixth gear 54 are engaged. is lower.

The upstream inconstant velocity first gear 48 and the upstream inconstant velocity second gear 56 have a non-circular profile such as an ellipse, and have the same number of teeth. Therefore, in a state where the rotation of the idle shaft 51 is transmitted to the intermediate shaft 45 and the output shaft 42 via both inconstant speed gears 48 and 56, the rotation speeds of the idle shaft 51 and the output shaft 42 are the same, and , the output shaft 42 rotates with its angular velocity changing periodically during one rotation. Both inconstant velocity gears 48 and 56 are non-circular and are always maintained in a meshed state due to the special feature that the meshing phase is always determined. Similarly, the upstream inconstant velocity third gear 121 and the upstream inconstant velocity fourth gear 122 also have a non-circular profile such as an ellipse, and the number of teeth is set to be the same. Therefore, in a state where the rotation of the idle shaft 51 is transmitted to the intermediate shaft 45 and the output shaft 42 via both inconstant speed gears 48 and 56, the rotation speeds of the idle shaft 51 and the output shaft 42 are the same, and , the output shaft 42 rotates with its angular velocity changing periodically during one rotation. That is, the upstream inconstant velocity first gear 48 and the upstream inconstant velocity second gear 56 are a non-circular gear pair such as an eccentric gear, and have a large acceleration/deceleration ratio (inconstant velocity ratio). The upstream inconstant speed third gear 121 and the upstream inconstant speed fourth gear 122 are also non-circular gear pairs such as eccentric gears, but have a small acceleration/deceleration ratio (inconstant speed ratio).

Here, in the rotary case 36, for example, when sparsely planting 37 plants/m2, the maximum speed phase of each planting claw 96 in the planting claw member 37 (the phase at which the operating speed of the planting claw 96 becomes the highest) is set. Although acceleration/deceleration is applied to bring the position near the bottom dead center, in the embodiment, the upstream inconstant speed first gear 48 and the upstream inconstant speed second gear 56 provided in the inter-stock transmission 26 provide Slightly larger acceleration/deceleration is applied to the rotational power from the case 40 between the stumps to output inconstant rotational power. Therefore, since the acceleration/deceleration ratio (inconstant velocity ratio) is larger than the combination of the upstream inconstant velocity third gear 121 and the upstream inconstant velocity fourth gear 122, the position near the bottom dead center of the operation trajectory of the planting claw 96 greatly increases the operating speed of Further, the upstream inconstant velocity third gear 121 and the upstream inconstant velocity fourth gear 122 apply a slightly smaller acceleration/deceleration to the rotational power from the inter-plant case 40 to output inconstant velocity rotational power. Therefore, since the acceleration/deceleration ratio (inconstant velocity ratio) is smaller than the combination of the upstream inconstant velocity first gear 48 and the upstream inconstant velocity fourth gear 56, the movement trajectory of the planting claw 96 near the bottom dead center Increase the operating speed by a small amount. The upstream inconstant speed first to fourth gears 48, 56, 121, and 122 correspond to upstream inconstant speed members on the interplant transmission 26 side that transmit inconstant rotational power to the transplantation mechanism 8.

The fourth gear 47 and the upstream inconstant speed first gear 48 are provided with a first intermediate clutch 57 that can engage and disengage freely. When the fourth gear 47 is once engaged with the seventh gear 55 from the state shown in FIG. 8 and further slides to the right, the first intermediate clutch 57 is engaged. When the first intermediate clutch 57 is engaged, the power of the idle shaft 51 is transmitted to the output shaft 42 via the upstream inconstant speed second gear 56 and the upstream inconstant speed first gear 48 . When the first intermediate clutch 57 is engaged, the third gear 46 and the fourth gear 47 are idle. Therefore, the first intermediate clutch 57 functions to connect and disconnect the intermediate shaft 45 and the upstream inconstant speed first gear 48 .

Further, the third gear 46 and the upstream inconstant speed third gear 121 are also provided with a second intermediate clutch 123 that can engage and disengage freely. When the third gear 46 is once engaged with the sixth gear 54 from the state shown in FIG. 8 and further slides leftward, the second intermediate clutch 123 is engaged with the intermediate shaft 45. When the second intermediate clutch 123 is engaged, the power of the idle shaft 51 is transmitted to the output shaft 42 via the upstream inconstant speed fourth gear 122 and the upstream inconstant speed third gear 121. Also in this case, if the second intermediate clutch 123 is engaged, the third gear 46 and the fourth gear 47 will idle. Therefore, the second intermediate clutch 123 functions to connect and disconnect the intermediate shaft 45 and the upstream inconstant speed third gear 121.

When the fifth gear 52 slides, two-stage switching is performed, and when the intermediate shaft 45 slides, four-stage switching is performed. Therefore, there are a total of eight combinations (speed switching). For example, the number of plants per 3.3 square meters can be changed from 37 to 85, covering almost all areas of sparse planting and dense planting. FIG. 11 shows the relationship between the gear combination and the number of plants to be planted in the embodiment. When the first gear 43 and the fifth gear 52 are engaged, if the fourth gear 47 and the seventh gear 55 are engaged, the number of plants to be planted is set to d at a constant speed, and the third gear 46 and the sixth gear are engaged. When engaged with the gear 54, the number of plants to be planted is set to f plants at a constant speed. When the second intermediate clutch 123 is engaged, the number of plants to be planted is set to b plants with non-uniform speed. When the second gear 44 and the fifth gear 52 are engaged, if the fourth gear 47 and the seventh gear 55 are engaged, the number of plants to be planted is set to constant-velocity c plants, and the third gear 46 and the sixth gear are engaged. When engaged with the gear 54, the number of plants to be planted is set to constant speed e. When the first intermediate clutch 57 is engaged, the number of plants to be planted is set to a non-uniform speed. In this case, the number of stocks indicated by alphabets is larger in alphabetical order.

