JP6533091B2 - Farm work vehicle - Google Patents

Description

  The present invention relates to an agricultural work vehicle such as a speed sprayer that performs chemical liquid dispersion in an orchard or the like.

  Conventionally, a speed sprayer, which is an example of an agricultural work vehicle, is configured to supply and disperse a chemical solution from a chemical solution tank mounted on a traveling vehicle via a power spray pump to a spray nozzle of a chemical solution spraying unit (for example, 1 and 2). This type of speed sprayer includes a suspension system for suspending an axle case on an airframe frame. For example, a suspension system provided in a speed sprayer described in Patent Document 1 includes a compression spring and a damper for damping ground reaction forces from the left and right wheels. In this case, a large impact component of the ground reaction force is absorbed by the compression spring, and a small impact component such as repeated vibration is damped by the damper to secure the ride quality and running performance of the speed sprayer.

JP, 2013-248929, A Patent No. 4718663 gazette

  However, in the suspension system described in Patent Document 1, since the initial spring length of the compression spring is always constant, the vehicle load (spring load) fluctuates according to the amount of chemical solution in the chemical solution tank, and the vehicle height of the traveling vehicle Up and down. For this reason, at the time of chemical liquid dispersion work in orchards etc., the amount of chemical liquid in the chemical liquid tank decreases and the height of the traveling machine body rises, and the traveling machine body may come in contact with the branches of trees and cause fruits to fall carelessly there were.

  The present invention has been made as a technical subject to provide an agricultural work vehicle which has been improved by examining the above-mentioned current situation.

The invention according to claim 1 is an agricultural work vehicle including an airframe frame constituting a traveling airframe, an axle case supporting left and right wheels, and a suspension system for suspending the axle case on the airframe frame, the suspension system comprising A compression spring and a damper for attenuating a ground reaction force from both wheels, a spring seat that abuts one end of the compression spring, and an actuator for moving the spring seat along the expansion and contraction direction of the compression spring; And a controller for driving the actuator based on detection information of the detector , wherein the spring seat body extends along the expansion and contraction direction of the compression spring. The position is changeable , and the position is changed according to the amount of the mounted object mounted on the traveling body .

The invention of claim 2 is that, in the agricultural work vehicle according to claim 1 , the traveling machine body is equipped with a chemical solution tank for storing a chemical solution, and the detector detects the amount of chemical solution in the chemical solution tank. .

According to the present invention, there is provided an agricultural work vehicle comprising an airframe frame constituting a traveling airframe, an axle case supporting left and right wheels, and a suspension device for suspending the axle case on the airframe frame. A compression spring and a damper for attenuating a ground reaction force from a wheel, a spring seat body abutting on one end side of the compression spring, an actuator for moving the spring seat body along an extension direction of the compression spring A detector for detecting an amount of a mounted object mounted on an airframe, and a control device for driving the actuator based on detection information of the detector , wherein the spring seat changes the position along the expansion and contraction direction of the compression spring capable constructed, and because the position changing in response to the mounting amount mounted on the traveling machine body, the movement of the spring seat member along the stretch direction of the compression spring Te, can adjust the initial spring length and thus the urging force of the compression spring, it is possible to adjust the vehicle height of the traveling machine body in consideration of the body weight (sprung weight).

Further, since the position of the spring seat is changed according to the amount of the mounted object mounted on the traveling machine body, the position of the spring seat is changed in conjunction with the change of the amount of the mounted object, That is, the vehicle height of the traveling airframe can be kept constant regardless of the change in the vehicle body load (spring load).

It is a left side view of the speed sprayer in an embodiment. It is a top view of a speed sprayer. It is a top view of the inside of a cabin. It is a schematic plan view of a steering system. It is a power transmission system diagram of a speed sprayer. It is a schematic explanatory drawing of an engine and a pressure accumulation type fuel injection device. It is the perspective view which looked at the suspension apparatus from the front upper side. It is the perspective view which looked at the suspension apparatus of the state which abbreviate | omitted the body frame from the front upper side. It is the perspective view which looked at the suspension apparatus from the back lower side. It is a top view of a suspension system. It is side surface sectional drawing of a suspension apparatus. It is a functional block diagram of a controller. It is a flowchart of vehicle height adjustment control. It is a functional block diagram of the controller in another example.

