JP2021181806A - Work vehicle - Google Patents

Abstract

To provide a work vehicle which can easily grasp a vehicle speed which a driver wishes to store at the time of travelling, and which can continue the travel at the vehicle speed and reproduce the travel at that travel speed with a simple operation.SOLUTION: A work vehicle includes a control device 100 which has: a first function which controls in such a manner that, when a vehicle speed memory button 28 is depressed for a long time equal to or longer than predetermined time during a travel of operating accelerator operation tools 15, 16 and shift operation tools 23, 18, the rotational frequency of the engine and the rotation angle of a trunnion shaft 47 at that time are stored, and travel is performed by maintaining the stored rotation frequency of the engine and the rotation angle of the trunnion shaft 47; and a second function which controls in such a manner that, when the vehicle speed memory button 28 is depressed for a short time below the predetermined time during a travel operating the accelerator operation tools 15, 16 and the shift operation tools 23, 18, travel is performed by maintaining the stored rotational frequency of the engine and the rotation angle of the trunnion shaft 47.SELECTED DRAWING: Figure 6

Description

The present invention relates to a work vehicle such as a tractor.

Conventionally, as a work vehicle such as a tractor, a work vehicle provided with an speed increase switch or a deceleration switch for speeding up or decelerating during constant speed running, in addition to an auto-cruise running operation means for keeping the running speed constant. Is known (Patent Document 1).

This conventional work vehicle has a trunnion shaft rotation mechanism that maintains the rotation angle of the trunnion shaft in the hydrostatic transmission according to the amount of depression of the accelerator pedal when the operating means for auto-cruise driving is operated. The auto-cruise function that controls and keeps the traveling speed constant, and the trunnion shaft rotation mechanism is controlled when the speed increase switch or deceleration switch is short-pressed within a predetermined time during the auto-cruise function. It is provided with a control device having a temporary speed-increasing / decelerating function for temporarily increasing or decelerating the traveling speed of the vehicle for the predetermined time.

Further, this conventional work vehicle is provided with a memory switch in which the following operations are performed. When this memory switch is long-pressed for a predetermined time or longer, the current accelerator pedal depression amount is memorized, and when a short-press operation is performed within a predetermined time, the memorized depression amount is memorized. The running according to is executed. Further, this memory switch is designed so that the memory switch is turned on when a short press operation is performed.

Japanese Unexamined Patent Publication No. 2016-8665

In the above-mentioned conventional work vehicle, if you want to temporarily change the speed even during constant speed running by the auto cruise function, if you press the speed increase switch or deceleration switch for a predetermined time, only the time when the switch is pressed , The traveling speed at that time can be temporarily increased or decreased.

On the other hand, in the conventional work vehicle, when the speed at the time of constant speed running by the above auto cruise function is temporarily changed, the running speed at the time of starting the last auto cruise function is temporarily stored. It may be unclear to the driver when the speed during constant speed driving was the memorized speed, and what was the speed when speeding up or decelerating. Sometimes it became unclear and it was not possible to reproduce the speed.

Further, in a conventional work vehicle, when the memory switch is pressed and held for a long time, the amount of depression of the accelerator pedal at that time is only memorized, and in order to travel with the memorized amount of depression, the long press operation is performed. It was necessary to short-press the memory switch after memorizing it, and the amount of depression was sometimes unknown.

The subject of the present invention is that it is easy for the driver to grasp the vehicle speed that he / she wants to memorize when driving, and it is possible to realize the continuation of traveling at that vehicle speed and the reproduction of traveling at that vehicle speed by a simple operation. To provide a work vehicle.

The above-mentioned problems of the present invention are solved by the following means.

That is, the invention according to claim 1 is
Engine (3) and
Accelerator operating tools (15, 16) that adjust the engine speed according to the amount of operation,
An engine rotation speed sensor (72) that detects the rotation speed of the engine (3), and
It has a trunnion shaft (47) that rotates to adjust the tilt angle of the swash plate (45), and is a hydrostatic type non-hydrostatic type that continuously shifts and outputs the rotational power input from the engine (3). With the speed changer (41),
An auxiliary transmission (51) that shifts and outputs the rotational power output from the continuously variable transmission (41) to a plurality of stages, and
A traveling vehicle body (2) traveling by receiving rotational power output from the auxiliary transmission (51), and a traveling vehicle body (2).
A shaft rotation mechanism (60) that rotates the trunnion shaft (47), and
A speed change control tool (23, 18) that adjusts the rotation angle of the trunnion shaft (47) by operating the shaft rotation mechanism (60) according to the amount of depression to change the vehicle speed of the traveling vehicle body (2). )When,
An angle sensor (97) that detects the rotation angle of the trunnion shaft (47), and
A button that can exert a function of memorizing the engine rotation speed corresponding to the vehicle speed and the rotation angle of the trunnion shaft (47), and a vehicle speed memory button (28) that can be turned on only while being pressed. ,
When the vehicle speed memory button (28) is pressed and held for a predetermined time or longer while the accelerator operation tool (15, 16) and the speed change operation tool (23, 18) are operated, the vehicle speed at that time is reached. The corresponding engine speed and the rotation angle of the trunnion shaft (47) are stored and held in the storage means (101), and the stored engine speed and the rotation angle of the trunnion shaft (47) are maintained. The first function for controlling the engine (3) and the shaft rotation mechanism (60) so as to travel, and the accelerator operating tool (15, 16) and the shifting operating tool (23, 18) are operated during traveling. When the vehicle speed memory button (28) was briefly pressed for less than a predetermined time, the engine speed and the rotation angle of the trannyon shaft (47) stored in the storage means (101) were maintained. A control device (100) having a second function of controlling the shaft rotation mechanism (60) so as to travel, and a control device (100).
It is a work vehicle characterized by being equipped with.

According to the second aspect of the present invention, the control device (100) notifies by generating a sound when the engine speed and the rotation angle of the trunnion shaft (47) are stored in the first function. The work vehicle according to claim 1, which is characterized by this.

According to the third aspect of the present invention, the control device (100) is released from running while maintaining the engine rotation speed and the rotation angle of the trannyon shaft (47) stored in the first function and the second function. In the case, the work vehicle according to claim 1 or 2, wherein when the vehicle speed information stored in the storage means (101) remains, the remaining information is notified by lighting the display. be.

