JP3408880B2 - Transmission structure of rice transplanter - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle equipped with a plurality of planting mechanisms and diverging power of an engine provided in a traveling body via a plurality of transmission mechanisms. A transmission system is configured to transmit to each of the planting mechanisms.In a power transmission system in each of the transmission mechanisms, in a state where a driving load is lower than a set load,
When the driven-side transmission and the driving-side transmission rotate integrally, and the driving load exceeds a set value, one of the driven-side transmission and the driving-side transmission is in a position fixed state. An overload prevention clutch for preventing overload is provided by allowing retreating movement in the direction of the rotation axis relative to the other side and preventing overload, and power from the traveling machine body is transmitted to each of the transmission mechanisms. In each of the plurality of transmission branch portions that are branched in such a manner that the rotating body on the driving side and the rotating body on the driven side are switched to a transmission state in which they rotate integrally and a power cutoff state in which they are separated, The present invention relates to a rice transplanter provided with a thread number changing clutch in which any of the rotating bodies can be moved and operated by an operating tool. 2. Description of the Related Art In a rice transplanter having the above structure, conventionally,
The overload prevention clutch has a configuration in which the power of the engine is provided on the power transmission side of the power transmission branch where the power of the engine is branched to each power transmission mechanism, and the total load obtained by adding the loads of the plurality of planting mechanisms is added. When the driving load, which is the load, exceeds the set load, each power transmission element rotates relatively, and the disadvantage that power transmission is continued in an overload state can be avoided. [0003] Such a configuration is, for example, when power such as a weed or the like is wound around the planting mechanism or the driving load becomes excessive due to contact with a stone or the like, and power transmission is performed. It is possible to prevent such inconveniences as being continued and causing the engine to stop due to an overload applied to the engine, or being damaged by applying excessive force to the planting mechanism. . [0004] However, in the above-described conventional configuration, a set load for preventing overload is provided for a driving load obtained by adding all loads of a plurality of planting mechanisms. The set load is much larger than the individual load of each planting mechanism. As a result, if the set load is set slightly higher, overload is applied to any one of the plurality of planting mechanisms,
In the case where a normal rated load is applied to other planting mechanisms, an excessive driving force acts on the planting mechanism in an overloaded state, and the planting mechanism may be damaged. Get higher. Also, if the set load is set low,
For example, at the time of starting, for example, simultaneously activating all the planting mechanisms, a driving load larger than the driving load in the normal operating state may be applied.In such a case, the overload prevention clutch operates, There is a disadvantage in that the planting operation cannot be performed, and it has been difficult to set the set load to a value at which the overload prevention clutch is always operated in an appropriate state. Therefore, as a method of solving the above-mentioned problem, a drive shaft provided for directly driving the planting mechanism in a plurality of transmission mechanisms for each planting mechanism includes:
Although a configuration in which the overload prevention clutch is provided separately is conceivable, in such an improved configuration, it is necessary to newly provide a plurality of members for configuring the overload prevention clutch for each drive shaft, There was a drawback that the number of parts increased and the structure became complicated. The present invention has been made in view of such a point, and an object of the present invention is to reduce the set load for operating the overload prevention clutch by using a rational configuration as much as possible without complicating the structure. It is an object of the present invention to provide a transmission structure of a rice transplanter that can be appropriately adapted to the load of a planting mechanism. A feature of the present invention is that a plurality of planting mechanisms are provided, and the power of an engine provided on the traveling body is branched via a plurality of transmission mechanisms. A transmission system is configured to transmit to the planting mechanism, and in a power transmission system in each of the transmission mechanisms, when the driving load is lower than the set load, the driven transmission unit and the driving transmission unit integrally rotate. When the driving load exceeds the set load, one of the driven-side transmission and the driving-side transmission is
An overload prevention clutch that allows retreating movement in the direction of the rotation axis and relative rotation with respect to the counterpart in the position fixed state to prevent overload is provided, and that the power from the traveling machine body is At each of the plurality of transmission branch portions branched to the transmission mechanism, the drive-side rotator and the driven-side rotator are switched into a transmission state in which they integrally rotate and a power cutoff state in which they are separated. Instead, in a rice transplanter provided with a number-of-steps changing clutch in which one of the rotating bodies is movably operated by an operating tool, the overload prevention clutch is separately provided for each of the transmission branch portions. , In the overload prevention clutch,
Multiple balls for torque transmission
A plurality of engagement recesses that engage and engage are spaced along the circumferential direction.
When the driving load exceeds a set load,
One of the transmissions rides on the ball and makes relative rotation
To allow for the number of clutches
The driven-side rotating body is made into a single member with the position-fixed-side transmission body.
And a single rotation phase.
Only when the power is switched off.
The recesses permitting the moving operation of the operating tool are inserted into each of the engagement recesses.