  Hereinafter, an embodiment of the present invention will be described based on the drawings when it is applied to a speed sprayer as a farm work vehicle.

  First, the outline of the speed sprayer will be described with reference to FIGS. 1 to 3. The traveling body 1 of the speed sprayer in the embodiment is supported by a pair of left and right front wheels 3 as a traveling portion and a pair of left and right rear wheels 4 as well. A cabin 5 is disposed at the front of the traveling vehicle 1. In the rear of the cabin 5 in the traveling machine 1 (in the front and rear midway portion of the traveling machine 1), a chemical solution tank 6 for storing a chemical solution is disposed. An engine room 7 is disposed behind the chemical liquid tank 6 in the traveling body 1. In the engine compartment 7, a diesel engine 8 (hereinafter simply referred to as an engine) and a power spray pump 9 are mounted. At the rear of the engine 8, a PTO transmission case 20 for transmitting the power from the engine 8 to the power spray pump 9 and the like is attached. The chemical solution spray unit 10 and the blower fan 11 are disposed at the rear of the traveling body 1 (rear of the engine room 7). Below the chemical solution tank 6, a traveling transmission case 12 for shifting the power from the engine 8 is mounted. The power spray pump 9 and the blower fan 11 are driven by the power of the engine 8, and the drug solution is sucked from the drug solution tank 6 by the power spray pump 9 and the drug solution is sprayed from the drug solution spray unit 10. The sprayed chemical solution is diffused into a field such as an orchard by air blowing from the blower fan 11 and dispersed to a fruit tree or the like.

  A front axle case 13 is provided at the front lower portion of a substantially well-gage body frame 2 constituting the traveling body 1. The front wheels 3 are rotatably mounted on the left and right sides of the front axle case 13. A rear axle case 14 is provided at the rear lower portion of the airframe 2. Rear wheels 4 are rotatably mounted on the left and right sides of the rear axle case 14. The traveling transmission case 12 is power transferably connected to the front axle case 13 via a front wheel transmission shaft 15 extending forward, and is power transferably connected to the rear axle case 14 via a rear wheel transmission shaft 16 extending rearward. doing. The power transmitted from the engine 8 through the PTO transmission case 20 is changed by the traveling transmission case 12 and the right and left front wheels 3 are driven via the front wheel transmission shaft 15 and the front axle case 13 by the transmission output. The left and right rear wheels 4 are driven via the rear axle case 14 (four-wheel drive is possible).

  As shown in FIG. 2 and FIG. 3, inside the cabin 5, a steering seat 21 on which an operator is seated and a steering handle 22 for steering the left and right front wheels 3 or the front and rear four wheels 3, 4 are disposed. . An instrument panel 24 for displaying an engine tachometer, a fuel gauge, and the like is disposed on the upper rear side of the dashboard 23 disposed in front of the steering handle 22. On the rear right side of the dashboard 23, a two-wheel steering mode switch 25 and a four-wheel steering mode switch 26 for switching between the left and right front wheels 3 and both left and right rear wheels 4 to two-wheel steering mode and four-wheel steering mode And a throttle lever 29, which is a rotational speed operation tool for setting and holding the speed setting unit. Each mode switch 25, 26 is a switch with a lamp. In the following description, for convenience, the two-wheel steering mode is described as a 2WS mode, and the four-wheel steering mode is described as a 4WS mode.

  Below the dashboard 23, there is an accelerator pedal 30, which accelerates and decelerates the engine rotational speed based on the rotational speed set by the throttle lever 29, a brake pedal 31, which brakes the traveling body 1, and traveling for power transmission / reception. A clutch pedal 32 for connecting and disconnecting the clutch 84 (see FIG. 5) is disposed. On the side column 33 provided on the left side of the operation seat 21, the parking brake lever 34 for maintaining the left and right rear wheels 4 in the braking state, and the drive system of the front wheels 3 and the rear wheels 4 are switched to 2nd and 4th wheels. The drive switching lever 35 to operate, the main transmission lever 36 to operate forward, stop, reverse and the vehicle speed of the traveling body 1 and the auxiliary transmission operating tool to switch the output of the traveling mission case 12 between low speed and high speed The shift lever 37 is disposed.