According to the fourth aspect of the present invention, the control device (100) is selected for the storage means (101) by the engine speed and the rotation angle of the trunnion shaft (47) in the first function. The gear shift of the auxiliary gearbox (51), which is controlled to be stored in combination with the gear shift of the sub-transmission device (51) and is selected when the short press operation is performed in the second function, is , Sound is generated when the combination of the engine speed stored in the storage means (101) and the rotation angle of the trannyon shaft (47) and the shift stage of the auxiliary transmission (51) does not match. The shaft rotation mechanism (60) is controlled so that the engine speed and the rotation angle of the tranny shaft (47) are not maintained while notifying by at least one of the lighting of the display. The work vehicle according to any one of claims 1 to 3.

According to the fifth aspect of the present invention, when the vehicle speed memory button (28) is pressed for a predetermined time or longer while the control device (100) is stopped, the engine rotation is stored in the storage means (101). The work vehicle according to any one of claims 1 to 4, wherein the information on the number and the rotation angle of the trannyon shaft (47) is erased.

In the invention according to claim 1, when the vehicle speed memory button (28) is long-pressed for a predetermined time or longer while traveling while operating the accelerator operation tool (15, 16) and the speed change operation tool (23, 18). , The engine speed and the rotation angle of the tranny shaft (47) at that time are stored in the storage means (101), and in addition, the stored engine speed and the rotation of the tranny shaft (47) are stored. The running is done while keeping the moving angle. Further, when the vehicle speed memory button (28) is short-pressed for less than a predetermined time while the accelerator operation tool (15, 16) and the speed change operation tool (23, 18) are operated, the vehicle speed memory button (28) is stored in the storage means (101). The running is performed while maintaining the engine speed and the rotation angle of the trunnion shaft (47).

As a result, according to the present invention, the driver performs an act of pressing and holding the vehicle speed memory button (28) while driving, so that it becomes easier for the driver to grasp the vehicle speed to be stored during driving. Further, it is possible to continue traveling at the vehicle speed and reproduce the traveling at the vehicle speed by a simple operation of long-pressing or short-pressing the vehicle speed memory button (28).

According to the second aspect of the present invention, when the engine speed and the rotation angle of the trunnion shaft (47) are memorized, the sound is generated to notify the driver, so that the vehicle speed that the driver wants to memorize while driving is memorized. It will be possible to recognize what has been done by hearing, and it will be easier to grasp the vehicle speed.

According to the third aspect of the present invention, when the traveling maintained at the engine rotation speed and the rotation angle of the tranny shaft (47) is canceled, the vehicle speed information stored in the storage means (101) remains. Sometimes the remaining vehicle is notified by lighting the display, so the driver can visually recognize that the vehicle speed that he / she wants to memorize when driving is memorized and remains, and can better grasp the vehicle speed. It will be easier.

According to the fourth aspect of the present invention, the storage means (101) is combined with the shift stage of the auxiliary transmission (51) in which the engine speed and the rotation angle of the tranny shaft (47) are selected at that time. Therefore, it becomes possible to memorize the vehicle speed that the driver wants to memorize for each shift stage, and the convenience is improved. Further, when the combination of the engine speed and the rotation angle of the trannyon shaft (47) stored in the storage means (101) and the shift stage of the auxiliary transmission (51) does not match, a sound is generated. Is notified by at least one of the lighting of the indicator, and the vehicle is not driven while maintaining the engine speed and the rotation angle of the tranny shaft (47). As a result, it is found that the gear shift of the auxiliary transmission selected by the driver is inappropriate, and unexpected driving due to a combination of the vehicle speed and the shift gear is prevented from occurring, and safety is ensured. ..

According to the invention according to claim 5, when the vehicle speed memory button (28) is pressed and held for a predetermined time or longer while the vehicle is stopped, the engine speed and the tranion shaft (1) stored in the storage means (101) are stored. Since the information on the rotation angle of 47) is erased, the driver can use the unnecessary engine speed and the rotation of the trannyon shaft (47) when it becomes unnecessary because the vehicle speed at the time of storage does not match. It is possible to erase the information on the moving angle, and it is possible to prevent unnecessary use of the vehicle speed and wasteful running while maintaining the vehicle speed.

It is a left side view of the tractor which concerns on embodiment of this invention. It is a top view of the tractor of FIG. It is a power transmission diagram of a power transmission device. It is a schematic diagram which shows the structure and operation state of the hydrostatic type continuously variable transmission. It is a schematic plan view which shows the structure of a part of an adjustment panel. It is a block diagram which shows the structure of a part of the control system of a tractor. It is a conceptual diagram which shows an example of the control operation about a memory vehicle speed cruise, (A) is a conceptual diagram which shows the execution example of the 1st function and 2nd function, (B) shows the execution example which includes the additional configuration of the 1st function. It is a conceptual diagram.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

1 and 2 show a tractor 1 which is an example of a work vehicle according to an embodiment of the present invention.

The tractor 1 includes a traveling vehicle body 2 on which devices such as an engine 3, a power transmission device 4, a pair of left and right front wheels 5, rear wheels 6, and a cockpit 7 are mounted or provided on a support frame or the like (not shown). Of these, the engine 3 is covered with a bonnet cover 11 provided so as to be openable and closable. The power transmission device 4 is composed of a hydrostatic continuously variable transmission (HST) 41, an auxiliary transmission 51, and the like arranged in the transmission case 40.

Further, the tractor 1 is driven by four-wheel drive (4WD) in which the rotational power of the engine 3 is transmitted to the left and right front wheels 5 and the left and right rear wheels 6 via the power transmission device 4 and the like, and the left and right rear wheels 6. The drive system can be switched between the two-wheel drive (2WD) that is transmitted and driven, and the vehicle travels by one of the drive systems. The traveling speed (vehicle speed) of the traveling vehicle body 2 is detected by the vehicle speed sensor 92 (FIG. 6), and the detection information is transmitted to the control device 100.

Further, the tractor 1 can perform a desired work by attaching a work machine (not shown) such as a rotary tiller to the rear part of the traveling vehicle body 2 via a mounting portion such as a lower link 29. At the rear of the traveling vehicle body 2, a PTO shaft 59 for outputting the rotational power of the engine 3 to the mounted work machine is provided.

