JPS61104145A - Governor device of working vehicle - Google Patents

Abstract

PURPOSE:To enable running at a constant speed of a working vehicle and driving at a constant speed of a working device and to improve manerverability, by a method wherein a fuel injection amount regulating mechanism for an engine is controlled by a motor-operated actuator electrically linked to an accel regulating tool through a control circuit. CONSTITUTION:A fuel injection amount regulating mechanism 12 of a fuel injection pump 11 mounted to an engine is controlled by a control circuit 18 and a motor-operated actuator 13. By the use of a manually-operated accel regulating tool 19, an accel set value is outputted by a rotary potentiometer 20. A control circuit 18 shifts governor characteristics into a mode for running on a road and a mode for working running to perform control of fuel. This enables to perform smooth running on a road and working running of a working vehicle.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention mainly relates to a governor device used in a diesel engine-equipped agricultural working vehicle such as an agricultural tractor or combine harvester.

[Conventional technology]

If we categorize the governor device that controls the fuel injection pump of the Diesel I Rengin by characteristic pattern, we will find two types: one is a bead governor that can control the speed in all rotation ranges from idling to maximum rotation, and the other is a bead governor that allows for smooth idling. , and do not exceed the maximum rotation speed t
In order to achieve this, the speed regulating effect is exerted only in the low speed rotation range and high speed rotation range,
There is a minimum/maximum speed governor that does not perform speed regulating action in the middle rotation range.

In the above-mentioned agricultural work vehicles that require stable constant-speed running and constant-speed drive of working equipment regardless of load changes (the former Au Respeed governor is adopted, and it also responds quickly to accelerator adjustment). The latter minimum/maximum speed governor is suitable for automobiles that require smooth acceleration and deceleration.

[Problem that the invention seeks to solve]

By the way, in recent years, there has been a strong trend towards faster speeds for the above-mentioned agricultural vehicles due to improvements in work efficiency and mobility.
It is becoming possible to fully handle not only work in the field but also high-speed transportation work on the road.

However, as mentioned above, the Baka device installed in the engine of the agricultural work vehicle has been selected to use Ole Speed, which is suitable for its main work in the field. The feeling of deceleration (drivability) was not good.

Also, in recent years, in the relatively low rotation range, the minimum and maximum speeds are close to the characteristics of Baka, and in the relatively high speed range - l speed is close to the characteristics of Baka, and the characteristics are intermediate between both types. It seems that it has also been developed,
Agricultural vehicles often perform field work with light loads at low rotational speeds, so the above-mentioned devices with intermediate characteristics can only work at stable rotational speeds over a wide range of rotational speeds. K to be introduced immediately had fry.

This invention attempts to solve the above-mentioned problems by employing a so-called electronic control governor that controls the operation of the injection amount adjustment mechanism using two electric actuators.

Means for Solving Problem C] Therefore, in the present invention, the fuel injection amount adjustment mechanism of the installed diesel engine is operated by an electric actuator that is electrically linked to the manually operated accelerator adjustment tool via a control circuit. In addition, there is a road driving mode that controls the fuel with the force and speed characteristics set to the TR I Rec curve, which has a small rate of torque fluctuation with respect to engine speed fluctuations, and a TREF curve, which has a large torque fluctuation rate with respect to engine speed fluctuations. However, due to the characteristics of the fuel, the control circuit can be set to control the work driving mode, and both modes can be switched and selected.

[Effect]

According to the above-mentioned configuration, the governor characteristic for the work driving mode and the slow speed characteristic for the road driving mode can be freely set in advance by the control circuit, and the desired mode can be easily used by electrical commands.

〔Effect of the invention〕

Therefore, when the work equipment is being used for work, it is possible to perform the speed regulating function in all rotational ranges to perform the desired constant speed travel or constant speed drive of the work equipment, and it is also possible to drive the work equipment on the road to and from the work site. When driving on the road or on a transport road, the vehicle can smoothly accelerate and decelerate in response to accelerator adjustment, and its mobility can now be increased without compromising its inherent vA performance as a work vehicle.

〔Example〕

The case where the present invention is applied to an agricultural tractor will be described below.

Diesel engine (2) mounted on the tractor body (1)
) is transmitted to the transmission case (4) via the main clutch housing +31'k, where the gear is changed as appropriate and transmitted to the rear wheel (5) or the front and rear wheels.
At the same time, working power is branched and transmitted to the rear PTO shaft (7) via a live Pτ0 transmission system independent of the travel transmission system, and a hydraulic lift arm (8) and a three-point link mechanism ( 9) is an example of a working device that is connected so as to be able to rise and fall freely [101 is the above-mentioned P
It is designed to be driven by the output from the TO axis (7).

The control mechanism (2), which is a fuel injection amount adjustment mechanism for the fuel injection pump (6) equipped with the engine (2) K, is electronically controlled by an electronic controller.