  As shown in FIGS. 2 and 4, the front axle case 13 is provided with a front wheel steering cylinder 41 that changes the direction of the left and right front wheels 3. Regardless of whether the 2WS mode or the 4WS mode is performed, the left and right front wheels 3 can be kingpin 44 via the tie rod 42 and the knuckle arm 43 by causing the front wheel steering cylinder 41 to extend and retract according to the turning operation of the steering handle 22. Turn around (turn) in the same direction. That is, the steering angles (steering angles) of the left and right front wheels 3 are changed in proportion to the steering angle (rotational operation amount) of the steering wheel 22.

  Further, the rear axle case 14 is provided with a rear wheel steering cylinder 45 for changing the direction of the left and right rear wheels 4. When the 4WS mode is performed, the left and right rear wheels 4 are equally rotated around the king pin 48 through the tie rod 46 and the knuckle arm 47 by extending and contracting the rear wheel steering cylinder 45 according to the turning operation of the steering handle 22. Turn the direction (turn). That is, the steering angles (steering angles) of the left and right rear wheels 4 are changed in proportion to the steering angle (rotational operation amount) of the steering handle 22. In this case, the steering angles of the left and right rear wheels 4 are in opposite phase to the steering angles of the left and right front wheels 3.

  Next, the power transmission system of the speed sprayer will be described mainly with reference to FIG. The flywheel housing 71 is fixed to the rear surface side of the cylinder block 50 (see FIGS. 8 and 10 to 12). A flywheel 72 is disposed in the flywheel housing 71. A flywheel 72 is directly connected to a rear end side of an engine output shaft 70 which projects forward and backward from the engine 8. The power of the engine 8 is taken out via the flywheel 72. The PTO transmission case 20 is detachably mounted on the rear side of the flywheel housing 71. A flywheel 72 is connected to a mission input shaft 73 in the PTO mission case 20. The PTO transmission case 20 of the embodiment projects from the engine 8 downward to the right. A main driving shaft 74 for transmitting power to the traveling transmission case 12 and a pump PTO shaft 75 for driving the power spray pump 9 protrude forward from the overhanging portion of the PTO transmission case 20. Further, a fan PTO shaft 76 for driving the blower fan 11 protrudes rearward from the PTO transmission case 20. The PTO transmission case 20 constitutes a power takeout portion for taking out the power of the engine 8 through the flywheel 72.

  In the PTO transmission case 20, the transmission input shaft 73 described above, the main transmission gear mechanism 77 for transmitting the power transmitted to the transmission input shaft 73 to the main driving shaft 74 and the PTO shaft for pump 75, and the transmission input shaft 73. An auxiliary transmission gear mechanism 78 is disposed for transmitting the motive power to the fan PTO shaft 76 via the fan clutch mechanism 79. The power from the engine 8 is split and transmitted to a system directed from the transmission input shaft 73 to the main transmission gear mechanism 77 and to a system directed from the transmission input shaft 73 to the auxiliary transmission gear mechanism 78. The power transmitted to the main transmission gear mechanism 77 is further branched and transmitted to a system directed to the main drive shaft 74 and a system directed to the pump PTO shaft 75. The power transmitted from the main transmission gear mechanism 77 to the pump PTO shaft 75 is transmitted to the pump shaft (not shown) of the power spray pump 9 through the pulley and belt transmission system 80 to drive the power spray pump 9. The auxiliary transmission gear mechanism 78 is configured to be switchable in two stages of high speed and low speed. The power transmitted from the transmission input shaft 73 to the auxiliary transmission gear mechanism 78 via the fan clutch mechanism 79 is appropriately shifted by the auxiliary transmission gear mechanism 78 and transmitted to the fan PTO shaft 76 to drive the blower fan 11.

  The traveling transmission case 12 located in front of the engine 8 and below the chemical solution tank 6 has a main transmission input shaft 82 receiving power from the main drive shaft 74 via a transmission shaft 81 having universal shaft joints at both ends, and the inside of the chemical solution tank 6 A stirring PTO shaft 83 for driving a stirring blade (not shown) and a travel output shaft 17 for transmitting power to the front wheel transmission shaft 15 and the rear wheel transmission shaft 16 are provided. The main transmission input shaft 82 projects rearward from the traveling transmission case 12, and the main driving shaft 74 projecting forward from the overhanging portion of the PTO transmission case 20 transmits power to the main transmission input shaft 82 via the transmission shaft 81. The stirring PTO shaft 83 projects forward from the traveling mission case 12. The travel output shaft 17 protrudes from both front and rear sides of the travel transmission case 12. A front wheel transmission shaft 15 is connected to the front end side of the traveling output shaft 17 via a universal shaft joint, and a rear wheel transmission shaft 16 is connected to the rear end side of the traveling output shaft 17 via the universal shaft joint.

