JP3159181B2 - Electronic shift device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic shift device, and is used for a moving vehicle such as a tractor.

[0002]

2. Description of the Related Art The applicant of the present invention has filed an electronic shift device in the past, and this electronic shift device is capable of shifting to an arbitrary position in response to an electric signal. A synchromesh type main transmission and an auxiliary transmission, and a hydraulic clutch for forward / reverse switching are provided immediately before these transmissions, and when a push button for a main transmission operation or a lever for an auxiliary transmission operation is operated, A shift clutch operated by hydraulic pressure is disengaged, a shifter operated by hydraulic pressure is moved to a target shift position, and then a hydraulic clutch is connected again to transmit power. .

[0003]

By the way, in the above-mentioned conventional apparatus, when the operator sets the number of gears, the gear shift position is stored even after the engine key switch is turned off. When the driver changes the speed or the same operator gets on the tractor at a later date, he does not know how fast the gear has been shifted up to that point, and when the shift position is on the high speed side, he engaged the engine and engaged the clutch. There was a risk that the aircraft would suddenly start immediately.

[0004]

[0005]

SUMMARY OF THE INVENTION In view of the above-mentioned problems, the present invention provides an electronic shift device as follows. That is, the rotational power of the engine via a transmission device for transmitting to the drive wheels, the gear position of the transmission in the electronic shifting device switched by operation of the actuator, the electronic
The shift device, after the engine is turned ON the engine key switch of the vehicle is started, when the shift position of the transmission by driving the actuator is set to the low speed side co
From this low-speed shift position,
Press the gear change switch to shift up
An electronic shift device comprising control means for shifting down .

[0006]

As described above, according to the present invention, after the engine key switch of the vehicle is turned on and the engine is started, the electronic shift device drives the actuator to lower the shift position of the transmission. And set it to
Since it is provided with control means for sequentially shifting up or down by pressing a speed-up or speed-down shift switch from the low-speed side shift position,
Stop the engine while the transmission is running at high speed,
There is no problem such as sudden start even when the engine is started next time, and since it shifts up or down sequentially from this low speed shift position, the vehicle speed after starting is prevented from suddenly increasing or decreasing. In addition, it can be safely operated by an unfamiliar person.

[0007]

[0008]

Embodiments of the present invention will be described below with reference to the embodiments shown in the drawings. First, the configuration will be described. Reference numeral 1 denotes a tractor, 2 denotes a front wheel, and 3 denotes a rear wheel. An engine 4 is mounted on the front of the tractor 1, and a clutch housing 6 containing a main clutch 5 and a transmission case 8 containing a transmission are connected to the rear of the engine 4. In the transmission case 8, a synchromesh type main transmission 9 capable of four-speed shifting, and a synchromesh type auxiliary transmission 10 capable of four-speed shifting are also provided. A forward / reverse switching device 11 of a hydraulic switching type is provided in series. The hydraulic clutch 13 of the forward / reverse switching device 11 includes a forward (F side) hydraulic clutch 13a and a reverse (R side) hydraulic clutch 13b. The combination of the main transmission 9 and the sub transmission 10 is configured so that the 16 speeds as shown in the table of FIG.

The arm portion of a single transmission lever 12 for operating the main transmission 9 and the auxiliary transmission 10 is a guide for an H-shaped transmission guide 15 beside the cockpit 14 as shown in FIGS. It is inserted into the groove 15a. A push button type shift switch 1 for speed increase is provided on a handle portion of the operation lever 12.
6 and a speed change switch 17 for deceleration are provided. For example, when the speed change switch 16 for speed increase is pressed, the gear is sequentially shifted up from the first speed to the fourth speed side. The transmission is downshifted from the first speed to the first speed, and thus the shift switches 16 and 17 are appropriately operated to operate the main transmission 9.
Is operated in the range of 1st to 4th speed.