Radially outer end positions of each engagement recess at different positions in the circumferential direction
The point is that it is formed in such a state as to enter the inner side in the radial direction . According to the characteristic structure of the present invention , in each of the plurality of branch transmission portions where the power from the traveling machine body branches to each transmission mechanism, the power corresponds to each planting mechanism. Since the overload prevention clutch is provided separately for each, the set load for overload prevention can be set to an appropriate value as an overload state with respect to the normal load of the planting mechanism. Therefore, it is possible to avoid the inconvenience that the power transmission is continued until the load becomes excessively large as the planting mechanism is broken, and the load on the engine does not exceed the total value of the set loads. Can also be avoided. In addition, in each of the plurality of branch transmission portions, only one of the plurality of planting mechanisms is stopped to change the number of planting lines provided for changing the number of planting lines. Utilizing the configuration, the non-operating-side rotating body of each rotating body for constituting the clutch in the number-of-steps changing clutch, that is, the rotating body in a fixed position state, and each transmission body in each overload prevention clutch. Since the transmission body on the fixed position side is integrally formed by a single member, the number of parts can be reduced as compared with a case where all members are newly provided with an overload prevention clutch. Further , in each overload prevention clutch, when a torque transmitting ball is engaged in an engagement concave portion formed at a position facing each other of each transmission body, power transmission is performed, and when an overload state occurs, any of the overload prevention clutches is transmitted. The transmitting body rides on the ball and relative rotation is allowed. The number-of-rows changing clutch is provided with a concave portion on the driven side that allows the clutch disengagement operation of the operating tool only in the predetermined rotational phase so that the clutch is in the clutch disengaged state only in the predetermined rotational phase. The posture is configured to be stopped in a state of being separated from the field, but the concave portion is located at a position different in the circumferential direction with respect to each of the engaging concave portions into which the power transmission balls are engaged, and By being formed in a state of entering the radially inward side from the radially outer end position, the engaging concave portion and the concave portion are compared with the case where the positions are provided differently in the rotational axis center direction or the radial direction. In addition, the transmission body in the overload prevention clutch can be reduced in size in the axial direction with a small diameter. According to the characteristic structure of the present invention , when an overload is applied to each planting mechanism, the overload prevention clutch is always operated to keep the overload applied. Inconveniences such as breakage of the planting mechanism due to continued power transmission can be avoided, and overload on the engine can be effectively prevented. In addition, with a rational configuration, a plurality of overload prevention clutches are connected to all members. Can be completed with a simple structure as compared with the case where a new device is provided. Furthermore, the structure of the overload prevention clutch, and a structure for cutting operation only Article number change clutch at a predetermined rotation phase, by rationally configuration, fit the overload prevention clutch compact shape It became possible. Embodiments will be described below with reference to the drawings. FIG.
As shown in FIG. 1, there is shown a riding type rice transplanter in which a seedling planting device 3 is connected to a rear portion of a traveling machine body 1 via a parallel quadruple link mechanism 2 so as to be able to move up and down. The traveling body 1 has an engine 4 mounted on a front portion thereof, and the motive power of the engine 4 is transmitted to front and rear wheels 6 and 7 via a transmission 5 so as to be driven for traveling. A power transmission system is configured so that the power from the engine 4 and the power after being shifted by the transmission 5 are transmitted to the seedling planting device 3 via the power take-out shaft 8. A transmission system for planting work is configured. The seedling planting device 3 comprises a feed case 10 into which power from the machine body is input to each pipe-shaped main frame 9 disposed along the lateral direction of the machine body, and a plurality of planting transmission cases. 11 are fixedly connected to each other to form a frame portion, and a plurality of seedling rests 12 which reciprocate and move laterally with the seedlings placed thereon, a plurality of seedlings taken out from the lower end of the seedling rest 12 and planted in a field. A planting mechanism 13 and a ground float 14 for leveling are provided. Each planting mechanism 13
Is provided at the rear part of the planting transmission case 11 with a rotating case 15 which is driven to rotate around the horizontal axis, and at both ends of the rotating case 15, the planting claw support case 16 is rotatable relative to the horizontal axis. While pivotally supported, the tip of the planting claw 17 attached to the planting claw support case 16 with the rotation of the rotating case 15 draws a substantially elliptical seedling removal trajectory in a side view. As described above, a relative rotation mechanism (not shown) for relatively rotating the planting claw support case 16 is provided. As shown in FIG.
0 is connected and fixed to the main frame 9 at a substantially central portion in the lateral width direction of the fuselage, and the planting transmission case 11 has three portions at both sides in the lateral width direction of the fuselage and at each central portion in the lateral width direction.
