JP2018003904A - Working vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve a traveling feeling.SOLUTION: A working vehicle comprises working machine recognition means, a hydraulic clutch and a control device. The working machine recognition means recognizes a type of a working machine attached to a traveling vehicle body. The hydraulic clutch is arranged in a power transmission device for transmitting rotational power to drive wheels from an engine so as to be capable of adjusting connection pressure. The control device controls the connection pressure of the hydraulic clutch, stores a plurality of boosting patterns at the connection of the hydraulic clutch in advance, and selects the boosting pattern corresponding to the type of the working machine which is attached to the traveling vehicle body from a plurality of the boosting patterns on the basis of a recognition result of the working machine recognition means.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a work vehicle.

  2. Description of the Related Art Conventionally, work vehicles (for example, agricultural tractors) transmit rotational power output from an engine to a drive wheel by appropriately reducing the speed through a plurality of gears in a power transmission device and changing the combination of gears. Shift.

  In such a work vehicle, a clutch capable of adjusting the connection pressure is provided in the power transmission device, and for example, the clutch connection pressure (hereinafter referred to as “clutch pressure”) is temporarily increased after starting or shifting. Thus, a technique for suppressing a shock caused by a sudden change in the vehicle speed at the time of starting or shifting, so-called starting shock or shifting shock is known (for example, see Patent Document 1).

JP 2014-134291 A

  Here, in an agricultural tractor, for example, during high-load traveling such as tillage work by plow traction, the vehicle speed may change suddenly at the moment when the clutch pressure decreases. For this reason, even if the conventional techniques as described above are used, the start shock and the shift shock may not be suppressed depending on the work contents, and the start feeling and the shift feeling (hereinafter referred to as “running feeling” collectively). ") Sometimes worsened.

  The present invention has been made in view of the above, and an object of the present invention is to provide a work vehicle that can improve the traveling feeling.

  In order to solve the above-described problems and achieve the object, the work vehicle according to claim 1 is a work machine recognition means (600) for recognizing the type of the work machine (4) mounted on the traveling vehicle body (2). And a hydraulic clutch (62, 72, 124) provided in the power transmission device (5) for transmitting the rotational power from the engine (7) to the drive wheel (52) so that the connection pressure can be adjusted, and the hydraulic pressure The connection pressure of the clutch (62, 72, 124) is controlled, and a plurality of pressure increase patterns (Pa to Pc) when the hydraulic clutch (62, 72, 124) is connected is stored in advance, and the work implement recognition means ( 600) Control for selecting a boosting pattern (P) according to the type of the work implement (4) mounted on the traveling vehicle body (2) from the plurality of boosting patterns (Pa to Pc) based on the recognition result of 600). Equipped with device (3) And wherein the Rukoto.

  The work vehicle according to claim 2 is the work vehicle according to claim 1, further comprising an inclination sensor (2a) for detecting an inclination angle in the front-rear direction of the traveling vehicle body (2), and the control device (3). Is characterized in that one is selected from the plurality of boost patterns (Pa to Pc) based on the detection result of the tilt sensor (2a).

  A working vehicle according to claim 3 is a positioning device (317) that receives a positioning signal transmitted from a positioning satellite and measures the position of the traveling vehicle body (2) in the working vehicle according to claim 1 or 2. And determination means (321) for determining whether the traveling vehicle body (2) is on the road or in the field based on the measurement result of the positioning device (317), and the control device (3) includes: One of the plurality of boost patterns (Pa to Pc) is selected based on the determination result of the determination means (321).

  The work vehicle according to claim 4 is the work vehicle according to claim 3, further comprising work condition setting means (322) for setting a work condition for each field, wherein the control device (3) includes the work condition. One of the plurality of boost patterns (Pa to Pc) is selected based on the setting result of the setting means (322) and the measurement result of the positioning device (317).

  The work vehicle according to a fifth aspect is the work vehicle according to any one of the first to fourth aspects, wherein the hydraulic clutch (124) is a forward / reverse hydraulic clutch.

  A work vehicle according to a sixth aspect is the work vehicle according to any one of the first to fourth aspects, wherein the hydraulic clutch (62, 72) is a main transmission hydraulic clutch.

  According to the first aspect of the present invention, since an appropriate pressure increase pattern during traveling is selected according to the work implement attached to the traveling vehicle body, it is possible to suppress the start shock and the shift shock. Thereby, driving | running | working feeling can be improved.

  According to the second aspect of the present invention, in addition to the effect of the first aspect of the invention, the boosting pattern is automatically selected according to the front-rear direction inclination of the traveling vehicle body. In either case of the downward slope, a constant running feeling can be obtained.

  According to the invention described in claim 3, in addition to the effect of the invention described in claim 1 or 2, whether the traveling vehicle body is traveling on the road or on the field where the road surface condition is different, By being automatically selected, it is possible to obtain a good running feeling without requiring a special operation by the operator.

  According to the invention described in claim 4, in addition to the effect of the invention described in claim 3, since the pressure increasing pattern is automatically selected according to the field and the working conditions in the field, a special operation by the operator is performed. It is possible to obtain a good running feeling for each field without requiring any operation.

  According to the invention described in claim 5, in addition to the effect of the invention described in any one of claims 1 to 4, it is possible to suppress the start shock and improve the start feeling.

  According to the invention described in claim 6, in addition to the effect of the invention described in any one of claims 1 to 4, the shift shock can be suppressed and the shift feeling can be improved.

FIG. 1 is a schematic side view of a work vehicle (tractor). FIG. 2 is a functional block diagram of the tractor. FIG. 3 is a diagram showing a power transmission path of the tractor. FIG. 4 is a hydraulic circuit diagram of the tractor. FIG. 5A is an explanatory diagram (No. 1) of a boosting curve when a hydraulic clutch is connected. FIG. 5B is an explanatory diagram (part 2) of the boosting curve when the hydraulic clutch is connected. FIG. 5C is an explanatory diagram (part 3) of the boosting curve when the hydraulic clutch is connected. FIG. 6 is a flowchart illustrating another example of the processing procedure for changing the boosting pattern. FIG. 7A is an explanatory diagram illustrating an example of a map screen and an information screen. FIG. 7B is an explanatory diagram illustrating an example of a setting screen.

<Overall configuration of work vehicle>
Hereinafter, the present invention will be described in detail with reference to the drawings. In addition, this invention is not limited by the following embodiment. In addition, constituent elements in the following embodiments include those that can be easily assumed by those skilled in the art or that are substantially the same, that is, those in an equivalent range. Moreover, the component in the following embodiment can be combined suitably.

  A work vehicle according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic side view of a work vehicle (tractor) 1. FIG. 2 is a functional block diagram of the tractor 1. FIG. 3 is a diagram showing a power transmission path of the tractor 1. For easy understanding, the rear wheel 52 is seen through in FIG.