The shift lever 12 can also switch the sub-transmission 10, but in this embodiment, when the sub-transmission 10 is switched, the clutch pedal 7 is depressed to disengage the main clutch 5 before shifting. It is composed. That is, after the main clutch 5 is disengaged, if the speed change lever 12 is moved back and forth or right and left along the speed change guide groove 15a, a high speed (L speed), a low speed (L speed), a medium speed (M speed), and an ultra low speed ( LL speed). The shift may be performed by disengaging the hydraulic clutch 13 of the forward / reverse switching device 11 instead of the main clutch 5. The movement of the speed change lever 12 is used for timing adjustment (step-up control) for connecting the clutch of the hydraulic clutch 13 and for monitor display.
Position detection sensors 20 and 21 for detecting the movement of the transmission case 8 are embedded in the lateral sides of the transmission case 8.

FIG. 3 shows the detailed structure. 2
The shifter pins 23 and 24 are pivotally supported at two upper and lower stages in the transmission case 8 along the front-rear direction.
Shifters 25 and 26 for switching the transmission gears are fitted and mounted, respectively. 27 and 28 are shifter pins 23 and 2
The upper surfaces of the protrusions 27 and 28 are cut out in a U-shape to form recesses 27a and 28a, and the spherical portion 12a at the lower end of the shift lever 12 is formed by the recesses. 27a and 28a are alternatively inserted. Then, the spherical portion 12 of the transmission lever 12 is recessed 27
a (or 28a), the shifter 25 (or 26) of the auxiliary transmission 10 is moved in the front-rear direction to perform a shift.

At this time, when the shifters 25 and 26 move in the front-rear direction, the cam 2 integrated with the shifters 25 and 26 is moved.
Reference numerals 5a and 26a depress the pins 20a and 21a of the position detection sensors 20 and 21 embedded in the wall of the transmission case 8 to detect a shift position. Specifically, the detection position is determined by the amount of movement of the pins 20a and 21a, the position detection sensor 20 detects each position of H speed-neutral (N) -L speed, and the position detection sensor 21 Each position of speed-neutral (N) -LL speed is detected. FIG. 4 is a cross-sectional view of a main part of the speed change operation unit viewed from the front.

As described above, in this embodiment, only the main speed change operation is performed with no clutch operation, and when the speed change switches 16 and 17 of the speed change lever 12 are pressed to change the main speed change device 9, the speed change is performed. First, the hydraulic clutch 13 of the forward / reverse switching device 11 is switched to the OFF state, and then the shifters 31 and 3 of the main transmission 9 are shifted.
Piston rod 3 as actuator for operating 2
The hydraulic clutch 13 of the forward / reverse switching device 11 is connected again when it is electrically detected that the shifters 31, 32 have reached the predetermined shift positions by forcibly moving the shifters 31, 32 in the longitudinal direction of the shaft by hydraulic pressure. You. These switching operations are all electrically controlled by a controller 35 described later.

FIG. 9 is a block diagram for explaining the relationship between the controller 35 constituting the control system, input means comprising sensors and switches, and output means such as a solenoid. The controller 35 includes the shifter 3 of the main transmission 9.
Solenoids 37, 38, 39, 40 for switching the solenoid valves 18, 19 for operating the first and second 32, solenoids 41, 42 of the solenoid valve 22 for switching the hydraulic clutch 13 of the forward / reverse switching device 11, and forward / backward switching device 11 is connected to a proportional solenoid 47 for controlling a proportional pressure reducing valve 45 for boost control. The proportional solenoid 47 controls the timing for connecting the hydraulic clutch 13 by changing the duty ratio of the pulse. Specifically, when the hydraulic clutch 13 is connected, as shown in FIG. 7, in the initial stage of the connection, in order to quickly move the piston to the target position, only one short time (50 to 100 msec as the initial time) is set.
A pulse current of 00% duty is applied, and then
The pressure is reduced and the duty ratio of the pulse is gradually increased in order to smoothly connect the clutch.

In FIG. 9, reference numeral 48 denotes a monitor lamp, and 49 denotes a position sensor for detecting the position of a shifter for operating the main transmission 9. The controller 35
A rotation sensor 52 for detecting the number of rotations of the engine 4;
Switch to a wheel rotation sensor 53 for detecting the number of rotations of the rear wheel 3, an FR switch 54 provided on the forward / reverse switching lever 30, a buzzer 55 as an alarm, and an inspection mode for checking the operating state of each sensor. A check switch 56 to be pressed at the time, a main key switch 57 for supplying power to each unit, and the like are connected.