Tsumasu 1. The control rack (2) is connected to a solenoid (to) which is displaced with a stroke proportional to the excitation current, and the position of the control gr-r rack (6) is determined by the next stroke sensor Q4 using a differential transformer. The engine rotation speed is detected as a pulse signal by the coil I sensor αη which is continuously detected and is opposed to the gear (7) fixedly installed at the time of the pump driving camshaft α, and the engine rotation speed is detected as a pulse signal by the coil I sensor αη, The controller 2 is configured to control the position of the controller 2 based on the information and an activation setting value that is separately set manually.

This electronic governor is controlled via a control circuit using a microcomputer, and a block diagram thereof is shown in FIG.

In this electronic governor, the accelerator I is operated manually.
As the J4N tool, a single door access I lever is used that can frictionally hold the lever at any operating position in the entire range from idling to maximum speed, and also outputs the set value when actuating. A rotating potentiometer is equipped on the lever pivot.

Furthermore, in this electronic governor, two types of governor characteristics are set in advance by the MJa circuit. One of them, as shown in Figure 3, is that the torque f
, # small rate? It is set in the rec carp,
It is mainly used for road driving. On the other hand, as shown in Fig. 4, the Torek curve KIR is determined, which has a large Torek variable ratio with respect to engine speed fluctuations.
It is mainly used for work traveling, and these double-edged spanner characteristics are selectively utilized based on commands from the control mode selection switch (2).

In the mode using the on-road governor characteristics,
Map control is performed. In the Trek Carp shown in Figure 3, the relationship between the engine speed and the control reflex 2 position (Trek I) is stored in advance as map data for each accelerator setting value. The map control system calculates the target rack position (PL) for the detected engine speed based on the map data corresponding to
PIDi#IJ controls the lenoid Q3 so that it goes toward the direction l).

Further, in the mode using the governor characteristics for work traveling, PID rotation speed control is performed. In other words,
In this case, the given aku 7? The set value means the target rotation speed, and the PrD rotation speed control system changes the target rack w < p so that there is no difference between the target rotation speed and the detected rotation speed.
ρ is calculated and input into the rack position PID control system.

Note that to prevent engine stop and overspeed, minimum rack position control and maximum rack position control are also performed. In other words, the target rack calculated by the map control system ■ or the PID rotation speed control system! (Pa or (Pa) and the lowest rack position set based on the detected engine speed (
Pa is compared in the first discrimination system (2), and the larger one is selected as the target rack position (P,) to prevent the engine from stopping. In addition, as described above, the target rack position (P4) selected by the control system and the maximum racking M (
Pa) are compared in a second discrimination system, and the smaller one of them is selected as the final target rack position (Pa) to prevent engine overrun.

In addition to installing the mode changeover switch (211) as a dedicated switch, the main key switch can also be provided with two types of mode selection positions.

It is also possible to automatically switch the mode, for example, by switching the drive cylinder (
Equipped with a pressure switch that detects the internal pressure of It is also possible to switch to the road driving mode or, in the coupled state, to the working driving mode on a self-help basis.

In addition, since the unevenness of the ground in a working area (field) is generally larger than that of a road surface, the unevenness of the road surface can be detected by a contact method or a non-contact method (using an ultrasonic sensor, etc.), and based on this, the above mode can be set to a self-help mode. It is also possible to switch to

In addition, the footbeda can be restored as a dedicated accessory A'% joint in road driving mode! It is also possible to provide a hand accelerator lever as a dedicated accelerator adjustment tool in the work driving mode, and use the accelerator adjustment tool depending on the mode selection.

The model of the fuel injection pump 0υ may be other than the above,
Further, instead of the solenoid for the fuel injection amount 'IA clause, a DC electric motor (equipped with a reduction gear) may be used, and these are collectively referred to as electric actuators.

[Brief explanation of the drawing]

The drawings show an embodiment of the pannier device for a work vehicle according to the present invention, FIG. 1 is a control block diagram, FIG. 2 is a configuration diagram of the governor device, FIG. 3 is a governor characteristic diagram in road driving mode, and FIG. FIG. 4 is a characteristic diagram of the governor in the work driving mode, and FIG. 5 is an overall side view of the agricultural tractor. (2)...Engine, (2)...Fuel injection amount adjustment mechanism, (2)...Electric actuator, (to)...Control circuit, al...Accelerator adjustment tool, Co., Ltd....Mode changeover switch.

Claims (2)

[Claims] (1) The fuel injection amount adjustment mechanism (12) of the installed diesel engine (2) is controlled by the accelerator adjustment device (1) that is manually operated.
9) is operated by an electric actuator (13) that is electrically linked via a control circuit (18), and the fuel is controlled using a governor characteristic set to a torque curve with a small torque fluctuation rate with respect to engine speed fluctuations. The control circuit (18) is configured to set a road driving mode and a work driving mode in which fuel is controlled using governor characteristics set to a torque curve with a large torque fluctuation rate with respect to engine speed fluctuations, and both modes can be switched and selected. The governor device of the working vehicle. (2) The governor device according to claim 1, wherein the control mode is arbitrarily switched by manual operation of a switch (21).