JP3031810B2 - 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. When a synchromesh type main transmission and an auxiliary transmission, and a hydraulic clutch for forward / reverse switching are provided immediately before these transmissions and a push button for a main transmission operation or a lever for an auxiliary transmission operation is operated, The hydraulic clutch for forward / reverse switching is disengaged, and a shifter operated by hydraulic pressure is moved to a target shift position, and then the hydraulic clutch is connected again to transmit power. It is.

[0003]

By the way, in the above-mentioned conventional apparatus, when the operator sets the number of shift stages, the shift position is stored even after the key switch is turned off. If the operator changes or the same operator leaves the sun and gets on the tractor, it is not clear how fast the gear was shifted up to that point.
If the shift position is on the high speed side, there is a risk that the aircraft will suddenly start as soon as the engine is engaged and the clutch is engaged.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide an extremely safe electronic shift device. Therefore, the following technical measures were taken. That is, the main speed change device and thereby adapted gear position is obtained by the combination of the auxiliary transmission device, said main speed change device or auxiliary transmission device, the controller controls programming of power by the key switch ON is supplied
A control program for an electronic shift device configured to switch a solenoid valve based on a ram and to operate a hydraulic actuator to switch a shift position.
The, after the key Switch OFF, even in transmission what position switched by the hydraulic actuator, key - performs a shift command to the solenoid valve so as to obtain first-speed to the shift position and turns ON the switch An electronic shift device having a control flow .

[0005]

Embodiments of the present invention will be described below with reference to the embodiments shown in the drawings. First, the structure will be described.
Denotes a tractor, 2 denotes a front wheel, and 3 denotes a rear wheel. An engine 4 is mounted on a front part 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 a rear part 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.
And a hydraulic switching type forward / reverse switching device 11 for changing the traveling direction of the aircraft 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. Then, the combination of the main transmission 9 and the sub transmission 10 is configured so that the sixteen gears as shown in the table of FIG.

The arm of a single transmission lever 12 for operating the main transmission 9 and the auxiliary transmission 10 has an H-shaped transmission guide beside the cockpit 14 as shown in FIGS. It is inserted through 15 guide grooves 15a. A push button type speed change 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 switching the sub-transmission 10, the clutch pedal 7 is depressed to disengage the main clutch 5 before shifting. It is configured as follows. 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 a very low speed can be obtained. (LL speed) in four steps. 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 gearshift lever 12 is used for adjusting the timing of connecting the clutch of the hydraulic clutch 13 (step-up control) and for displaying a monitor.
Position detecting sensors 20 and 21 for detecting the movement are embedded in the lateral side of the mission case 8.

FIG. 3 shows the detailed structure. 2
The shifter pins 23, 24 are axially supported in two stages in the transmission case 8 so as to extend in 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 speed change lever 12 is formed as a protrusion. The recesses 27a and 28a are configured to be selectively 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 the speed change.

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 the 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 as viewed from the front.

As described above, in this embodiment, only the main speed change operation is performed by the no-clutch operation, and the speed change switches 16 and 17 of the speed change lever 12 are pressed to switch the main speed change device 9. 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
3 and 34 are forcibly moved in the longitudinal direction of the shaft by hydraulic pressure, and when it is electrically detected that the shifters 31 and 32 have reached a predetermined shift position, the hydraulic clutch 13 of the forward / reverse switching device 11 is connected again. Is done. These switching operations are all electrically controlled by a controller 35 described later.

FIG. 9 is a block diagram for explaining the relationship between a controller 35 constituting the control system, input means including sensors and switches, and output means such as a solenoid. The controller 35 includes a 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 of 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.
The pressure is reduced and the duty ratio of the pulse is gradually increased in order to connect the clutch smoothly.

In FIG. 9, reference numeral 48 is a monitor lamp, and 49 is a position sensor for detecting the position of a shifter for operating the main transmission 9. In addition, this controller 35
A rotation sensor 52 for detecting the number of rotations of the engine 4;
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 module for confirming the operation state of each sensor. A check switch 56 to be pressed when switching to the negative mode, a main key switch 57 for supplying power to each unit, and the like are connected.