Here, the upstream inconstant speed first to fourth gears 48, 56, 121, 122 can be assembled to the intermediate shaft 45 or the idle shaft 51 by adjusting the mounting phase, thereby controlling the movement of the planting claw 96 in the transplanting mechanism 8. The maximum speed phase at which the speed reaches its maximum speed can be set and changed in the range before and after the bottom dead center. As an example, FIG. 12 shows the movement locus of the planting claws 96 when 43 plants are set at non-uniform speeds. The symbol MS1 in FIG. 12 indicates that the upstream inconstant speed third gear 121 and the upstream inconstant speed fourth gear 122 are set so that the operating speed of the planting claw 96 is the highest before the bottom dead center (on the upstream side). This is the highest speed phase when assembled, and MS2 is the upstream inconstant speed third gear 121 and the upstream inconstant speed fourth gear 122 so that the operating speed of the planting claw 96 becomes the maximum speed near the bottom dead center. This is the maximum speed phase when assembled. Symbol MS3 indicates that an upstream inconstant speed third gear 121 and an upstream inconstant speed fourth gear 122 are assembled so that the operating speed of the planting claw 96 is the highest on the rear side (downstream side) of the bottom dead center. This is the highest speed phase for the case.

Depending on the relationship with assembly accuracy, for example, the upstream inconstant speed third gear 121 and the upstream inconstant speed fourth gear 122 may be assembled so that the highest speed phase MS1 is on the front side (upstream side) of the bottom dead center. , the upstream inconstant speed third gear 121 and the upstream inconstant speed fourth gear 122 are assembled so that the highest speed phase MS2 is set near the bottom dead center, and furthermore, the maximum speed is set at the rear (downstream side) of the bottom dead center. It is possible to assemble the upstream inconstant velocity third gear 121 and the upstream inconstant velocity fourth gear 122 so as to set the phase to MS3. That is, for example, in relation to assembly accuracy, there may be cases where the power transmission system has a large torsion and there is a concern that the operation cycle of the planting claw 96 may shift, or when the power transmission system has a small torsion and the vibration of the power transmission system is minimized. If you want to suppress it, you can change the setting of the maximum speed phase to around bottom dead center. By doing so, it is possible to suppress so-called "shaking" of the planting claws 96 and to suppress vibrations of the power transmission system. It goes without saying that the upstream inconstant velocity first gear 48 and the upstream inconstant velocity second gear 56 may be assembled to the intermediate shaft 45 or the idle shaft 51 by adjusting the mounting phase.

A rotary shaft 58 for fertilization that extends parallel to the input shaft 41 and the output shaft 42 is rotatably arranged in the upper part of the case 40 between plants. A gear 59 is fitted so as to be relatively rotatable. Power is transmitted from the fertilizing rotating shaft 58 to a fertilizing drive shaft 62 via a bevel gear 61.

As shown in FIG. 7(A), the inter-stock transmission 26 has two operating shafts, a first operating shaft 63 and a second operating shaft 64. These operating shafts 63 and 64 are in longitudinal longitudinal postures, and are exposed in front of the case 40 between the plants. As can be understood from FIG. 6(B), the first operating shaft 63 can be slid back and forth with the first lever 65, and the second operating shaft 64 can be slid back and forth with the second lever 66. The first operation shaft 63 is for slidingly operating the fifth gear 52, and has a shifter for sliding the fifth gear 52. The second operating shaft 64 is for slidingly operating the intermediate shaft 45 and includes a shifter that engages with the intermediate shaft 45.

(3). Internal Structure of Center Case Next, the internal structure of the center case 30 (ie, the planting section transmission device) will be described based on FIGS. 6 to 8. The center case 30 consists of a shell body divided into left and right halves, and a front and rear longitudinal input shaft 69 is rotatably held therein. The front end of the input shaft 69 and the rear end of the PTO shaft 29 are connected via a universal joint.

A left and right longitudinal intermediate shaft 70 is disposed inside the center case 30, and rotation of the input shaft 69 is transmitted to the intermediate shaft 70 by a pair of first bevel gears 71a and 71b. Inside the center case 30, a transverse feed shaft 72 is disposed in a left-right and laterally elongated posture, and a transverse feed shaft 33 is connected to the transverse feed shaft 72.

Three transverse feed amount adjustment driven gears 73 are fixed to the transverse feed drive shaft 72, while three transverse feed amount adjustment driven gears 73 are fixed to the intermediate shaft 70 in correspondence with the transverse feed amount adjustment driven gears 73. 74 is loosely fitted. Power is selectively transmitted from the intermediate shaft 70 to only one of the three lateral feed adjustment main drive gears 74 by a slide key 76 (see FIG. 8). The slide key 76 is slid by a slide lever 77 shown in FIGS. 6C and 7D and 7A and 7B.

The pairs of lateral feed adjustment gears 73 and 74 have different ratios of the number of teeth, and changing the combination of the lateral feed adjustment gears 73 and 74 changes the rotation ratio of the lateral feed drive shaft 72 to the PTO shaft 29. . As a result, the lateral feeding pitch of the seedling mounting table 7 changes, and the amount of seedlings to be scraped changes.

The center case 30 has an overhanging portion 30a extending rearward and downward, and a horizontally elongated planting output shaft 78 is rotatably held on this overhanging portion 30a. a first relay gear 79 fixed to, a second relay gear 80 relatively rotatably fitted to the traverse drive shaft 72, a third relay gear 82 rotatably held to the center case 30 via an idle shaft 81, Power is transmitted via the fourth relay gear 84. The fourth relay gear 84 is attached to the planting output shaft 78 via a sleeve 83.

The ratio of the number of teeth of the first bevel gears 71a, 71b is 1:1, and the number of teeth of the first relay gear 79, second relay gear 80, and fourth relay gear 84 is 1:1:1. In a relationship. Therefore, the rotational speeds of the PTO shaft 29 and the planting output shaft 78 have a 1:1 relationship. Note that since the third relay gear 82 is a mere idle gear, its number of teeth does not affect the rotation speed of the fourth relay gear 84.

