JP2002106407A - Method for automatically correcting workvehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for automatically correcting a workvehicle, when preset relating data showing the correlation between the detected values measured by a device for detecting numbers of revolutions under unloading conditions without loading to the engine and the detected values measured by a opening sensor, then the relating data can be corrected easily. SOLUTION: When the detected values measured by the device 68 for detecting numbers of revolution under unloading condition are approximately constant and also approximately constant conditions of the detected values measured by the opening sensor 63 are maintained within only for predetermined time, then there is provided a method for automatically correcting the relating data C1, C2 and C3 which are memorized in memory devices, on the basis of these detected values measured by the device 68 for detecting numbers of revolutions under the unloading condition and the detected values measured by the opening sensor 63.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a work vehicle, in which no load is applied to the engine, the engine speed and the accelerator opening (for example, the operation position of a hand accelerator lever and the position of a control rack of a governor). Etc.).

[0002]

2. Description of the Related Art A work vehicle is provided with a rotational speed detecting means for detecting the rotational speed of the engine and an opening sensor (for example, a potentiometer type) for detecting the accelerator opening of the engine, so that no load is applied to the engine. There is a device provided with storage means for setting relational data indicating the relation between the detection value of the rotation speed detecting means and the detection value of the opening degree sensor in the above, and storing the relational data.

[0003] Thus, for example, during work traveling, based on the detection value of the rotation speed detection means and the detection value of the opening degree sensor,
There is a configuration in which a load applied to the engine is detected from the related data, and a configuration in which the load applied to the engine is used for control at the time of operating a transmission for traveling or the like.

[0004]

As described in the prior art, when the opening degree of the accelerator of the engine is detected by an opening sensor, the actual accelerator operation of the engine may occur due to aging due to long-term use. A gap may occur between the opening and the detection value of the opening sensor. As a result, when the relationship data indicating the relationship between the detection value of the rotation speed detection means and the detection value of the opening sensor in a no-load state where no load is applied to the engine is set, it is necessary to correct the relationship data. Come.

The present invention provides a work vehicle including a rotation speed detection means for detecting the rotation speed of the engine, an opening sensor for detecting the accelerator opening of the engine, and a rotation speed in a no-load state where no load is applied to the engine. An object of the present invention is to provide a configuration in which, when relation data indicating a relation between a detection value of a detection unit and a detection value of an opening sensor is set, the relation data can be easily corrected.

[0006]

According to a first aspect of the present invention, there is provided a work vehicle including a rotation speed detecting means for detecting a rotation speed of an engine, and an opening sensor for detecting an accelerator opening of the engine. According to the first aspect of the present invention, when relation data indicating a relation between a detection value of the rotation speed detection means and a detection value of the opening degree sensor in a no-load state where no load is applied to the engine is set, If the state in which the detection value of the rotation speed detecting means in the load state is substantially constant and the detection value of the opening degree sensor is substantially constant for a set time, the rotation speed detection means in the no-load state at that time And the related data are automatically corrected based on the detection value of the opening degree sensor and the detection value of the opening degree sensor. This eliminates the need for the driver or the like to artificially correct the related data.

[II] In a work vehicle, for example, the work traveling is temporarily stopped, and the machine body and the working device are stopped (for example, the main clutch is disengaged, the traveling transmission is operated to a neutral position, and The work clutch for transmitting power is disengaged or operated), the working device is adjusted, or the operator may take a rest. In such a state, the engine is in a no-load state, and the accelerator opening of the engine is also substantially constant. Therefore, the detection value of the rotation speed detecting means in the no-load state becomes substantially constant, and the detection value of the opening degree sensor becomes It is almost constant.