The cockpit 7 has a seat portion 7a on which the driver sits and a step floor portion 7b on which the driver puts his / her feet when riding or driving.

In front of the cockpit 7, a steering wheel (handle) 12 is provided to steer the front wheels 5 by rotating left and right around a shaft (not shown) supported by the handle post 20 provided on the support frame of the traveling vehicle body 2. ing. In front of the steering wheel 12, a display panel 13 for displaying information on maneuvering (driving speed, operating state, etc.) to the driver is provided.

A forward / backward switching lever 14 that is operated when switching between forward traveling and reverse traveling is provided at the upper left end of the steering wheel 12 at the upper end of the handle post 20. The forward / backward switching lever 14 has three switching positions of a forward position, a neutral position, and a reverse position. The selected position is detected by the forward / backward switching position sensor 93 (FIG. 6), and the detection information is detected by the control device 100. Will be sent to.

Further, an accelerator lever 15 for changing the rotation speed of the engine 3 is provided at the other end of the upper part of the handle post 20 and below the steering wheel 12. The accelerator lever 15 is an example of an accelerator operating tool, and is used during work travel. Further, the accelerator lever 15 is held at that position even if the hand is released at the operated position, and the operation amount is detected by the accelerator lever position sensor 74 (FIG. 6) and the detection information thereof. Is transmitted to the control device 100.

The step floor portion 7b of the driver's seat 7 is provided with an accelerator pedal 16, left and right brake pedals 17L and 17R, an HST pedal 18, a clutch pedal 19, and the like on a portion on the right side of the handle post 20. The left and right brake pedals 17L and 17R can switch between a connected state in which the left and right are operated simultaneously by the connecting member and a non-connected state in which the left and right can be operated respectively, and the brake pedals that detect whether the left and right brake pedals are in the connected state or the non-connected state. A coupling sensor 81 (FIG. 6) is provided. If the operation of the accelerator pedal is detected by the detection value of the accelerator pedal position sensor 95 (FIG. 6) while the brake pedal connection sensor 81 is detecting the unconnected state, it is notified by a lamp, a buzzer, or both, which is unsafe. Suppress running.

The accelerator pedal 16 is an example of an accelerator operating tool, and is a pedal that is operated when the engine speed and the vehicle speed of the traveling vehicle body 2 are increased according to the amount of depression. The accelerator pedal 16 is basically used when traveling on the road. Further, the accelerator pedal 16 is detected by the accelerator pedal position sensor 95 (FIG. 6), and the detection information is transmitted to the control device 100.

The HST pedal 18 is an example of a speed change operation tool, and the rotation direction and rotation speed (rotation speed) of the rotational power output from the stepless transmission 41 made of the HST according to the stepping direction and the amount thereof, and the traveling vehicle body. This is a seesaw-type step-on pedal that is operated when changing the traveling direction (forward or reverse) and adjusting the vehicle speed. The HST pedal 18 is mainly used during work running.

The HST pedal 18 has a stop operation position that can be put into a stop state by keeping the entire pedal in a substantially horizontal state, and a step forward by depressing the entire pedal so as to tilt forward from the stop operation position. It has a forward operation range in which the vehicle speed can be increased / decreased, and a reverse operation range in which the vehicle speed at the time of reverse can be increased / decreased by depressing the entire pedal so as to tilt backward from the stop operation position. Further, the stepping direction and amount of the HST pedal 18 are detected by the HST pedal position sensor 96 (FIG. 6), and the detection information is transmitted to the control device 100.

An auxiliary shift lever 21, a PTO clutch lever 22, a main shift lever 23, and the like are provided on the left side of the cockpit 7 with respect to the forward direction.

The auxiliary shift lever 21 is a lever that operates the rotational speed of the rotational power that transmits the auxiliary transmission device 51 when selecting, for example, one of low speed, medium speed, and high speed shift stages (vehicle speed range). Of these gears, low speed and medium speed are vehicle speed ranges suitable for traveling in the field when working in the field, and high speed is the vehicle speed suitable for traveling on the road when moving between fields. It is a region. The PTO clutch lever 22 is a lever operated when connecting / disconnecting the drive transmission to the PTO shaft 59. The main shifting lever 23 is another example of the shifting operating tool, and is a lever that operates the trunnion shaft 47 of the continuously variable transmission 41 to shift gears.

The selected operation position of the auxiliary shift lever 21 is detected by the auxiliary shift position sensor 95 (FIG. 6), and the detection information is transmitted to the control device 100. The shift lever 23 has its selected operating position detected by the main shift position sensor 99 (FIG. 6), and the detection information is transmitted to the control device 100.

As shown in FIG. 2, a position lever 24 for raising and lowering the work equipment, an adjustment panel 25, and the like are provided on the right side of the cockpit 7 with respect to the forward direction.

The position lever 24 is an operation lever that adjusts the height of the working machine when it is raised and lowered. The adjustment panel 25 is a portion where dials, switches, and the like for setting necessary adjustments for a part of the operation of the tractor 1 are arranged.

As shown in FIG. 3, in the power transmission device 4, first, the rotational power of the output shaft of the engine 3 is transmitted to the input shaft 32 of the transmission case 40 via the main clutch 31, and the speed increasing gears 33a and 33b. After the speed is increased, it is configured to be transmitted to the input shaft 42 of the stepless speed changer 41. The main clutch 31 operates depending on whether or not the clutch pedal 18 is depressed.

The continuously variable transmission 41 is a device to which the above-mentioned HST is applied, and the hydraulic pump 43 and the hydraulic motor 44 are combined and integrated.

The hydraulic pump 43 is a variable displacement hydraulic pump, which is operated by the rotational power of the engine 3 input through the input shaft 42, and hydraulic oil sent to the hydraulic motor 44 by changing the inclination angle of the swash plate 45 in the pump. Adjust the discharge state (direction and flow rate (including zero)) of. The hydraulic motor 44 is, for example, a fixed-capacity hydraulic motor, and rotates the motor output shaft 44a in a predetermined rotation direction and rotation speed (rotation speed) according to the state of the hydraulic oil discharged from the hydraulic pump 43.