In the controller 35, a program for issuing a shift command in conjunction with the operation of the key switch 57 is written in a storage means (not shown) together with a program for automatic shifting of the main transmission 9. ing. Hereinafter, this program will be described. In the flowchart shown in FIG. 10, first, in step S1, the state of each sensor and switch is read, and the key switch 57 is turned off.
Immediately after N (step S2), a command to excite the solenoid 37 for the first speed of the main transmission 9 is issued from the controller 35, and the first speed is selected (step S3). Therefore, no matter how fast the auxiliary transmission 10 is set, the main transmission 9 is switched to the low speed side, so that the aircraft does not start at high speed.

Thereafter, the operator operates the main transmission 9 to increase the speed of the switch 16 or the deceleration switch 1.
7, the main transmission 9 is switched within the range from the first speed to the fourth speed, and the auxiliary transmission 10 also operates the transmission lever 12 along the guide groove 15a of the H-type transmission guide 15. Thus, four-speed shifting can be performed in the range from H speed to LL speed. The control contents of the main shift operation and the sub-shift operation are defined in a subroutine of "shift change processing" in step S4. In addition to this control, a program is set such that when the auxiliary transmission 10 is operated, the main transmission 9 is also automatically switched. That is, when the auxiliary transmission 10 is switched from the high speed side to the low speed side,
The main transmission 9 immediately moves from the previous position to the fourth position.
The main transmission 9 is configured to shift down to the first speed when the speed is switched to the first speed and conversely, when the auxiliary transmission 10 is shifted up from the low speed side to the high speed side. These are controlled in accordance with the speed change table shown in FIG. 8, and are intended to prevent the vehicle speed from suddenly increasing or decreasing when the shift lever 12 is operated to switch the subtransmission device 10.

The "clutch pressure increasing process" shown in step S5 of the flowchart is a subroutine for gradually increasing the clutch pressure of the hydraulic clutch 13 to smoothly and quickly connect the clutch. As is apparent from the above embodiment, when the key switch 57 is turned on, a command to immediately set the main transmission 9 to the first speed is issued from the controller 35, so that the aircraft may move forward or backward at high speed. As a result, a safe electronic shift device was obtained. In this embodiment, when the key switch 57 is turned on, the main transmission 9 is set to the first position.
Although the transmission is switched to the low speed, the auxiliary transmission 10 may be switched to the low LL speed, or the main transmission 9 and the auxiliary transmission 10 may be switched to the low speed.

In this embodiment, the main transmission 9
And the auxiliary transmission 10 are operated by a single transmission lever 12, so that the number of operation levers is reduced as compared with the conventional transmission, and the number of parts is reduced, so that the configuration can be made inexpensively. . Next, FIGS. 11 and 12 will be described. In the above example, when the key switch 57 is turned on, the main transmission 9 is immediately set to the first speed.
When the work is temporarily interrupted and the work is performed again, it is often more efficient that the main transmission 9 is in the original shift position instead of the first speed. Therefore, this improved device is provided with a main transmission 9 when a long time has elapsed since the engine 4 was stopped.
Is switched to the first speed, and when the temporarily interrupted work is resumed, control is performed so as to maintain the original shift position. Components having the same configuration as in the block diagram of FIG. 9 are denoted by the same reference numerals, and different components are denoted by new reference numerals.

In FIG. 11, reference numeral 61 denotes a starter motor, 62 denotes a starter relay, 63 denotes a generator, and 64 denotes a battery. In FIG. 12, the controller 35 of the tractor 1 reads the state of switches and sensors (step # 1), and the operator turns the key switch 57
When the FF is set (step # 2), the controller 35 is immediately turned on.
The timer built in is activated (Step # 3),
At the same time, the current shift position is stored (step # 4).

When it is confirmed that a sufficient time has passed since the tractor 1 is stored in a warehouse or the like, the output command to the main transmission 9 is set to the first speed, and this is stored in the storage means ( Step # 6). At this time, when the engine 4 is stopped, an extra output command is issued from the controller 35, and the automatic output for the shift control is turned off so that the battery 64 is not discharged (step # 7).