As described above, according to the first aspect of the present invention, it can be said that the work vehicle is almost always present in the work of the day (a state in which the work traveling is temporarily stopped and the machine body and the working device are stopped). As described in the preceding section [I], the configuration in which the correction of the related data is performed does not cause a situation in which the correction of the related data is forgotten and not performed.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [1] FIG. 1 shows a transmission case 8 of a four-wheel drive type agricultural tractor as an example of a work vehicle, in which the power of an engine 1 is transmitted by a transmission shaft 2 and a hydraulic multi-plate PTO clutch. 3 to the PTO shaft 4.
The power of the engine 1 is a forward clutch 5 or a reverse clutch 6, a cylindrical shaft 7, a first main transmission 10, a second main transmission 1.
1, transmitted to the right and left rear wheels 14 via the auxiliary transmission 12 and the rear wheel differential device 13. The power branched immediately before the rear wheel differential device 13 is transmitted to the transmission shaft 15, a hydraulic clutch type front wheel transmission device 16, a front wheel transmission shaft 17, and a front wheel differential device 18.
, To the right and left front wheels 19.

As shown in FIG. 1, the forward clutch 5 and the reverse clutch 6 are of a multi-disc type in which a friction plate (not shown) and a piston (not shown) are combined, and are transmitted by supplying hydraulic oil. Operated to the side. When the forward clutch 5 is operated to the transmission side, the power of the engine 1
, And flows directly to the cylindrical shaft 7 to advance the fuselage. When the reverse clutch 6 is operated to the transmission side, the power of the engine 1 is transmitted through the reverse clutch 6 and the transmission shaft 20 in the reverse state to the cylindrical shaft 7.
The aircraft will move backward.

As shown in FIG. 1, the first main transmission 10 includes four hydraulic multi-plate type first speed clutches 21 and second speed clutches 2.
It is configured as a hydraulic clutch type in which the second-third clutch 23 and the fourth-speed clutch 24 are arranged in parallel and can shift to four speeds, and one of the first- to fourth-speed clutches 21 to 24 is shifted to the transmission side. By operating, the power of the cylindrical shaft 7 is shifted to four stages and transmitted to the transmission shaft 25.

As shown in FIG. 1, the second main transmission 11 is also of a hydraulic clutch type in which two hydraulic multi-plate low-speed clutches 26 and a high-speed clutch 27 are arranged in parallel. By operating one of the clutches 26 and 27 to the transmission side, the power of the transmission shaft 25 is shifted to two stages and transmitted to the auxiliary transmission 12. Auxiliary transmission 1
Reference numeral 2 denotes a synchromesh type that slides the shift member 53 and can be shifted in two stages, and is mechanically operated by a shift lever 28 (see FIG. 2).

[2] Next, the forward and reverse clutches 5,
6. The hydraulic circuit for the first and second main transmissions 10, 11 will be described. As shown in FIG. 3, an electromagnetic proportional valve 35 for the forward and reverse clutches 5, 6 and a pilot-operated switching valve 36a,
37a, pilot operated switching valves 31a, 32a, 33a, 34a for first to fourth speed clutches 21 to 24;
Electromagnetic proportional valve 3 for low and high speed clutches 26 and 27
8, 39 are connected in parallel.

As shown in FIG. 3, a pilot-operated switching valve 42a for a hydraulic clutch 41 for differential lock operation in the front wheel differential device 18 and a differential lock operation in the rear wheel differential device 13 are provided in an oil passage 40 branched from the oil passage 30. A pilot-operated switching valve 44a for the hydraulic clutch 43, a standard clutch 45 for the front wheel transmission 16, and a pilot-operated switching valve 47a, 48a for the speed increasing clutch 46 (see FIG. 1) are connected in parallel. . Switching valves 31a to 34a, 36a, 37a, 42a, 44a,
The springs 47a and 48a are urged toward the oil drain side (transmission blocking side) by springs, and are operated on the supply side (transmission side) when the pilot hydraulic oil is supplied.

[0015] As shown in FIG.
9, the pilot oil passage 50 branches, and the pilot oil passage 50 is connected to the switching valves 31a to 34a, 36a, 37a, 42.
a, 44a, 47a, and 48a are connected to the operation units, and the operation units include electromagnetic operation valves 31b, 32b, 33b, and 34.
b, 36b, 37b, 42b, 44b, 47b, 48b
Is connected. Solenoid operated valves 31b-34b, 36
b, 37b, 42b, 44b, 47b, and 48b are urged by a spring toward the oil discharge side (the transmission cutoff side), and when these are electrically operated to the supply side, the pilot hydraulic oil is switched to the switching valves 31a to 34a. , 36a, 37a, 42a, 44a, 4
These are supplied to the operation units 7a and 48a, and these are operated on the supply side (transmission side).