They are connected and fixed in a state of being juxtaposed. A pair of planting mechanisms 13 are disposed on both left and right sides of each planting transmission case 11 in a state of being driven to rotate around the same axis. Therefore, in this embodiment, the configuration is such that the six-row planting operation is performed by each planting mechanism 13 as the vehicle travels. Next, the transmission structure will be described. As shown in FIG. 4, the power from the traveling machine body 1 is transmitted to the lateral transmission shaft 18 via the power take-out shaft 8 and the feed case 10, and from the lateral transmission shaft 18, the planted transmission case 11 Power is transmitted in a state of being branched to each transmission chain 19 as a transmission mechanism provided inside. The three transmission branch portions 20 from the lateral transmission shaft 18 to the respective transmission chains 19 are provided with a number-change clutch 21 which can intermittently operate the power.
When the driving load of the planting mechanism 13 exceeds the set load, the overload prevention clutch 22 for allowing the driven-side transmission and the driving-side transmission to rotate relative to each other to prevent overload is provided. Separately interposed. That is, as shown in FIG. 1, in the transmission branching portion 20 inside the planting transmission case 11 on the front side of the fuselage, the horizontal transmission shaft 18 is rotatable integrally and slidably in the axial direction. The driving-side rotator 23 of the changing clutch 21 is fitted outside the spline, and the driven-side rotator 24 of the thread number changing clutch 21 is mounted on the driving side Rotating body 23
In a state where the movement to the side is prevented, the free end is freely fitted to the lateral transmission shaft 18, and the drive side rotating body 23 is configured to be urged toward the driven side rotating body 24 by the coil spring 25, An engaging portion 26 is formed so as to rotate integrally with the opposing portions of the rotating bodies 23 and 24 in an engaging state.
Then, a shift fork 27 as an operating tool that is rotatable around the vertical axis P is rotated to oppose the biasing force of the coil spring 25, and the shift fork 27 at the bite portion 26 of the rotating bodies 23 and 24 is rotated. By releasing the occlusion, each rotating body 23, 24
Are separated so as to be in a power cutoff state. Therefore, the number-of-steps changing clutch 21 is
In the non-operation state of 7, the power transmission state is maintained, and when the shift fork 27 is rotated by an external operation force, the state is switched to the power cutoff state. As shown in FIG. 2, the shift fork 2
A support shaft 29 that is inserted and fitted into an oval insertion hole 28 formed on the base end side of the base 7 is rotatably supported while penetrating the planting transmission case 11 in the vertical direction. After the shift fork 27 is pre-installed together with the members mounted on the lateral transmission shaft 18, the shift fork 27 can be inserted from the outside of the planting transmission case 11 to perform the installation. The support shaft 29 is supported by a retaining member 30 at a tip end in the insertion direction that protrudes outward from the planting transmission case 11, and is supported by a planting member on the opposite side of the retaining portion. A rotation operation arm 31 for rotating the shift fork 27 is provided outside the transmission case 11 so as to be integrally rotatable. Next, the configuration of the overload prevention clutch 22 will be described. A non-operating-side rotator of the thread number changing clutch 21, that is, a driven-side rotator 24 and a drive-side transmission 32 formed integrally with a single member are fitted to the lateral transmission shaft 18 at their free ends. The drive side transmission 3
2, the driven-side transmission body 33 adjacent to the rotation axis center side laterally,
The free end is provided on the lateral transmission shaft 18 so as to be fitted outside.
Engaging recesses 35 into which a plurality of torque transmitting balls 34 enter and engage are formed at opposing locations of the transmission elements 32 and 33 at appropriate intervals in the circumferential direction. The driven-side transmission body 33 is configured to be pressed and urged toward the drive-side transmission body 32 by a coil spring 38 supported on both sides by spring receiving members 36 and 37. Each transmission 32, 3
Numeral 3 rotates integrally with each ball 34 depending on the engagement state. The driven sprocket 33 is integrally formed with a driving sprocket 39 for the transmission chain 19, and the power is transmitted to the planting mechanism 13 in the integrally rotated state.
Will be transmitted to On the planting mechanism 13 side, for example, when the planting claw 17 comes into contact with a stone or the like and the driving load (driving torque) exceeds the set load (set torque), the ball 34 and the ball 34 are brought into an abnormal state. At the engagement portion, the torque that can be transmitted is exceeded, and the driven-side rotating body 33 moves in the direction away from the driving-side rotating body 32 against the spring biasing force of the coil spring 38, and 32 is the ball 34
, And the relative rotation of the rotating bodies 332 and 33 is allowed. Therefore, in such an overload state, the rotational power is not transmitted to the planting mechanism 13 side, and the planting mechanism 1
An excessive force is not applied to 3 and the risk of damaging the planting claws 17 can be avoided. In the above overload state, the sprocket 3
9 also moves sideways, but the transmission chain 1
9 is configured to be wound and stretched over a sufficiently long distance with respect to the diameter of the sprocket 39, so that problems such as the transmission chain 19 coming off from the sprocket 39 do not occur. As shown in FIG. 3, a ball 3 for torque transmission is provided on an outer peripheral portion of the driven side transmission 33.