  In the traveling transmission case 12, a traveling clutch 84 for power connection and a main transmission shaft 85 connected to the front end side of the main transmission input shaft 82 (a part in the traveling transmission case 12) via the traveling clutch 84 A main transmission gear mechanism 86 and an auxiliary transmission gear mechanism 87 for shifting the power passing through the PTO transmission case 20, and the stirring PTO shaft 83 and the travel output shaft 17 described above are disposed. The power transmitted from the main shift input shaft 82 to the main shift transmission shaft 85 via the traveling clutch 84 is split and transmitted to a system directed to the stirring PTO shaft 83 and a system directed to the main shift gear mechanism 86. The power transmitted from the main transmission transmission shaft 85 to the stirring PTO shaft 83 is transmitted to the stirring shaft (not shown) of the stirring blade in the chemical solution tank 6 via the pulley and belt transmission system 88 to drive the stirring blade. . The power traveling from the main transmission transmission shaft 85 to the main transmission gear mechanism 86 is appropriately shifted by the main transmission gear mechanism 86 and the auxiliary transmission gear mechanism 87, and then transmitted to the travel output shaft 17. The transmission power transmitted to the traveling output shaft 17 is transmitted to the front wheel differential gear mechanism 18 in the front axle case 13 via the front wheel transmission shaft 15 to drive the left and right front wheels 3 and the rear wheel transmission shaft 16. And is transmitted to the rear wheel differential gear mechanism 19 in the rear axle case 14 to drive the left and right rear wheels 4.

  Next, the engine 8 and the peripheral structure thereof will be described with reference to FIGS. The engine 8 mounted on the traveling body 1 includes a cylinder block 50 in which a cylinder head 51 is fastened on the upper surface. An exhaust manifold 52 is provided on one side surface of the cylinder head 51. A diesel particulate collection filter 54 (hereinafter referred to as a collection filter), which is an aftertreatment device, is connected to the exhaust pipe 53 connected to the exhaust port side of the exhaust manifold 52. The collection filter 54 is for collecting particulate matter (PM) and the like in the exhaust gas. Although not shown, the collection filter 54 of the embodiment has a structure in which an oxidation catalyst such as platinum and a honeycomb structure are arranged in series in a substantially cylindrical filter case in a casing made of a heat resistant metal material. It has become. Exhaust gas discharged from each cylinder of the engine 8 to the exhaust manifold 52 is purified through the collection filter 54 and then released out of the machine.

  As shown in FIG. 6 etc., the engine 8 is provided with a pressure accumulation type fuel injection device 55 (common rail type fuel injection device) which is a fuel supply means. The accumulator fuel injection device 55 includes a plurality of injectors 56 (fuel injection valves) for injecting high-pressure fuel to each cylinder of the engine 8 and a common rail 57 (accumulator chamber) for accumulating high-pressure fuel and distributing it to the injectors 56. A supply pump 60 is provided which pressurizes the fuel sucked from the fuel tank 58 mounted on the traveling body 1 via the fuel filter 59 to a high pressure and pressure-feeds it to the common rail 57.

  Each injector 56 is connected to the common rail 57 via a separate high pressure pipe 61. While each injector 56 is open, high pressure fuel pumped from the common rail 57 is injected toward the combustion chamber of each cylinder. A pressure sensor 62 for detecting an internal pressure (fuel pressure in the common rail 57) is attached to the common rail 57. The supply pump 60 is driven by the power of the engine 8 and has a pressure control solenoid valve 63 for adjusting the amount of fuel delivery to the common rail 57. The pressure control solenoid valve 63 adjusts the amount of fuel pumping to the common rail 57 by controlling the amount of fuel return from the supply pump 60 to the fuel tank 58 to control the common rail internal pressure. The fuel injection pressure of each injector 56 is approximately equal to the common rail internal pressure. Therefore, the control of the common rail internal pressure by the pressure control solenoid valve 63 indirectly controls the injection pressure of each injector 56.

