JP2012231760A - Rice transplanter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rice transplanter having a compact hydraulic system.SOLUTION: The rice transplanter 1 includes a pump 63 for an actuator to be a hydraulic pump driven by the power of an engine 14, a transmission case 18 filled with a hydraulic fluid to be supplied to the pump 63 for the actuator, a lift cylinder 35 which is arranged behind the transmission case 18 and to which pressurized oil is fed from the pump 63 for the actuator to lift up and down a planting part 40, and a lift valve unit 65 having a control valve 65f inside which controls the flow of hydraulic fluid to the lift cylinder 35, wherein the lift valve unit 65 is installed in a rear part of the transmission case 18.

Description

  The present invention relates to a rice transplanter.

  In the conventional rice transplanter, a hydraulic pump is driven by engine power, a lifting cylinder is operated by hydraulic oil pumped from the hydraulic pump, and the hydraulic oil flowing in the lifting cylinder is built into the lifting valve unit. It is comprised so that a planting part may be raised / lowered by controlling by (for example, refer patent document 1).

  The rice transplanter shown in Patent Document 1 is configured such that a lifting cylinder is provided on a connecting frame that connects a transmission case and a rear axle case, and a lifting valve unit is attached to the front axle case. According to the rice transplanter, the hydraulic piping connecting the lifting valve unit and the lifting cylinder and the hydraulic piping connecting the lifting valve unit and the transmission case become long, and the hydraulic system is not compact.

JP 2003-79211 A

  The purpose is to provide a rice transplanter with a compact hydraulic system.

  The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described.

  In claim 1, a hydraulic pump driven by engine power, a transmission case filled with hydraulic oil supplied to the hydraulic pump, and disposed behind the transmission case, the pressure oil is supplied from the hydraulic pump. In a rice transplanter comprising an elevating cylinder that elevates and lowers a planting part by being fed oil, and an elevating valve unit that includes a control valve that controls the flow of pressure oil to the elevating cylinder, the elevating valve unit includes: It is attached to the rear part of the mission case.

  According to a second aspect of the present invention, the elevating valve unit is formed with a communication hole for returning the hydraulic oil on a contact surface that contacts the transmission case.

  According to a third aspect of the present invention, the elevating valve unit is disposed below the step.

  According to a fourth aspect of the present invention, an HST for shifting the power of the engine is provided, and the HST is disposed in a front portion of the mission case.

  According to a fifth aspect of the present invention, an oil cooler for cooling the HST is disposed on a side portion of the radiator.

  As effects of the present invention, the following effects can be obtained.

  According to the first aspect, the length of the hydraulic piping connecting the lifting valve unit and the transmission case and the hydraulic piping connecting the lifting valve unit and the lifting cylinder can be shortened, and the hydraulic system becomes compact.

  According to the second aspect of the present invention, piping for connecting the elevating valve unit and the transmission case becomes unnecessary, and the hydraulic system becomes more compact.

  According to the third aspect of the present invention, the lift valve unit can be easily maintained by removing the step or opening a part of the step.

  According to the fourth aspect of the present invention, the elevating valve unit is separated from the HST serving as the heat source, and the temperature rise of the hydraulic oil flowing through the elevating valve unit can be suppressed. Accordingly, the amount of hydraulic oil can be reduced, the hydraulic oil can be deteriorated, and the number of hydraulic oil replacements can be reduced.

  In Claim 5, the cooling efficiency of HST can be improved.