The planting output shaft 78 and the planting drive shaft 32 located next to it are connected by a coupling (sleeve) 86. Further, a relay shaft 85 is arranged between the planting drive shafts 32 adjacent to each other on the left and right, and the drive shaft 32 and the relay shaft 85 are also connected by a coupling 86. Therefore, each planting drive shaft 32 rotates integrally. The planting drive shaft 32 is divided into parts for each transplant mechanism 8, and adjacent planting drive shafts 32 are connected by a pull 86. In addition, it is also possible to make the planting output shaft 78, each planting drive shaft 32, and the relay shaft 85 into a single structure which consists of one bar material.

(4). Structure of Implantation Mechanism/Power Transmission Structure Next, the structure of the implantation mechanism 8 and the power transmission structure thereof will be explained. These constitute the main parts of the embodiment and are mainly displayed in FIGS. 8 to 10 (see also FIG. 6(A)). The planting transmission case 31 has a hollow structure, and as shown in FIG. 8, a longitudinal planting transmission shaft 87 is rotatably held inside thereof.

Power is transmitted to the planting transmission shaft 87 from the planting drive shaft 32 through a second bevel gear pair 88a, 88b. Of the second bevel gear pair 88a, 88b, a bevel gear 88b that rotates concentrically with the planting transmission shaft 87 is attached to a torque limiter 89 fitted to the planting transmission shaft 87. The torque limiter 89 has a spring 90, and when a predetermined load or more is applied to the planting transmission shaft 87, the mesh is disengaged and power transmission is interrupted.

A laterally elongated planting center shaft 91 is rotatably held on the rear side (tip side) of the planting transmission case 31 via a pair of left and right bearings 104 . The planting center shaft 91 projects to the left and right outside of the planting transmission case 31, and a sun gear 92 built in the rotary case 36 is fixed to the projecting end. Although details are omitted, the rotary case 36 is rotatably held at the rear end of the planting transmission case 31.

The rotary case 36 has a hollow structure in which two left and right shell bodies are stacked one on top of the other, and the aforementioned sun gear 92 is arranged in the longitudinal middle part, the intermediate gear 93 is arranged outside the sun gear 92, and the planetary gear is arranged outside the sun gear 92. A gear 94 is arranged. Each gear 92, 93, 94 is non-circular and eccentric. The planting claw member 37 is fixed to a unit shaft 95 fixed to the planetary gear 94.

As clearly shown in FIG. 5, the planting claw member 37 includes a planting claw 96 and a protruding rod 97, and as shown in FIG. The seedlings are planted in the field by cutting off the seedlings and transferring them to the field, and the protruding rod 97 moves forward relative to the planting claw 96 near the bottom dead center.

As shown in FIG. 9, power is transmitted from the planting transmission shaft 87 to the planting center shaft 91 by a pair of downstream inconstant velocity bevel gears 98 and 99. That is, a downstream inconstant velocity active bevel gear 98 is fixed to the planting transmission shaft 87 via a coupling 100, while a downstream inconstant velocity driven bevel gear 99 is fitted to the planting center shaft 91. Inconstant velocity rotation is transmitted from the planting transmission shaft 87 to the planting center shaft 91 by the inconstant velocity bevel gear pair 98 and 99.

The downstream inconstant velocity active bevel gear 98 has a stepped boss body 98a, and the coupling 100 is fitted into the small diameter portion of the boss body 98a. A bearing 101 is fitted into the boss body 98a. Note that the coupling 100 is welded and fixed to the planting power transmission shaft 87 and is held so as not to be relatively rotatable. The downstream inconstant velocity driven bevel gear 99 is fitted to the planting center shaft 91 so as to be relatively rotatable, and has a cam portion 103 that engages with the row stop clutch 102 . An operating ring 105 is integrally welded to the stop clutch 102 .

The row stop clutch 102 is slidable on the planting center shaft 91 and is held relatively unrotatably. The row stop clutch 102 is normally pressed by a spring 106 into a state of meshing with the downstream inconstant velocity driven bevel gear 99. When the operating rod 129 is operated, the row stop clutch 102 moves away from the downstream inconstant velocity driven bevel gear 99 along the axis of the planting center shaft 91, and the power to the planting center shaft 91 is cut off.

For example, in planting work at the edge of a ridge, there may be cases where you do not want to operate some of the four pairs of transplanting mechanisms 8; function can be stopped. In other words, a row-stopping function that reduces the number of planted rows is exhibited.

(5). Downstream Inconstant Velocity Member In the embodiment, the downstream inconstant velocity bevel gear pair 98, 99 has a function of rotating at an inconstant velocity (acceleration/deceleration). ). This point will be explained mainly based on FIG. 10 and FIG. 9(C). As shown in FIG. 10(E), when forming a large number of teeth 107 on the downstream inconstant velocity active bevel gear 98, the distance from the tip of each tooth 107 to the axis O1 is set to gradually widen and narrow again. are doing. That is, each tooth 107 has a minimum pitch cone angle portion 108 where the distance from the axis O1 to the tip is the narrowest, and a maximum pitch cone angle portion 109 where the distance from the axis O1 to the tip is the widest, The interval between the two is gradually changing.

In other words, as shown in FIG. 9(C), the pitch circle 110 of each tooth 107 has a shape close to an ellipse and is eccentric with respect to a perfect circle (numeral 110' indicates the pitch circle in the case of a perfect circle). ing). From the opposite perspective, in a normal bevel gear, the outer circumferential surface of the virtual cone is inclined at the same angle with respect to the axis at any part, but in the downstream inconstant velocity active bevel gear 98 of the embodiment, the outer peripheral surface of the virtual cone is inclined at the same angle with respect to the axis. As the outer circumferential surface of the cone moves in the circumferential direction, the inclination angle θ1 (see FIGS. 10A and 10C) of the outer circumferential surface is gradually changed.

The downstream inconstant velocity driven bevel gear 99 has twice the number of teeth 112 as the downstream inconstant velocity driving bevel gear 98 . As can be clearly seen from FIGS. 10(A) and 10(B), the positions of the teeth 112 in the axial direction are slightly shifted. In other words, in the downstream inconstant velocity driven bevel gear 99 of the embodiment, as the outer circumferential surface of the virtual cone moves in the circumferential direction, the inclination angle θ2 of the outer circumferential surface (FIG. 10 (See (A)) are gradually changed.