  Each injector 56, the common rail 57 and the supply pump 60 are connected to the fuel tank 58 via a return pipe 64. A pressure limiter valve 65 is provided between the common rail 57 and the return pipe 64 to prevent the internal pressure of the common rail from increasing more than necessary. A pressure control solenoid valve 63 is provided between the supply pump 60 and the return pipe 64. Excess fuel in each injector 56, common rail 57 and supply pump 60 is returned to the fuel tank 58 through the return pipe 64.

  The accumulator fuel injection device 55 executes main injection in the vicinity of the top dead center (TDC). In addition to the main injection, the accumulator-type fuel injection device 55 performs a small amount of pilot injection for the purpose of reducing NOx and noise at a timing about 60 ° before the top dead center or for noise reduction. Pre-injection is performed immediately before top dead center, or after injection and post injection are performed after top dead center for the purpose of reduction of particulate matter and purification of exhaust gas.

  Next, the detailed structure of the suspension device 110 for suspending the front axle case 13 on the airframe frame 2 will be described with reference to FIGS. 7 to 11. The airframe 2 includes a pair of left and right front frames 101 formed in a reverse U-shape in side view. The left and right front frames 101 are connected by a plurality of laterally long beam frames 102. The left and right front frames 101 and the end of each beam frame 102 are fixed by welding. The left and right front frames 101 straddle the front axle case 13 from above. In other words, the front axle case 13 is located in the inverted U-shaped recessed portion of the left and right front frame 101.

  At the lower part between the left and right front frames 101, a swing plate 103 is disposed which supports the front axle case 13 so as to be able to swing up and down. At the rear of the rocking plate 103, a bifurcated arm portion 104 extending rearward is provided. The rear end side of the corresponding arm portion 104 is rotatably supported at the rear inner surface side of the left and right front frames 101. The pivot axes of the two arm portions 104 are located on the same axis extending in the left-right direction. Accordingly, the rocking plate 103 can be rocked up and down with the rear end sides of the two arm portions 104 as a fulcrum.

  The front portion of the rocking plate 103 extends so as to cover the front of the front axle case 13. At a front portion of the swing plate 103, a front fulcrum 105 projecting forward from a left and right intermediate portion on the front side of the front axle case 13 is rotatably supported. On the other hand, a relay shaft 106 for transmitting power to the front wheel differential gear mechanism 18 in the front axle case 13 is provided to project rearward at a left and right intermediate portion on the rear surface side of the front axle case 13. Of the front axle case 13, a boss portion 107 for pivotally supporting the relay shaft 106 is pivotally supported by a fulcrum receiver 108 after being bolted to the lower surface side of the swing plate 103. The front fulcrum 105 and the bosses 107 (including the relay shaft 106) of the front axle case 13 are located on the same axis extending in the front-rear direction. Therefore, the front axle case 13 is vertically rotatable (rolling movement) with the left and right middle portions (the front support body 105 and the boss portion 107 of the front axle case 13) as a support point. When there is a difference in the contact pressure of the left and right front wheels 3, the front axle case 13 pivots up and down around the left and right intermediate portions, and the left and right front wheels 3 ascend and descend in opposite directions. As a result, the contact pressure of the left and right front wheels 3 is maintained substantially equal.

  It is needless to say that the front axle case and the left and right front wheels 3 can be rocked up and down with the rocking plate 103 with the rear end sides of the both arm portions 104 as supporting points. The relay shaft 106 is connected to the front end side of the front wheel transmission shaft 15 via a universal joint. The rotational power transmitted to the front wheel transmission shaft 15 is transmitted to the front wheel differential gear mechanism 18 in the front axle case 13 via the relay shaft 106.

  In the upper part between the left and right front frames 101, a gate-shaped frame 109 having a substantially gate-shaped front view is provided. A pair of left and right suspension devices 110 are disposed between the portal frame 109 and the swing plate 103. Each suspension system 110 includes a compression spring 111 and a damper 112 for attenuating the ground reaction force from the left and right front wheels 3 via the front axle case 13, and an upper spring seat 113 abutting on the upper end side (one end side) of the compression spring 111. And have.