1 is an overall side view of a rice transplanter 1 according to an embodiment of the present invention. The perspective view which shows the structure of the mission case 18 and the raising / lowering valve unit 65 of the rice transplanter 1 which concerns on one Embodiment of this invention. The side view which shows the structure of the mission case 18 and the raising / lowering valve unit 65 of the rice transplanter 1 which concerns on one Embodiment of this invention. The perspective view which shows the structure of the mission case 18 front part of the rice transplanter 1 which concerns on one Embodiment of this invention. The perspective view which shows the other structure of the mission case 18 front part of the rice transplanter 1 which concerns on one Embodiment of this invention. The perspective view which shows the other structure of the mission case 18 front part of the rice transplanter 1 which concerns on one Embodiment of this invention. The perspective view which shows the structure of the mission case 18 rear part of the rice transplanter 1 which concerns on one Embodiment of this invention. The perspective view which shows the structure of the mission case 18 and the raising / lowering valve unit 65 of the rice transplanter 1 which concerns on one Embodiment of this invention. The front view of the raising / lowering valve unit 65 of the rice transplanter 1 which concerns on one Embodiment of this invention. The rear view of the mission case 18 of the rice transplanter 1 which concerns on one Embodiment of this invention. The figure which shows the structure of the hydraulic circuit 70 of the rice transplanter 1 which concerns on one Embodiment of this invention. The figure which shows the structure which controls the traveling speed of the rice transplanter 1 which concerns on one Embodiment of this invention. The perspective view which shows the structure of the motor case 100 of the rice transplanter 1 which concerns on one Embodiment of this invention. The partial sectional view of motor case 100 of rice transplanter 1 concerning one embodiment of the present invention. (A) When the transmission motor 91 is operable. (B) When the speed change motor 91 cannot be operated. The left view of the left case 100L of the rice transplanter 1 which concerns on one Embodiment of this invention.

  Below, the whole structure of the rice transplanter 1 which concerns on one Embodiment of this invention is demonstrated using FIG. In the present embodiment, the rice transplanter is an eight-row planter, but this is not particularly limited, and a six-plant or ten-row planter may be used.

  The rice transplanter 1 includes a traveling unit 10 and a planting unit 40, and is configured so that seedlings can be planted in a field by the planting unit 40 while traveling by the traveling unit 10. The planting unit 40 is disposed behind the traveling unit 10 and is connected to the rear portion of the traveling unit 10 via the lifting mechanism 30.

  In the traveling unit 10, the front axle case 16 is supported by the front portion of the vehicle body frame 11, and the front wheels 12 are attached to the left and right sides of the front axle case 16. A rear axle case 17 is supported on the rear portion of the vehicle body frame 11, and the rear wheels 13 are attached to the left and right sides of the rear axle case 17.

  In the traveling unit 10, the engine 14 is provided in the front part of the vehicle body frame 11. A transmission case 18 is supported by the front portion of the vehicle body frame 11 and is disposed behind the engine 14. The transmission case 18 and the rear axle case 17 are connected by a connecting frame 15.

  In the traveling unit 10, a driving operation unit 20 is provided in the middle part of the vehicle body frame 11 before and after. A dashboard 21 is disposed at the front of the driving operation unit 20, a steering handle 24 is disposed at the center of the left and right of the dashboard 21, and a driver seat 22 is disposed behind the steering handle 24. A step 23 for getting on and off and for replenishing seedlings is arranged around the driver's seat 22. In the driving operation unit 20, a plurality of operation tools including the main transmission lever 25 and the shift pedal 26 are arranged, and it is possible to perform appropriate operations on the traveling unit 10 and the planting unit 40 with these operation tools. It is said.

  In the planting part 40, the planting mission case 47 is supported near the center of the lower part of the planting frame 49, and the transmission shaft extends from the planting mission case 47 to the left and right sides. The four planting transmission cases 46 are respectively extended rearward from the transmission shaft, and are arranged at appropriate intervals in the left-right direction.

  A rotary case 44 is rotatably supported on the left and right sides of the rear end portion of each planting transmission case 46. The number of the rotary cases 44 is the same as the number of planting strips, that is, eight in this embodiment. Then, the two planting claws 45 are attached to both sides of the rotary case 44 in the longitudinal direction so as to sandwich the rotation fulcrum of the rotary case 44.

  The seedling table 41 is arranged above the planting transmission case 46 in a tilted state with a front height and a low height. The seedling table 41 is attached to the rear portion of the planting frame 49 so as to be reciprocally movable in the left-right direction via a guide rail. The seedling table 41 can be reciprocated horizontally by a lateral feed mechanism.

  The seedling mounting bases 41 having a plurality of (eight) seedling mat mounting portions are arranged in the left-right direction so that each lower end side faces one rotary case 44. Then, the seedling mat is placed on each seedling stage 41, and one seedling can be cut from the seedling mat on the seedling stage 41 by the planting claws 45 when the rotary case 44 rotates.

  In the planting part 40, a plurality of floats 42 are supported by a planting frame 49 so that the float 42 can move up and down and the leveling rotor 43 can move up and down. Moreover, the drawing marker 48 is rotatably supported on the left and right sides of the planting frame 49.