[3] Next, the forward and reverse clutches 5,
6. The configuration of the operation unit of the first and second main transmissions 10 and 11 will be described. As shown in FIGS. 3 and 2, an opening / closing valve 51 capable of draining the pilot hydraulic oil from the operating portions of the switching valves 36a, 37a of the forward and reverse clutches 5, 6 is provided, and the opening / closing valve 51 is closed by a spring. And a clutch pedal 52 for mechanically operating the on-off valve 51 to the open side is provided. At the base of the steering handle 58 of the front wheel 19,
A forward / reverse lever 59 operable at a forward position F, a reverse position R, and a neutral position N is provided.

As shown in FIG. 2, a speed change lever 28 is swingably supported around a horizontal axis of a control section of the aircraft, and slides a shift member 53 of the auxiliary transmission 12 (see FIG. 1). The shift fork 54 and the speed change lever 28 are mechanically linked by a linking mechanism 55. By operating the shift lever 28 to the neutral position N, the low-speed position L, and the high-speed position H, the sub-transmission 12 (shift member 53)
Can be operated to a neutral position, a low-speed position, and a high-speed position, and a position sensor 70 for detecting an operation position of the shift lever 28 is provided.

As shown in FIG. 2, a lock pin 56 is provided on the lateral side of the shift lever 28 so that the lock pin 56 can be moved back and forth, and an operation button 57 for operating the lock pin 56 is provided above the shift lever 28. Have been. The lock pin 56 is urged by a spring (not shown) to the protruding side (right side in FIG. 2) (the operation button 57 is also urged to the left protruding side in FIG. 2), and is fixed. The shift lever 28 is held at the neutral position N, the low-speed position L, and the high-speed position H by engaging the lock pin 56 with the guide plate 60 of the section. When the operation button 57 is pressed, the lock pin 56 is retracted, and the shift lever 28 can be operated to the neutral position N, the low speed position L, and the high speed position H.

As shown in FIG. 2, a shift-up button 61 and a shift-down button 62 are vertically arranged on the left lateral side of the shift lever 28. The shift-up button 61 and the shift-down button 62 are Once the push operation is performed, one shift-up signal and one shift-down signal are transmitted, and the first and second main transmissions 10 and 11 shown in FIG. 1 are operated.

As shown in FIG. 2, a seven-segment shift display portion 64 for displaying the shift positions (first to eighth speeds) of the first and second main transmissions 10 and 11 is provided. Forward lamp 65 and reverse lamp 6 indicating which of clutches 5 and 6 is being operated on the transmission side.
6. The shift lever 28 or the forward / reverse lever 59 is in the neutral position N
A neutral lamp 67 indicating that the operation is being performed is provided on the control unit. As shown in FIG. 3, a pressure sensor 74 is provided for detecting whether the operating pressure of the forward and reverse clutches 5, 6 has reached a predetermined pressure in the transmission state. Lamp 65,
66 is turned on.

[4] Next, the shift lever 28 is moved to the low speed position L.
The operation of the shift-up button 61 and the shift-down button 62 in the state where the user is operating at the high-speed position H will be described with reference to FIG. Forward / reverse lever 59
Is operated to the forward position F (step S1), an operation current is supplied to the solenoid operated valve 36b (step S1).
2), the switching valve 36a is operated to the supply side, the forward clutch 5 is operated to the transmission side, and the forward lamp 65 is turned on (step S3). When the forward / reverse lever 59 is operated to the reverse position R (step S1), an operation current is supplied to the electromagnetically operated valve 37b (step S4), the switching valve 37a is operated to the supply side, and the reverse clutch 6 is moved to the transmission side. , The reverse lamp 66 is turned on (step S5), and the buzzer 71
(See FIG. 2) operates intermittently (step S6).

