JP3449331B2 - Transmission - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmission controlled by a microcomputer , and more particularly to control during shift change.

[0002]

2. Description of the Related Art The applicant of the present invention has used a microcomputer-controlled variable
A speed device, a so-called electronic shift device, has been filed, but this electronic shift device is capable of shifting to an arbitrary position in accordance with an electric signal, and specifically, is a synchromesh type main transmission device. An auxiliary transmission, and a hydraulic clutch for switching between forward and backward movements are provided immediately in front of these transmissions, and the turning base of the operation lever for switching the auxiliary transmission detects the operator's intention to shift. A shift sensor for detecting the shift position and a position sensor for detecting the shift position of the auxiliary transmission are provided. When a shift operation is performed by the operating lever, first, the shift sensor operates to disconnect the hydraulic clutch, and then the operating lever. After the sub transmission is switched by, the shifter of the main transmission that operates hydraulically,
It is configured to output a shift output.

[0003]

By the way, in the conventional device as described above, the operating lever is operated to switch one transmission, but at this time, the vehicle speed changes greatly and the vehicle suddenly starts moving. Alternatively, there was a problem of sudden deceleration. On the other hand, when the operating lever is temporarily operated to the neutral position to stop or decelerate the vehicle and then shift again, it is desirable to return to the original vehicle speed without performing the shift operation as much as possible.

[0004]

SUMMARY OF THE INVENTION The present invention is proposed in view of the above problems, and a transmission of a vehicle is constructed as follows.

That is, the first transmission 10 for switching by the turning operation of the operating lever 12, the actuator 16,
And a second transmission 9 that is switched through the operation of 16 to change the shift position of each of the transmissions 10 and 9 to a sensor 40,
The rewritable storage at detecting and storing means by 41, when the first change gear unit 10 by the operation lever 12 is switched to the high-speed side, the second transmission 9 switched to the low speed side by the actuator 16, 16, and When the first transmission 10 is switched to the low speed side by the operation lever 12, the second transmission 9 is switched to the high speed side by the actuators 16 and 16, and the operation lever 12 is further moved.
When the operation is interrupted in the middle despite being operated, the shift position of the second transmission 9 is not changed and stored in the storage means.
Providing the control unit 18 to make maintaining the shift position before the lever operation being set to shift apparatus according to claim. Also,
Was transmission according to claim 1, characterized in that the arrangement for switching the second speed change device 9 by a button switch 14 provided on the grip portion of the operating lever 12.

[0006]

Embodiments of the present invention will be described below based on the embodiments shown in the drawings. First, the structure will be explained as follows.
Is a tractor, 2 is a front wheel, and 3 is a rear wheel. An engine 4 is mounted on the front part of the body of the tractor, and a clutch housing 6 accommodating a main clutch 5 and a transmission case 8 accommodating a transmission are connected to the rear part of the engine 4. Inside the mission case 8, a main transmission 9 which is a second transmission capable of shifting four speeds, and an auxiliary transmission 10 which is also a first transmission capable of shifting four speeds,
A forward / reverse switching device 11 that changes the traveling direction of the machine body is provided in series.

A button type speed change switch 14 for speed increase / decrease is provided at the handle portion of the speed change lever 12, and the main speed change device 9 is switched from the first speed to the fourth speed by operating the switch. The shift lever 12 is configured to be swingable in the front-rear direction and the left-right direction about two axes in the front-rear direction and the left-right direction. When the shift lever 12 is tilted outward in the lateral direction, the shift-sensing sensor 15 is turned on and the hydraulic clutch is disengaged. If the speed change lever 12 is swung back and forth while maintaining this state, the auxiliary speed change device 10 mechanically shifts to the L level.
Switching is possible within the range of four speeds of L, L, M, and H.

The main transmission 9 and the sub transmission 10 are both composed of a synchromesh type transmission, and only the forward / reverse switching device 11 is composed of a hydraulic clutch. When the main transmission 9 is switched, first, the hydraulic clutch of the forward / reverse switching device 11 is switched to OFF, and then the piston rod 1 for operating the shifter of the main transmission 9.
6 is forcibly moved in the axial longitudinal direction by hydraulic pressure, and when the shifter (not shown) reaches a predetermined shift position, the hydraulic clutch of the forward / reverse switching device 11 is connected again. In addition, all of these switching are electrically controlled.

FIG. 2 is a block diagram of the control device. The control unit 18 including a microcomputer includes solenoids 20, 21, 22, 23 for switching the main transmission device 9 and a forward / reverse switching device 11 for switching. Solenoids 25, 26 for use with the solenoid 30 and a solenoid 30 for controlling the boost control valve 28 of the forward / reverse switching device 11 are connected. Solenoids 20 and 21,
22 and 23 are paired respectively, and the former is 1st-2.
The switching valve 24 for the speed is controlled, and the latter controls the switching valve 27 for the third speed and the fourth speed.