Then, in the power transmission device 4, as shown in FIG. 3, the rotational power of the motor output shaft 44a of the hydraulic motor 44 in the stepless transmission 41 is output through the drive output shaft 34 after passing through the auxiliary transmission 51. It is later transmitted to the left and right rear wheels 6 via the rear wheel differential gear device 35.

Further, in the power transmission device 4, when the drive switching device 36 including the connecting gear is switched to the four-wheel drive side, the rotational power output from the auxiliary transmission 51 through the drive output shaft 34 passes through the drive switching device 36. After being transmitted to the front wheel relay shaft 37, it is also transmitted to the left and right front wheels 5 via the front wheel speed increasing device 38 and the front wheel differential gear device 39. The front wheels 5 transmit rotational power that is faster than that of the rear wheels 6 only when the front wheel speed increasing device 38 is activated and the speed is increased, but otherwise, the rotational power of the same rotational speed as that of the rear wheels 6 is transmitted. Be transmitted.

Further, as shown in FIG. 3, the power transmission device 4 is provided with a pump output shaft 43a that rotates in the same manner as the input shaft 42 in the hydraulic pump 43 in the continuously variable transmission 41. As a result, in the power transmission device 4, the rotational power of the pump output shaft 43a is transmitted to the PTO relay shaft 57 via the PTO forward / reverse clutch 56 and then to the PTO shaft 59 via the PTO transmission device 58.

In the continuously variable transmission 41, the swash plate 45 in the hydraulic pump 43 is switched to any of the forward output position, the neutral position, and the reverse output position.

When the swash plate 45 is switched to the forward output position, the stepless speed changer 41 outputs power from the motor output shaft 44a to rotate in the direction in which the hydraulic motor 44 advances and at a rotation speed according to the tilt angle, and also tilts. When the plate 45 is switched to the reverse output position, the hydraulic motor 44 outputs power to rotate in the reverse direction and at a rotation speed according to the inclination angle from the motor output shaft 44a. On the other hand, in the continuously variable transmission 41, when the swash plate 45 is switched to the neutral position, the hydraulic motor 44 does not rotate the motor output shaft 44a and does not output power.

Further, as shown in FIG. 4, the continuously variable transmission 41 has a trunnion shaft 47 that rotates so as to adjust the inclination angle of the swash plate 45 in the hydraulic pump 43. The trunnion shaft 47 is rotated via a trunnion arm 48 that is moved by the operation of the shaft rotation mechanism 60.

The shaft rotation mechanism 60 has a hydraulic cylinder mechanism 61 as a drive source and a link mechanism 65 for transmitting the power of the hydraulic cylinder mechanism 61 to the trunnion arm 48.

The hydraulic cylinder mechanism 61 includes a double-acting hydraulic cylinder 62 and a control valve 63 for operating the hydraulic cylinder 62.

The link mechanism 65 includes a first swing arm 67 having one end connected to the tip of the piston rod 62a of the hydraulic cylinder 62 in the hydraulic cylinder mechanism 61 and rotatably supported by the first fixed shaft 66a, and a trunnion. A second swing arm 68, one end of which is connected to the rear end of the arm 48 and rotatably supported by the second fixed shaft 66b, and the other end and the second swing of the first swing arm 67. It is composed of a connecting arm 69 that is rotatably connected to the other end of the arm 68.

The control valve 63 supplies hydraulic oil sent from a hydraulic pump for a cylinder (not shown) to one end and the other end of the double acting cylinder portion 62b at a required timing, thereby extending or shortening the piston rod 62a. As the control valve 63, an electromagnetic hydraulic proportional valve provided with a pair of solenoids 63a and 63b for controlling the hydraulic oil supply operation is applied, one solenoid 63a is operated for extension, and the other solenoid 63b is operated. It is designed to be operated for shortening. Reference numeral 64 in FIG. 4 indicates an oil feed pipe connecting the control valve 63 and one end and the other end of the cylinder portion 62b, respectively.

When the shaft rotation mechanism 60 extends the piston rod 61a of the hydraulic cylinder mechanism 61 from the position corresponding to the neutral position shown in FIG. 4 in the direction indicated by the arrow D1 by the hydraulic oil supply operation of the control valve 63, The force of the extending piston rod 61a is transmitted to the trunnion arm 48 via the link mechanism 62, and the trunnion arm 48 at this time operates so as to rotate the trunnion shaft 47 in the direction indicated by the arrow E1. In this case, the swash plate 45 in the hydraulic pump 43 is moved so as to be inclined toward the forward output position.

Further, when the shaft rotation mechanism 60 shortens the piston rod 61a of the hydraulic cylinder mechanism 61 from the position corresponding to the neutral position in the direction indicated by the arrow D2 by the hydraulic oil supply operation of the control valve 63, the shortening piston thereof. The force of the rod 61a is transmitted to the trunnion arm 48 via the link mechanism 62, and the trunnion arm 48 at this time operates so as to rotate the trunnion shaft 47 in the direction indicated by the arrow E2. In this case, the swash plate 45 in the hydraulic pump 43 is moved so as to be inclined toward the reverse output position.

Further, as shown in FIG. 4, the continuously variable transmission 41 is provided with a neutral holding mechanism 49 for holding the trunnion shaft 47 for rotating the swash plate 45 and the trunnion arm 48 in a neutral position.

The neutral holding mechanism 49 is elastic on a cam plate 49a configured to rotate integrally with the trunnion shaft 47 as a support shaft and return to the neutral position, and a peripheral cam portion having a recessed shape of the cam plate 49a. It has a roller 49b that is pressed against the target. The trunnion shaft 47 has a structure in which one end thereof is rotatably connected to a part of the cam plate 49a with respect to the neutral holding mechanism 49.

In the continuously variable transmission 41, when the shaft rotation mechanism 60 does not operate, the trunnion arm 48 is held in the neutral position by the action of the neutral holding mechanism 49 (see FIG. 4), whereby the swash plate 45 is also held in the neutral position. It is designed to move (return). The rotation angle of the trunnion shaft 47 is detected by the trunnion shaft angle sensor 97 (FIG. 6) that confirms the movement of a part of the trunnion arm 48, and the detection information is transmitted to the control device 100.