  In the following, for convenience of explanation, as shown in the figure, the three directions orthogonal to each other are respectively defined as the front-rear direction, the left-right direction, and the up-down direction, and the configuration of each part will be described according to this definition. The front-rear direction is the length direction of the tractor 1, the left-right direction is the width direction, and the up-down direction is the height direction. Among these, the front is the traveling direction of the tractor 1 during ground work, the left is the left-hand direction toward the front (front side of the paper in FIG. 1), and the right is the right-hand direction toward the front. The lower side is the direction in which gravity acts. In addition, these directions are defined for convenience in order to make the explanation easy to understand, and the present invention is not limited by these directions.

  A work vehicle, that is, a tractor 1 is an agricultural tractor that performs work on a farm field or the like. As shown in FIG. 1, a traveling vehicle body 2 having a front wheel 51 and a rear wheel 52, and a traveling control unit 3 (see FIG. 2). And corresponds to a “control device”). In the tractor 1, for example, the front wheel 51 is a steering wheel, and the rear wheel 52 is a driving wheel (driving wheel). The rear wheel 52 receives power generated by the engine 7 mounted in the hood 6 at the front of the traveling vehicle body 2 and a main transmission 40 (see FIG. 3) provided in the power transmission device 5 and the sub-wheel 52. The transmission device 140 (see FIG. 3) can be appropriately decelerated and transmitted. The rear wheel 52 is driven by the power transmitted from the engine 7.

  Further, in the tractor 1, the power generated by the engine 7 and decelerated by the main transmission 40 and the auxiliary transmission 140 can be transmitted to the front wheels 51 via the front wheel acceleration switching mechanism 172 (see FIG. 3). It has become. When the front wheel acceleration switching mechanism 172 transmits power, the front wheel 51 and the rear wheel 52 are driven by the power transmitted from the engine 7. When the front wheel acceleration switching mechanism 172 interrupts the transmission of power, the two wheels including only the rear wheel 52 are driven by the power transmitted from the engine 7. That is, the tractor 1 can be switched between two-wheel drive and four-wheel drive. A PTO (Power Take-Off) connecting device 8 to which the work machine 4 can be attached is disposed at the rear of the traveling vehicle body 2 of the tractor 1.

  Further, as shown in FIG. 1, a pilot seat 9 where a driver (also referred to as “worker”) sits when the tractor 1 is steered is provided at the center of the traveling vehicle body 2 of the tractor 1. A steering handle 10 used for steering the front wheels 51 is disposed in front of the vehicle. The steering handle 10 is disposed on the upper end side of a handle post 11 that rotatably supports the steering handle 10. A meter panel 31 and an operation panel 32 are provided in front of the handle post 11. Further, a pedal 9a (a clutch pedal, a brake pedal, an accelerator pedal, etc.) is installed on the lower side of the handle post 11, that is, in the vicinity of the driver's feet when the driver is sitting on the cockpit 9.

  In addition, a cylinder case 41 a is provided behind the traveling vehicle body 2. On both the left and right sides of the cylinder case 41a, lift arms 43a are provided so that the shaft center can turn around the axis AX1 in the left-right direction. When the working oil is supplied to the cylinder 41 in the cylinder case 41a, the lift arm 43a is turned up around the axis AX1, and when the working oil is discharged from the cylinder 41, the lift arm 43a is turned down around the axis AX1. A lift arm sensor 4c that detects the rotation angle of the lift arm 43a is provided at the base of the lift arm 43a. The height of the work implement 4 is calculated based on the detection value of the lift arm sensor 4c.

  The lift arm 43a and the lower link 42 are connected by a lift rod 43b. The lift rod 43b includes a double-acting horizontal control hydraulic cylinder, and the left and right sides of the work implement 4 are raised and lowered by expansion and contraction of the horizontal control hydraulic cylinder, and the length of the cylinder is increased by a stroke sensor (not shown). Detected. Further, an inclination sensor (traveling vehicle body tilt sensor) 2 a of the traveling vehicle body 2 is provided in the vicinity of the cockpit 9 of the tractor 1.

  The traveling vehicle body inclination sensor 2a detects at least the inclination angle of the traveling vehicle body 2 in the front-rear direction. The traveling control unit 3 (see FIG. 2) determines whether the traveling vehicle body 2 is in an upward inclination state or a downward inclination state based on the detection result (detected value) of the traveling vehicle body inclination sensor 2a, and the inclination Determining the degree (severity)

  In addition, it is good also as a structure which provides the inclination sensor (working machine inclination sensor) which detects the inclination-angle of the working machine 4 separately. By providing the work implement inclination sensor, the inclination control amount of the work implement 4 is calculated from a comparison between the detection value of the work implement inclination sensor and the detection value of the stroke sensor. The work implement lifting control unit 3b (see FIG. 2) drives the horizontal control hydraulic cylinder based on the calculated tilt control amount.

  In addition, the example shown in FIG. 1 is a case where the working machine 4 is a plow 4a. As shown in FIG. 1, a plow 4a is attached to the rear portion of the traveling vehicle body 2 of the tractor 1 via a three-point link mechanism (such as a lift arm 43a and a lift rod 43b). In the work implement lifting control unit 3b, the three-point link mechanism is moved up and down by the hydraulic cylinder 41, and the work implement 4 (plow 4a) is automatically activated according to the work load (traction load) detected by the draft sensor 4b. So-called draft control is performed, which makes it possible to perform stable work by moving up and down. Further, when lowering the plow 4a, the working machine elevating switch (not shown) disposed in the vicinity of the cockpit 9 is continuously pushed down to operate the cylinder 41 with the maximum amount of hydraulic oil, thereby drafting Control can be performed. If such an operation is performed, it is effective, for example, when the plow 4a is difficult to enter the soil at the time of plowing.

  In addition, a work machine connector 600 to which a cable on the work machine 4 side is connected is provided at the rear portion of the traveling vehicle body 2. The work machine connector 600 is, for example, AG-PORT (communication standard established by the Japan Agricultural Machinery Industry Association), and recognizes the type of the work machine 4 attached to the traveling vehicle body 2 as “work machine recognition”. It has a function as “means”.

  In addition, the work implement lifting control unit 3b changes the height of the work implement 4 by rotating the lift arm 43a based on a detection value of a tilling depth sensor (not shown) that detects the tilling depth, for example. Keep the tilling depth at the set value. Specifically, the work implement lifting control unit 3b moves the work implement 4 upward when the plowing depth is deeper than the set value, or moves the work implement 4 downward when the plowing depth is shallower than the set value. To do. Control by the work implement lifting control unit 3b that maintains the tilling depth at the set value in this way may be referred to as “depth control”.