Reference numeral 32 is a monitor lamp for displaying the shift position. Further, the control unit 18 includes a rotation sensor 34 for detecting the rotation speed of the engine 4, a wheel rotation sensor 35 for detecting the rotation speed of the rear wheels 3, and an FR switching switch 38 provided on the forward / reverse switching lever 37. , A main shift position sensor 4 for detecting the positions of shifters of the main transmission 9 and the sub transmission 11
0, the auxiliary shift position sensor 41, the shift switch 14, the shift detection sensor 15 and the like are connected.

FIG. 3 is a hydraulic circuit diagram showing the piping configuration of the entire hydraulic equipment provided in the tractor 1. Briefly describing the entire circuit configuration, the hydraulic oil sent from the main pump 45 flows into a sub control valve 46 for taking out an external hydraulic pressure, and a part of it enters a valve 48 for horizontal control via a diversion valve 47. The horizontal cylinder 49 is controlled to expand and contract. Then, the remaining hydraulic oil divided by the diversion valve 47 flows into the valve 50 for controlling the working machine lifting and is fed into the main cylinder 51, and the lift arm 52 is rotated to raise and lower the working machine. ing.

A sub-pump 55, which is independent of the main pump 45, is connected to a pressure reducing valve 57 for taking out hydraulic oil of a constant pressure, and a power steering device 59 is used by utilizing the hydraulic oil kept at a constant pressure. , Forward / reverse switching device 1
1, PTO clutch control device 60, front wheel speed control device 6
2. The electronic shift device 64 is operated. The PTO clutch control device 60 includes a PTO clutch 66 and a valve 67 that connects and disconnects the PTO clutch 66, and the front wheel speed control device 62 includes a hydraulic clutch 69 and a valve 70. The front wheel speed control device 62 includes a mode selector switch (not shown) and the front wheel 2
Is connected to a sensor that detects the turning angle of the front wheel 2 and the standard four-wheel drive state in which the speed of the front wheel 2 is substantially the same as that of the rear wheel 3.
It is configured to be able to switch to the front wheel double speed drive state in which the peripheral speed of the rear wheel 3 is increased more than that of the rear wheel 3 or the full time drive state in which 2WD or 4WD is automatically selected according to the slip state of the rear wheel 3. is doing.

FIG. 6 shows the number of shift stages of the transmission described in this embodiment, and shows the relationship between the main shift and the sub shift from the low speed first stage to the high speed 16th stage. There is. In addition, in the memory in the control unit 18, the transmission lever 1
A program is set such that when the sub transmission 10 is operated by using 2, the main transmission 9 is also shifted at the same time.

Specifically, when the auxiliary transmission 10 is accelerated by one stage (for example, M speed is changed to H speed), the main transmission 9 is at the lowest speed position (for example, 4 speeds) from the current shift position.
Downshifting from first speed, third speed, second speed to first speed) and conversely decelerating the auxiliary transmission 10 by one stage (for example, changing from M speed to L speed).
When operated, the main transmission 9 is configured to shift up from the current shift position to the highest speed position (for example, 1st speed, 2nd speed, 3rd speed to 4th speed).

By the way, if such a program is adopted, when the operator grips the gear shift lever 12 to perform a shift operation, the gear shift lever passes over the target position, or the gear shift lever 12 is moved laterally in order to shift gears. Despite having pushed it outward, a problem occurs when the intention changes again and the gear shifting operation is stopped.
After all, in such a case, the main transmission 9 may be shifted to a shift position different from one's will.

For example, the current shift position is the auxiliary transmission 1.
When 0 is the M speed and the main transmission 9 is the 1st speed (gear speed; 9 speeds), the speed change lever 12 is moved to the deceleration side and the auxiliary transmission 1
When the operator intends to set 0 to the L speed but moves to the LL speed, and the operator returns the speed change lever 12 to the L speed in order to correct the overshoot, the main transmission 9 shifts to the 1st speed instead of the 4th speed (shift speed: 8 speed). The vehicle will be shifted to a high speed (gear speed: 5 speeds). The operator operates the sub speed L speed and the main speed 4 speed (gear stage;
Although 8 speeds are expected, the main gear shift is 1st speed, which means that the vehicle speed is significantly reduced, resulting in a problem that work efficiency is significantly reduced.

Therefore, the following program is set in the memory of the control unit 18 of the electronic shift device 64 so as not to cause such a problem. In addition,
A control program of the present invention for temporarily holding the main transmission 9 in the neutral state during the shift operation of the sub transmission 10 will also be described. The flow chart shown in FIG. 4 is the control program, and first, the states of various sensors and switches connected to the control unit 18 are read (step S1). Gear shift lever 1 for the operator to shift gears
Shift sensor 15 turns on when gripping 2 and tilting it laterally outward
(Step S2). This shift detection sensor 15 is O
Immediately after the shift to N, it is determined whether or not the main shift position sensor (main shift sensor) 40 is in the neutral state (steps S3 and S4). If it is not in the neutral state, the sub shift position sensor (sub shift sensor) 41. The detected position of the main shift position sensor 40 is stored in the memory (steps S5 and S6).
Then, the solenoids 20, 21, 22, 23 are turned off to return the piston rod 16 of the main transmission 9 to the neutral position.
An output command to set is set (step S7).