Since the downstream inconstant velocity driven bevel gear 99 has twice the number of teeth as the downstream inconstant velocity main driving bevel gear 98, the downstream inconstant velocity driven bevel gear 99 has two maximum pitch cone angle portions 113 and two minimum pitch cone angle portions. It has a section 114. Therefore, as shown in FIG. 9(C), the pitch circle 115 of the downstream inconstant velocity driven bevel gear 99 has a substantially elliptical shape, and is symmetrical with respect to the axis O2 (FIG. 9(C) ), the pitch circle in the case of a perfect circle is indicated by the symbol 115'). In other words, the downstream inconstant velocity bevel gear pair 98, 99 continuously changes the pitch cone angles θ1, θ2 along the rotation direction while keeping the cone distance γ (see FIG. 10(C)) constant. It is. As can be seen from the above description, the downstream inconstant velocity bevel gear pair 98, 99 as the downstream inconstant velocity member is a single stage, and the upstream inconstant velocity first to fourth gears 48, 56 as the upstream inconstant velocity member , 121, and 122 (there is no speed switching).

In this way, the pitch circles 110, 115 of the downstream inconstant velocity bevel gears 98, 99 are shaped close to ellipses and are eccentric to the perfect circle centered on the rotation axes O1, O2, and the outer diameter shape is By making each of the pairs of downstream inconstant velocity bevel gears 98 and 99 perfectly circular, each pair of downstream inconstant velocity bevel gears 98 and 99 can be formed to the same size as a normal bevel gear, and the assembly space for the downstream inconstant velocity bevel gears 98 and 99 pair in the power transmission system is reduced. can be made smaller and more compact. In this case, the idea of manufacturing the downstream inconstant velocity bevel gears 98 and 99 is to cut a distorted conical shape formed with a constant conical distance using a cylinder with common rotational axes O1 and O2, and then make the outer diameter shape into a true shape. This means making it a yen.

Here, the mounting phase of the downstream inconstant velocity bevel gear pair 98, 99 is also adjusted in the same way as the upstream inconstant velocity first to fourth gears 48, 56, 121, 122, and the above-mentioned maximum speed phase is adjusted to the bottom dead center. The setting can be changed further away from the target. As an example, FIG. 13 shows changes in the angular velocity of the planting claws 96 when 43 plants are set at non-uniform speeds. The thick dashed-dotted line in FIG. 13(A) indicates the state in which the upstream inconstant speed third gear 121 and the upstream inconstant speed fourth gear 122 are assembled so that the front side (upstream side) of the bottom dead center is the highest speed phase MS1. This is the case where the downstream inconstant velocity bevel gear pair 98, 99 is assembled so that the maximum speed phase MS1' (see FIG. 12) is located further ahead of the bottom dead center. The thick solid line in FIG. 13(B) indicates that the upstream inconstant velocity third gear 121 and the upstream inconstant velocity fourth gear 122 are assembled so that the maximum speed phase MS2 is near the bottom dead center, and the downstream inconstant velocity bevel gear pair is assembled. This is the case when 98 and 99 are assembled. The thick two-dot chain line in FIG. 13(C) indicates that the upstream inconstant speed third gear 121 and the upstream inconstant speed fourth gear 122 are assembled so that the maximum speed phase MS3 is on the rear side (downstream side) of the bottom dead center. In addition, the downstream inconstant velocity bevel gear pair 98, 99 is assembled so that the highest speed phase MS3' (see FIG. 12) is located behind the bottom dead center. With this configuration, the operating speed of the planting claw 96 increases near the bottom dead center, and the effect of allowing the planting claw 96 to accurately and quickly escape from the bottom dead center can be further promoted.

(6). Summary FIG. 5C shows the relationship between the number of plants planted per 3.3 square meters and the movement locus of the planting claws 96. As can be understood from this figure, even if the planting claws 96 rise directly above from the bottom dead center during dense planting, the escape of the planting claws 96 becomes difficult when planting sparsely, causing a phenomenon in which the seedlings are brought forward. It can be understood.

In the embodiment, the interplant transmission device 26 is provided with upstream inconstant speed first to fourth gears 48, 56, 121, 122, and the seedling planting device 2 is provided with downstream inconstant speed bevel gear pairs 98, 99. Due to this provision, the planting claw member 37 is accelerated and rotationally driven so that the operating speed becomes faster near where the planting claw 96 is located at the bottom dead center. For this reason, the planting claw 96 quickly escapes from the bottom dead center, and as a result, it is possible to prevent the planting claw 96 from tipping the seedling forward.

In the embodiment, since the inconstant velocity member is arranged separately in the interplant transmission device 26 and the seedling planting device 2, the distance between the interplant transmission device 26 and the downstream inconstant velocity bevel gear pair 98, 99 is compared to the conventional one. Therefore, the proportion of non-uniform rotation is small. As a result, twisting occurring in the transmission elements (PTO shaft 29, planting drive shaft 32, planting transmission shaft 87, etc.) constituting the power transmission system is significantly suppressed, and smooth movement of the transplantation mechanism 8 can be ensured. Furthermore, since it is possible to suppress backlash that occurs in the power transmission system, it is also possible to prevent problems such as the timing of uneven speeds being shifted and the planting posture of seedlings being disturbed.

Now, since the transplanting mechanism 8 has a structure in which the planting claw members 37 are swingably attached to both ends of the elongated rotary case 36, the planting claw members 37 themselves serve as a weight and generate a large inertial force. Moreover, a large load is generated when the seedlings are scraped, and a negative load is generated thereafter. That is, due to the swinging of the planting claw member 37, large torque fluctuations occur in the rotation of the transplantation mechanism 8 in cycles such as overload → no load → negative load. Such torque fluctuations become noticeable when the resonant rotation speed is exceeded even if the rotation speed is constant during dense planting (this is because the transplanting mechanism 8 rotates at a higher speed during dense planting than when sparse planting).

More specifically, even if the transplanting mechanism 8 rotates at a constant speed, when one planting claw member 37 escapes from the field, the other planting claw member 37 shifts to scraping the seedlings. It can be said that the planting claw members 37 act to cancel each other's load fluctuations. However, since a large torque is required to scrape off seedlings, the function of leveling out torque fluctuations by only moving the two planting claw members 37 is weak. For this reason, the transplantation mechanism 8 does not rotate smoothly, and a phenomenon called "shikuri" is likely to occur.

