JP3448878B2 - Powered vehicle transmission - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention, change in response to the electrical signal
The present invention relates to a speed change transmission , and more particularly to control when a shift is changed. 2. Description of the Related Art The present applicant has received electric signals in the past to change gears.
Has filed an application for a transmission in which
When an operator designates a shift position, a shift is made to a predetermined position in accordance with an electric signal. Specifically, a synchromesh type main transmission and an auxiliary transmission, and immediately before these transmissions, A hydraulic clutch for switching between forward and reverse is provided, and at the base of rotation of an operation lever for switching the sub-transmission, a shift sensing sensor for detecting the intention of the operator as to whether or not to shift, and a sub-transmission. When a shift operation is performed by the operation lever, the shift sensor is first operated to disengage the hydraulic clutch, and then the sub-transmission is switched by the operation lever. After that, the shift output is output to the shifter of the main transmission that is operated by hydraulic pressure. [0003] In the above-described conventional apparatus, when shifting is performed using the operation lever, first, when the auxiliary transmission is switched, it is determined that the auxiliary transmission is switched. A shift output for shifting up or down the shifter of the main transmission is detected by a sensor, and then a shift completion operation is delayed, resulting in a poor operation feeling. There was a point. SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and immediately after a shift operation of a subtransmission is performed, a shift actuator of a main transmission is set to a neutral position. The shift operation is completed quickly. For this reason,
The present invention has taken the following technical measures. That is, the main transmission 9 capable of shifting in a plurality of stages.
, An auxiliary transmission 10, and a forward / reverse switching device 11,
The transmission 10 is operated by operating the operation lever 12 in the front-rear direction.
Instead, the main transmission 9 is provided with a shift switch provided on the operation lever 12.
Powered vehicle configured to switch by operating switch 14
At this time, a shift position is detected at the base of the operation lever 12.
The sub-shift position sensor 41 is provided, and
As soon as the sub-shift operation is started, the main transmission 9 is turned off.
The auxiliary transmission 10 is held at the neutral position from time to time.
When operated to the speed increasing side, the main transmission 9 is switched to the speed reducing side,
When the auxiliary transmission 10 is switched to the reduction side, the main transmission 9
A control unit 18 for switching the speed to the speed increasing side.
The configuration of the transmission of the power vehicle is described below. [0006] [Embodiment] Hereinafter, with reference to the drawings, an embodiment of the present invention. First, the structure 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, 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 main transmission 9 capable of four-speed shifting and an auxiliary transmission 1 capable of four-speed shifting are also provided.
0, forward / reverse switching device 1 for changing the direction in which the aircraft advances
1 are provided in series. A button-type speed change switch 14 for increasing or decreasing the speed is provided on a handle portion of the speed change lever 12, and is operated to switch the main transmission 9 from the first speed to the fourth speed. The shift lever 12 is configured to be swingable in the front-rear direction and the left-right direction about two axes of the front-rear direction and the left-right direction. When the transmission lever 12 is swung back and forth while maintaining this state, the auxiliary transmission 10
The speed can be switched in the range of L, L, M, and H speeds. The main transmission 9 and the auxiliary transmission 10 are both constituted by a synchromesh transmission, and only the forward / reverse switching device 11 is constituted by a hydraulic clutch. When the main transmission 9 is switched, first, the hydraulic clutch of the forward / reverse switching device 11 is switched off, and then the piston rod 1 that operates the shifter of the main transmission 9
When the shifter 6 (not shown) reaches a predetermined shift position, the hydraulic clutch of the forward / reverse switching device 11 is connected again. Note that all of these switchings are electrically controlled. FIG. 2 is a block diagram of the control unit. The control unit 18 comprising a microcomputer includes solenoids 20, 21, 22, and 23 for switching the main transmission unit 9, and a switching unit for switching the forward / reverse switching unit 11. Solenoids 25 and 26 and a solenoid 30 for controlling the boost control valve 28 of the forward / reverse switching device 11 are connected. Solenoids 20 and 21,
And 22 and 23 are paired, the former being the first gear
The switching valve 24 for the third speed is controlled, and the latter controls the switching valve 27 for the third and fourth speeds. Reference numeral 32 denotes a monitor lamp for displaying a shift position. 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 wheel 3, and an FR switch provided on a forward / reverse switching lever 37. 38, a main transmission position sensor 4 for detecting the positions of the shifters of the main transmission 9 and the auxiliary transmission 11.