  The elevating mechanism 30 is a mechanism for elevating the planting unit 40, and includes an elevating link mechanism 34 having a top link 31, a lower link 32 and a support link 33, an elevating cylinder 35, and the like. The front part of the top link 31 is connected to the upper part of the link support member 19 standing from the rear axle case 17, and the front part of the lower link 32 is connected to the lower part of the link support member 19. The rear part of the top link 31 is connected to the upper part of the support link 33, and the rear part of the lower link 32 is connected to the lower part of the support link 33. The planting part 40 is attached to the rear part of the support link 33 via a hitch bracket.

  A mast 36 is erected from the front end of the lower link 32, and an upper portion of the mast 36 is connected to a piston rod 35 a protruding from the elevating cylinder 35. A reinforcing member 37 is connected between the upper portion of the mast 36 and the rear end of the lower link 32. The raising / lowering mechanism 30 extends / lowers the planting part 40 by extending / contracting the raising / lowering cylinder 35 and driving the raising / lowering link mechanism 34 to an up-down direction.

  Hereinafter, the structure in the vicinity of the mission case 18 will be described with reference to FIGS.

  The mission case 18 houses a part of the power transmission mechanism from the engine 14 to the front wheels 12 and the rear wheels 13 and the planting part 40. Further, the inside of the transmission case 18 is filled with hydraulic oil flowing through the hydraulic circuit 70 shown in FIG. 11, and serves as a hydraulic oil tank that returns the hydraulic oil. The hydraulic circuit 70 is a hydraulic system of the rice transplanter 1 according to an embodiment of the present invention.

  As shown in FIG. 2, left and right front axle cases 16 are provided at the front and rear central portions of the mission case 18 and at the left and right lower portions. The front end of the cylindrical connecting frame 15 is fixed to the rear part of the transmission case 18 and at the center left and right, and the rear end of the connecting frame 15 is fixed to the front part of the rear axle case 17. The connection frame 15 is located in the left and right center of the rice transplanter 1. A bracket 15a is provided on the upper rear side of the connecting frame 15, and the lifting cylinder 35 is rotatably supported via the bracket 15a.

  The mission case 18 is provided with an HST 61, an HST pump 62, an actuator pump 63, a power steering case 64, and a lift valve unit 65.

  As shown in FIGS. 2, 3, and 4, the HST 61 shifts the power of the engine 14 in a stepless manner, and is disposed at the front upper part of the mission case 18 and on the upper left side. It is attached. As shown in FIG. 11, the HST 61 includes a hydraulic pump 61c and a hydraulic motor 61d. The HST 61 drives the hydraulic pump 61c with the power of the engine 14 to change the amount of pressure oil supplied from the hydraulic pump 61c. Thus, the motor shaft of the hydraulic motor 61d is rotated so as to be variable.

  Excess hydraulic oil and leak oil accumulated in the HST 61 are returned to the mission case 18 via the hydraulic pipe 74. Specifically, as shown in FIG. 4, a pipe connecting portion 61b is provided at the front portion of the HST 61, and one end of a hydraulic pipe 74 is connected to the pipe connecting portion 61b. The other end of the hydraulic pipe 74 is connected to a pipe connecting part 18 a provided on the right side surface of the front end of the transmission case 18, bypassing the front part of the power steering case 64. In this way, the hydraulic piping 74 is less likely to be exposed to mud or the like that is repelled from below, and the hydraulic oil is also easily cooled. The pipe connecting portion 18a is located below the oil level of the hydraulic oil filled in the mission case 18.

  Further, an oil cooler may be interposed in the middle of the hydraulic pipe 74. For example, as shown in FIG. 5, an oil cooler 84 is interposed in the middle of the hydraulic piping 74. The oil cooler 84 is formed by being appropriately curved a plurality of times so that the hydraulic piping has an area equivalent to the area of the vent opening opened in the radiator 82 in a side view, and is disposed on the side of the radiator 82. It is attached. Specifically, the radiator 82 is disposed on the right side of the radiator 82 so as to face a fan provided on the right side of the engine 14 for cooling the radiator 82 with the radiator 82 interposed therebetween. Thereby, since the oil cooler 84 is located on the ventilation path of the fan together with the radiator 82, the cooling efficiency of the hydraulic oil flowing through the hydraulic pipe 74 and the HST 61 can be improved.