When the forward / reverse lever 59 is operated to the neutral position N (step S1), the solenoid operated valves 36b and 37b are operated.
Operating current to the forward and reverse clutches 5,
6 is operated to the transmission interruption side (step S7), and the neutral lamp 67 is turned on (step S8). As described above, when both the forward and reverse clutches 5, 6 are operated to the transmission cutoff side, the power is cut off at the forward and reverse clutches 5, 6, and the aircraft stops.

As shown in FIG. 1, the first main transmission 10
Since the gears can be shifted to the second gear and the second main transmission 11 can be shifted to the second gear, the first and second main transmissions 10 and 11 can shift the gear to eight gears. In this case, the second main transmission 1
In a state where the first low speed clutch 26 is operated to the transmission side, the first to fourth speed clutches 21 to 2 of the first main transmission 10 are set.
4 corresponds to the first to fourth shift positions, and the first to fourth speed clutches of the first main transmission 10 are in a state where the high speed clutch 27 of the second main transmission 11 is operated on the transmission side. 21 to 24 correspond to fifth to eighth shift positions.

As shown in FIG. 3, the first to fourth speed clutch 2
1 to 24, each of the low and high speed clutches 26 and 27,
A pressure sensor 74 is provided for detecting whether or not the operating pressure has reached the operating pressures P1 and P2 in the transmission state. Based on the detection of the pressure sensor 74, the current first and second main transmissions 10 and 11 are provided. The shift position (1st to 8th speed) is detected, and the detected shift position is displayed on the shift display section 64 (step S9).

In the above state, it is assumed that the shift up button 61 or the shift down button 62 is pressed once (steps S10, S11). In this case, the solid line A in FIG.
1 (time point B1), the shift-up button 61
Is pressed, the operation current starts to be supplied to the solenoid operated valves 31b to 34b at the shift position one step higher than the current shift position, and conversely, when the shift down button 62 is pressed. The operation current starts to be supplied to the solenoid operated valves 31b to 34b at the shift position one step lower than the current shift position (step S12).

If the shift lever 28 is not in the neutral position N but in the low speed position L or the high speed position H (step S
13) At approximately the same time as step S12, as shown by the solid line A2 (time point B1) in FIG. 5, the electromagnetically proportional valves 38, 39 of the low-speed or high-speed clutches 26, 27 being operated on the transmission side are operated on the transmission side. Low speed or high speed clutch 2
The operating pressures 6 and 27 are reduced from the operating pressure P2 in the transmission state to a predetermined low pressure P3 (step S14). In this case, when operating from the fourth gear position to the fifth gear position, the operating pressure of the low speed clutch 26 is reduced to zero, and the operating pressure of the high speed clutch 27 is increased from zero to a predetermined low pressure P3. Conversely, when operating from the fifth gear position to the fourth gear position, the operating pressure of the high speed clutch 27 is reduced to zero, and the operating pressure of the low speed clutch 26 is reduced from zero to a predetermined low pressure P3.
Is operated.

The solid line A1 in FIG. 5 (from time B2 to time B3)
As shown in the figure, the operating pressures of the first-speed to fourth-speed clutches 21 to 24 at the first-stage high-speed side or the first-stage low-speed side are changed to the electromagnetically operated valves 31b to 34.
The pressure is increased to the operating pressure P1 in the transmission state by b. At the same time, the dashed line A3 in FIG. 5 (from time B2 to time B3)
As shown in the figure, the first to fourth speed clutches 21 to 21 before the shift-up button 61 or the shift-down button 62 is pressed.
24, the operating pressure is reduced from the operating pressure P1 in the transmission state to zero by the solenoid operated valves 31b to 34b (step S).
15).

If the shift lever 28 is operated to the low speed position L or the high speed position H instead of the neutral position N (step S
16) The operating pressure of the low-speed or high-speed clutches 26 and 27 maintained at the predetermined low pressure P3 is reduced to the solid line A2 (time point B) in FIG.
3 to time B4), the electromagnetic proportional valves 38, 39
, The operating pressure of the low-speed or high-speed clutches 26, 27 reaches the operating pressure P2 in the transmission state (step S17). In this case, from time B3 to time B4 of the solid line A2 in FIG.
6, 27 operating pressure boosting characteristics are set for each of the shift positions, and the operating pressure from time B3 to time B4 increases rapidly in a short time at a lower speed (first speed) shift position. Is done.

As described above, the shift up button 6
One operation by pressing the 1 or shift-down button 62 is ended, and when the operation is ended, the shifted position after the operation is displayed on the shift display section 64 (step S1).
8) The buzzer 71 operates only once, and the end of the operation is notified to the operator (step S19). The above operation is performed by the shift up button 61 or the shift down button 62.
Is not continuously performed even if is continuously pressed, and unless the shift-up button 61 or the shift-down button 62 is returned once and pressed again, the next one operation is not performed.

[5] Next, the shift lever 28 is moved to the neutral position N.
Shift up button 61
4 and the operation by the shift-down button 62.
It will be described based on. When the shift lever 28 is operated to the neutral position N, the sub-transmission 12 (shift member 53) (see FIG. 1) is operated to the neutral position, so that the aircraft is stopped. When the shift-up button 61 or the shift-down button 62 is pushed (steps S10 and S11) in a state where the shift lever 28 has been operated to the neutral position N, the first and the second are pushed in accordance with the pushing operation, as in the preceding paragraph [4]. The two main transmissions 10 and 11 are operated to the one-step high speed side or the one-step low speed side (steps S12 and S15), and the shift positions of the first and the first main transmissions 10 and 11 are displayed at each time of the operation. Is displayed (step S18), and the buzzer 71 operates only once (step S19).

In this case, since the machine is stopped, the low-speed and high-speed clutches 2 as in steps S14 and S17 are performed.
The depressurizing operation of the operating pressures 6 and 27 to the predetermined low pressure P3 and the raising operation to the operating pressure P2 in the transmission state are not performed (Steps S13 and S16). The above operation is not performed continuously even if the shift-up button 61 or the shift-down button 62 is kept pressed, and unless the shift-up button 61 or the shift-down button 62 is returned once and pressed again. The next one operation is not performed.

As described in the preceding paragraphs [4] and [5], the shift lever 28 is moved to the neutral position N, the low speed position L and the high speed position H.
Shift up button 61
By pressing the downshift button 62, the first and second main transmissions 10 and 11 can be operated to all shift positions (first to eighth speeds).

[6] Next, the shift operation of the subtransmission 12 by the shift lever 28 will be described. Shift lever 28
Is operated to the neutral position N, the auxiliary transmission 12 (shift member 53) is operated to the neutral position, and when the shift lever 28 is operated to the low speed position L, the auxiliary transmission 12 (shift member 5) is operated.
When 3) is operated to the low-speed position and the shift lever 28 is operated to the high-speed position H, the auxiliary transmission 12 (shift member 53) is operated to the high-speed position.

For example, when the forward / reverse lever 59 is operated to the forward position F (the forward clutch 5 is operated to the transmission side and the reverse clutch 6 is operated to the transmission cutoff side), the shift lever 28 is moved to the low speed position L (high speed). When the shift lever 28 is held at the low-speed position L (high-speed position H) by the operation button 57 and the lock pin 56 in a state where the lock button 56 is operated at the position H), the operation button 57 is pressed and operated.
Is operated from the guide plate 60, the solenoid operated valve 36b
As a result, the switching valve 36a is operated to the oil discharge side, and the forward clutch 5 is automatically operated to the transmission cutoff side.

Thus, the shift lever 28 is operated from the low-speed position L (high-speed position H) to the neutral position N and the high-speed position H (low-speed position L) while the operation button 57 is pressed.
When the operation button 57 is returned, the shift lever 28 is moved to the neutral position N, the high speed position H (the low speed position L) by the lock pin 56.
To hold.

In this case, when the operation button 57 is operated to return in the neutral position N, the switching valve 36a is operated to the supply side by the electromagnetic operation valve 36b, and the forward clutch 5 is automatically automatically moved to the transmission side immediately by the electromagnetic proportional valve 35. Operated. When the operation button 57 is operated to return in the high-speed position H (low-speed position L), the switching valve 36a is operated to the supply side by the electromagnetic operation valve 36b, and the forward clutch 5 is automatically automatically moved to the transmission side by the electromagnetic proportional valve 35. Is operated.

In a state where the forward / reverse lever 59 is operated to the reverse position R (a state where the reverse clutch 6 is operated on the transmission side and the forward clutch 5 is operated on the transmission cutoff side), the shift lever 28 is operated as described above. When the operation button 57 is pressed and returned, the reverse clutch 6 is automatically operated to the transmission blocking side and the transmission side as described above.

[7] Next, as described in the above item [4], the operating pressure of the low-speed or high-speed clutches 26, 27 is reduced to a predetermined low pressure P3.
The setting of the predetermined low pressure P3 when the pressure reducing operation is performed will be described. As shown in FIG. 2, there is provided a hand accelerator lever 9 capable of artificially setting the accelerator opening of the engine 1 to an arbitrary position, and a potentiometer type opening sensor 63 for detecting the operating position of the hand accelerator lever 9. Is provided, and a rotation speed sensor 68 for detecting the rotation speed of the engine 1 is provided. As shown in FIG. 6, when no load is applied to the engine 1 (the forward and reverse clutches 5 and 6 are operated to the transmission cutoff side and the PT
In the state where the O clutch 3 is operated to the transmission cutoff side),
The detection value of the rotation speed sensor 68 in the no-load state (the rotation speed N1 of the engine 1 in the no-load state) and the opening degree sensor 63
(The operation position of the hand accelerator lever 9) is obtained and stored as relation data C1.

Thus, in a state where the hand accelerator lever 9 is held at a certain operation position, the detection value of the opening degree sensor 63 (the operation position of the hand accelerator lever 9)
The detected value of the rotation speed sensor 68 in the no-load state corresponding to the above (the rotation speed N1 of the engine 1 in the no-load state) is obtained and stored based on the relation data C1 shown in FIG. Every time the operating position of the engine 9 changes, the detection value of the rotation speed sensor 68 in the no-load state (the engine 1 in the no-load state) corresponding to the detection value of the opening degree sensor 63 (the operating position of the hand accelerator lever 9) Rotation speed N
1) is determined and updated.

Next, the current rotational speed N2 of the engine 1 is detected by the rotational speed sensor 68, and the detected value of the rotational speed sensor 68 in the no-load state (the rotational speed N1 of the engine 1 in the no-load state) A rotation speed difference N3 from the current rotation speed N2 of the engine 1 is detected, and the first and second main transmissions 10,
11. The current shift position of the auxiliary transmission 12 (in [4] above, the shift position before the push-up button 61 and the shift-down button 62 are pressed) is detected.

At the low speed position of the auxiliary transmission 12, the first and second
The main transmissions 10, 11 correspond to the first to eighth shift positions, and the first and second main transmissions 10, 11 correspond to the ninth to sixteenth shift positions at the high speed position of the auxiliary transmission 12. Will be. As shown in FIG. 7, the rotational speed difference N3 and the engine 1
Is determined and stored as map data in advance based on the shift position. As a result, the load T applied to the engine 1 is obtained from FIG. 7 based on the rotational speed difference N3 and the current shift position, and based on the load T applied to the engine 1, a step S shown in FIG.
The predetermined low pressure P3 shown in FIG. 14 and the solid line A2 in FIG. 5 is set.

In this case, it is determined that the load T applied to the engine 1 is larger as the rotational speed difference N3 is larger, and the predetermined low pressure P3 shown by the solid line A2 in FIG. 5 is higher (the side closer to the operating pressure P2 in the transmission state). On the contrary, it is determined that the load T applied to the engine 1 is smaller as the rotational speed difference N3 is smaller, and the predetermined low pressure P3 shown by the solid line A2 in FIG. 5 is set to a lower value (zero side). . As shown in FIG. 7, the load T applied to the engine 1 is determined to be larger as the current shift position is on the lower speed side (first speed side), and the predetermined low pressure P3 indicated by the solid line A2 in FIG. The predetermined low pressure P3 is repeatedly set and updated as described above.