  The tractor 1 performs so-called “decerer control” that reduces the descending speed of the work implement 4 near the ground so that no impact is generated when the work implement 4 is grounded, for example, when the work implement 4 is lowered. . In FIG. 1, the angular position around the axis AX1 of the lift arm 43a at which the work machine 4 starts to descend is the upper position UP, and an example of the angular position at which the work machine 4 performs ground work (cultivation) is the lower position LP. Show. Further, in FIG. 1, an angular position at which the lowering speed of the work implement 4 decreases at an angular position around the axis AX1 of the lift arm 43a is shown as a reference height DP (decerer position). When starting to descend from the upper position UP, the work machine 4 decreases the lowering speed at the reference height DP and lands at the lower position LP.

<Power transmission path>
Incidentally, the power of the engine 7 of the tractor 1 is transmitted to the rear wheels 52 via the main transmission 40, the forward / reverse hydraulic clutch 124 and the auxiliary transmission 140 in the power transmission device 5, as shown in FIG. The power of the engine 7 of the tractor 1 is also transmitted to the front wheels 51 via the main transmission 40, the forward / reverse hydraulic clutch 124, the auxiliary transmission 140, and the front wheel acceleration switching mechanism 172.

  3, the main transmission 40 includes a Hi-Lo transmission mechanism 60 and a main transmission mechanism 90, and the Hi-Lo transmission mechanism 60 further includes a first Hi-Lo transmission mechanism 61 and a second Hi-Lo transmission mechanism. The main transmission mechanism 90 includes a first main transmission mechanism 91 and a second main transmission mechanism 101.

  Among these, the 1st Hi-Lo speed change mechanism 61 has the 1st Hi-Lo speed change Lo side gear 63 and the 1st Hi-Lo speed change Hi side gear 64 from which the number of teeth differs. The gears 63 and 64 are a main transmission input shaft first gear 54 and a main transmission that are fixed to a main transmission input shaft 53 that is an input shaft when power output from the engine 7 is input to the main transmission 40. The gear is engaged with the device input shaft second gear 55. That is, the first Hi-Lo speed change Lo side gear 63 is engaged with the main transmission input shaft first gear 54, and the first Hi-Lo speed change Hi side gear 64 is engaged with the main transmission input shaft second gear 55.

  The first Hi-Lo speed change mechanism 61 includes a first Hi-Lo speed change hydraulic clutch 62 and a first Hi-Lo speed change output gear 65 that constitute a main speed change hydraulic clutch. The first Hi-Lo shift hydraulic clutch 62 includes a clutch for switching between the first Hi-Lo shift Lo side gear 63 and the first Hi-Lo shift output gear 65, the first Hi-Lo shift Hi side gear 64, and the first Hi-Lo. A clutch that switches between intermittent connection with the speed change output gear 65. For this reason, the first Hi-Lo shift hydraulic clutch 62 includes a first Hi-Lo shift Lo-side gear 63 and a first Hi-Lo shift Hi-side gear 64 and the first Hi-Lo shift output gear 65. In between, power transmission can be made possible. Further, the first Hi-Lo speed change output gear 65 is fixed to a main speed change mechanism first intermediate shaft 81 capable of transmitting power between the first Hi-Lo speed change mechanism 61 and the first main speed change mechanism 91. Engage with the intermediate shaft gear 82.

  Similarly, the second Hi-Lo speed change mechanism 71 has a second Hi-Lo speed change Lo side gear 73 and a second Hi-Lo speed change Hi side gear 74 with different number of teeth, and the second Hi-Lo speed change Lo side gear 73 is The main transmission input shaft first gear 54 meshes, and the second Hi-Lo shift Hi side gear 74 meshes with the main transmission input shaft second gear 55.

  The second Hi-Lo transmission mechanism 71 includes a second Hi-Lo transmission hydraulic clutch 72 and a second Hi-Lo transmission output gear 75 that constitute a main transmission hydraulic clutch. The second Hi-Lo speed change hydraulic clutch 72 includes a clutch for switching between the second Hi-Lo speed change Lo side gear 73 and the second Hi-Lo speed change output gear 75, the second Hi-Lo speed change Hi side gear 74, and the second Hi-Lo. And a clutch for switching between on and off of the speed change output gear 75. For this reason, the second Hi-Lo shift hydraulic clutch 72 is connected to one of the second Hi-Lo shift Lo side gear 73 and the second Hi-Lo shift Hi side gear 74 and the second Hi-Lo shift output gear 75. Power transmission between them can be made possible. Further, the second Hi-Lo speed change output gear 75 is fixed to a main speed change mechanism second intermediate shaft 85 capable of transmitting power between the second Hi-Lo speed change mechanism 71 and the second main speed change mechanism 101. The intermediate shaft gear 86 meshes with the intermediate shaft gear 86.

  Here, the second Hi-Lo shift output gear 75 has a different number of teeth from the first Hi-Lo shift output gear 65, and the second intermediate shaft gear 86 also has a different number of teeth from the first intermediate shaft gear 82. Therefore, the transmission ratio between the second Hi-Lo transmission output gear 75 and the second intermediate shaft gear 86 is different from the transmission ratio between the first Hi-Lo transmission output gear 65 and the first intermediate shaft gear 82. .

  The main transmission mechanism 90 has a main transmission mechanism output shaft first gear 111 and a main transmission mechanism output shaft second gear 112 fixed to a main transmission mechanism output shaft 110 that is an output shaft of the main transmission mechanism 90. The main transmission mechanism 91 includes a first main transmission first gear 93 that meshes with the main transmission mechanism output shaft first gear 111, and a first main transmission second gear 94 that meshes with the main transmission mechanism output shaft second gear 112. Have

  Further, the first main speed change mechanism 91 transmits the power transmitted from the main speed change mechanism first intermediate shaft 81 to one of the first main speed change first gear 93 and the first main speed change second gear 94. A first main transmission shifter 92 capable of transmission is provided. For this reason, the power transmitted from the main transmission mechanism first intermediate shaft 81 to the first main transmission mechanism 91 is transmitted through the first main transmission first gear 93 and the main transmission mechanism output shaft first gear 111, or The transmission can be transmitted to the main transmission mechanism output shaft 110 from any one of the transmission paths via the first main transmission second gear 94 and the main transmission mechanism output shaft second gear 112.

  Similarly, the second main transmission mechanism 101 includes a second main transmission first gear 103 that meshes with the main transmission mechanism output shaft first gear 111 and a second main transmission second gear that meshes with the main transmission mechanism output shaft second gear 112. 104 and a second main transmission shifter 102. For this reason, the power transmitted from the main transmission mechanism second intermediate shaft 85 to the second main transmission mechanism 101 is transmitted through the second main transmission first gear 103 and the main transmission mechanism output shaft first gear 111, or The transmission can be made to the main transmission mechanism output shaft 110 from any one of the transmission paths via the second main transmission second gear 104 and the main transmission mechanism output shaft second gear 112.