  As shown in FIG. 6, the oil cooler 84 may be provided with a plurality of radiating fins 85. In this case, since the cooling area of the oil cooler 84 can be increased by the radiation fins 85, 85..., The cooling efficiency of the hydraulic oil flowing through the hydraulic pipe 74 can be further improved. The radiator 82 and the fan for cooling the radiator 82 are arranged on the left side of the engine 14 so that the hydraulic pipe 74 that connects the HST 61 and the oil cooler 84 can be shortened.

  That is, conventionally, in order to cool the hydraulic system of the HST 61 including the hydraulic pipe 74, the cooling fan 83 is disposed on the left side of the HST 61 as shown in FIG. 1, and the cooling fan 83 is attached to the input shaft of the HST 61. However, according to the oil cooler 84 shown in FIGS. 5 and 6, the cooling fan 83 is not required, so that the space between the left and right front axle cases 16 can be shortened and the front wheel 12 can be configured compactly.

  As shown in FIGS. 2 and 4, the HST pump 62 pumps hydraulic oil to the HST 61, is disposed at the front upper part of the mission case 18, at the upper right side, and is attached to the mission case 18. . As shown in FIG. 11, the HST pump 62 is driven by the power of the engine 14, sucks the hydraulic oil in the transmission case 18 from the hydraulic pipe 79, converts the hydraulic oil into pressure oil, and connects the hydraulic pipe 71 to the HST 61. The pressure is fed to the hydraulic pump 61c.

  The HST pump 62 is connected to the HST 61 via a hydraulic pipe 71. Specifically, as shown in FIG. 4, a pipe connecting part 62 a serving as a discharge port is provided at the rear part of the HST pump 62, and one end of the hydraulic pipe 71 is connected to the pipe connecting part 62 a. Bypasses the front part of the power steering case 64 on the front part of the transmission case 18 and the other end of the hydraulic pipe 71 is connected to a pipe connecting part 61 a provided at the front part of the HST 61. In this way, the hydraulic piping 71 is less likely to be splashed by mud and the like repelled from below, and the hydraulic oil is also easily cooled.

  As shown in FIGS. 2 and 4, the actuator pump 63 pumps hydraulic oil to various actuators. The actuator pump 63 is disposed on the right side of the HST pump 62 and is attached to the mission case 18 together with the HST pump 62. As shown in FIG. 11, the actuator pump 63 is driven by the power of the engine 14, sucks the hydraulic oil in the transmission case 18 from the hydraulic pipe 79, converts the hydraulic oil into pressure oil, and power steering from the hydraulic pipe 72. Pump to case 64.

  The actuator pump 63 is connected to the power steering case 64 via a hydraulic pipe 72. Specifically, as shown in FIG. 4, a pipe connecting portion 63 a serving as a discharge port is provided at the rear portion of the actuator pump 63, and one end of a hydraulic pipe 72 is connected to the pipe connecting portion 63 a. Bypasses the right front side portion of the mission case 18 and the other end of the hydraulic pipe 72 is connected to a pipe connecting portion 64 a provided on the right side of the power steering case 64. In this way, the hydraulic piping 72 is less likely to be splashed by mud and the like repelled from below, and the hydraulic oil is also easily cooled.

  An oil filter 80 is provided below the HST pump 62 and the actuator pump 63, and a hydraulic pipe 79 is provided on the front side of the oil filter 80, the HST pump 62 and the actuator pump 63. The hydraulic fluid is supplied from the hydraulic pipe 79 to the HST pump 62 and the actuator pump 63 via the oil filter 80.

  As shown in FIGS. 2 to 4, the power steering case 64 assists the operation of the steering handle 24, and is disposed on the front surface of the mission case 18 and on the upper left and right central surfaces. Attached to. As shown in FIG. 11, the power steering case 64 includes a steering hydraulic valve 64 c and a hydraulic motor 64 d. By operating the steering handle 24, the steering hydraulic valve 64 c is operated and hydraulic oil from the hydraulic pipe 72 is operated. By controlling the flow, the hydraulic motor 64d is driven to assist the operation of the steering handle 24, and the direction of the left and right front wheels 12 can be easily operated with a small operating force.

