JPH0650686Y2 - Structure for prioritizing speed change operation of hydraulic automatic steering vehicle - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a hydraulic automatic steering vehicle equipped with a hydraulic transmission and an automatic steering device, and when the both devices are operated in parallel, the transmission is always changed. The present invention relates to a shift operation priority structure in which the operation of the device has priority.

[Conventional technology]

An automatic speed change gear including a speed change device for operating a speed change member of a speed change device by a hydraulic cylinder and an automatic steering device for effecting an automatic steering operation by intermittently operating a power interrupting member of a steering device with a hydraulic cylinder. Oncoming vehicles are used for agriculture and earthworks.
However, since the shifting cylinder is a double-acting type and the steering cylinder is a single-acting type, it was not possible to connect these cylinders in series (double-acting type) as long as there is simultaneous operation. Type cylinders must circulate pressure oil, and single-acting type cylinders do not circulate pressure oil).

[Problems to be solved by the device]

Therefore, it was necessary to separately provide a hydraulic system such as a hydraulic pump. Therefore, the price is high,
The installation space also required a large area.

As a solution to this problem, the inventors of the present invention have automatically operated the gearshift switch, which operates during gearshift operation, and the exciting coil of the solenoid valve for steering, until the gearshift switch is turned off. We have previously proposed a case of keeping the controller of the control device in a non-operating state as Japanese Utility Model Application No. 63-133905.

However, if the shift valve is a manual valve, no electrical signal can be obtained and it cannot be operated electrically.

Therefore, the present invention detects the movement of the shift lever, converts the amount of movement into the time until the shift cylinder finishes operating, and stops the function of the automatic steering device during this time. Therefore, the above-mentioned problems are to be solved.

[Means for Solving the Problems]

That is, the present invention switches the flow path to a steering cylinder consisting of two single-acting cylinders constituting an automatic steering device in series with a manual valve controlling a transmission cylinder consisting of a double-acting cylinder constituting a transmission. In a hydraulic automatic steering vehicle to which a solenoid valve is connected, the amount of movement of the speed change lever that operates the manual valve is converted into a digital signal amount by a potentiometer and an A / D converter, and this digital signal amount is changed by the microcomputer. Converting to the amount of time until the cylinder finishes operating, and within this time, shift operation of a hydraulic automatic steering vehicle by operating a relay that cuts off the ground wire of the control circuit of the controller that controls the automatic steering device It provides a priority structure.

[Action]

By taking the above means, the amount of movement of the gear shift lever is converted into the amount of time until the gear shift operation is finally ended. Therefore, if the automatic steering device is kept inactive during this period,
Even during the automatic steering, the gear shifting operation has priority.

〔Example〕

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
The drawing is an electrohydraulic circuit diagram of a shift operation priority structure according to the present invention.

That is, the pressure oil discharged from the pump 1 is supplied to the double-acting type shift cylinder 3 constituting the transmission device via the 4-port 3-position manual valve 2. When the manual valve 2 is in the neutral position, the pressure oil circulates to the tank 4. In this case, the oil pipe on the return side is divided into two (to turn to the left and right respectively) that make up the automatic steering device. 4) Switching the flow path to single-acting steering cylinders 5 and 6
Connect to solenoid valve 7 of port 3 position type.

By the way, regarding the transmission and the automatic steering device in this case, first of all, the transmission is composed of a transmission lever 8, a transmission cylinder 3 and a manual valve 2 for controlling the transmission lever 8 based on the so-called position control principle. There is.
That is, a differential planetary mechanism type continuously variable transmission (trade name: ring cone) is used as the speed change element, and the shift operation of the speed change ring 10 on the planet cone 9 is performed by the speed change cylinder 3.
I am trying to do it. Specifically, the transmission lever 8 is connected to the spool of the manual valve 2 via the rod 11.
2a is connected to one end of a stroke lever 12 which is connected to the middle part of 2a, and the other end of this lever 12 is also connected to the rod 13
It is fixed to the rod 3a of the speed change cylinder 3 via the and is connected to the feedback lever 15 which is rotated by the movement of the fork 14 which holds the speed change ring 10. Therefore, when the shift lever 8 is rotated by a certain angle, the pivot lever 12 is moved to the fixed point and the stroke lever 12 is moved to switch the manual valve 2. Then, the shift cylinder operates to move the shift ring 10 (shifting is performed), and at the same time, the fork 14 moves, so that the feedback lever 15 also connects the rod 11 which is connected to the shift lever 8 this time.
The pivot point is fixed and the arm rotates to return to the original equilibrium state (the manual valve 2 is neutral). From this,
The larger the rotation angle of the speed change lever 8, the longer it takes for the manual valve 2 to return to the equilibrium state, so the amount of movement of the speed change cylinder 3 also increases and the amount of speed change also increases.