  Of the gears included in the main transmission mechanism 90, the first main transmission first gear 93 and the first main transmission second gear 94, the second main transmission first gear 103 and the second main transmission second gear 104, The transmission mechanism output shaft first gear 111 and the main transmission mechanism output shaft second gear 112 have different numbers of teeth. Therefore, the transmission ratio between the first main transmission first gear 93 and the main transmission mechanism output shaft first gear 111 and the first main transmission second gear 94 and the main transmission mechanism output shaft second gear 112 are between. It is different from the gear ratio.

  As described above, the main transmission 40 that can transmit the power input from the engine 7 side to the output side with different gear ratios by the first Hi-Lo transmission hydraulic clutch 62 and the first main transmission shifter 92 By switching the transmission path, the gear ratio is changed to provide an 8-speed gear stage. In other words, the main transmission 40 switches the input from the main transmission input shaft first gear 54 or the main transmission input shaft second gear 55 (second speed), the first intermediate shaft gear 82, or the second intermediate shaft. The output from the gear 86 can be switched (second speed), and the output from the main transmission mechanism output shaft first gear 111 or the main transmission mechanism output shaft second gear 112 can be switched (second speed). For this reason, the main transmission 40 has a gear stage of 2nd speed × 2nd speed × 2nd speed = 8th speed. The eighth gear is assigned from the first gear to the eighth gear from the gear stage having a large reduction ratio from the main transmission input shaft 53 to the main transmission mechanism output shaft 110 toward the gear stage having a small reduction ratio. .

  A main transmission mechanism output shaft 110 that is an output shaft of the main transmission 40 is connected to a forward / reverse input shaft 121 that is an input shaft of a forward / reverse switching mechanism 120 including a forward / reverse hydraulic clutch 124. A forward / reverse input first gear 122 and a forward / reverse input second gear 123 are fixed to the forward / reverse input shaft 121, and among these, the forward / reverse input second gear 123 is provided by the forward / reverse switching mechanism 120. The counter gear 134 fixed to the counter shaft 133 is engaged with the counter gear 134.

  The forward / reverse switching mechanism 120 has a forward / reverse output first gear 131 that meshes with the forward / reverse input first gear 122 and a forward / reverse output second gear 132 that meshes with the counter gear 134. Further, the forward / reverse switching mechanism 120 uses the power transmitted to the forward / reverse output first gear 131 or the forward / reverse output second gear 132 as either the forward / reverse output first gear 131 or the forward / reverse output second gear 132. From one side, it has a forward / reverse hydraulic clutch 124 that can transmit to a forward / reverse output shaft 130 that is an output shaft of the forward / reverse switching mechanism 120.

  The forward / reverse hydraulic clutch 124 is used for switching between forward and reverse movement of the rear wheel 52 by the power transmitted from the engine 7 and for transmitting and blocking the power transmitted from the engine 7 to the rear wheel 52. . The forward / reverse hydraulic clutch 124 includes a clutch that switches between the first and second output gears 131 and 130, and a clutch that switches between the second and second output gears 132 and 130. Thus, the gear connected to the forward / reverse output shaft 130 can be switched. The forward / reverse output first gear 131 side clutch and the forward / reverse output second gear 132 side clutch of the forward / reverse hydraulic clutch 124 operate by supplying hydraulic oil.

  Here, in the power transmission path from the forward / reverse input shaft 121 to the forward / reverse output shaft 130, the forward / reverse output first gear 131 directly meshes with the forward / reverse input first gear 122, whereas the forward / reverse output The second gear 132 meshes with the forward / reverse input second gear 123 via the counter gear 134. For this reason, in the forward / reverse output first gear 131 and the forward / reverse output second gear 132, the rotation directions are opposite to each other. Thus, when the power transmission path to the forward / reverse output shaft 130 is switched by the forward / reverse hydraulic clutch 124, the forward / reverse output first gear 131 side and the forward / reverse output second gear 132 side are switched. In the case of switching, the rotational directions of the power transmitted to the forward / reverse output shaft 130 are opposite to each other.

  When the forward / reverse switching lever is operated to the forward position, the forward / reverse hydraulic clutch 124 switches the power transmission path to the forward / reverse output shaft 130 to the forward / reverse output first gear 131 side, that is, the front side, and advances the rear wheel 52 forward. Rotate in the direction. When the forward / reverse switching lever is operated to the reverse position, the forward / backward hydraulic clutch 124 switches to the forward / reverse output second gear 132 side, that is, the rear side, and rotates the rear wheel 52 in the reverse direction. Further, the forward / reverse hydraulic clutch 124 cuts off transmission of power transmitted from the engine 7 to the rear wheel 52 when both clutches cut off transmission of power based on pedal operation of the clutch pedal, etc. The rear wheel 52 is restricted from rotating by the power from the engine 7.

  The forward / reverse output shaft 130 of the forward / reverse switching mechanism 120 is connected to a sub-transmission input shaft 141 that is an input shaft of the sub-transmission device 140, and the sub-transmission input shaft 141 has sub-transmission inputs having different numbers of teeth. The first gear 142 and the auxiliary transmission input second gear 143 are fixed.

  The sub-transmission device 140 includes a sub-transmission first gear 145 that meshes with the sub-transmission input first gear 142, and a sub-transmission second gear 146 that meshes with the sub-transmission input second gear 143. Further, the sub-transmission device 140 transmits the power transmitted to the sub-transmission first gear 145 and the sub-transmission second gear 146 from either the sub-transmission first gear 145 or the sub-transmission second gear 146. A sub-shift first shifter 144 that can be transmitted to a sub-shift output shaft 150 that is an output shaft of the device 140 is provided. Further, the sub-transmission device 140 transmits power transmitted to a gear having a different number of teeth between the front gear and the rear gear to any one of the gears having a different number of teeth between the front gear and the rear gear. On the other hand, a sub-transmission second shifter 171 that can be transmitted to the sub-transmission output shaft 150 that is the output shaft of the sub-transmission device 140 is provided.

  Here, the transmission ratio between the auxiliary transmission input first gear 142 and the auxiliary transmission first gear 145 and the transmission ratio between the auxiliary transmission input second gear 143 and the auxiliary transmission second gear 146 are different from each other. Therefore, when the transmission path of power to the auxiliary transmission output shaft 150 is switched between the auxiliary transmission first gear 145 side and the auxiliary transmission second gear 146 side by the auxiliary transmission first shifter 144, the auxiliary transmission input shaft The transmission gear ratio between 141 and the auxiliary transmission output shaft 150 changes. In addition, when the auxiliary transmission second shifter 171 is used to switch between the front gear and the rear gear, the transmission ratio between the auxiliary transmission input shaft 141 and the auxiliary transmission output shaft 150 changes. As described above, the sub-transmission device 140 has four-speed gear stages having different gear ratios and can be switched.

  An auxiliary transmission output gear 151 is fixed to the auxiliary transmission output shaft 150, and the auxiliary transmission output gear 151 meshes with a rear wheel differential 155 that is a differential gear for the rear wheel 52. The rear wheel differential 155 is configured to be able to transmit power to a rear wheel drive shaft 156 connected to the rear wheel 52, whereby the power output from the auxiliary transmission 140 is transmitted to the rear wheel 52. Can be transmitted.