In the stepless speed change device 41, when the operation amount of the main shift lever 23 is detected by the main shift position sensor 99 or the depression direction and amount of the HST pedal 18 are detected by the HST pedal position sensor 96, each sensor thereof. The drive current values supplied to the solenoids 63a and 63b of the control valve 63 in the shaft rotation mechanism 60 are controlled by the control device 100 according to the detected values of 99 and 96, respectively. As a result, in the continuously variable transmission 41, the trunnion shaft 47 is rotated in a required direction by a required angle according to the amount of depression via the trunnion arm 48.

As a result, in the stepless speed changer 41, the inclination angle of the swash plate 45 in the hydraulic pump 43 is arbitrarily changed in conjunction with the rotation of the tranny shaft 47, and the hydraulic oil discharged from the hydraulic pump 43 to the hydraulic motor 44. Since the direction and the flow rate are adjusted, the hydraulic motor 44 rotates in a required direction through the motor output shaft 44a, and the rotational power that is steplessly changed to the required rotational speed (rotational speed) is output.

As shown in FIG. 5, the adjustment panel 25 is provided with a maximum speed setting dial 26, a cruise travel button 27, a vehicle speed memory button 28, a speed increase switch 29A, a deceleration switch 29B, and the like.

The maximum speed setting dial 26 is a dial-type operating tool that is operated when setting for limiting the maximum speed of the traveling vehicle body 2. The maximum speed at this time can be arbitrarily set by the driver, and the maximum speed that can be set is prepared in the range of, for example, 15 to 30 km / h. The setting information of the maximum speed setting dial 26 is transmitted to the control device 100 (FIG. 6).

When the maximum speed setting dial 26 is set, the rotation angle of the trunnion shaft 47 is adjusted (restricted), so that even if the main shift lever 23 is operated to the maximum or the HST pedal 18 is depressed to the maximum, the tractor 1 is set. You will only be able to get the vehicle speed up to the maximum speed.

The cruise travel switch 27 is an on / off type switch for operating whether or not the cruise travel is executed. The operation information of the cruise travel switch 27 is transmitted to the control device 100 (FIG. 6).

In the tractor 1, when the cruise travel switch 27 is turned on while traveling at a certain speed, the memory 101 in the control device 100 stores the vehicle speed at the time of the operation as the cruise speed, and the traveling speed is the accelerator pedal 16. And the auto cruise control maintained at the cruise speed without depressing the HST pedal 18 is started by the control device 100.

The vehicle speed memory button 28 is a push button capable of exerting a function of storing the engine rotation speed corresponding to the vehicle speed and the rotation angle of the trunnion shaft 47. The vehicle speed memory button 28 is a button that can be turned on only while it is being pressed, and returns to its original position when it is pressed by hand and then released (self-returning button).

Further, as will be described later, the vehicle speed memory button 28 has a function of being activated by a long press operation that is longer than a predetermined time or a short press operation that is shorter than a predetermined time during traveling or stopping. The predetermined time is arbitrarily set, and for example, a time of about 1 second is set.

The speed-up switch 29A and the deceleration switch 29B increase the cruise speed and the memory speed during the execution of the auto cruise control or the memory vehicle speed cruise (constant speed running at the memory vehicle speed) control described later by operating the vehicle speed memory button 28. A push-button switch that is operated to adjust for speed or deceleration. Each operation information of the speed increase switch 28A and the deceleration switch 28B is transmitted to the control device 100.

Then, in the tractor 1, the control device 100 controls the control related to the memory vehicle speed cruise as follows.

The control device 100 is composed of an arithmetic processing unit, a memory 101 as a storage means, an input / output device, and the like, and is necessary for the operation of the controlled object based on the control program and data stored in a part of the memory 101. It is designed to perform various controls. The memory 101 includes not only storage elements such as ROM and RAM but also a storage device such as a hard disk.

In the tractor 1, for example, when the driver wants to memorize the vehicle speed while working at an arbitrary vehicle speed by operating the accelerator lever 15 and the HST pedal 18 in the field, the driver presses the vehicle speed memory button 28. Press and hold for a specified time or longer.

In this case, in the tractor 1, the control device 100 stores and holds the engine rotation speed and the rotation angle of the trannyon shaft 47 corresponding to the vehicle speed in the memory 101, and the stored engine rotation speed and the stored engine rotation speed. An operation of controlling the shaft rotation mechanism 60 is performed so as to travel while maintaining the rotation angle of the tranion shaft 47. The series of control operations at this time is executed as the "first function".

At this time, in the control device 100, as shown in FIG. 6, the trunnion shaft control unit 103 controls the operation of the control valve 63 in the shaft rotation mechanism 60.

The trunnion shaft control unit 103 controls the drive current values supplied to the solenoids 63a and 63b of the control valve 63 according to the detection values of the HST pedal position sensor 96 in a predetermined relationship. The rotation angle of the trunnion shaft 47 stored in the memory 101 is stored as, for example, a drive current value supplied to the solenoids 63a and 63b when the vehicle speed memory button 28 is pressed and held for a long time.

When the trunnion shaft control unit 103 performs auto-cruise control, which will be described later, the drive current supplied to the solenoids 63a and 63b of the control valve 63 according to the detection value of the main shift position sensor 99 when the control is started. The value is also controlled by a predetermined relationship.

Further, the rotation speed of the engine 3 is detected by the engine rotation speed sensor 72, and the rotation speed when the vehicle speed memory button 28 is pressed and held is stored.

As a result, in the tractor 1, as conceptually shown in the left half of FIG. 7A, the engine speed and the rotation angle of the trunnion shaft 47 corresponding to the vehicle speed when the vehicle speed memory button 28 is pressed and held for a long time. Is stored and held in the memory 101, and constant speed traveling (memory vehicle speed cruise) maintained at the stored engine speed and the rotation angle of the trunnion shaft 47 is continued. That is, the first function is executed.

Therefore, according to this tractor 1, since the driver performs an act of pressing and holding the vehicle speed memory button 28 while driving, it becomes easy for the driver to grasp the vehicle speed that he / she wants to store during driving. Further, the continuation of constant speed running at the memory vehicle speed can be easily realized by a single operation of long-pressing the vehicle speed memory button 28.

Further, in the tractor 1, when the accelerator lever 15 and the HST pedal 18 are operated to drive at an arbitrary vehicle speed, the driver wants to travel at a stored memory vehicle speed instead of the arbitrary vehicle speed. , The driver short-presses the vehicle speed memory button 28.