Next, regarding the automatic steering device, this is a system in which hydraulic clutches are respectively provided in drive systems leading to the left and right axles, and the hydraulic clutches are operated as the steering cylinders 5 and 6 described above.

On the other hand, if the two valves 2, 7 are connected as described above, both cylinders 3, 5 (6) cannot be operated at the same time (the shift cylinder 3 does not move for a predetermined stroke, and the shift operation cannot be performed. ).

However, by controlling this with the following configuration, even when both cylinders 3, 5 (6) try to operate simultaneously, the operation of the speed change cylinder 3 always takes precedence, and then the steering cylinder 5 , 6 will be activated.

That is, the potentiometer 17 is connected to the predetermined power source 16,
The movable terminal 17a is mounted on the shift lever 8 for operating the manual valve 2, and the A / D converter 18 and the microcomputer 19 are connected to the circuit below the movable terminal 17a. on the other hand,
The exciting coil 20a of the relay 20 is connected to the circuit of the power source 16 and the output device 19 of the microcomputer 19 is connected in series with the exciting coil 20a.
Also connect a. Further, the closed contact 20b of the relay 20 is provided on the ground wire 22 of the control circuit of the controller 21 that controls the automatic steering device. In addition, this ground wire
22 has a switch 23 that cancels the operation of the automatic steering device.
And changeover switch 2 for selecting the left and right steering cylinders 5 and 6
4 and are provided.

As described above, assuming that a shift operation is performed by moving the shift lever 8 while the solenoid valve 7 is being switched to operate the automatic steering device, this operation causes the movable terminal 17a of the potentiometer 17 to move. From (this terminal 17a is linked to the speed change lever 8 by the rod 8a etc.), the changed analog signal amount is the A / D converter 1
It is converted into a digital signal amount by 8, and further converted into a predetermined time amount by the microcomputer 19, and is output to the output device 19a. Then, during this time, the closed contact 20a of the relay 20 is opened and the ground wire 22 of the controller 21 is opened.
To shut off the operation. Then, when this predetermined time elapses, the closed contact 20b of the relay 20 is closed again and the controller 21 is reactivated. At this time, the predetermined time output from the microcomputer 19 is the operation end time of the shift cylinder 3 corresponding to the movement amount of the shift lever 8.

[Effect of device]

As described above, since the present invention has been described above, the following effects can be expected.

i) When the steering cylinders 5 and 6 are operated to perform a gear shift operation while performing automatic steering and fit steering,
The operation of the automatic steering device is temporarily interrupted, and priority is given to gear shifting operations.
When the predetermined gear shifting operation is completed, the automatic steering device is activated again. Therefore, the disguise device and the automatic steering device can be driven by one hydraulic system. In addition,
In this way, priority is given to gear shifting over steering.
Zero shifting is also given priority in an emergency, so it is extremely significant in terms of safety.

ii) Although such a low price for gear shifting operation can be used, the manual valve 2 that cannot be electrically controlled can be used, so that a low cost can be provided without degrading the function.

[Brief description of drawings]

 The drawing is an electrohydraulic circuit diagram showing an embodiment of the present invention. (Reference number) 2 ... Manual valve for shifting 3 ... Shifting cylinder 5 ... Steering cylinder 6 ... 〃 7 ... Solenoid valve for steering 8 ... Shifting lever 17 ... Potentiometer 18 ... A / D Converter 19 …… Microcomputer 20 …… Relay 21 …… Controller 22 …… Ground wire

Claims (1)

[Scope of utility model registration request] 1. A manual valve (2) for controlling a speed change cylinder (3) comprising a double acting cylinder constituting a speed change device.
In a hydraulic automatic steering vehicle in which a solenoid valve (7) for switching the flow paths to the steering cylinders (5) and (6), which are composed of two single-acting cylinders that constitute an automatic steering device, are connected in series, The amount of movement of the speed change lever (8) for operating the manual valve (2) is converted into a digital signal amount by a potentiometer (17) and an A / D converter (18), and this digital signal amount is converted by a microcomputer (19). A relay (20) for converting the amount of time until the shift cylinder (3) finishes operating, and disconnecting the ground wire (22) of the control circuit of the controller (21) for controlling the automatic steering device within this time. A structure for prioritizing speed change operation of a hydraulic automatic steering vehicle that operates by.