  As shown in FIG. 3, the tractor 1 includes a PTO output mechanism 160 that transmits power generated by the engine 7 to the PTO shaft 8 a of the PTO coupling device 8. The PTO output mechanism 160 can receive power from the main transmission input shaft second gear 55 of the main transmission input shaft 53, and switches between transmission and interruption of power to the PTO shaft 8a side. It has a clutch 161 and a PTO transmission 162 that shifts when power is transmitted to the PTO shaft 8a.

  Further, as shown in FIG. 3, the tractor 1 includes a front wheel side power transmission mechanism 170 including a front wheel acceleration switching mechanism 172 that transmits power generated by the engine 7 to the front wheel 51 side. The front wheel side power transmission mechanism 170 is capable of receiving power from the auxiliary transmission device 140 and performs switching of the rotational speed when transmitting the power received from the auxiliary transmission device 140 to the front wheel 51 side. A front wheel acceleration switching mechanism 172 that switches between transmission and interruption of power to the front wheel 51 is provided.

  The front wheel acceleration switching mechanism 172 is neutral when the two wheels are driven, that is, when the power to the front wheels 51 is cut off. The front wheel acceleration switching mechanism 172 connects the rear clutch when driving four wheels, that is, when transmitting power to the front wheel 51, and connects the front clutch when increasing the front wheel speed.

  Further, the front wheel side power transmission mechanism 170 has a rotational speed and a rotation direction (according to the rotation of the rear wheel 52) of the rear wheel side power transmission gear 173 disposed on the rear output side of the front wheel acceleration switching mechanism 172. A vehicle speed sensor 211 for detecting information) is provided. The vehicle speed sensor 211 detects the rotation speed and the rotation direction of the rear wheel side power transmission gear 173 as an output shaft portion output from the front wheel speed increase switching mechanism 172 of the front wheel side power transmission mechanism 170, thereby Information corresponding to rotation is detected. In the present embodiment, the vehicle speed sensor 211 may be arranged anywhere as long as it can detect information according to the rotation of the rear wheel 52, and may detect the rotation speed and rotation direction of any member.

  The front wheel side power transmission gear 180 disposed on the output side of the front wheel side power transmission mechanism 170 meshes with a front wheel differential 181 that is a differential gear for the front wheel 51, and the front wheel differential 181 is connected to the front wheel 51. Power is transmitted to the front wheel drive shaft 183 through a vertical shaft 182 and the like. As a result, the power output from the front wheel side power transmission mechanism 170 can be transmitted to the front wheel 51.

<Control device>
As shown in FIG. 2, the travel control unit 3 constituting the control device of the tractor 1 includes an engine control unit 3 a that controls the engine 7, etc. The unit 3b, the meter panel 31, the operation panel 32, and the like are connected to be able to communicate with each other via the communication unit 318. The communication unit 318 is a communication line such as a CAN (Controller Area Network).

  The tractor 1 also includes a positioning device 317 that receives a positioning signal transmitted from a positioning satellite and measures the position of the traveling vehicle body 2. Specifically, the tractor 1 is provided with a GPS control device (317) as a positioning device that acquires current position information of the traveling vehicle body 2 by GPS (Global Positioning System). A position on the ground can be measured by acquiring GPS coordinates at predetermined time intervals via a GPS antenna (see FIG. 1) provided above the traveling vehicle body 2.

  Note that the above CAN includes not only wired communication but also wireless communication. In addition, the communication unit 318 is provided so as to be able to communicate with a mobile terminal MT such as a tablet PC or a smartphone. Note that the mobile terminal MT may have a built-in GPS (MTa).

  In addition, the mobile terminal MT includes a determination unit 321 as a determination unit that determines whether the traveling vehicle body 2 is on the road or in the field based on the measurement result of the GPS control device 317. In addition, the mobile terminal MT includes a setting unit 322 as a work condition setting unit that allows an operator to set work conditions for each field (such as work contents in each field and field conditions such as soil quality in each field). The determination unit 321 and the work condition setting unit 322 will be described later with reference to FIGS. 7A and 7B.

  As shown in FIG. 2, the engine control unit 3a is based on the engine exhaust temperature, the engine speed, the pressure of the engine lubricating oil, the temperature of the cooling water of the engine 7, the fuel supply pressure, the accelerator operation amount, and the like. Thus, a signal for operating the injector that injects into the cylinder of the engine 7 is output.

  To the work implement lifting / lowering control unit 3b, signals of various sensors such as the position control sensor 4b and the lift arm sensor 4c, a raising position restriction signal of the raising position restriction dial 312 and a lowering speed setting signal of the lowering speed adjustment dial 313 are input. The The work implement raising / lowering control unit 3b outputs a work implement raising / lowering signal to the work implement raising solenoid 314 and the work implement lowering solenoid 315 to operate the cylinder 41.

  The traveling control unit 3 controls the traveling of the tractor 1 (the traveling vehicle body 2) by controlling the main transmission 40, the auxiliary transmission 140, the forward / reverse switching mechanism 120, the PTO output mechanism 160, and the front wheel side power transmission mechanism 170. . For example, when the brake depression detection switch 25 detects the pedal operation of the brake pedal 9a by the operator and the vehicle speed sensor 211 detects the rotation of the auxiliary transmission input first gear 142 (see FIG. 3), The hydraulic pressure to the front or rear clutch of the forward / reverse hydraulic clutch 124 (see FIG. 3) is controlled so that the traveling vehicle body 2 is stopped or substantially stopped.

  The travel control unit 3 receives the travel speed of the travel vehicle body 2 from the vehicle speed sensor 211, the temperature of the mission oil, the detection result of the brake depression detection switch 25, and the like from the oil temperature sensor 320. Further, the traveling control unit 3 receives the detection result of the forward clutch pressure sensor 230a that detects the hydraulic pressure of the clutch on the forward / reverse output first gear 131 (see FIG. 3) side of the forward / reverse hydraulic clutch 124, and the forward / reverse hydraulic pressure is detected. A reverse clutch pressure sensor for controlling the hydraulic pressure of the clutch on the side of the forward / reverse output second gear 132 (see FIG. 3) in the clutch 124 is connected and outputs such a control signal.

  Further, the traveling control unit 3 includes information indicating ON / OFF from the clutch automatic cutoff setting switch 28, a detection result from the main shift lever position sensor 210 that detects an operation position of the main shift lever, and an operation position of the sub shift lever. The detection result from the sub-shift position sensor 231 for detecting the forward shift, the detection result from the forward / reverse lever position sensor 27 for detecting the operation position of the forward / reverse switching lever, the sensitivity setting value at the time of shift set by the shift sensitivity dial 323, etc. Entered.