On the other hand, to restart the temporarily stopped engine 4 during the operation, the key switch 57 is turned on. In this case, since the first speed is not written in the storage means as the output command to the main transmission 9, it is determined that the original shift command before the stop of the engine 4 is valid, and the shift position set by the operator is returned to the shift position. It is controlled (steps # 10, # 11, # 12).

As described above, according to the present invention, after the engine 4 is started by turning on the engine key switch 57 of the tractor 1, the main transmission
When the transmission is switched to the first speed by driving the gears 3 and 34 and the shift switch 16 for increasing the speed is pressed, the gear is sequentially shifted up from the low speed side to the high speed side, and the speed change switch 17 for speed reduction is provided.
When the engine is pressed, the engine 4 is shifted down sequentially from the high speed side to the low speed side. There is no problem of starting, and even an unfamiliar person can operate safely.

Further, since the driving timing of the piston rods 33 and 34 is driven after the engine key switch is turned on and the engine 4 is started, the hydraulic pump is operated only by the battery power source after stopping these hydraulic devices. This consumption can be reduced as much as possible in comparison with the driving method. 13 to 16 illustrate the proportional pressure reducing valve 45 for controlling the pressure of the hydraulic clutch 13 to increase. When pressure control is performed by changing the drive current of the proportional solenoid 47 by duty control, a drive frequency of about 100 Hz is normally used. At this time,
The pressure also fluctuates minutely at a cycle of 100 Hz. An averaging process is performed to equalize the fluctuation (2 to 3 kgf / cm2), and control is performed so that the averaged pressure becomes the set pressure. In this case, the pressure in the hydraulic clutch 13 is detected by the pressure sensor 70 connected to the hydraulic circuit. However, if the cycle of pressure fluctuation and the cycle of detection are the same, the same point (for example, point P in FIG. 14) is always used. Therefore, there is a problem that the pressure cannot be detected accurately because the pressure of the pressure is detected.

Therefore, here, 10 msec
The detection at the c interval is a half of the detection at the 5 msec interval. In order to make the average pressure accurate, it is preferable to further shorten the detection cycle and increase the average number.

[Brief description of the drawings]

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

FIG. 2 is a plan view of the tractor.

FIG. 3 is a diagram illustrating a relationship between a position detection sensor and a shifter of the auxiliary transmission.

FIG. 4 is a diagram illustrating a relationship between a shifter and a shift lever of the auxiliary transmission.

FIG. 5 is a power transmission diagram.

FIG. 6 is a hydraulic circuit diagram of a forward / reverse switching device and a main transmission.

FIG. 7 is a diagram illustrating a pattern of boost control.

FIG. 8 is a table illustrating the number of gear positions.

FIG. 9 is a control block diagram.

FIG. 10 is a control flowchart.

FIG. 11 is a block diagram of an improvement device.

FIG. 12 is a control flowchart of the improvement device.

FIG. 13 is a hydraulic circuit diagram of the improvement device.

FIG. 14 is a graph illustrating a state of a change in operating pressure of a hydraulic clutch.

FIG. 15 is a control flowchart.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Tractor 2 Front wheel 3 Rear wheel 4 Engine 9 Main transmission 10 Sub transmission 11 Forward / reverse switching device 12 Shift lever 33 Piston rod 34 Piston rod 35 Controller

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Hiroki Ono 1-Yachikura, Tobe-cho, Iyo-gun, Ehime Prefecture Inspector, Iseki Agricultural Machinery Co., Ltd. Examiner, Ichiro Kotani (56) Reference JP-A-2-182543 (JP, A) 55-52929 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) F16H 59/00-61/12 F16H 61/16-61/24 F16H 63/40-63 / 48

Claims (1)

(57) [Claims] 1. An electronic shift device for transmitting rotational power of an engine to drive wheels via a transmission and switching a shift position of the transmission by operating an actuator, wherein the electronic shift device includes an engine key of a vehicle. After the switch is turned on and the engine is started, the actuator is driven to shift the shift position of the transmission to the lower speed side.
And increase the speed from this lower gear position.
By pressing the speed change switch for
An electronic shift device comprising control means for shifting up or down .