0, an auxiliary shift position sensor 41, a shift switch 14, a shift sensing sensor 15, and the like. FIG. 3 is a hydraulic circuit diagram showing a piping configuration of the entire hydraulic equipment provided in the tractor-1. In brief, the entire circuit configuration will be described. Hydraulic oil sent from the main pump 45 flows into a sub-con valve 46 for taking out the external hydraulic pressure, and a part of the oil enters a horizontal control valve 48 via a diversion valve 47. The expansion and contraction of the horizontal cylinder 49 is controlled. The remaining hydraulic oil diverted by the diverting valve 47 flows into the work machine lift control valve 50 and is sent to the main cylinder 51, and the lift arm 52 is rotated to raise and lower the work machine. are doing. A sub-pump 55 independent of the main pump 45 is connected to a pressure reducing valve 57 for taking out hydraulic oil at a constant pressure, and a power steering device utilizing the hydraulic oil maintained at a constant pressure. 59, 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 switches the PTO clutch 66 on and off. 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 change switch (not shown) and a front wheel 2 (not shown).
A standard four-wheel drive state in which the speed of the front wheel 2 is made substantially the same as that of the rear wheel 3,
The driving speed can be switched between a front wheel double speed driving state in which the peripheral speed of the rear wheel 3 is increased than that of the rear wheel 3 or a full time driving state in which the 2WD or 4WD is automatically selected according to the slip state of the rear wheel 3. are 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 first low speed to the sixteenth high speed. I have. The memory in the control unit 18 includes a gearshift lever-1.
A program is set such that when the sub-transmission 10 is operated using the second transmission 2, the main transmission 9 is also shifted at the same time. More specifically, when the auxiliary transmission 10 is increased by one speed (for example, changed from the M speed to the H speed), the main transmission 9 is moved from the current shift position to the lowest speed position (for example, 4 speed).
, 3rd gear, 2nd gear to 1st gear), and conversely, the auxiliary transmission 10 is reduced by one gear (for example, change from M gear to L gear)
When this is done, the main transmission 9 is configured to shift up from the current shift position to the highest speed position (eg, 1st, 2nd, 3rd to 4th). By the way, when such a program is adopted, when the operator grips the shift lever 12 and performs a shift operation, the shift lever passes over a target position or the gear is shifted to shift. Despite the lever 12 being tilted laterally outward, a problem occurs when the intention changes again halfway and the shifting operation is stopped,
Eventually, in such a case, the main transmission 9 may be shifted to a shift position different from its own will. For example, when the current shift position is the subtransmission 1
When 0 is the M speed and the main transmission 9 is the 1st speed (gear speed: 9 speeds), the shift lever 12 is moved to the deceleration side and the subtransmission 1
When the operator intends to change the 0 to the L speed and moves to the LL speed, and the operator returns the shift lever 12 to the L speed in order to correct the overshoot, the main transmission 9 is in the 4th speed (8th speed). Instead, the gear is shifted to the first speed (gear position: five speeds). The operator operates the sub-shift L speed and the main shift 4 speed (gear position;
(8th gear) is expected, but the main speed is 1st, so the vehicle speed is greatly reduced, causing a problem that the working 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 that such a problem does not occur. In addition,
A control program according to the present invention for temporarily maintaining the main transmission 9 in the neutral state during the shifting operation of the sub-transmission 10 will also be described. The flowchart shown in FIG. 4 is the control program. First, the states of various sensors and switches connected to the control unit 18 are read (step S1). Shift lever-1 so that the operator can shift
Shift detection sensor 15 is turned on when gripping 2 and tilting laterally outward
(Step S2). This shift sensing sensor 15 is
Immediately after it becomes N, it is determined whether or not the main shift position sensor (main shift sensor) 40 is in a neutral state (steps S3 and S4). And the detected position of the main shift position sensor 40 are stored in the memory (steps S5 and S6).
Next, the solenoids 20, 21, 22, and 23 are turned off to return the piston rod 16 of the main transmission 9 to the neutral position.