  Further, the traveling control unit 3 operates the forward / reverse output first gear 131 (both see FIG. 3) in the forward / reverse hydraulic clutch 124, and the forward / reverse output second gear 132 (FIG. 3). Connected to a reverse switching solenoid 262 for operating the clutch on the reference side, and a forward / reverse boosting solenoid 265 for controlling the hydraulic pressure when the forward / reverse hydraulic clutch 124 is operated in order to reduce a shock (starting shock) at the time of starting forward or reverse. Then, these control signals are output.

  Further, the traveling control unit 3 operates the first main transmission shifter 92 on the side where the main transmission mechanism first intermediate shaft 81 and the first main transmission first gear 93 (both see FIG. 3) are connected. A first main transmission first solenoid 251, a first main transmission second solenoid 252 that is actuated on the side where the main transmission mechanism first intermediate shaft 81 and the first main transmission second gear 94 (both see FIG. 3) are connected. Connected to output these control signals. Further, the traveling control unit 3 operates the second main transmission shifter 102 on the side where the main transmission mechanism second intermediate shaft 85 and the second main transmission first gear 103 (both see FIG. 3) are connected. The second main transmission first solenoid 255, the second main transmission second solenoid 256 that is operated to the side where the main transmission mechanism second intermediate shaft 85 and the second main transmission second gear 104 (see FIG. 3) are connected. Connected to output these control signals.

  In addition, the travel control unit 3 is configured to operate the first Hi-Lo speed change Lo side gear 63 (see FIG. 3) side clutch, the first Lo side solenoid 242, and the first Hi-Lo speed change hydraulic clutch 62 in the first Hi-Lo speed change Hi side. A first Hi-side solenoid 241 for operating the clutch on the gear 64 (see FIG. 3) side is connected to output these control signals. Further, the traveling control unit 3 operates the second Hi-Lo shift hydraulic clutch 72 and the second Hi-Lo shift hydraulic clutch 72 to operate the second Hi-Lo shift Lo side gear 73 (both see FIG. 3) side clutch. A second Hi-side solenoid 245 that operates the clutch on the side of the transmission Hi-side gear 74 (both see FIG. 3) is connected to output these control signals.

  The traveling control unit 3 is connected to a 4WD solenoid 325 for operating the front wheel acceleration switching mechanism 172 (see FIG. 3), a front wheel acceleration solenoid 326, and a PTO clutch solenoid 328 for operating the PTO clutch 161 (see FIG. 3). These control signals are output.

  When controlling the tractor 1, for example, the traveling control unit 3 reads the computer program into a memory incorporated in the processing unit based on the detection result of the main shift lever position sensor 210 or the like. The travel control of the tractor 1 is performed by controlling the actuators such as the first Hi-side solenoid 241 according to the result of the calculation. In this case, the processing unit appropriately stores a numerical value in the middle of the calculation in the storage unit, extracts the stored numerical value, and executes the calculation.

<Hydraulic circuit for traveling vehicle body>
Next, the hydraulic circuit of the tractor 1 will be described with reference to FIG. FIG. 4 is a hydraulic circuit diagram of the tractor 1. The tractor 1 has a hydraulic circuit HCA and a hydraulic circuit HCB. The hydraulic circuit HCA and the hydraulic circuit HCB are hydraulically supplied by using the lubricating oil as a tank port T in the transmission case of the power transmission device 5 (see FIG. 1) by the pump PM driven by the engine 7.

  As shown in FIG. 4, the hydraulic fluid HCA is supplied with pressure oil sent from the pump PM. The hydraulic circuit HCA includes a first main transmission valve 190, a second main transmission valve 191, and a reverser valve 192. The first main transmission valve 190 switches the first Hi-Lo transmission hydraulic clutch 62 and the first main transmission shifter 92. The second main transmission valve 191 switches the second Hi-Lo transmission hydraulic clutch 72 and the second main transmission shifter 102. The reverser valve 192 switches the forward / reverse hydraulic clutch 124. The first main transmission valve 190 and the second main transmission valve 191 are proportional pressure control valves. Proportional solenoids 190a, 190b, 191a, 191b are used for the first main transmission valve 190 and the second main transmission valve 191, respectively, and the proportional solenoids 190a, 190b, 191a, 191b are electrically controlled. Thus, by using the proportional solenoids 190a, 190b, 191a, 191b for the first main transmission valve 190 and the second main transmission valve 191, the first Hi-Lo transmission hydraulic clutch 62 and the first Hi-Lo transmission hydraulic clutch 72 are connected. Boost control can be performed.

<Hydraulic circuit for raising and lowering work equipment>
As shown in FIG. 4, a cylinder 41 is connected to the hydraulic circuit HCB. By changing the flow of oil in the hydraulic circuit HCB, the cylinder 41 expands and contracts to raise and lower the work implement 4. That is, the hydraulic circuit HCB and the cylinder 41 are elevating parts that elevate the work implement 4 relative to the traveling vehicle body 2. As shown in FIG. 4, the hydraulic circuit HCB includes a work implement ascending solenoid 314, a work implement descending solenoid 315, a descending pilot valve 413, a descending main valve 414, an ascending main valve 415, an ascending pilot valve 417, And a check valve 418.

  Pressure oil sent out from the pump PM is supplied to the hydraulic circuit HCB via a pressure reducing circuit, a filter, or the like. The work implement lifting / lowering control unit 3b switches the lowering main valve 414 and the rising main valve 415 by outputting a work implement raising / lowering signal to the work implement raising solenoid 314 and the work implement lowering solenoid 315.

  For example, when the lift pilot valve 417 is switched from the oil chamber 417a having a check valve to the oil chamber 417b having a throttle by the work implement lift solenoid 314, the lift main valve 415 is opened. Thereby, the pressure oil from the pump PM is supplied to the cylinder 41 (see FIG. 1) side, the cylinder 41 is extended, and the work machine 4 is raised. When the rising main valve 415 returns to the state shown in FIG. 4, the pressure oil sent to the cylinder 41 is restricted from flowing out to the hydraulic circuit HCB side by the check valve 418, and the position of the lift arm 43 a is maintained. Is done.

  When the lowering pilot valve 413 is switched from the oil chamber 413a having the check valve to the oil chamber 413b having the throttle by the work implement lowering solenoid 315, the lowering main valve 414 is opened. Thereby, the oil pushed out from the cylinder 41 by the dead weight of the work machine 4 is discharged to the tank port T, the cylinder 41 is contracted, and the work machine 4 is lowered.

  The work implement lowering solenoid 315 is a proportional solenoid, and the lowering pilot valve 413 can change the flow rate of oil passing through the lowering pilot valve 413 by adjusting the throttle of the oil chamber 413b with the proportional solenoid. it can. Further, the lowering speed of the work machine 4 changes according to the flow rate of the oil passing through the lowering pilot valve 413. For example, if the throttle opening of the oil chamber 413b is increased, the flow rate of oil passing through the descending pilot valve 413 per unit time increases, and the descending speed of the work implement 4 increases. On the other hand, if the throttle opening of the oil chamber 413b is reduced, the flow rate of the oil passing through the descending pilot valve 413 per unit time decreases, and the descending speed of the work implement 4 increases.