On the other hand, if a slight inconstant rotation is applied to the transplanting mechanism 8 by the downstream inconstant velocity bevel gear pair 98 and 99 even in a densely planted state as in the embodiment, the scraping of the seedlings by the planting claw member 37 is caused by inertia. Since the transplanting mechanism 8 is decelerated after the seedlings have been scraped off, it is possible to suppress a large inertial force from acting on the transplanting mechanism 8. Therefore, load fluctuations (or torque fluctuations) acting on the transplantation mechanism 8 can be leveled out to ensure smooth rotation.

(7). First Example of Anti-Phase Torque Generating Member Next, a first example of the anti-phase torque generating member 130 will be described with reference to FIG. 8 and FIGS. 14 to 18. The rice transplanter of the embodiment has an inverse phase that is opposite to the rotational torque T of the transplanting mechanism 8 based on the inconstant rotational power of the upstream inconstant velocity and downstream inconstant velocity bevel gear pair 98, 99. It includes an anti-phase torque generating member 130 that adds phase torque Tan. In the first embodiment, an opposite phase torque generating member 130 is provided in each of the plurality of (four) planting transmission cases 31. Since each planting transmission case 31 is provided with a row stop clutch 102, there is an opposite phase torque generating member 130 for each combination of a total of four planting transmission cases 31 and row stop clutches 102.

As shown in FIGS. 14 to 17, an end case 131 having a hollow structure is integrally provided on the rear end side of the planting transmission case 31. Note that the end case 131 may be a separate structure that is detachably attached to the rear end side of the planting transmission case 31. The inside of the planting transmission case 31 and the inside of the end case 131 are in communication. A longitudinal planting branch shaft 132 is rotatably supported via a bearing at a communication location between the inside of the planting transmission case 31 and the inside of the end case 131. A leveling bevel gear 133 that constantly meshes with the downstream inconstant velocity driven bevel gear 99 is provided on the front end side of the planting branch shaft 132. The leveling bevel gear 133 and the downstream inconstant-velocity active bevel gear 98 are in a positional relationship in which they face each other across the planting center axis 91 (opposing each other).

The leveling bevel gear 133 is formed in the same shape as the downstream inconstant velocity active bevel gear 98. That is, the leveling bevel gear 133 has the same number of teeth as the downstream inconstant velocity active bevel gear 98, and similarly to the downstream inconstant velocity active bevel gear 98, the pitch cone angle is adjusted in the rotation direction with the cone distance kept constant. It is formed into a shape that changes continuously along the line. Therefore, the leveling bevel gear 133 and by extension the planting branch shaft 132 rotate in the opposite direction at the same speed as the downstream inconstant velocity active bevel gear 98 (rotate at twice the speed as compared to the downstream inconstant velocity driven bevel gear 99). .

The rear end side of the planting branch shaft 132 protrudes in the middle of the upper and lower parts of the end case 131. An eccentric shaft 134 extending parallel to the planting branch shaft 132 is fixed to the protrusion on the rear end side. The axial center of the eccentric shaft 134 is eccentric with respect to the rotation center of the planting branch shaft 132. For this reason, the planting branch shaft 132 and the eccentric shaft 134 have a crankshaft shape (exhibiting the function of a crankshaft). A locking pin 135 is attached to the lower side of the end case 131. A tension spring 136 is mounted on the eccentric shaft 134 and the locking pin 135 as means for generating an antiphase torque. The tension spring 136 constantly biases the eccentric shaft 134 in a direction to move it below the planting branch shaft 132. When the eccentric shaft 134 passes directly above the planting branch shaft 132, the tension spring 136 is set so as to pass over the fulcrum. In the first embodiment, the planting branch shaft 132, the eccentric shaft 134, and the tension spring 136 constitute the antiphase torque generating member 130.

Note that a drive spur gear 137 is fixed to a protrusion on the rear end side of the planting branch shaft 132. A power take-off shaft 138 extending parallel to the planting branch shaft 132 is rotatably supported on the upper side of the end case 131 . A driven spur gear 139 is fixed to the front side of the power take-off shaft 138. A driving spur gear 137 and a driven spur gear 139 are always meshed. The rear end side of the power take-off shaft 138 projects rearward from the rear surface of the end case 131. The rotational power of the planting transmission shaft 87 is transmitted to the power extraction shaft 138 via the downstream inconstant velocity bevel gear pair 98, 99, the leveling bevel gear 133, the planting branch shaft 132, the drive spur gear 137, and the driven spur gear 139. be done. When an optional device such as a chemical sprayer is attached to the seedling planting device 2, the rotational power of the power output shaft 138 is transmitted to the optional device.

Here, FIG. 18 shows, as an example, the relationship between the rotational torque T (fluctuation torque) of the planting central axis 91 in the transplantation mechanism 8, the antiphase torque Tan, and the composite torque Tco that combines these. The one-dot chain line in FIG. 18 represents the rotational torque T (fluctuation torque) of the central planting axis 91, and the rotational torque T is around the bottom dead center where each planting claw 96 of the planting claw member 37 plants the seedling. becomes the largest. The two-dot chain line in FIG. 18 represents the reverse phase torque Tan generated by the reverse phase torque generating member 130 (planting branch shaft 132, eccentric shaft 134, and tension spring 136), and represents each planting claw of the planting claw member 37. Near the bottom dead center where 96 plants the seedling, the anti-phase torque Tan becomes the smallest.

The elastic restoring force of the tension spring 136 is transmitted from the leveling bevel gear 133 provided on the planting branch shaft 132 to the planting center shaft 91 via the downstream inconstant velocity driven bevel gear 99. As a result, as shown by the solid line in FIG. 18, the rotational torque T and the antiphase torque Tan are combined, and the combined torque Tco is transmitted to the transplantation mechanism 8. That is, the rotational torque T leveled (cancelled) by the combination of the antiphase torques Tan is transmitted to the transplantation mechanism 8. Therefore, load fluctuations (which may also be called torque fluctuations) acting on the transplantation mechanism 8 are leveled out, and smooth rotation of the transplantation mechanism 8 can be ensured. Therefore, the occurrence of a phenomenon called "shikuri" can be suppressed, and seedlings can be planted in an appropriate planting posture.