[8] As described in the preceding section [7] and FIG. 6, the detection value of the rotation speed sensor 68 in a no-load state corresponding to the detection value of the opening sensor 63 (the operation position of the hand accelerator lever 9). (Rotation speed N of engine 1 under no load condition)
In the case of determining 1), there is a deviation between the actual operation position of the hand accelerator lever 9 (actual accelerator opening of the engine 1) and the detection value of the opening sensor 63 due to secular change due to long-term use. May occur. next,
The correction of the relation data C1 when the above-described deviation occurs will be described with reference to FIG.

Whether the forward and reverse clutches 5, 6 are being operated to the transmission cutoff side (steps S21, S22)
Or, in a state where the shift lever 28 is operated to the neutral position N (step S23) (a state in which the body is stopped), P
In the state where the TO clutch 3 is operated to the transmission interruption side (step S24) (the state where the working device (not shown) provided in the machine body is stopped), the engine 1 is not loaded with the load T and no load is applied. State.

In the no-load state as described above, the detection value of the rotation speed sensor 68 (the current rotation speed N of the engine 1)
2) is lower than the set number of revolutions (for example, 950 rpm) (step S25), and the oil temperature of the mission oil in the transmission case 8 is higher than the set temperature (for example, 50 ° C.) (step S26), the timer counts down. It is started (step S27).

As a result, the detection value of the rotation speed sensor 68 (the current rotation speed N2 of the engine 1) is substantially constant (for example, the variation is within ± 15 rpm) (step S28), and the detection value of the opening sensor 63 is If the substantially constant state (step S29) is maintained for a set time (for example, 5 seconds) (step S30), the rotation speed sensor 68 at this time
(The current rotational speed N4 (N2) of the engine 1),
And the detection value D1 of the opening degree sensor 63 is taken in (steps S31, S32).

The value detected by the rotation speed sensor 68 (engine 1
If the relation data C1 deviates from the current rotation speed N4 (N2)) and the detection value D1 of the opening sensor 63,
The detection of the opening sensor 63 so that the relation data C1 shown in FIG. 6 corresponds to the detection value of the rotation speed sensor 68 (current rotation speed N4 (N2) of the engine 1) and the detection value D1 of the opening sensor 63. The data is translated in the value direction (the X direction in FIG. 6) (the left-right direction in FIG. 6) and the new relation data C2 is obtained.
Is updated to (step S33).

As described above, every time the conditions of steps S21 to S30 are satisfied, the detection value of the rotation speed sensor 68 (the current rotation speed N4 (N2) of the engine 1) and the detection value D1 of the opening degree sensor 63 Of data, related data C1
Is performed, and setting and updating of new relation data C2 and C3 are performed as shown in FIG.

[First Embodiment of the Invention] In the above-mentioned [Embodiment of the invention], steps S21 to S3 in FIG.
0, the new relation data C2, C
Instead of configuring so that setting and updating of 3 are performed, the following configuration may be adopted. The relational data C1 shown in FIG. 6 is stored in a first storage device (for example, an EEPROM), and based on the relational data C1 stored in the first storage device, step S14 in FIG. 4 and solid line A2 in FIG. A predetermined low pressure P3 is set. During this time, step S2 in FIG.
When the conditions of 1 to S30 are satisfied, new relation data C
2 and C3 are stored in the second storage device (for example, RAM), and every time the conditions of steps S21 to S30 in FIG. 8 are satisfied,
The relational data C2 and C3 stored in the second storage device are updated, and the relational data C2 and C3 stored in the second storage device are updated.
2, the predetermined low pressure P3 is not set based on C3.

When a main switch (not shown) is turned off, as in the case of ending a day's work or temporarily suspending the work, the related data C1 stored in the first storage device at this time is erased. And the related data C stored in the second storage device.
2 and C3 are stored in the first storage device. Thereafter, when the main switch is turned on and operated, the predetermined low pressure P3 shown in step S14 in FIG. 4 and the solid line A2 in FIG. 5 is generated based on the relation data C2 and C3 stored in the first storage device as described above. This is set in steps S21 to S3 in FIG.
Each time the condition of 0 is satisfied, the related data stored in the second storage device is updated.