  The power steering case 64 is connected to the lift valve unit 65 via a hydraulic pipe 73. Specifically, as shown in FIGS. 2 and 4, a pipe connecting portion 64 b capable of supplying pressure oil to another hydraulic device is provided on the upper right side of the power steering case 64, and the hydraulic pipe is connected to the pipe connecting portion 64 b. One end of 73 is connected, and the hydraulic piping 73 bypasses the right side portion of the transmission case 18 and is connected to a piping connecting portion 65 a provided on the upper right side of the lift valve unit 65. The power steering case 64 sends the pressure oil from the hydraulic pipe 72 to the lift valve unit 65 from the hydraulic pipe 73.

  As shown in FIG. 2, the lift valve unit 65 is attached to the rear part of the mission case 18. Specifically, it is arranged on the upper rear surface of the mission case 18 at the center of the left and right sides and attached to the mission case 18. As shown in FIG. 8, the elevating valve unit 65 is detachably attached to the mission case 18 with four bolts 81, and is configured to have good maintainability and assemblability. Further, as shown in FIG. 3, the lift valve unit 65 is disposed so as to be located above the extension portion 18 d and the connection frame 15 extending rearward from the lower portion of the rear portion of the transmission case 18, and lift and lower during traveling. It is configured to prevent mud from being applied to the valve unit 65.

  Further, as shown in FIG. 1, the lift valve unit 65 is disposed below the step 23, and the maintenance of the lift valve unit 65 is facilitated by removing the step 23 or opening a part of the step 23. Configured to be able to do. Further, as shown in FIG. 2, the lifting valve unit 65, which is a heavy object, is disposed at the left and right center position of the mission case 18, that is, at the left and right center position of the rice transplanter 1. Configured to be good.

  The lift valve unit 65 is connected to the lift cylinder 35 via a hydraulic pipe 75. Specifically, a pipe connecting portion 65 b is provided on the upper left and right central sides of the lift valve unit 65, one end of the hydraulic pipe 75 is connected to the pipe connecting portion 65 b, and the other end is on the upper left side of the lift cylinder 35. It connects with the provided piping connection part 35e. Thus, since the lift valve unit 65 is attached to the rear part of the mission case 18, the length of the hydraulic pipe 75 connected to the lift cylinder 35 disposed behind the mission case 18 can be shortened. The elevating valve unit 65 controls the flow of pressure oil to the elevating cylinder 35 and operates the elevating cylinder 35 to elevate the planting unit 40.

  Specifically, as shown in FIG. 11, the lift valve unit 65 includes a control valve 65 f that is a solenoid valve (proportional valve) that controls the flow of pressure oil to the lift cylinder 35, and the control valve 65 f is a solenoid. By controlling the flow of hydraulic oil supplied from the hydraulic pipe 73, the amount of hydraulic oil flowing into the oil chamber 35d of the lift cylinder 35 is adjusted to raise and lower the planting unit 40. The lift valve unit 65 includes a stop valve 65g. The stop valve 65g is interposed between the control valve 65f and the lift cylinder 35, and the planting portion 40 can be moved to an arbitrary height by operating the stop valve 65g. It is configured to be able to stop.

  The elevating cylinder 35 is composed of a hydraulic cylinder, and is composed of a piston rod 35a, a piston 35b fixed to the base end of the piston rod 35a, a cylinder tube 35c that houses the piston 35b, and the like. The inside of the cylinder tube 35c is separated into two chambers on the rod chamber side and the head chamber side by the piston 35b. The oil chamber on the rod chamber side becomes the oil chamber 35d on the rising side of the lifting cylinder 35, and the oil chamber on the head chamber side becomes the oil chamber 35f on the descending side. An accumulator 38 for accumulating hydraulic pressure is inserted into the oil chamber 35d.

  The oil chamber 35d is communicated with a pipe connecting part 35e, and the pipe connecting part 35e is connected with a hydraulic pipe 75. The elevating cylinder 35 is operable by pressure oil from the hydraulic pipe 75. The oil chamber 35f is communicated with a pipe connecting part 35g, and the pipe connecting part 35g is connected with a hydraulic pipe 78. The leaked oil leaked into the oil chamber 35f is returned to the transmission case 18 via the hydraulic piping 78.