As is clear from the above description and FIGS. 8 and 14 to 18, the transmission case 11 that changes the speed of the power of the engine 10 mounted on the traveling aircraft 1 and the planting claw 96 that draws a non-circular motion trajectory are included. a seedling transplanting device 2 having a transplanting mechanism 8; In a rice transplanter including inconstant velocity members 98 and 99 that transmit rotational power, the rotational torque T of the transplanting mechanism 8 based on the inconstant velocity rotational power is in an opposite phase to the rotational torque T. Since the anti-phase torque generating member 130 is further provided, the anti-phase torque Tan from the anti-phase torque generating member 130 is equal to the rotational torque of the transplantation mechanism 8 caused by the inconstant rotational power. T is canceled out, and load fluctuations (which may also be referred to as torque fluctuations) acting on the transplantation mechanism 8 are leveled out, and smooth rotation of the transplantation mechanism 8 is ensured. Therefore, the occurrence of a phenomenon called "shikuri" can be suppressed, and seedlings can be planted in an appropriate planting posture.

In particular, the power transmission system from the inter-stock transmission 26 to the transplantation mechanism 8 includes rotating shafts 87 and 91 that intersect with each other, and these intersecting rotating shafts 87 and 91 are configured to transmit power via a pair of bevel gears. , the bevel gear pair is configured as an inconstant velocity gear pair 98, 99 as the inconstant velocity member, and the opposite phase torque generating member 130 is provided on the downstream inconstant velocity gear 99 of the inconstant velocity gear pair 98, 99. Since they are connected, the existing members of the inconstant velocity gear pair 98 and 99 can be used, which is advantageous in terms of cost.

(8). Second and Third Examples of Antiphase Torque Generating Member Next, a second example of the antiphase torque generating member 130 will be described with reference to FIG. In the second embodiment, the end case 131 is removed from the rear end side of the planting transmission case 31, and the opposite phase torque generating member 130 is arranged on the rear side inside the planting transmission case 31. This is different from the example.

In this case, external teeth 141 are formed on the outer peripheral side of the operating ring 105 of the row stop clutch 102. The external teeth 142 of the operating ring 105 mesh with a leveling spur gear 143 rotatably supported on the rear side within the planting transmission case 31. The rotation center axis 144 of the leveling flat gear 143 extends parallel to the planting center axis 91. A locking pin 145 is provided upright on one side of the leveling flat gear 143.

A tension spring 146 is mounted on the locking pin 145 and the inner circumferential wall of the planting transmission case 31 as a means for generating opposite phase torque. The tension spring 146 constantly biases the locking pin 145 in a direction away from the operating ring 105. The rotation of the leveling flat gear 143 causes the tension spring 146 to expand and contract. The leveling flat gear 143 and the tension spring 146 have a kind of crank structure. In the second embodiment, the operating ring 105 of the row stop clutch 102, the leveling spur gear 143, the locking pin 145, and the tension spring 146 constitute the opposite phase torque generating member 130. In other words, the opposite phase torque generating member 130 is located downstream of the row stop clutch 102 in the planting transmission case 31 . In addition, in the second embodiment, as in the case of the first embodiment, there is an opposite phase torque generating member 130 for each of the four combinations of planting transmission cases 31 and row stop clutches 102.

When configured as described above, the elastic restoring force of the tension spring 146 is transmitted from the leveling spur gear 143 to the planting center shaft 91 via the operation ring 105 of the row stop clutch 102. As a result, as in the case of the first embodiment (as shown by the solid line in FIG. 18), the rotational torque T and the anti-phase torque Tan are combined, the combined torque Tco is transmitted to the transplantation mechanism 8, and the rotational torque Tco is transmitted to the transplantation mechanism 8. 8 to ensure smooth rotation. Therefore, as in the case of the first embodiment, the occurrence of the phenomenon called "shikuri" can be suppressed, and the seedlings can be planted in an appropriate planting posture.

Furthermore, since the anti-phase torque generating member 130 is disposed downstream of the row stop clutch 102 in the planting transmission case 31, the anti-phase torque generating member 130 is located near the transplanting mechanism 8, which is the source of load fluctuations. will be located. Therefore, the effect of canceling out the rotational torque T of the transplantation mechanism 8 with the antiphase torque Tan, that is, the effect of leveling out load fluctuations is high. Moreover, since the opposite phase torque Tan is not generated when the row stop clutch 102 is in the power cutoff state, there is no risk of unnecessary torque being propagated around the transplantation mechanism 8.

FIG. 20 shows a third embodiment of the anti-phase torque generating member 130. The third embodiment shown in FIG. 20 is a modification of the second embodiment described above. The third embodiment is similar to the second embodiment in that an opposite phase torque generating member 130 is disposed on the rear side of the planting transmission case 31 and downstream of the row stop clutch 102. This embodiment is different from the second embodiment in that an opposite phase torque generating member 130 is provided separately from the row stop clutch 102.

In this case, the first leveling spur gear 152 is fixed to the planting center axis 91 on the opposite side of the row stop clutch 102 across the downstream inconstant velocity driven bevel gear 99. The first leveling flat gear 152 meshes with a second leveling flat gear 153 rotatably supported on the rear side of the planting transmission case 31 . The rotation center axis 154 of the second leveling flat gear 153 extends parallel to the planting center axis 91 . A locking pin 155 is provided upright on one side of the second flat gear 153 for leveling.

A tension spring 156 is mounted on the locking pin 155 and the inner circumferential wall of the planting transmission case 31 as a means for generating opposite phase torque. The tension spring 156 constantly biases the locking pin 155 in a direction away from the first flat gear 152 for leveling. The rotation of the second leveling flat gear 153 causes the tension spring 156 to expand and contract. The second leveling flat gear 153 and the tension spring 156 have a kind of crank structure. In the third embodiment, the first and second leveling spur gears 152 and 153, the locking pin 155, and the tension spring 156 constitute the antiphase torque generating member 130. In the third embodiment as well, there is an opposite phase torque generating member 130 for each combination of a total of four planting transmission cases 31 and row stop clutches 102. Even when configured as described above, the same effects as in the second embodiment can be achieved.

