JP2000064870A - Engine rotation control device for farm working machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate escape from a slip state in the mud so as to improve the operability of a vehicle by providing a control means for changing engine rotational speed to the low speed side upon detecting the actuation of a differential locking device. SOLUTION: The rotating power of an engine is transmitted through a differential gear 3F, and left and right front wheels 1, 1 are differentially rotated. When a differential locking pedal 26 is depressed, the left and right front wheels 1, 1 lose differential action and are forcibly rotated synchronously. The rotating base part of the differential locking pedal 26 is provided with a differential locking operation detecting switch 5, and when the differential lock detecting switch 5 is on, a controller reduces engine rotational speed to reduce the rotating speed of wheels slipping in the mud or the like. At the same time, a timer is actuated, and a differential lock state is released after a fixed time. Escape from the mud is therefore facilitated by a low speed travel state. After the escape from the mud, speed is automatically reset to improve operability.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a configuration of an engine rotation control device of an agricultural work machine such as a tractor, a rice transplanter, or a lawn mower. 2. Description of the Related Art
2. Description of the Related Art A known agricultural work machine such as an agricultural tractor is provided with a differential lock device on a front wheel or a rear wheel in order to ensure that a vehicle travels straight. However, conventionally, when the wheel of the agricultural working machine slips, specifically, when one of the left and right wheels slips to avoid this state, first, it is necessary to turn on the differential lock device and to escape from the slip state at low speed traveling. It was necessary. Further, if this is neglected, there is a problem that the idling wheel forms a large groove in the field, and the subsequent work, for example, the planting condition of the crop becomes poor. [0003] The present invention is to solve the above-mentioned problems, and has taken the following technical means. That is, the vehicle includes the differential device 3 for the front wheel 1 or the rear wheel 2, the differential lock device 4 for stopping the differential operation of the differential device 3, and the means 5 for detecting the operation of the differential lock device 4 or the input operation. The engine 6 of the vehicle is provided with an engine rotation adjusting means 7 for adjusting the number of rotations, and a control means 8 for changing the number of rotations of the engine to a low speed side when the operation or the on-operation of the differential lock device 4 is detected. And an engine rotation control device for an agricultural work machine. The engine rotation control device for an agricultural work machine having the above-described configuration operates to lock the differential rotation of the front wheels or the rear wheels when the differential lock device 4 is operated. The rotation speed is changed to the low speed side.
As a result, the vehicle enters a low-speed running state, easily escapes the slip state in mud, and the operability of the vehicle can be improved. An embodiment of the present invention will be described below based on an agricultural tractor. The tractor 10 is shown in FIG.
As shown in FIG. 3 to FIG. 3, an engine 12 is provided in a hood 11 at the front of the vehicle body, and a front axle housing 13 is rotatably supported behind an oil pan of the engine 12. The front wheel 1 is pivotally supported via a case 14. The rotational power of the engine 12 is transmitted via a metal axle case 16 via an output shaft 15 and a transmission mechanism in front and rear transmission cases 17F and 17R, and after being pivotally supported on the side of the rear transmission case 17R. The transmission is to the wheel 2. The rotational power is transmitted again to the front of the vehicle body via the front wheel drive shaft 18 and is input to the front axle housing 13 to drive the front wheels 1. The engine 12 is a diesel engine, and is configured such that the throttle position of the governor device is changed by an electric motor 7 which is an engine speed adjusting means provided on the side of the engine. Thus, when the electric motor 12 is energized, the rotation speed of the engine 12 can be changed to a lower speed. Explaining the vicinity of the cockpit 19 of the tractor 10, a meter panel 21 having a monitor lamp 20 is provided at the rear of the hood 11 and the front wheel 1
A steering handle 22 for steering
An accelerator lever 23 is provided below this. A left and right brake pedal for independently braking the left and right rear wheels 2 and 2 and a clutch pedal 2 are provided below the cockpit 19.
5, and a differential lock pedal 26 as a means for turning on and off a differential device 3 to be described later. A differential lock operation detection switch 5 for detecting a depression operation of the pedal 26 is provided at a rotation base of the differential lock pedal 26. Further, a damper 28 is connected to the base of the rotating arm 27 of the clutch pedal 25, and the connection of a main clutch 29 to be described later is loosened even when the clutch pedal 25 is suddenly depressed. It is configured to prevent shock. Incidentally, the reference numeral 24 in the figure denotes the rotating arm 2.
A spring 32 for urging the clutch 27 toward the clutch input side, and 32 indicates an input shaft of the arm 27 to the inside of the case. On the left and right sides of the cockpit 19, there are provided a working machine elevating lever 35 and various setting devices.
0, the electric motor 7, and the differential lock operation detection switch 5 are connected to a controller 8 as a control means. Incidentally, reference numeral 36 in FIG.
Reference numeral 7 denotes a hydraulic cylinder for lifting and lowering the working machine operated by the lever 35 for lifting and lowering the working machine, and 38 denotes a rotary working machine connected to the hydraulic cylinder. Next, the power transmission configuration of the tractor 10 will be described with reference to FIG. In the engine 12, the rear end of the crank pulley 40 and the front end of the input shaft 15 are connected via a rubber coupling 41 as an elastic member. Thereby, the hydraulic pump 42 described later can be used for the variation of the rotation of the engine 12, especially for the fluctuation at the time of low rotation.