On the other hand, when the shift lever 12 is moved in the front-rear direction to switch the sub-transmission device 10 and the shift lever 12 is returned to the inner lateral direction again, the shift detection sensor 15 is immediately switched from ON to OFF (step S9). At this time, if the shift lever 12 is operated in the upshifting direction, the main transmission 9 is changed to the first speed (step S11),
On the contrary, if it is operated in the downshifting direction, a command for setting the main transmission 9 to the fourth speed is set.

The shift detection sensor 15 is once turned on and then turned off.
In other words, even if the operator selects
When the operator tries to shift the gear once by grasping 2, the shift position of the main transmission 9 does not change at all and the stored value up to that point is set (step S14). Then, the shift operation of the main transmission 9 is performed by the control unit 18 based on these set commands (step S8).

When switching between the transmissions 9 and 10, first, the forward / reverse switching device 11 which also serves as a hydraulic clutch is set to a neutral state, and after the shift is completed, the forward / reverse switching device 11 is connected again, and the boost control valve 28 is operated. Solenoid 3
A current is applied to 0 and the clutch is gradually connected. These series of operations are performed in accordance with commands from the control unit 18, and the piston rod 16 of the main transmission 9 is moved back and forth to shift gears.

FIG. 5 shows the timing at which the main transmission 9 and the sub transmission 10 are switched by operating the transmission lever 12 in the front-rear direction. Briefly, when the shift lever 12 is tilted sideways and the shift detection sensor 15 is turned on,
The hydraulic clutch of the forward / reverse switching device 11 is returned to neutral, and the boost control of the boost control valve 28 is stopped at the same time.

During this period, the speed change lever 12 is in the M speed, the L speed, and the L speed.
Although it returns to the L speed again via the L speed, the main transmission 9 enters the 4th speed without entering the 1st speed, and when the main speed change position sensor 40 confirms that, the boost control works again and the forward / rearward movement is performed. The hydraulic clutch of the switching device 11 is gradually connected.

[0023]

As described above, according to the present invention, the operating lever 12 is used.
Is provided with a first transmission device 10 that is switched by a turning operation of the actuators and a second transmission device 9 that is switched by the operation of actuators 16 and 16, and the transmission position of each of the transmission devices 10 and 9 is changed.
Position is detected by the sensors 40 and 41 and stored in the storage means.
To Rutotomoni, the first change gear unit by the operation lever 12 1
When 0 is switched to the high speed side, the second transmission 9 is switched to the low speed side by the actuators 16 and 16,
Moreover, when the first transmission 10 is switched to the low speed side by the operation lever 12, the actuators 16, 1
A second transmission 9 because those switching to the high speed side by 6, while switching the one of the transmission 10 by operating the operating lever, the other of the transmission 9, since it is switched to low direction of change of the vehicle speed You can shift without sudden acceleration and deceleration. In addition, despite operating the lever,
When it is interrupted in the shift position of the second transmission 9
Remains unchanged, before lever operation stored in the storage means
Since the gear shift position is maintained, the operator can improve the operability of the vehicle without performing an unnecessary gear shift operation when the operator makes a mistake or is confused about the gear shift operation.

[Brief description of drawings]

FIG. 1 is an overall side view of a tractor.

FIG. 2 is a block diagram showing a control system.

FIG. 3 is a hydraulic circuit diagram.

FIG. 4 is a flowchart showing the contents of a control program.

FIG. 5 is a time chart showing how control is performed.

FIG. 6 is a table explaining the number of shift stages.

[Explanation of symbols]

1 tractor 2 front wheels 3 rear wheels 4 engine 9 Main transmission 10 Auxiliary transmission 11 Forward / reverse switching device 12 shift lever 18 Control unit

Claims (2)

(57) [Claims] 1. A first transmission device 10 which is switched by a turning operation of an operating lever 12, and actuators 16, 16.
It provided a second transmission 9 for switching over the operation, prior to
The shift positions of the transmissions 10 and 9 are set to the sensors 40 and 41.
The rewritable memory at more detected and stored means, when the first change gear unit 10 by the operation lever 12 is switched to the high-speed side, switching the second transmission 9 to the low speed side by the actuator 16, 16, and the Operating lever 12
When the first transmission device 10 is switched to the low speed side by the above, the second transmission device 9 is switched to the high speed side by the actuators 16 and 16, and the operation lever 12 is further operated.
However, if the operation is interrupted halfway, the gear shift position of the second transmission 9 is not changed and stored in the storage means.
Make maintaining the shift position of the front lever has a control unit 18
A transmission that is provided with. 2. The second transmission 9 is connected to the operating lever 1
2. The variation according to claim 1, wherein the button type switch 14 provided on the second grip portion is used for switching.
Speed equipment.