  FIG. 7 is a perspective view showing a configuration of the rear portion of the mission case 18 when the elevating valve unit 65 is removed from the mission case 18. The hydraulic pipe 78 is configured to run along the connection frame 15 by a binding band 78a fixed to the right side surface of the connection frame 15, and the front end thereof is connected to a pipe connection part 18c provided below the rear part of the transmission case 18. Is done. The pipe connecting portion 18 c is located below the oil level of the hydraulic oil filled in the mission case 18.

  The elevating valve unit 65 is in communication with the mission case 18. Specifically, as shown in FIG. 9, the elevating valve unit 65 has two communication holes 65 e formed in the contact surface 65 d that contacts the mission case 18, and the mission case 18 is formed as shown in FIG. 10. Two communication holes 18f are formed in the contact surface 18e that contacts the contact surface 65d. The communication holes 65e and 18f are communicated to return the hydraulic oil from the lift valve unit 65 to the mission case 18. At this time, the hydraulic oil is configured to be returned below the oil level of the hydraulic oil filled in the mission case 18. In this manner, the elevating valve unit 65 has a communication hole 65e for returning the hydraulic oil to the contact surface 65d that contacts the transmission case 18, and the communication hole 65e communicates with the communication hole 18f of the transmission case 18. Since hydraulic fluid is returned, the hydraulic piping which connects the raising / lowering valve unit 65 and the transmission case 18 becomes unnecessary. The communication hole 65e is located below the oil level of the hydraulic oil filled in the mission case 18. A plurality of relief valves 65h are interposed between one communication hole 65e and the control valve 65f in the lift valve unit 65 (see FIG. 11).

  As shown in FIG. 11, the elevating valve unit 65 is connected to the horizontal control valve unit 66 through a hydraulic pipe 76. Specifically, a pipe connecting part 65 c is provided on the upper left side of the lift valve unit 65, one end of the hydraulic pipe 76 is connected to the pipe connecting part 65 c, and the other end is provided above the horizontal control valve unit 66. Connected to the pipe connecting portion. The elevating valve unit 65 includes a flow divider 65 i for distributing hydraulic oil, and supplies the distributed hydraulic oil to the horizontal control valve unit 66 from the hydraulic pipe 76.

  As shown in FIG. 1, the horizontal control valve unit 66 is provided at the rear portion of the elevating link mechanism 34. As shown in FIG. 11, the horizontal control valve unit 66 includes a horizontal control solenoid valve 66a, and is provided integrally with the horizontal control valve unit 66 by switching the horizontal control solenoid valve 66a. The horizontal cylinder 67 is expanded and contracted to control the planting unit 40 to be horizontal. The planting unit 40 is provided with an inclination sensor. When the planting unit 40 is tilted from the horizontal position, the solenoid valve 66a for horizontal control is switched, and the horizontal cylinder 67 is expanded or contracted. It is controlled to keep 40 horizontal.

  The horizontal control valve unit 66 is connected to the mission case 18 via a hydraulic pipe 77. Specifically, a pipe connecting portion serving as a drain port is provided at the upper part of the horizontal control valve unit 66, one end of the hydraulic pipe 77 is connected to the pipe connecting part, and the other end is located at the rear part of the transmission case 18. It connects with the piping connection part 18b (refer FIG. 8) provided in this. The horizontal control valve unit 66 is configured to return the hydraulic oil of the horizontal cylinder 67 from the hydraulic pipe 77 to the transmission case 18. The hydraulic pipes 75, 76 and 77 are configured so that the hydraulic system becomes compact by bundling them with a binding band or the like.

  According to the rice transplanter 1 having such a configuration, as shown in FIG. 2, the HST 61 serving as a heat source is separated from the lift valve unit 65. Similarly, the power steering case 64 is also arranged at an appropriate interval from the HST 61 serving as a heat source. Thereby, the temperature rise of the hydraulic fluid which flows into the raising / lowering valve unit 65 and the power steering case 64 can be suppressed. Accordingly, the amount of hydraulic oil can be reduced, the hydraulic oil can be deteriorated, and the number of hydraulic oil replacements can be reduced. Further, the cooling of the hydraulic system can be reduced, and the cost can be reduced.