In this case, in the tractor 1, the control device 100 controls the shaft rotation mechanism 60 so as to keep the engine speed and the rotation angle of the trunnion shaft 47 stored in the memory 101. The control operation at this time is executed as a "second function".

At this time, as in the case of the first function, in the control device 100, as shown in FIG. 6, the operation of the control valve 63 in the shaft rotation mechanism 60 is controlled by the trunnion shaft control unit 103. There is. At this time, the trunnion shaft control unit 103 determines in advance the drive current values to be supplied to the solenoids 63a and 63b of the control valve 63 based on the rotation angle of the trunnion shaft 47 corresponding to the memory vehicle speed stored in the memory 101. It is controlled by the relationship.

Further, the detection value of the engine rotation speed sensor 72 is fed back so as to be the stored engine rotation speed, and the fuel injection timing and the injection amount of the engine 3 are controlled.

As a result, in the tractor 1, as conceptually shown in the right half of FIG. 7A, when the vehicle speed memory button 28 is briefly pressed, the memory vehicle speed stored and held in the memory 101 is maintained. Driving (memory vehicle speed cruise) is reproduced. That is, the second function is executed.

Therefore, according to the tractor 1, it is possible to easily reproduce the running at the stored memory vehicle speed by a single operation of short-pressing the vehicle speed memory button 28 during the running.

In addition, the control device 100 is configured to perform an operation of notifying the engine rotation speed and the rotation angle (vehicle speed) of the trunnion shaft 47 by generating a sound when they are stored in the memory 101 in the first function.

At this time, as a sound generation, the control device 100 operates a sound generation unit 13b such as a buzzer attached to the display panel 13 or the like by the panel drive control unit 104 to generate a required sound, as shown in FIG. (For example, the buzzer sounds).

As a result, the driver can hear and recognize that the vehicle speed that he / she wants to store during driving is stored in the memory 101 when the vehicle speed memory button 28 is pressed and held in the first function. It becomes easier to grasp the vehicle speed when you want.

In this case, instead of or in addition to the notification by the generation of the sound, the vehicle speed memory button 28 may be turned on when the sound is stored in the memory 101 to notify the notification.

Further, when the traveling (memory vehicle speed cruise) maintained at the engine rotation speed and the rotation angle of the tranny shaft 47 is canceled in the first function and the second function, the control device 100 stores the vehicle speed stored in the storage means 101. When the information (engine speed and rotation angle of the trunnion shaft 47) remains, the operation of notifying the remaining information by lighting the display is also performed.

In this case, the control device 100 operates the display screen unit 13a attached to the display panel 13 or the like by the panel drive control unit 104 to turn on the display, as shown in FIG. 6, and the required display screen ( Indicator display), to turn on the mark, etc., and to turn on the notification lamp.

Further, the release of the memory vehicle speed cruise is operated by short-pressing the vehicle speed memory button 28, depressing the brake pedal 17, and depressing the HST pedal 18 when the memory vehicle speed cruise is executed. That is done, the accelerator lever 15 is operated, and the like. Whether or not the brake pedal 17 is depressed is detected by the brake pedal position sensor 98 (FIG. 6), and the detection information is transmitted to the control device 100.

As a result, when the memory vehicle speed cruise is canceled in the first function or the second function, the driver is notified by lighting the display, so that the driver can visually recognize that the memory vehicle speed is stored and remains. Therefore, it becomes easier to grasp that the memory vehicle speed is in the memory 101.

Further, when the vehicle speed memory button 28 is pressed and held for a predetermined time or longer while the tractor 1 is stopped, the control device 100 performs an operation of erasing the memory vehicle speed information stored in the memory 101. It has become like.

As a result, the tractor 1 can erase the vehicle speed information stored in the memory 101 by the driver. Therefore, for example, when changing the working machine to perform different work or working in a different field. It is possible to prevent misuse by reproducing constant speed running at an unnecessary memory vehicle speed that does not match when the situation is such as when the vehicle is used.

In this case, the predetermined time for determining the long press operation is the same as the predetermined time for determining the long press operation for storing the vehicle speed, but it may be set to a different time.

Further, when the brake pedal 17 is depressed during the memory vehicle speed cruise, the operation of erasing the memory vehicle speed information stored in the memory 101 may be performed. With this configuration, it is possible to prevent accidental sudden acceleration at the memory vehicle speed when the brake pedal 17 is released after the depression operation is completed.

On the other hand, the control device 100 is configured to retain the memory vehicle speed information stored in the memory 101 even when the engine 3 is stopped by turning off the key switch memory (not shown).

As a result, in the tractor 1, even if the key switch is turned off during a break or the like, the memory vehicle speed is not erased from the memory 101. Therefore, when the key switch is turned on and the work is restarted, the previous memory vehicle speed remains. Therefore, the memory vehicle speed cruise based on the memory vehicle speed can be easily reproduced, and the workability is improved.

Further, when the speed increase switch 29A or the deceleration switch 29B is turned on during the memory vehicle speed cruise, the control device 100 increases or decelerates the memory vehicle speed by the amount of the turned on operation. It is configured to retain the memory vehicle speed information stored in the memory 101 even when the constant speed running kept at the vehicle speed is controlled and the constant speed running kept at the changed vehicle speed is canceled. ing.

As a result, in the tractor 1, as conceptually shown in the left half of FIG. 7B, the vehicle speed is adjusted by increasing or decreasing depending on the working conditions and conditions while traveling at the memory vehicle speed. It becomes possible to run. Further, in this tractor 1, if there is a case where it is desired to reproduce the constant speed running at the memory vehicle speed before the change after canceling the constant speed running at the changed vehicle speed, the constant speed running at the memory vehicle speed before the change is performed. It can be easily reproduced without performing the operation of memorizing the vehicle speed again.

Further, in the control device 100, when the driver is traveling while maintaining the changed vehicle speed by increasing or decelerating the memory vehicle speed by turning on the speed increase switch 29A or the deceleration switch 29B, the driver presses the vehicle speed memory button 28. When is pressed and held for a long time, the changed vehicle speed is rewritten to the memory 101 and stored in the memory 101.