[Second Alternative Embodiment of the Invention] In the aforementioned [Embodiment of the Invention] and [First Alternative Embodiment of the Invention], the auxiliary transmission 12 shown in FIG. Similarly, a low speed clutch (not shown) and a high speed clutch (not shown) of a hydraulic multi-disc type are arranged in parallel.
It may be configured to include an electromagnetic proportional valve (not shown). With this configuration, the first and second main transmissions 1
The shift positions of the 1st to 16th speeds are set by the 0, 11 and the auxiliary transmission 12, and the upshift button 61
By pressing the shift down button 62 and the first and second main transmissions 10 and 11, the sub transmission 1
2 is configured to be able to be operated to the first to 16th shift positions.

In the above [Embodiment of the invention] and [First alternative embodiment of the invention], the first and second embodiments shown in FIG.
The main transmissions 10 and 11 are of a hydraulic clutch type, but the first and second main transmissions 10 and 11 are gear transmission types in which a shift member (not shown) is slid in the same manner as the auxiliary transmission 12. And the shift member may be operated by sliding operation with a hydraulic cylinder (not shown). The first and second main transmissions 10, 11 are 1
The present invention can also be applied to a work vehicle configured to be able to shift to zero or six speeds. The present invention is also applicable to a work vehicle configured to be able to shift to three speeds of a high speed position, a medium speed position, and a low speed position. The present invention is applicable.

[0053]

According to the first aspect of the present invention, there is provided a rotation speed detecting means for detecting the rotation speed of the engine in the work vehicle, and an opening sensor for detecting the accelerator opening of the engine, so that no load is applied to the engine. When the relation data indicating the relation between the detection value of the rotation speed detection means and the detection value of the opening degree sensor in the load state is set, the relation data can be automatically corrected, so that the operator However, there is no need to artificially correct the related data, and the workability of the work vehicle can be improved.

According to the features of the first aspect, the present invention is intended for a state (a state in which the work traveling is temporarily stopped and the machine body and the working device are stopped) which can be said to almost always exist in a work vehicle in a day's work. The configuration in which the correction of the relational data is performed can prevent a situation in which the correction of the relational data is not forgotten and performed, thereby improving the functionality of the work vehicle. Was completed.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a transmission system of a transmission case.

FIG. 2 shows a shift up button and a shift down button,
Diagram showing the linked state of the shift lever and each part

FIG. 3 is a hydraulic circuit diagram of a forward and reverse clutch, first and second main transmissions, etc.

FIG. 4 is a diagram showing an operation flow when operating a forward / reverse lever, and an operation flow when pressing an upshift button and a downshift button.

FIG. 5 is a diagram showing a state of first to fourth speed clutches, low speed and high speed clutches when a shift up button and a shift down button are pressed.

FIG. 6 is a diagram showing relation data of a relation between a detection value of a rotation speed sensor in a no-load state (an engine rotation speed in a no-load state) and a detection value of an opening sensor

FIG. 7 is a diagram showing a relationship between a rotational speed difference between a value detected by a rotational speed sensor in a no-load state (engine rotational speed in a no-load state) and a current rotational speed of the engine, and a load applied to the engine;

FIG. 8 is a diagram showing a flow of operation when updating related data.

[Explanation of symbols]

 1 Engine 63 Opening sensor 68 Revolution detecting means C1, C2, C3 Related data

Claims (1)

[Claims] 1. An engine speed detecting means for detecting an engine speed, and an opening sensor for detecting an accelerator opening of the engine, wherein the engine speed is detected in a no-load state where no load is applied to the engine. Storage means for storing relationship data indicating the relationship between the detection value of the means and the detection value of the opening sensor, and the detection value of the rotation speed detection means in a no-load state is substantially constant and the opening sensor When the state in which the detection value is substantially constant is maintained only for a set time, the storage means based on the detection value of the rotation speed detection means and the detection value of the opening degree sensor in a no-load state at that time. An automatic correction structure for a work vehicle, comprising a correction means for automatically correcting the relation data stored in the work vehicle.