  As described above, in the rice transplanter 1 according to an embodiment of the present invention, the actuator pump 63 serving as a hydraulic pump driven by the power of the engine 14 and the hydraulic oil supplied to the actuator pump 63 are satisfied. A transmission case 35, a lifting cylinder 35 that is disposed behind the mission case 18 and that raises and lowers the planting portion 40 by sending pressure oil from the actuator pump 63. In the rice transplanter 1 including a lift valve unit 65 having a control valve 65f for controlling the flow of hydraulic oil, the lift valve unit 65 is attached to the rear portion of the transmission case 18. Thereby, the length of the hydraulic piping that connects the lift valve unit 65 and the transmission case 18 and the hydraulic piping that connects the lift valve unit 65 and the lift cylinder 35 can be shortened. Therefore, the space occupied by the hydraulic piping can be reduced, and the hydraulic system becomes compact.

  Further, the elevating valve unit 65 is formed with a communication hole 65e for returning the hydraulic oil to a contact surface 65d that contacts the transmission case 18. This eliminates the need for piping connecting the elevating valve unit 65 and the transmission case 18 and makes the hydraulic system more compact.

  Further, the elevating valve unit 65 is disposed below the step 23. Thereby, maintenance of the raising / lowering valve unit 65 can be easily performed by removing step 23 or opening a part of step 23.

  Further, an HST 61 for shifting the power of the engine 14 is provided, and the HST 61 is disposed in the front portion of the mission case 18. Accordingly, the lift valve unit 65 is separated from the HST 61 serving as a heat source, and the temperature rise of the hydraulic oil flowing through the lift valve unit 65 can be suppressed. Accordingly, the amount of hydraulic oil can be reduced, the hydraulic oil can be deteriorated, and the number of hydraulic oil replacements can be reduced.

  In addition, an oil cooler 84 for cooling the HST 61 is disposed on a side portion of the radiator 82. Thereby, the cooling efficiency of HST61 can be improved.

  Below, the structure regarding the control which changes the traveling speed of the rice transplanter 1 is demonstrated using FIG.

  The speed change pedal 26 is an operation tool for changing the traveling speed of the rice transplanter 1, and more specifically, an operation tool for changing a rotation angle of a speed change motor 91 described later. The transmission pedal 26 is disposed on the lower right side of the dashboard 21. The shift pedal 26 is configured such that its operation amount can be detected by a shift pedal potentiometer 26a. The shift pedal potentiometer 26 a is connected to the control device 90 and transmits a detection signal to the control device 90.

  The speed change motor 91 changes the rotation speed of the engine 14, changes the speed ratio of the HST 61, changes the connection / disconnection of the main clutch, and changes the operation of the braking device. The speed change motor 91 has a speed control device 14a whose output shaft adjusts the rotational speed of the engine 14 via a link mechanism, a speed change arm 61e that changes the angle of the movable swash plate of the HST 61, and a clutch that turns on and off the main clutch. The arm 27 and the brake arm 28 for braking the braking device are connected. The transmission motor 91 is connected to the control device 90 and is driven and controlled based on a signal transmitted from the control device 90.

  The control device 90 controls the transmission motor 91. The control device 60 is provided at an arbitrary position of the traveling unit 10. Specifically, the control device 60 may be configured such that a CPU, a ROM, a RAM, an HDD, and the like are connected by a bus, or may be configured by a one-chip LSI or the like. The control device 60 stores in advance various programs and maps for controlling the operation of the transmission motor 91. The control device 90 drives and controls the transmission motor 91 based on the detected value of the shift pedal potentiometer 26a and the various programs and maps.

  In the rice transplanter 1 configured as described above, when the speed change motor 91 is damaged due to flooding or the like and cannot move, traveling becomes impossible. Therefore, according to the rice transplanter 1, not only the speed change motor 91 but also a rotating shaft that constitutes a part of the link mechanism can be manually rotated in an emergency. Below, the structure is demonstrated using FIGS. 13-15.

  As shown in FIG. 13, the transmission motor 91 is covered with a motor case 100. The motor case 100 is provided inside a left cover body 9 disposed on the left side below the dashboard 21 (see FIG. 1), and the left cover body 9 is configured to be easily removable without using a tool or the like. Is done.