  Thus, the work implement lifting control unit 3b (see FIG. 2) can arbitrarily change the opening degree of the lowering pilot valve 413 by the work implement lowering solenoid 315 that is a proportional solenoid. Therefore, the lowering speed of the work machine 4 can be arbitrarily changed.

  As shown in FIG. 4, a return valve 419 is provided between the hydraulic circuit HCB and the cylinder 41. The return valve 419 has a throttle that can be manually changed in opening degree, and adjusts the return amount of oil from the cylinder 41 to the tank port T per unit time by the operator setting the throttle amount. Is possible. Therefore, the return valve 419 can also arbitrarily change the lowering speed of the work implement 4 and can improve the convenience for the operator.

  Here, in the tractor 1, the connection pressure (clutch pressure) of the forward / reverse hydraulic clutch 124 and the main transmission hydraulic clutches 62 and 72 is temporarily lowered at the time of starting or shifting so that a predetermined pressure increase curve (see FIG. 5A) is obtained. The start-up shock and the speed change shock are suppressed by gradually increasing the pressure. The boost control is performed by the travel control unit 3.

  However, for example, when shifting the traveling vehicle body 2 at the time of high load traveling such as tillage work by plow towing using the plow 4a for the work machine 4, the vehicle speed suddenly increases at the moment when the clutch pressure of the main transmission hydraulic clutches 62, 72 decreases. May fall. For this reason, the start shock and the shift shock may not be suppressed depending on the work content and the field conditions that require high-load travel, and the travel feeling such as the start feeling and the shift feeling may deteriorate. Therefore, the tractor 1 suppresses the start shock and the shift shock by automatically selecting an appropriate boosting curve according to the work content (the type of the work implement 4 attached to the traveling vehicle body 2) and the field conditions. It was decided to suppress the deterioration of the driving feeling.

<How to change the boost pattern>
Next, with reference to FIG. 5A, FIG. 5B, and FIG. 5C, the boosting curve when the hydraulic clutch (the forward / reverse hydraulic clutch 124, the main transmission hydraulic clutch 62, 72) of the tractor 1 is connected will be described. FIG. 5A to FIG. 5C are explanatory diagrams of a boosting curve when the hydraulic clutches 124, 62, 72 are connected. 5A to 5C show the pressure increase curves of the forward / reverse hydraulic clutch 124 and the main transmission hydraulic clutches 62 and 72 as hydraulic clutches, and the vertical axis indicates the clutch pressure [kgf / cm of the hydraulic clutches 124, 62, 72. ² ], and the horizontal axis represents time [t] (for example, [msec]).

  In FIGS. 5A to 5C, FIG. 5A shows a normally set boost curve, FIG. 5B shows a high load set boost curve, and FIG. 5C shows a low load set boost curve. That is, FIGS. 5A to 5C show three preset pressure increase patterns P (Pa to Pc) at the time of a similar start or shift operation.

  FIG. 5A shows a boosting curve (boosting pattern Pa) when the traveling vehicle body 2 smoothly starts or shifts on a flat road surface, for example. Note that the boosting curve as shown in FIG. 5A is basically set at the time of shipment. Such a boosting curve is a standard boosting curve during normal load traveling. In the case of starting, it is a standard boosting curve when the forward / reverse lever is at the same shift position. The boosting curve may be stored in the control device (running control unit 3) as one of a plurality of boosting patterns P. As shown in FIG. 5A, when starting or shifting with the hydraulic clutches 124, 62, 72, the traveling control unit 3 (see FIG. 2) generates a starting instruction or a shifting instruction by operating the forward / reverse lever, the main shifting lever, or the like. Thereafter, control is performed to increase the clutch pressure with a specified pressure increase curve after the hydraulic oil filling time has elapsed.

  Here, the predetermined time after the hydraulic oil filling time elapses can be adjusted, and the clutch pressure is temporarily lowered during the predetermined time and then gradually increased. When the hydraulic clutches 124, 62, 72 are connected, the clutch pressure is controlled so as to obtain a boosting curve as shown in FIG. 5A, thereby suppressing start shocks and shift shocks at the time of starting and shifting in the traveling vehicle body 2. Can do.

  FIG. 5B shows a boosting curve (boosting pattern Pb) when a high load such as a tilling work by the plow 4a (see FIG. 1) is assumed, for example. As shown in FIG. 5B, in starting and shifting under high load conditions, as shown by the broken lines in the figure, the increase in clutch pressure tends to be delayed when the hydraulic clutches 124, 62, 72 are connected. For this reason, it is preferable that the pressure increase curve has a high clutch pressure under high load conditions.

  FIG. 5C shows a boosting curve (boosting pattern Pc) when a low load is assumed such that the traveling vehicle body 2 travels on a downhill (downhill inclined surface), for example. As shown in FIG. 5C, when starting or shifting under a low load condition, the clutch pressure tends to increase quickly when the hydraulic clutches 124, 62, 72 are connected, as indicated by the broken lines in the figure. For this reason, it is preferable that the pressure increase curve has a low clutch pressure under low load conditions.

  In the traveling control unit 3, the boost pattern P (Pa to Pc) as described above is determined according to various conditions such as the type of the work implement 4 recognized by the work implement connector 600 serving as the work implement recognition means. By selecting the optimum one, it is possible to automatically engage the clutch with the optimum boosting curve. One boost pattern P selected from a plurality of boost patterns P (Pa to Pc) is preset as table data for each type of work implement 4.

  According to such a configuration, an appropriate boosting pattern P during traveling is selected according to the work implement 4 attached to the traveling vehicle body 2, so that a start shock and a shift shock can be suppressed. Thereby, driving | running | working feeling can be improved. In addition, since the appropriate boost pattern P is automatically selected, the operator does not need to adjust himself / herself, the burden on the operator is reduced, and convenience is improved. Moreover, even when the operator forgets to change the sensitivity, it is possible to prevent the start shock and the shift shock from occurring.

  In addition to the type of work implement 4, the above conditions may be configured to select the boost pattern P based on the detection result of the inclination sensor (traveling vehicle body inclination sensor) 2 a. According to such a configuration, since the boosting pattern P is automatically selected according to the front-rear direction inclination of the traveling vehicle body 2, a constant traveling fee is maintained regardless of whether the traveling vehicle body 2 is on the upward inclined surface or the downward inclined surface. It can be a ring. Specifically, the boosting pattern P suitable for each of the case where the traveling vehicle body 2 is traveling on an upward inclined surface and the case where the traveling vehicle body 2 is traveling on an inclined downward surface is selected. Ring, speed change feeling) can be stabilized. Moreover, since the pressure | voltage rise pattern P according to the degree of inclination is selected, it can be set as a favorable driving | running | working feeling (start feeling, shift feeling).