As a result, in this tractor 1, as conceptually shown in the right half of FIG. 7B, the speed increase switch 29A or the deceleration switch 29B is turned on as necessary during a memory vehicle speed cruise. Therefore, even if the vehicle speed is changed, the changed vehicle speed can be newly stored as a memory vehicle speed, and constant speed running maintained at the changed memory vehicle speed can be easily resumed, which is convenient. By the way, if the vehicle speed memory button 28 is not pressed and held during constant speed running while maintaining the vehicle speed after the change by turning on the speed increase switch 29A or the deceleration switch 29B, the changed vehicle speed is the memory 101. Will not be remembered in.

Further, in this tractor 1, as shown in FIG. 5, a cruise traveling button 27 is provided in addition to the vehicle speed memory button 28.

Therefore, in the control device 100, for example, when the accelerator lever 15 and the HST pedal 18 are operated to travel at an arbitrary vehicle speed on a road or the like when moving between fields, the driver presses the cruise travel button 27. Upon operation, the shaft rotation mechanism 60 is controlled so as to perform constant speed traveling while maintaining the engine rotation speed and the rotation angle of the trunnion shaft 47 at that time.

As a result, the tractor 1 can easily perform constant speed traveling (auto cruise) maintained at the cruise vehicle speed at that time without depressing the HST pedal 18. As a result, in this tractor 1, there are two ways of traveling with a fixed vehicle speed, one is by pressing the vehicle speed memory button 28 and the other is by pressing the cruise travel button 27. Convenience is improved.

By the way, in this tractor 1, when the vehicle speed memory button 28 is short-pressed while traveling when the memory vehicle speed information is not stored (does not exist) in the memory 101, the control device 100 changes to the vehicle speed at that time. It may be configured to perform control to execute a fixed run.

In this case, since the vehicle speed memory button 28 has the same usage and function as the cruise travel button 27, it is possible to adopt a configuration in which only the vehicle speed memory button 28 is provided without providing the cruise travel button 27. ..

Further, when the driver presses and holds the vehicle speed memory button 28 while performing auto-cruise at the cruise vehicle speed by pressing the cruise travel button 27, the control device 100 stores the cruise vehicle speed in the memory 101. It may be configured to perform the operation of holding the cruise control.

In this case, the cruise vehicle speed at the time of auto cruise can be memorized and held, and the traveling at the cruise vehicle speed can be reproduced by a short press operation of the vehicle speed memory button 28 (the second function described above). Convenience is improved.

Further, in the tractor 1, the control device 100 selects the engine rotation speed, the rotation angle of the trunnion shaft 47, and the auxiliary transmission lever 21 at that time in the memory 101 in the first function. The operation of storing (associating) with the speed change stage of 51 is performed. In this case, if the vehicle speed memory button 28 is subsequently short-pressed, the memory vehicle speed cruise based on the combination of the stored gear speed of the auxiliary transmission 51 and the memory vehicle speed is reproduced.

Further, in the control device 100 at this time, the engine speed in which the shift stage of the auxiliary transmission 51 selected when the vehicle speed memory button 28 is briefly pressed in the second function is stored in the memory 101. And when the combination of the rotation angle of the trunnion shaft 47 and the shift stage of the auxiliary transmission 51 does not match, at least one of the generation of sound and the lighting of the display is notified, and the engine speed and the trunnion shaft 47 are notified. The operation of controlling the shaft rotation mechanism 60 is also performed so that the vehicle does not travel while maintaining the rotation angle.

As a result, in this tractor 1, since the vehicle speed can be stored for each shift stage of the auxiliary transmission 51, the vehicle speed at the time of movement between fields or on the road is not limited to the shift stage suitable for work driving. It is possible to memorize the vehicle and run at a fixed speed, which improves convenience. Further, in this tractor 1, it is known by the notification that the shift stage of the auxiliary transmission 51 selected by the driver is inappropriate, and unexpected fixed running is performed by the combination of the memory vehicle speed and the shift stage that do not match. This is prevented and safety is ensured.

Further, the control device 100 panel-drives information on the memory vehicle speed stored in the memory 101, information on the combination of the memory vehicle speed and the shift stage, and information related to the memory vehicle speed cruise such as the rotation speed of the engine 3. The control unit 104 is configured to perform an operation of displaying on the display screen unit 13a of the display panel 13.

The display at this time can be configured to be automatically performed in conjunction with the operation of storing the memory vehicle speed, or can be configured to be performed by the operation of switching the display screen by the driver. The screen can be switched by operating the display switching button screen displayed on the display screen unit 13a of the display panel 13, or by operating the display switching button provided on the side of the display panel 13.

As a result, the driver can easily visually confirm the information related to the memory vehicle speed cruise. In addition, the driver can also use information related to the memory vehicle speed cruise, correct the information, delete the information, and the like, which improves usability.

Further, in the control device 100, the shift stage of the auxiliary transmission 51 selected when the vehicle speed memory button 28 is briefly pressed in the second function is the memory vehicle speed (engine rotation speed) stored in the memory 101. And, when the combination of the rotation angle of the trunnion shaft 47) and the shift stage of the auxiliary transmission 51 does not match, the information of the mismatched combination is displayed on the display screen unit 13a of the display panel 13. Has been done.

As a result, the driver can easily know what the inappropriate gear of the auxiliary transmission 51 is, and can easily and accurately change the inappropriate gear to an appropriate gear. You can also do it.

In this case, the control device 100 is configured to perform an operation of lighting and displaying on the display panel 13 that the memory vehicle speed cruise is reproducible and an operation of lighting the vehicle speed memory button 28 when the combinations match. You may.

Further, when the control device 100 has a memory vehicle speed stored in the memory 101, the operation of the auxiliary shift lever 21 selects a shift stage of the auxiliary transmission 5 that does not match the stored memory vehicle speed. Is performed, the operation of erasing the memory vehicle speed information stored in the memory 101 is performed.

As a result, it is possible to prevent an inappropriate memory vehicle speed cruise from being executed in combination with the shift stage of the auxiliary transmission 51 that does not match the memory vehicle speed, and it is possible to prevent the occurrence of erroneous operation. By the way, if an operation is performed to select a gear that does not match the memory vehicle speed as the gear, traveling in combination with a gear that does not match the rotation angle (opening) of the trunnion shaft corresponding to that memory vehicle speed will actually occur. The vehicle speed is different from the memory vehicle speed, and the desired memory vehicle speed cruise cannot be accurately reproduced.