In a state in which each of the engagement recesses 35 engages with the engagement recesses 35 in the circumferential direction at a different position in the circumferential direction with respect to each of the engagement recesses 35, and enters a radially inward side from the radial outer end position of each engagement recess 35, Only the recess 40 is formed. And the shift fork 2
7 is integrally formed with an operation restricting portion 27a that comes into contact with the outer peripheral portion of the driven-side transmission body 33. When the shift fork 27 is in the clutch engaged position (non-operating state), the operation restricting portion 27a is formed. Reference numeral 27a is provided so as to be substantially in contact with the arc-shaped outer peripheral portion 33a of the driven-side transmission body 33.
, The operation restricting portion 27a must enter the recess 40. Therefore, only when the rotation case 15 of the planting mechanism 13 is in the predetermined rotation phase, the line number changing clutch 21 can be turned off. This predetermined rotation phase is determined by a pair of planting claws 17 attached to the rotation case 15.
Are set so as to be in substantially the same horizontal position, and the planting claw 17 in the drive stopped state is set as far as possible upward from the field scene. With this configuration, as is apparent from FIG. 3, the diameter of the driven-side transmission body 33 needs to be sufficient to form the engagement recess 35 with which the torque transmitting ball 34 is engaged. The size can be minimized, the diameter can be smaller than the configuration in which the concave portion 40 is formed on the radially outward side of the engagement concave portion 35, and the engagement concave portion 35 can be reduced. As compared with the case where the concave portion 40 is formed by shifting the position in the direction of the rotation axis, the thickness in the direction of the rotation axis can be reduced. (2) In the above-described embodiment, the case where the overload prevention clutch 22 is provided on the lower side of the transmission of the number-of-row changing clutch 21 is illustrated. It is good also as a structure provided in a good side. In the claims, reference numerals are provided to facilitate comparison with the drawings, but the present invention is not limited to the configuration shown in the attached drawings.

[Brief description of the drawings] FIG. 1 is a cross-sectional plan view of a transmission branch. FIG. 2 is a longitudinal sectional view of a support portion of the shift fork. FIG. 3 is a side view of a driven-side rotating body. FIG. 4 is a plan view showing a branch transmission configuration. FIG. 5 is an overall side view of the rice transplanter. [Explanation of symbols] 13 Planting mechanism 21 number change clutch 22 Overload prevention clutch 23, 24 rotating body 27 Operating tools 32,33 transmission 34 ball 35 Engagement recess 40 recess

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) A01C 11/02

Claims (1)

(57) [Claim 1] A plurality of planting mechanisms (13) are provided, and the power of an engine (4) provided in a traveling body (1) is transmitted through a plurality of transmission mechanisms (19). A transmission system is configured to transmit to each of the planting mechanisms (13) in a state where the driving load is lower than a set load in a power transmission system of each of the transmission mechanisms (19). Transmission (3
3) and the transmission-side transmission element (32) rotate integrally, and when the driving load exceeds a set load, the transmission-side transmission element (33).
One of the transmission and the transmission-side transmission element (32) is allowed to retreat and rotate relative to the counterpart in the position-fixed state in the direction of the axis of rotation, thereby preventing overloading. A load prevention clutch (22) is provided, and the power from the traveling body (1) side is used for the transmission mechanisms (1).
In each of the plurality of transmission branch portions (20) branched to 9), the driving-side rotating body (23) and the driven-side rotating body (24) are connected to each other in a transmission state in which they rotate integrally. In order to switch to a power cut-off state in which the rotating members (23) are separated from each other, a row number changing clutch (21) is provided, which is configured so that any one of the rotating bodies (23) and (24) can be moved and operated by an operating tool (27). A rice transplanter, wherein the overload prevention clutch (22) is separately provided in each of the transmission branch portions (20), and the transmission elements (32), () in the overload prevention clutch (22) are provided. 33), a plurality of engagement recesses (35) in which a plurality of torque transmitting balls (34) enter and engage with each other are formed at intervals along the circumferential direction at positions facing each other, and the driving load is set. If the load is exceeded, one of the transmissions (3 ) Rides on the ball (34) to allow relative rotation, and the driven-side rotator (24) in the number-of-steps changing clutch (21) is simply combined with the position-fixed-side transmission (32). It is configured to be integrally formed by one member, and the other power transmission body (33) allows the operation of the operation tool (27) to be switched to the power cutoff state only in a predetermined rotation phase. The engaging recess (40) is inserted into each of the engaging recesses (3).
5) A transmission structure of a rice transplanter, which is formed at a position different in the circumferential direction from that of the engagement concave portion (35) so as to enter the radially inner side from the radially outer end position.