  Note that a switch that switches between enabling and disabling of the boosting pattern P automatic selection function at the time of starting or shifting may be provided near the cockpit 9 or the like. Since some operators may want to disable the automatic selection function, providing such a switch can improve versatility.

<Another example of the method for changing the boosting pattern>
Next, a processing procedure according to another example of the method for changing the boosting pattern P (Pa to Pc) executed by the tractor 1 will be described with reference to FIG. FIG. 6 is a flowchart showing another example of the processing procedure for changing the boost pattern P (Pa to Pc). In the example shown in FIG. 6, a boost pattern A (see FIG. 5A) that is a standard boost curve is also positioned as one of a plurality of boost patterns P that are selected by the travel control unit 3.

  When a suitable pressure increase pattern P of the clutch pressure in the forward / reverse hydraulic clutch 124 or the main transmission hydraulic clutch 62, 72 (both see FIG. 3) is selected, when the forward / reverse lever or the main transmission lever is operated, FIG. As shown in FIG. 4, various conditions are read in the travel control unit 3 (step S101). As described above, the various conditions include the type of the work implement 4 recognized by the work implement recognition means (work implement connector) 600, the detection result of the inclination sensor (traveling vehicle body inclination sensor) 2a, and the like.

  When a normal load is assumed based on the conditions read in step S101 (step S102, Yes), the travel control unit 3 selects the boost pattern Pa (see FIG. 5A) (step S103), and the hydraulic clutch 124, The clutch pressure at the time of connecting 62 and 72 is changed (step S104). That is, the clutch pressure remains a standard pressure increase curve.

  Further, when a high load is assumed in step S102 other than the normal load (No in step S102) (step S105, Yes), the travel control unit 3 selects the boost pattern Pb (see FIG. 5B) (step S106). Then, the clutch pressure when the hydraulic clutches 124, 62, 72 are connected is changed (step S104).

  In step S105, when a load other than a high load (step S105, No), that is, a low load is assumed, the travel control unit 3 selects the boost pattern Pc (see FIG. 5C) (step S107), and the hydraulic clutch 124, The clutch pressure at the time of connecting 62 and 72 is changed (step S104).

  Next, an example in which the boost pattern P is changed based on conditions other than the above will be described with reference to FIGS. 7A and 7B. FIG. 7A is an explanatory diagram illustrating an example of a map screen and an information screen displayed on the mobile terminal MT. FIG. 7B is an explanatory diagram illustrating an example of a setting screen for the boost pattern P.

  In the traveling control unit 3, whether or not the traveling vehicle body 2 is traveling on the road based on the measurement result of the GPS control device 317 that is a positioning device by the determination unit (determination unit) 321 provided in the mobile terminal MT, or the field If it is determined whether the vehicle is traveling, a suitable boosting pattern P set in advance may be selected based on the determination result. Further, in the travel control unit 3, a suitable boosting voltage set in advance by the work condition setting means (setting unit) 322 provided in the mobile terminal MT is set based on the setting result of the setting unit 322 and the measurement result of the GPS control device 317. The pattern P may be selected. In the example of changing the boosting pattern P, the screen of the mobile terminal MT is displayed as a map screen as shown in FIG. 7A (left half), and as shown in FIG. 7A (right half). Display detailed information.

  When the mobile terminal MT receives the GPS signal and recognizes that the traveling vehicle body 2 has entered each field (for example, the fields A to C shown in FIG. 7A), the mobile terminal MT displays the setting screen as shown in FIG. 7B. The boosting curve may be set based on the determined criteria.

  According to such a configuration, regardless of whether the traveling vehicle body 2 is traveling on the road or on the field where the road surface condition is different, the boosting pattern P is automatically selected, so that no special operation by the operator is required. The driving feeling can be improved. Moreover, since the pressure | voltage rise pattern P is automatically selected according to the field and the working condition in this field, it is favorable driving | running | working for every field (for example, field AC), without requiring special operation by an operator. It can be a feeling.

  Further effects and modifications can be easily derived by those skilled in the art. Thus, the broader aspects of the present invention are not limited to the specific details and representative embodiments shown and described above. Accordingly, various modifications can be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents.

1 Tractor (work vehicle)
2 Traveling vehicle body 2a Traveling vehicle body tilt sensor (tilt sensor)
3 Travel controller (control device)
3a Engine control unit 3b Work implement lifting control unit 4 Work implement 4a Plow 4c Lift arm sensor 5 Power transmission device 7 Engine 8 PTO coupling device 8a PTO shaft 9 Pilot seat 40 Main transmission 41 Cylinder 41a Cylinder case 42 Lower link 43a Lift arm 43b Lift rod 51 Front wheel 52 Rear wheel (drive wheel)
62 1st Hi-Lo shifting hydraulic clutch (main shifting hydraulic clutch)
72 2nd Hi-Lo shifting hydraulic clutch (main shifting hydraulic clutch)
124 Forward / backward hydraulic clutch 317 GPS control device (positioning device)
318 Communication unit 321 determination unit (determination unit)
322 setting unit (working condition setting means)
600 Work machine connector: AG-PORT (work machine recognition means)
HCA Hydraulic circuit HCB Hydraulic circuit MT Mobile terminal

Claims (6)

A work machine recognition means for recognizing the type of work machine mounted on the traveling vehicle body;
A hydraulic clutch provided in the power transmission device for transmitting the rotational power from the engine to the drive wheels so that the connection pressure can be adjusted;
The connection pressure of the hydraulic clutch is controlled, and a plurality of pressure increase patterns at the time of connection of the hydraulic clutch are stored in advance, and the plurality of pressure increase patterns are attached to the traveling vehicle body based on the recognition result of the work implement recognition means. A work vehicle comprising: a control device that selects a boosting pattern according to a type of the working machine. An inclination sensor that detects an inclination angle of the traveling vehicle body in the front-rear direction;
The controller is
The work vehicle according to claim 1, wherein one of the plurality of boosting patterns is selected based on a detection result of the tilt sensor. A positioning device that receives a positioning signal transmitted from a positioning satellite and measures the position of the traveling vehicle body;
Determination means for determining whether the traveling vehicle body is on the road or in the field based on the measurement result of the positioning device; and
The controller is
The work vehicle according to claim 1 or 2, wherein one of the plurality of boosting patterns is selected based on a determination result of the determination unit. A work condition setting means for setting the work condition for each field;
The controller is
The work vehicle according to claim 3, wherein one of the plurality of boosting patterns is selected based on a setting result of the work condition setting means and a measurement result of the positioning device. The work vehicle according to any one of claims 1 to 4, wherein the hydraulic clutch is a forward / reverse hydraulic clutch. The work vehicle according to any one of claims 1 to 4, wherein the hydraulic clutch is a main transmission hydraulic clutch.

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