  In the embodiment, a pair of left and right through holes are formed in the upper surface plate of the portal frame 109, and a damper bracket 114 having a U-shaped cross section is erected around each through hole. The damper 112 is inserted into each through hole, and the cylinder side end of the damper 112 is rotatably connected to the upper side of the damper bracket 114 by a horizontally long pivot pin 115. The swing plate 103 is provided with a pair of lower spring seats 116 corresponding to the through holes on the portal frame 109 side. A through hole is formed in each lower spring seat portion 116, and the rod end of the corresponding damper 112 is inserted. The rod side end of each damper 112 is rotatably connected to the lower surface side of the swing plate 103 by a horizontally long pivot pin 117.

  The compression spring 111 is fitted on the outer peripheral side of the damper 112. The compression spring 111 is located between the top plate of the portal frame 109 and the lower spring seat 116 of the swing plate 103. An upper spring seat 113 that abuts on the upper end side of the compression spring 111 is fitted below the upper surface plate of the portal frame 109 among the dampers 112. The lower end side (other end side) of the compression spring 111 is fitted in the lower spring seat portion 116 of the swing plate 103.

  The large impact component of the ground reaction force from the left and right front wheels 3 through the front axle case 13 is absorbed by the left and right compression springs 111, and is a relative vibration between the upper spring seat 113 and the lower spring seat 116 The small impact component such as is damped by the left and right dampers 112 to secure the ride quality and the running performance of the speed sprayer.

  The upper spring seat body 113 of each suspension device 110 is configured to be positionally changeable along the expansion and contraction direction (vertical direction) of the compression spring 111. Each upper spring seat 113 of the embodiment is attached with a rear arm 118 extending rearward and a front arm 119 extending forward. A bifurcated pivot bracket 120 is fixed by welding on the third beam frame 102 above the arm portion 104 of the swing plate 103. The front end side (rear end side) of the rear arm 118 is pivotably connected to the pivot bracket 120 on the third beam frame 102 by means of a laterally oriented connection pin 121. Accordingly, the upper spring seat body 113 can be changed in position along the expansion and contraction direction (vertical direction) of the compression spring 111 by pivoting up and down around the connection pin 121.

  An electric cylinder 122 as an actuator is disposed between the front end of the forearm 119 and the second beam frame 102 in front of the swing plate 103. The cylinder side end of the electric cylinder 122 is rotatably connected to the end of the front arm 119 by a horizontal axis pin 123. A bifurcated support bracket 124 is fixed on the second beam frame 102 by welding. The rod-side end of the electric cylinder 122 is pivotally connected to the support bracket 124 on the second beam frame 102 by a horizontal axis pin 125. The electric cylinder 122 is a so-called ball screw type, and the rod of the electric cylinder 122 moves forward and backward (the electric cylinder 122 extends and contracts) by rotating the electric motor 131 (see FIG. 12) to be described later. Configured.

  The upper spring seat body 113 is pivoted up and down around the connection pin 121 by the expansion and contraction movement of the electric cylinder 122, and the position is changed along the expansion and contraction direction (vertical direction) of the compression spring 111. As a result, the initial spring length of the compression spring 111 and hence the biasing force are adjusted, and the vehicle height of the traveling body 1 is adjusted. In the embodiment, when the upper spring seat body 113 pivots downward around the connection pin 121, the vehicle height of the traveling machine body 1 increases, and when the upper spring seat body 113 pivots upward around the connection pin 121, the traveling vehicle body The height of the car becomes lower.

  A pair of left and right rolling restricting members 141 for restricting the rolling range around the left and right middle portions of the front axle case 13 is provided on the lower surface side of the front of the rocking plate 103 in the left and right. The rolling restricting body 141 is made of an elastic material such as rubber, and the left and right middle portions of the front axle case 13 are brought into contact by the left and right rolling restricting bodies 141 coming into contact with the restricting brackets 142 attached to the inner surface side of the left and right front frames 101. Rolling movement around is limited. A swing restricting body 144 is provided on the outer surface side of the left and right front frames 101 via a mounting bracket 143 which protrudes outward in the left and right direction. The rocking restricting body 144 is made of an elastic material such as rubber as the rolling restricting body 141, and the left and right rocking restricting bodies 144 abut on contact blocks 145 provided on the left and right sides of the front axle case 13. The upward movement of the front axle case 13 (upward swinging with the rear end sides of both arms 104 of the swing plate 103 as the fulcrum) is limited.