  The motor case 100 is formed of a left case 100L on the left side and a right case 100R on the right side, and a manual operation shaft 101 serving as the rotation shaft protrudes leftward from the left case 100L. As shown in FIG. 14, a manual operation shaft 101 is fitted with a cylindrical tube shaft 102 so as to be relatively rotatable so that the manual operation shaft 101 and the tube shaft 102 have a double shaft structure. ing. A nut 104 is fixed to the left end portion of the cylindrical shaft 102, and a drill hole 102 a is formed coaxially with the nut 104. At the left end portion of the manual operation shaft 101, an engagement portion 101a is drilled coaxially with the drill hole 102a of the cylindrical shaft 102.

  As shown in FIG. 14A, in a normal time when the speed change motor 91 can operate, the bolt 103 is inserted into the nut 104 and the hole 102 a, and the tip of the bolt 103 is connected to the manual operation shaft 101. It abuts on the engaging portion 101a. That is, the manual operation shaft 101 and the cylindrical shaft 102 are connected to each other so as to be integrally rotatable.

  A fan-shaped sector gear 105 is fixed in the middle of the cylindrical shaft 102, and a tooth portion provided on the outer periphery of the sector gear 105 meshes with a gear provided on the output shaft of the transmission motor 91. . One end of an L-shaped transmission gear 106 is fixed at the right end of the manual operation shaft 101, and the front end of the rod 107 is fixed at a bent portion of the transmission gear 106. The rear end of the rod 107 is connected to the speed change arm 61e, the clutch arm 27, and the brake arm 28 (see FIG. 12).

  The sector gear 105 is provided with a cam groove extending in the circumferential direction, and a transmission shaft slidably fitted in the cam groove is connected to one end of a connecting member. The other end of the connecting member is connected to one end of the operation arm 108 shown in FIG. The other end of the operation arm 108 is connected to the speed governor 14a of the engine 14 through a wire 109 or the like.

  Then, as shown in FIG. 14B, when the speed change motor 91 is inoperable, the bolt 103 is loosened from the nut 104 and the connection between the manual operation shaft 101 and the cylindrical shaft 102 is released. Then, after attaching the auxiliary arm 110 to the left end 101b of the manual operation shaft 101, the auxiliary arm 110 is operated to operate the transmission arm 61e, the clutch arm 27, and the brake arm 28. At this time, since the auxiliary arm 110 can be operated with the left hand and the steering handle 24 can be operated with the right hand, the escape operation from the farm field or the like can be performed while sitting in the driver's seat 22.

  Further, as shown in FIG. 15, a shift gauge 100a is provided in the vicinity of the position where the manual operation shaft 101 protrudes on the surface of the left case 100L. The shift gauge 100a indicates a rotation range of the bolt 103 due to the rotation of the manual operation shaft 101 when connected in a left side view. In the present embodiment, the transmission gauge 100a is arranged on the left side from the position where the manual operation shaft 101 protrudes. As described above, since the shift gauge 100a is provided, the gear ratio of the HST 61 can be known and adjusted easily depending on which part of the shift gauge 100a the bolt 103 is located. Further, the shift gauge 100a serves as a guide for the amount of operation of the manual operation shaft 101 when the connection is released. Note that a clutch ON position 100b where the main clutch is ON is formed in the transmission gauge 100a.

1 Rice transplanter 14 Engine 18 Mission case 23 Step 35 Lift cylinder 40 Planting part 61 HST
63 Actuator pump (hydraulic pump)
65 Lifting valve unit 65d Contact surface 65e Communication hole 65f Control valve 82 Radiator 84 Oil cooler

Claims (5)

A hydraulic pump driven by the power of the engine;
A mission case filled with hydraulic oil supplied to the hydraulic pump;
An elevating cylinder that is arranged behind the mission case and raises and lowers the planting part by sending pressure oil from the hydraulic pump,
A lifting valve unit having a control valve for controlling the flow of pressure oil to the lifting cylinder;
In rice transplanter with
A rice transplanter, wherein the lift valve unit is attached to a rear portion of the mission case.   2. The rice transplanter according to claim 1, wherein the elevating valve unit is formed with a communication hole for returning hydraulic oil on a contact surface that contacts the transmission case.   The rice transplanter according to claim 1 or 2, wherein the elevating valve unit is arranged below a step. An HST for shifting the power of the engine;
The rice transplanter according to any one of claims 1 to 3, wherein the HST is disposed in a front portion of the mission case.   The rice transplanter according to claim 4, wherein an oil cooler for cooling the HST is disposed on a side portion of the radiator.

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