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 when the shift lever 12 is returned to the inside side again, the shift sensor 15 is immediately switched from ON to OFF (step S9). . At this time, if the shift lever 12 is operated in the direction of shifting up, the main transmission 9 is changed to the first speed (step S11),
On the other hand, if the operation is performed in the downshift direction, a command to set the main transmission 9 to the fourth speed is set. The shift sensing sensor 15 is once turned off from on.
In other words, the operator changes the gearshift lever-1
If an attempt is made to shift the gear once while grasping the position 2, the shift position of the main transmission 9 is not changed 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, 10, the forward / reverse switching device 11, which also functions as a hydraulic clutch, is set to a neutral state. After the shift is completed, the forward / reverse switching device 11 is connected again. Solenoid 3
Current flows to 0, and the clutch is gradually connected. These series of operations are performed according to a command from the control unit 18, and the piston rod 16 of the main transmission 9 is moved back and forth to perform a shift. FIG. 5 shows the timing at which the main transmission 9 and the auxiliary transmission 10 are switched by operating the transmission lever 12 in the front-rear direction. Briefly speaking, the gearshift lever
When the shift detection sensor 15 is turned on by tilting the side 12
The hydraulic clutch of the forward / reverse switching device 11 is returned to neutral, and at the same time, the boost control of the boost control valve 28 is stopped. During this time, the transmission lever 12 is operated at the M speed, the L speed, and the L speed.
After returning to the L speed again via the L speed, the main transmission 9 enters the 4th speed without entering the 1st speed, and when it is confirmed by the main speed change position sensor 40, the boost control is activated again, and The hydraulic clutch of the switching device 11 is gradually connected. According to the present invention, as described above, a plurality of speeds can be changed.
Possible main transmission 9 and auxiliary transmission 10, and forward / reverse switching
The auxiliary transmission 10 is provided with an operating lever 12 in front.
The main transmission 9 is operated by moving the operating lever 1 backward.
2 by operating the speed change switch 14 provided in
In the configured powered vehicle, a base of the operation lever 12 is provided.
The auxiliary shift position sensor 41 for detecting the shift position is provided in
Immediately after the sub-shift operation by the operating lever 12 is started
When the main transmission 9 is temporarily held at the neutral position,
When the auxiliary transmission 10 is operated to the speed increasing side, the main transmission
9 is switched to the reduction side, and the auxiliary transmission 10 is switched to the reduction side.
When the control unit 18 switches the main transmission 9 to the speed increasing side,
Since the operating lever 12 is moved in the front-rear direction to switch the sub-transmission 10, the main transmission 9 is provided.
Will also be forced back into the neutral position, further operation les
It is only necessary to move the main transmission 9 from the neutral position in the speed increasing direction or from the neutral position in the decelerating direction by observing the shift direction of the bar 12, so that the time required to complete the speed change is significantly reduced as compared with the conventional device. Not only contributes to improving work efficiency, but also suppresses sudden changes in vehicle speed,
The operation feeling is also improved with less lock .

BRIEF DESCRIPTION OF THE 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 a state of control. FIG. 6 is a table illustrating the number of gear positions. [Description of Signs] 1 Tractor 2 Front wheel 3 Rear wheel 4 Engine 9 Main transmission 10 Sub transmission 11 Forward / reverse switching device 12 Shift lever 18 Control unit 40 Position sensor 41 Position sensor

Claims (1)

(57) [Claim 1] A main transmission 9 capable of a plurality of speeds and a sub-variable.
A speed change device 10 and a forward / reverse switching device 11;
The switch 10 is operated by operating the operation lever 12 in the front-rear direction to switch.
The main transmission 9 is a shift switch 1 provided on an operation lever 12.
Powered vehicle configured to switch by operating 4
In addition, a sub-position for detecting a shift position is provided at the base of the operation lever 12.
A shift position sensor 41 is provided, and is operated by the operation lever 12.
As soon as the sub-shift operation is started, the main transmission 9 is temporarily stopped.
At the neutral position, and the auxiliary transmission 10
Side, the main transmission 9 is switched to the reduction side, and
When the transmission 10 is switched to the reduction side, the main transmission 9 is increased.
A control unit 18 for switching to a high-speed side.
Transmission for power vehicles .