  Next, the configuration for executing the vehicle height adjustment control and the control mode thereof will be described with reference to FIGS. 12 and 13. As shown in FIG. 12, the traveling machine body 1 is equipped with a controller 130 as a control device that controls the overall operation control of the speed sprayer. Although not shown in detail, the controller 130 includes a CPU for executing various arithmetic processing and control, a ROM for storing control programs and data, a RAM for temporarily storing control programs and data, and It has an input / output interface etc.

  The controller 130 includes each injector 56 of the pressure accumulation type fuel injection device 55, a pressure sensor 62 for detecting the common rail internal pressure, a pressure control solenoid valve 63 for adjusting the fuel pumping amount to the common rail 57, and a rotational speed detection for detecting the engine rotational speed. Rotation sensor 66 as an accelerator, an accelerator sensor 67 for detecting the depression amount (operation amount) of the accelerator pedal 30, a throttle potentiometer 68 for detecting the operation position of the throttle lever 29, an electric motor for advancing and retracting the rods of the respective electric cylinders 122 131 A motor driver 132 for driving 131, a rotation angle sensor 133 as an operation detector provided to each electric motor 131, a pump switch 134 for turning on and off driving of the power spray pump 9, and a fan switch for turning on and off driving of the blower fan 11. 135, and chemical liquid tank Chemical amount in 6 connects the chemical solution amount sensor 136 such as a detector for detecting (mountable amount).

  The rotation angle sensor 133 detects the rod protrusion amount of the electric cylinder 122 from the rotation angle of the motor shaft of the electric motor 131. The pump switch 134 and the fan switch 135 are disposed on the rear left side of the dashboard 23 in the cabin 5. The chemical amount sensor 136 is a float type, and is disposed in the chemical tank 6. In this case, the amount of chemical solution in the chemical solution tank 6, and hence the machine load (spring load) is detected based on the change in the vertical height position of the chemical solution amount sensor 136.

  The controller 130 drives the pressure control solenoid valve 63 based on the detection result of the pressure sensor 62 so as to obtain an appropriate common rail internal pressure according to the drive state of the engine 8 and also performs appropriate injection according to the drive state of the engine 8 Fuel injection control is performed to open and close each injector 56 so as to achieve the timing and the injection amount. In principle, the controller 130 controls the injection pressure of fuel from each injector 56 so that the actual engine rotation speed detected by the engine rotation sensor 66 matches the preset idling rotation speed when the traveling vehicle 1 is stopped. The timing and injection amount (hereinafter referred to as target injection pattern) are feedback controlled. Other than the stop state, the controller 130 performs feedback control of the target injection pattern so that the actual engine rotational speed matches the reference rotational speed corresponding to the operation position of the throttle lever 29 (the detection result of the throttle potentiometer 68).

  In addition, the controller 130 changes the position of the upper spring seat 113 in conjunction with the change in the amount of chemical solution, and keeps the vehicle height of the traveling vehicle 1 constant regardless of the change in the amount of chemical solution, that is, the vehicle load (spring load). Carry out height adjustment control. The flowchart of FIG. 13 shows an example of the vehicle height adjustment control. An algorithm (program) shown in the flowchart of FIG. 13 is stored in the ROM of the controller 130 and is executed by the CPU after calling the algorithm into the RAM. The pair of electric motors 131 (a pair of electric cylinders 122) of the embodiment are configured to perform the same operation in synchronization with each other.

  In the vehicle height adjustment control, if both the pump switch 134 and the fan switch 135 are on (S01: YES), the power spray pump 9 and the fan switch 135 are driven to be in the chemical solution dispersion state. The detected value of 135 is read (S02), and the electric motor 131 is rotated in the forward and reverse directions according to the detected value of the chemical solution amount sensor 135 to extend and retract the electric cylinder 122, and the vehicle height of the traveling body 1 is a predetermined value (for example, The position of the upper spring seat 113 is changed along the expansion / contraction direction (vertical direction) of the compression spring 111 so as to be equal to the full height vehicle height (S03). Thereafter, the process returns to step S01.