As is clear from the above embodiment and FIGS. 19 and 20, the transmission case 11 that changes the speed of the power of the engine 10 mounted on the traveling aircraft 1, and the transplant with the planting claw 96 that draws a non-circular motion trajectory a seedling planting device 2 having a mechanism 8; an inter-plant transmission device 26 that changes the operating speed of the transplanting mechanism 8 relative to the traveling speed of the traveling body 1 to change the spacing between plants; In the rice transplanter, the rice transplanter is equipped with inconstant velocity members 98 and 99 that transmit the rotational torque T of the transplantation mechanism 8 based on the inconstant velocity rotational power, and the rotational torque T is opposite in phase to the rotational torque T. Since the anti-phase torque generation member 130 that adds the phase torque Tan is further provided, the anti-phase torque Tan from the anti-phase torque generation member 130 increases the rotational torque T of the transplantation mechanism 8 caused by the inconstant rotational power. As a result, load fluctuations (which may also be referred to as torque fluctuations) acting on the transplantation mechanism 8 are leveled out, and smooth rotation of the transplantation mechanism 8 is ensured. Therefore, the occurrence of a phenomenon called "shikuri" can be suppressed, and seedlings can be planted in an appropriate planting posture.

Further, when the row stop clutch 102 is placed in the power cutoff state, the anti-phase torque Tan is not generated, and there is no possibility that unnecessary torque will be propagated around the transplantation mechanism 8. Moreover, a row stop clutch 102 for connecting and disconnecting power transmission from the interplant transmission 26 to the transplanting mechanism 8 is provided in the front and rear longitudinal planting transmission case 31 of the seedling planting device 2, and the planting transmission case 31, the anti-phase torque generating member 130 is disposed downstream of the row stop clutch 102, so the anti-phase torque generating member 130 is located near the transplant mechanism 8, which is the source of load fluctuations. Therefore, the effect of canceling out the rotational torque T of the transplantation mechanism 8 with the antiphase torque Tan, that is, the effect of leveling out load fluctuations is high.

(9). Fourth to Ninth Examples of Antiphase Torque Generating Member Next, a fourth example of the antiphase torque generating member 130 will be described with reference to FIGS. 21 and 22. In the fourth embodiment, the anti-phase torque generating member 130 is applied to a structure that transmits the rotation of the planting drive shaft 32 to the planting center shaft 91 using the chain 163. In this case, the driving sprocket 161 is rotatably supported on the planting drive shaft 32 in the planting transmission case 31, and the driven sprocket 162 is rotatably supported on the planting center shaft 91. Within the planting transmission case 31, a chain 163 for power transmission is wound around a main drive sprocket 161 and a driven sprocket 162. A torque limiter 164 is fitted onto the planting drive shaft 32 in a slidable but non-rotatable manner. When a load of more than a predetermined value is applied to the planting drive shaft 32, the torque limiter 164 is disengaged and power transmission from the planting drive shaft 32 to the main sprocket 161 is cut off. A row stop clutch 102 that connects and disconnects power transmission from the driven sprocket 162 to the planting center shaft 91 is fitted onto the planting center shaft 91 in a slidable and relatively non-rotatable manner. As shown in FIG. 22, the driving sprocket 161 and the driven sprocket 162 are configured as inconstant velocity sprockets having an elliptical shape or the like (non-circular). An idle roller 163' is brought into contact with the chain 163. With such a configuration, inconstant rotation is imparted to the planting central axis 91. In the fourth embodiment, the reduction ratio in the chain 163 transmission is 1/2 on average.

A power take-off shaft 165 extending parallel to the planting center axis 91 is rotatably supported further toward the rear end side of the planting center axis 91 within the planting transmission case 31 . One end side (right end side in the embodiment) of the power take-off shaft 165 is made to protrude outward from the planting transmission case 31 to the left and right. A leveling driving sprocket 166 is fixed to the opposite side of the row stop clutch 102 across the driven sprocket 162 in the planting center shaft 91, while a leveling driven sprocket 167 is fixed to the power take-off shaft 165. ing. A power transmission chain 168 is wound around the leveling main sprocket 166 and the leveling driven sprocket 167. It is configured so that the rotational power of the planting center shaft 91 is branched and transmitted to the power extraction shaft 165 via sprocket and chain transmission systems 166 to 168. When an optional device such as a chemical sprayer is attached to the seedling planting device 2, the rotational power of the power output shaft 165 is transmitted to the optional device.

The other end of the power take-off shaft 165 is bent into a crank shape. A tension spring 169 is mounted on the crank tip side of the power take-off shaft 165 and the inner circumferential wall of the planting transmission case 31 as a means for generating opposite phase torque. The tension spring 169 constantly biases the crank tip side of the power take-off shaft 165 to move it below the center of rotation of the power take-off shaft 165. The rotation of the power take-off shaft 165 via the leveling driven sprocket 167 causes the tension spring 169 to expand and contract. In the fourth embodiment, the power take-off shaft 165, the leveling driving and driven sprockets 166, 167, the chain 168, and the tension spring 169 constitute the antiphase torque generating member 130. That is, the power take-off shaft 165 is one of the components of the anti-phase torque generating member 130. In the fourth embodiment as well, there is an opposite phase torque generating member 130 for each combination of a total of four planted transmission cases 31 and row stop clutches 102. Even when configured as described above, the same effects as in the second and third embodiments are achieved.