The controller 35 stores, in its storage means (not shown), a program for issuing a shift command in conjunction with the operation of the key switch 57 together with a program for automatic shifting of the main transmission 9. Has been written to. Hereinafter, this program will be described. In the flowchart shown in FIG. 10, first, the state of each sensor and switch is read in step S1, 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.
By operating the gear 7, the main transmission 9 is switched within the range of the first to fourth speeds, 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 main speed change operation and the sub speed change operation are subroutines of the "shift change process" of step S4.
The contents of control are defined by the chin. 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 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. It is. As is clear from the above embodiment, when the key switch 57 is turned ON, the command to immediately set the main transmission 9 to the first speed is issued from the controller 35, so that the aircraft moves forward or backward at high speed. The result is a safe electronic shift device. 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 the single transmission lever 12, so that the number of operation levers is smaller than that of the conventional transmission. Therefore, there is a feature that it can be configured at a lower cost as the number of parts is reduced. Next, FIGS. 11 and 12 will be described. In the above example, when the key switch 57 is turned on,
Although the main transmission 9 is immediately shifted to the first speed, it is more efficient if the main transmission 9 is in the original shift position instead of the first speed when the operation is temporarily interrupted and the operation is performed again. There are many. Therefore, this improved device has the engine 4
The main transmission 9 is switched to the first speed when a long time elapses after stopping, and control is performed to maintain the original shift position when the temporarily interrupted work is resumed. . 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.
, 62 is a starter relay, 63 is a generator, and 64 is a battery. In FIG. 12, first, the state of switches and sensors is read (step # 1), and when the operator turns off the key switch 57 of the tractor 1 (step # 2), it is immediately incorporated into the controller 35. The timer operates (step # 3), and at the same time, the current shift position is stored (step # 4). When it is confirmed that a sufficient time has elapsed after storing the tractor 1 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,
The automatic output for the speed change control is turned off so that an extra output command is issued from the controller 35 and the battery 64 is not discharged (step # 7). On the other hand, when the engine 4 stopped during the operation is restarted, the key switch 57 is turned ON. In this case, since the first speed is not written in the storage means as an output command to the main transmission 9, the original shift command before the engine 4 was stopped is determined to be valid, and the shift set by the operator is set. The position is controlled (steps # 10, # 11, # 12).

FIGS. 13 to 16 illustrate the proportional pressure reducing valve 45 for controlling the pressure of the hydraulic clutch 13 to increase the pressure. 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 is 100
The frequency fluctuates minutely at the frequency of Hz, and the fluctuation (2 to 3 kg
f / cm ² ), an averaging process is performed, 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, in this improved example, the conventional 10
What was detected at msec intervals is half of that of 5 msec
c interval. In order to make the average pressure accurate, it is preferable to further shorten the detection cycle and increase the average number.

[0021]

As described above, the present invention is configured so that the gear stage can be obtained by a combination of the main transmission and the auxiliary transmission, and the main transmission or the auxiliary transmission is supplied with power by turning on a key switch. controller, which is the
In an electronic shift device configured to switch an electromagnetic valve based on a control program and to operate a hydraulic actuator to switch a shift position , control of the electronic shift device is performed.
In the program, after the key switch is turned off, the shift position is changed to the first speed when the key switch is turned on, regardless of the position of the transmission that is switched by the hydraulic actuator.
Control flow that performs a shift command to the solenoid valve so as to obtain
Since it is an electronic shifting device characterized by having an over, for example, when multiplied by the vehicle engine has been stopped the shift position remains fast, the transmission is switched to the state of the first speed vehicle There is no problem that the vehicle starts at high speed, and even an unfamiliar person can operate safely.

[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 20 Sub transmission position detection sensor 21 Sub transmission position detection sensor

──────────────────────────────────────────────────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) Actually Open Hei 3-62261 (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. A gear ratio is obtained by a combination of a main transmission and a subtransmission, and the main transmission or the subtransmission is controlled by a controller supplied with power by a key switch ON to a control program. Based
In the electronic shift device configured to switch the electromagnetic valve by operating the hydraulic actuator to switch the shift position, the control program of the electronic shift device includes a shift device that is switched by the hydraulic actuator after the key switch is turned off. No matter where you are, turn on the key switch
Wherein the electronic shift device has a control flow for issuing a shift command to the solenoid valve to set the shift position to the first speed .