  According to the above control, the position of the upper spring seat 113 can be changed in conjunction with the change in the amount of chemical solution, and the vehicle height of the traveling airframe 1 is kept constant regardless of the change in the amount of chemical solution, ie, the vehicle load (spring load). it can. For this reason, it is possible to suppress the possibility that the traveling airframe 1 comes in contact with the branches of trees at the time of agricultural work (chemical liquid dispersion work) in an orchard or the like.

  Note that, as shown in another example of FIG. 14, the vehicle height adjustment switch 137 is connected to the controller 130, and the electric motor 131 is rotated forward and reverse according to the operation amount (pressing time, operation position, etc.) of the vehicle height adjustment switch 137. The electric spring 122 may be rotated to extend and retract the electric cylinder 122 to change the position of the upper spring seat 113. In this case, by manually operating the vehicle height adjustment switch 137, the vehicle height of the traveling vehicle 1 can be adjusted as desired by the operator. Thereby, the vehicle height of the traveling airframe 1 (especially, the cabin 5) can be manually set to the minimum height at the time of agricultural work (chemical solution dispersion work) in an orchard or the like, and the risk of contact with branches or crops of trees can be suppressed. Also, the suspension device 110 described above may be applied to the rear axle case 14. The detector is not limited to the chemical solution amount sensor 136, and a weight sensor such as a load cell for detecting the weight of the chemical solution tank 6 may be employed.

  As apparent from the above description and FIGS. 10 and 11, the axle frame 13 constituting the traveling airframe 1, the axle case 13 supporting the left and right wheels 3, and the axle case 13 suspended on the airframe 2 In the agricultural work vehicle provided with the suspension device 110, the suspension device 110 includes a compression spring 111 and a damper 112 for attenuating the ground reaction force from the both wheels 3, and a spring seat 113 for abutting on one end side of the compression spring 111. And the spring seat body 113 is configured to be positionally changeable along the extension / contraction direction of the compression spring 111, so that the movement of the spring seat body 113 along the extension / contraction direction of the compression spring 111 The initial spring length of the compression spring 111 and hence the biasing force can be adjusted, and the vehicle height of the traveling body 1 can be adjusted in consideration of the vehicle body load (spring load). To become.

  Further, as is apparent from the above description and FIGS. 10 to 13, an actuator 122 for moving the spring seat body 113 along the expansion and contraction direction of the compression spring 111, and the amount of objects mounted on the traveling machine body 1 And a control device 130 for driving the actuator 122 based on the detection information of the detector 136. The spring seat 113 is positioned according to the amount of the mounted object mounted on the traveling body 1 Since it is changed, the position of the spring seat 113 is changed in conjunction with the change in the amount of the object to be mounted, and the vehicle of the traveling body 1 is changed regardless of the amount of the object to be mounted, ie, the load of the vehicle body (spring load). The height can be held constant.

  The present invention is not limited to the above embodiment, and can be embodied in various aspects. The configuration of the other components is not limited to the illustrated embodiment, and various modifications can be made without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 1 traveling body 3 front wheel 4 rear wheel 6 chemical solution tank 8 engine 101 front frame 102 beam frame 103 swing plate 109 portal frame 110 suspension device 111 coil spring 112 damper 113 upper spring seat 116 lower spring seat 118 rear arm 119 Front arm 122 Electric cylinder 130 Controller 131 Electric motor 132 Motor driver 136 Chemical amount sensor 137 Vehicle height adjustment switch

Claims (2)

An agricultural work vehicle comprising: an airframe frame constituting a traveling airframe; an axle case supporting left and right wheels; and a suspension device for suspending the axle case on the airframe frame.
The suspension system includes a compression spring and a damper for attenuating a ground reaction force from the wheels, a spring seat that abuts on one end of the compression spring, and the spring seat along an extension direction of the compression spring. It comprises an actuator to be moved, a detector for detecting an amount of a mounted object mounted on the traveling machine body, and a control device for driving the actuator based on detection information of the detector .
The spring seat is configured to be changeable in position along the expansion / contraction direction of the compression spring , and is changed in position in accordance with the amount of an object mounted on the traveling body.
Farm work vehicle. The traveling machine body is mounted with a chemical solution tank for storing a chemical solution, and the detector detects the amount of chemical solution in the chemical solution tank,
The agricultural work vehicle according to claim 1.

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