In all of the fifth embodiment shown in FIG. 23 and the subsequent embodiments, similarly to the fourth embodiment, the rotation of the planting drive shaft 32 is transmitted to the planting central shaft 91 by the chain 163, and an antiphase torque generating member is added. 130 is applied. In the fifth embodiment, both the driving sprocket 161 provided on the planting drive shaft 32 and the driven sprocket 162 provided on the idle shaft 170 are circular but eccentric sprockets with inconstant velocity. A main drive gear 171 is fixed to an idle shaft 170, and a driven gear 172 is fixed to a planting center shaft 91. By meshing the main gear 171 and the driven gear 172, non-uniform rotation is applied to the planting center shaft 91. The average reduction ratio in the chain 163 transmission is 1, but the reduction ratio in the gear transmission from the main gear 171 to the driven gear 172 is 1/2. An idle roller 163' is brought into contact with the chain 163. It is also possible to have a configuration in which only one of the sprockets 161 and 162 is eccentric and the other is not eccentric.

The sixth embodiment shown in FIG. 24 and the seventh embodiment shown in FIG. 25 are modifications of the fourth embodiment shown in FIGS. 21 and 22. In the sixth embodiment shown in FIG. 24, a driving sprocket 161 provided on the planting drive shaft 32 is configured as a circular constant velocity sprocket. In the seventh embodiment shown in FIG. 25, the driving sprocket 161 provided on the planting drive shaft 32 is configured as a circular but eccentric sprocket with inconstant velocity. In the sixth and seventh embodiments, the reduction ratio in the chain 163 transmission is 1/2 on average.

In the eighth embodiment shown in FIG. 26, the driving sprocket 161 provided on the planting drive shaft 32 is configured as a circular but eccentric non-uniform sprocket, and the driven sprocket 162 provided on the planting central shaft 91 is configured as a circular constant speed sprocket. It's a sprocket. In this case, the reduction ratio in the chain 163 transmission is also 1/2 on average.

In the ninth embodiment shown in FIG. 27, the driving sprocket 161 provided on the planting drive shaft 32 is configured as an elliptical (non-circular) inconstant velocity sprocket, and the driven sprocket 162 provided on the planting center axis 91 is configured as an elliptical (non-circular) sprocket. , it is configured as a polygonal (non-circular) inconstant velocity sprocket. In this case, the reduction ratio in the chain 163 transmission is also 1/2 on average. Since the driven sprocket 162 is formed into a substantially rectangular shape, acceleration and deceleration occur four times in one rotation of the planting center shaft 91.

As is clear from the above embodiment and FIGS. 21 to 27, the transmission case 11 that changes the speed of the power of the engine 10 mounted on the traveling aircraft 1, and the transplant with the planting claw 96 that draws a non-circular motion trajectory a seedling planting device 2 having a mechanism 8; an inter-plant transmission device 26 that changes the operating speed of the transplanting mechanism 8 relative to the traveling speed of the traveling body 1 to change the spacing between plants; In the rice transplanter equipped with inconstant velocity members 161 and 162 that transmit the It further includes an anti-phase torque generating member 130 that applies a phase torque Tan, and is capable of transmitting power to the front and rear longitudinal planting transmission case 31 of the seedling planting device 2 to an optional device attached to the seedling planting device 2. Since a power take-off shaft 165 is provided and the power take-off shaft 165 is a component of the anti-phase torque generating member 130, load fluctuations (torque fluctuations) acting on the transplant mechanism 8 are leveled out and While ensuring smooth rotation, the power take-off shaft 165 can also be used as the anti-phase torque generating member 130, simplifying and reducing the weight of the power transmission structure to the seedling planting device 2. can contribute to

(10). Others The present invention can be embodied in various ways other than the embodiments described above. For example, the inter-stock transmission 26 can be built into the mission case 11, and in this case, one upstream inconstant velocity member is built into the mission case 11. When providing inconstant velocity members in each of the traveling body 1 and the seedling planting device 2, the acceleration/deceleration ratio (inconstant velocity ratio) may be set as necessary. Therefore, depending on the case, it is also possible to make the acceleration/deceleration ratio (inconstant velocity ratio) on the traveling machine body 1 side smaller than the inconstant velocity conversion ratio in the seedling planting device 2. Belt transmission (preferably a timing belt) may be used instead of chain transmission. In any of the first to ninth embodiments, it is possible to arrange the crank structure and tension spring of the antiphase torque generating member 130 outside the planting transmission case 31.

1 Traveling body 2 Seedling planting device 8 Transplanting mechanism 10 Engine 11 Mission case 26 Interplant transmission 36 Rotary case 37 Planting claw member 40 Interplant case 87 Planting transmission shaft 91 Planting central axis 96 Planting claw 98 Downstream inconstant speed Main drive bevel gear 99 Downstream inconstant speed driven bevel gear 102 Row stop clutch 105 Operation ring 130 Opposite phase torque generating member 131 End case 132 Planting branch shaft 133 Leveling bevel gear 134 Eccentric shaft 136 Tension spring 142 External teeth 143 Leveling flat Gears 145, 155 Locking pins 146, 156, 169 Tension spring 152 First flat gear for leveling 153 Second flat gear for leveling 161 Main drive sprocket 162 Driven sprocket 163, 168 Chain 164 Torque limiter 165 Power take-off shaft 166 Leveling Driven sprocket 167 Driven sprocket 169 for leveling Tension spring

Claims (4)

a seedling planting device supported by a running section;
an interplant transmission device that transmits power to the seedling planting device and can change the working speed of the seedling planting device with respect to the traveling speed of the traveling section,
The interplant transmission device includes an output shaft that transmits power to the seedling planting device, a plurality of transmission gears supported in parallel on the output shaft, and a counter shaft provided in parallel to the output shaft. a plurality of counter gears supported by the counter shaft and corresponding to each of the plurality of transmission gears;
The power transmission path to the output shaft can be switched to a plurality of paths by selecting one transmission gear from the plurality of transmission gears,
The plurality of transmission gears include a plurality of outer transmission gears located on an end side in the axial direction of the output shaft, and an inner transmission gear located between the plurality of outer transmission gears,
The rice transplanter, wherein both of the outer transmission gears are configured to transmit a slower power to the seedling planting device than the inner transmission gear. The rice transplanter according to claim 1, wherein at least one of the plurality of outer transmission gears is an inconstant speed gear. The rice transplanter according to claim 1 or 2, wherein a plurality of said inner transmission gears are provided. The rice transplanter according to claim 3, wherein the inner transmission gear includes a constant velocity gear.

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