<Modification example>
In the above embodiment, as an operation example of the control device 100, the case where the first function and the second function are executed when traveling by operating the accelerator lever 15 and the HST pedal 18 has been described. The control device 100 in the present invention can similarly execute the first function and the second function when traveling by operating the accelerator pedal 16 and the main speed change lever 23.

Further, in the tractor 1, the control device 100 is configured to display and notify the display screen unit 13a of the display panel 13 that the memory vehicle speed cruise is in progress when the vehicle is traveling in the memory vehicle speed cruise. You may. The display of the memory vehicle speed cruise may be performed, for example, by displaying or lighting a display screen or a mark indicating that the memory vehicle speed cruise is in progress.

With such a configuration, it is possible to easily and surely recognize that the driver is automatically traveling on the memory vehicle speed cruise.

Further, in the tractor 1, the control device 100 notifies the display screen portion 13a of the display panel 13 that the vehicle shifts to the memory vehicle speed cruise when the vehicle shifts from traveling at an arbitrary vehicle speed to the memory vehicle speed cruise. It should be configured to perform the operation. Notification of the shift to the memory vehicle speed cruise may be performed, for example, by blinking a display screen or a mark indicating the shift to the memory vehicle speed cruise.

In this configuration, the driver does not change the vehicle speed due to the operation of the main shift lever 23 or the HST pedal 18, but the vehicle speed changes due to the shift to the memory vehicle speed cruise. Temporary fluctuations can be easily and reliably recognized, which can also alert the driver.

Further, the tractor 1 is configured to release the control related to the memory vehicle speed cruise (control to perform fixed travel at the memory vehicle speed) when the auto cruise travel switch 27 is pressed during the travel of the memory vehicle speed cruise. You may.

Further, in the above tractor 1, when the operation of the accelerator pedal is detected by the detection value of the accelerator pedal position sensor 95 (FIG. 6) when the brake pedal connection sensor 81 detects the non-connection state, the lamp or buzzer or the buzzer thereof is detected. Although the configuration for notifying by both is shown, the inclination of the vehicle body by the inclination sensor, the operation position of the auxiliary shift lever, the operation position of the PTO lever, etc. may be added as the notification condition.

The present invention is not limited to vehicles for agricultural work such as tractors, but can also be applied to vehicles for various other work.

1 ... Tractor (working vehicle)
2 ... Running body 3 ... Engine 15 ... Accelerator lever (accelerator operator)
16 ... Accelerator pedal (accelerator operator)
18 ... HST pedal (shift control tool)
23 ... Main shift lever (shift control tool)
28 ... Vehicle speed memory switch 41 ... Continuously variable transmission (hydrostatic continuously variable transmission)
42 ... Auxiliary transmission 47 ... Trunnion shaft 60 ... Trunnion rotation mechanism 97 ... Trunnion shaft angle sensor 100 ... Control device 101 ... Memory (storage means)

Claims (5)

Engine (3) and
Accelerator operating tools (15, 16) that adjust the engine speed according to the amount of operation,
An engine rotation speed sensor (72) that detects the rotation speed of the engine (3), and
It has a trunnion shaft (47) that rotates to adjust the tilt angle of the swash plate (45), and is a hydrostatic type non-hydrostatic type that continuously shifts and outputs the rotational power input from the engine (3). With the speed changer (41),
An auxiliary transmission (51) that shifts and outputs the rotational power output from the continuously variable transmission (41) to a plurality of stages, and
A traveling vehicle body (2) traveling by receiving rotational power output from the auxiliary transmission (51), and a traveling vehicle body (2).
A shaft rotation mechanism (60) that rotates the trunnion shaft (47), and
A speed change control tool (23, 18) that adjusts the rotation angle of the trunnion shaft (47) by operating the shaft rotation mechanism (60) according to the amount of depression to change the vehicle speed of the traveling vehicle body (2). )When,
An angle sensor (97) that detects the rotation angle of the trunnion shaft (47), and
A button that can exert a function of memorizing the engine rotation speed corresponding to the vehicle speed and the rotation angle of the trunnion shaft (47), and a vehicle speed memory button (28) that can be turned on only while being pressed. ,
When the vehicle speed memory button (28) is pressed and held for a predetermined time or longer while the accelerator operation tool (15, 16) and the speed change operation tool (23, 18) are operated, the vehicle speed at that time is reached. The corresponding engine speed and the rotation angle of the trunnion shaft (47) are stored and held in the storage means (101), and the stored engine speed and the rotation angle of the trunnion shaft (47) are maintained. The first function for controlling the engine (3) and the shaft rotation mechanism (60) so as to travel, and the accelerator operating tool (15, 16) and the shifting operating tool (23, 18) are operated during traveling. When the vehicle speed memory button (28) was briefly pressed for less than a predetermined time, the engine speed and the rotation angle of the trannyon shaft (47) stored in the storage means (101) were maintained. A control device (100) having a second function of controlling the shaft rotation mechanism (60) so as to travel, and a control device (100).
A work vehicle characterized by being equipped with. The first aspect of the present invention, wherein the control device (100) notifies by generating a sound when the engine speed and the rotation angle of the trunnion shaft (47) are stored in the first function. Work vehicle. When the running kept at the engine rotation speed and the rotation angle of the trunnion shaft (47) stored in the first function and the second function is released, the control device (100) is stored in the storage means (101). The work vehicle according to claim 1 or 2, wherein when the stored vehicle speed information remains, the remaining information is notified by lighting the display. The control device (100) has the storage means (101) in the first function, the engine speed, the rotation angle of the trannyon shaft (47), and the auxiliary transmission (51) selected at that time. The shift stage of the auxiliary transmission (51) selected when the short press operation is performed in the second function is stored in the storage means (101). When the combination of the engine speed and the rotation angle of the trannyon shaft (47) and the shift stage of the auxiliary transmission (51) does not match, sound is generated and the indicator is lit at least one of them. 1. The work vehicle described in the section. When the vehicle speed memory button (28) is pressed for a predetermined time or longer while the control device (100) is stopped, the engine speed and the trannyon shaft (47) stored in the storage means (101) are operated. The work vehicle according to any one of claims 1 to 4, wherein the information on the rotation angle is erased.

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