Pulsation is suppressed, and stable oil lubrication is performed. The rotational power output from the engine 12 is input to the axle case 16 via the input gear 43 at the rear end of the output shaft 15, and is further turned on and off by the wet-type multi-plate main clutch 29. 17F. Further, the rotational power is generated by a key-slide type main gear including a first speed gear 44, a second speed 45, a third speed 46, a forward gear group which always meshes with these gears, a reverse gear group having a counter gear 47, and the like. Transmission 4
8 and the height of the slide gear 31
The transmission is decelerated via the auxiliary transmission 51 for performing the speed change, and is input to the rear wheel differential 3R. The clutch shaft 30 supporting the main clutch 29 is provided with a tip end protruding from the axle case 16 and is used as a drive shaft of a hydraulic pump 42 provided in contact with the front surface of the axle case 16. It is configured to input. The rotational power reduced by the auxiliary transmission 51 is transmitted through the front wheel drive transmission gear 52 to the front wheel drive shaft 1.
8 is transmitted. And the front wheel drive shaft 1
Numeral 8 is configured to input to the front wheel differential device 3F in the front axle case 14. The axle case 16 and the front transmission case 17F are separated from each other by an intermediate wall, and the front and rear spaces are defined by an upper hole 53 opened above the gear of the main transmission 48 on the same wall. Also, a small-diameter communication is made through a lower hole 54 through which the front wheel drive shaft 18 is inserted, and tank ports of various hydraulic devices are provided in the upper portion of the main clutch 29 so as to be opened. Thus, even when traveling on an inclined ground such as an orchard, for example, oil is preferentially accumulated on the case side storing the main clutch 29 to lubricate the oil. The differential lock device 4 is, as shown in FIG.
It is provided in the front ax case 13 and is provided on a left drive shaft 55 protruding from the front wheel differential device 3F. More specifically, a lock claw 56 is provided on a left portion of the differential device 3F, and a differential lock shaft 57 which is spline-fitted in the left-right direction is provided on the left drive shaft 55. The shifter 58 for operating the differential lock shaft 57 and the differential lock pedal 26 are connected via a link mechanism, a wire, and the like. The differential lock shaft 57 is moved outside the vehicle body by a spring 59.
That is, it is configured to be biased to the differential lock release side. In the illustrated example, the engine rotational power is normally supplied from the input gear 43 of the front axle case 13 to the differential gear 3.
F—transmitted to the left drive shaft 55 and the final case 1
The power is transmitted to the left front wheel 1 through the speed reduction mechanism 60 inside 4.
As a result, the left and right front wheels 1 and 1 rotate differentially. Further, when the differential lock pedal 26 is depressed, the shifter 58
, The rotational power is supplied to the input gear 43 of the front axle case 14, the lock pawl 56, and the differential lock shaft 57.
Transmitted to the left drive shaft 55, the left and right front wheels 1, 1 lose their differential action and forcibly rotate. The power transmission configuration on the right side of the front axle case 13 is omitted. The controller 8 has a cockpit 19
It is provided below and has a CPU as an arithmetic means, an EEPROM for storing a control program and the like, a RAM for temporarily storing various information, a timer, and the like.
A differential lock operation detection switch 5 is provided on this input side.
And the like, and an actuator such as the monitor lamp 20 and the electric motor 7 is connected to the output side. The engine rotation control device of the tractor 10 configured as described above operates according to the flowchart shown in FIG. This flowchart shows the outline of the control program stored in the storage device of the controller 8. First, the engine 12 of the tractor 10
Is driven to turn on the electric system, the controller 8 reads the connection state and detection state of various sensors. Then, the ON / OFF state of the differential lock detection switch 5 is determined,
When this is ON, the electric motor 7 is energized. As a result, the engine speed decreases, and the vehicle speed of the tractor 10, that is, the rotation of the wheels that run idle in mud or the like, is reduced. At the same time, the time is measured by a timer, and the measured time is exceeded, or the differential lock operation detection switch 5 is turned off.
When it becomes FF, the energization is stopped and the differential lock state is released. As a result, the tractor 10 operates the differential lock pedal 26, the engine speed is reduced, and the tractor 10 enters a low-speed running state, so that escape in mud becomes easy. In addition, since the low-speed state is released after a certain period of time, the speed is automatically restored even after the escape in mud, and the operability of the vehicle can be improved without requiring the operator's trouble. In the above description, the start of the control operation is detected by providing the differential lock operation detection switch 5 at the rotation base of the differential lock pedal 26 which is an operation unit. Instead, the shifter on the operation side is detected. It may be configured to detect the displacement of the differential lock shaft 58 or the differential lock shaft 57.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional view of a front axle housing showing an operation of a differential lock device. FIG. 2 is an overall side view of the tractor. FIG. 3 is a side view of a tractor showing a clutch pedal unit. FIG. 4 is a diagram showing power transmission. FIG. 5 is a block diagram showing a connection state of a controller. FIG. 6 is a flowchart showing an outline of control [Description of symbols] 1 front wheel 2 rear wheel 3 differential device 4 differential lock device 5 differential lock operation detection switch 6 engine 7 electric motor 8 controller

   ────────────────────────────────────────────────── ─── Continuation of front page    F term (reference) 3D036 GA05 GA38 GB10 GD01 GD05                       GG15 GH16 GH17 GH22 GJ12                       GJ13                 3D041 AA00 AA47 AB04 AC02 AC04                       AC11 AC13 AC24 AD00 AE04                 3G093 AA09 BA00 BA01 CB14 DB00                       DB23 EA07 EC02                 3G301 HA02 JA38 LA01 LC03 PG00Z

Claims (1)

Claims: 1. A differential device 3 for a front wheel 1 or a rear wheel 2,
A differential lock device 4 for locking the differential operation of the differential device 3 and a device 5 for detecting the operation or operation of the differential lock device 4 are provided. Control means 8 for changing the engine speed to a low speed side when the operation or the on-operation of the differential lock device 4 is detected.
An engine rotation control device for an agricultural work machine, comprising: