JPH03187311A - Control device of speed of working vehicle - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a vehicle speed control device for a working vehicle.
More specifically, a transmission installed in the traveling system is interlocked and connected to the engine, and a vehicle speed control means is provided to control deceleration of the transmission, and furthermore, a turning system is provided to determine whether or not the work vehicle is in a turning state. a traveling detection means and an engine rotation detection means for detecting the engine rotation speed of the working vehicle, when the working vehicle is in the turning traveling state and the engine rotation speed becomes lower than a deceleration processing setting value. ,
The present invention relates to a vehicle speed control device for a work vehicle in which the vehicle speed control means operates.

[Prior Art] Conventionally, in this type of vehicle speed control device, two main types of vehicle speed control methods during cornering have been known. That is, the first control method is to perform deceleration control at the time when the work vehicle enters the turning state to perform turning in a one-step decelerated state, and the second control method is to control the turning state. Regardless of whether the vehicle is in any running state or not, when the engine speed decreases to the deceleration processing setting value due to an increase in the load associated with the vehicle, the deceleration control described above is performed and the gear is changed.

These methods have the disadvantage that engine power cannot be used effectively depending on the road surface and driving conditions. Therefore, a system has been proposed in which the above-mentioned deceleration control process is performed only when the work vehicle is in a turning state and the engine rotational speed is lower than the deceleration process setting value due to the load associated with the turning movement.

[Problems to be Solved by the Invention] When adopting a control method having the structure described above, conventional deceleration processing setting values are such that the engine This was determined in advance as the engine rotational speed at which deceleration processing is required when running load is applied while the engine is being used at maximum output.

Therefore, the necessity of deceleration control processing has not been determined based on the actual engine rotational speed, which accurately represents the actual usage state of the engine. In such a device, for example, using a combine harvester as an example, after finishing the reaping and threshing work, the operator simply drives straight ahead, changes the accelerator setting to low rotation, and then tries to turn. As a result, the engine speed may be set below the deceleration processing setting value mentioned above, which satisfies the condition that deceleration processing is performed only when turning, resulting in failure even though no excessive turning load has occurred. Necessary deceleration control was to be carried out.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to eliminate the above-mentioned conventional drawbacks, and when decelerating a working vehicle in a turning state, it takes into consideration the state of the engine when traveling straight before turning, and thereby controls deceleration control. To provide a vehicle speed control device for a work vehicle that can properly judge whether it is necessary or not and can always use an engine in a good condition without waste.

[Means for Solving the Problem] In order to achieve this object, the first invention of the present application is a vehicle speed control device for a working vehicle, wherein the vehicle speed control means determines the deceleration processing setting value based on the engine rotation speed before turning. In addition, the second invention of the present application has the above configuration,
When the engine speed during turning is lower than the reference target value plus the margin value, the vehicle speed control means sets the deceleration processing setting value to a value obtained by subtracting the margin value from the engine speed before the turn. If the engine speed during cornering is higher than the sum of the reference target value and the margin value, the reference target value is selected as the deceleration processing setting value. That's true.

[Function] This vehicle speed control device for a work vehicle has a vehicle speed control means, and is configured such that the vehicle speed control means is activated when the work vehicle is in a turning state and the engine speed becomes lower than a deceleration processing setting value. There is.

According to the first characteristic configuration of the present application, this deceleration processing setting value is determined based on the engine rotation speed before turning.

In other words, for example, if the engine speed before turning is a relatively high value and the engine is being used in good condition, the deceleration processing setting value is determined as a standard value, and the engine speed before turning is low. When the engine is being used in a state that is not ideal, a deceleration processing setting value suitable for this state is determined from the engine speed before turning, and the above-mentioned deceleration control processing is performed based on this standard. That is to say.

In addition, according to the second characteristic configuration, the engine speed before turning is compared with a value obtained by adding a margin value to a reference target value as a deceleration processing value when the engine is used in an ideal condition, and A distinction is made between a state in which the setting is appropriate and the engine is used at maximum output with sufficient margin, and a state in which the accelerator setting is lower than the ideal state and the engine is used with no margin in output. In the former case, the reference target value is selected as the deceleration processing setting value, and execution of the deceleration control processing is determined based on this, and in the latter case, the value obtained by subtracting the above margin value from the actual engine rotation speed before turning is selected. This is selected as the deceleration processing setting value, and it is determined whether or not to execute the deceleration control processing based on this value.

[Effect of the invention] Therefore, in the configuration of the first invention of the present application, the actual usage state of the engine is determined from the engine rotation speed before turning,
In addition, the optimal deceleration control processing is performed according to the turning load during turning, so it is possible to prevent problems such as engine stalling, avoid unnecessary deceleration processing, and efficiently increase engine output without waste. can be used.

In addition, the deceleration processing setting value is not a fixed value as the deceleration control value in the maximum output state as in the past, but the engine rotation speed before turning is used to determine the deceleration processing setting value. The deceleration process during turning is not affected by changes in the accelerator setting by the operator during harvesting, and situations that cause the engine to stall are avoided even when the running load increases significantly due to a sharp turn. can do.

In addition, in the configuration of the second invention, the engine speed before turning and the value obtained by adding the margin value to the reference target value are compared,
Since the deceleration processing set value is determined as a value suitable for each state, it is possible to perform control that takes margin values into consideration, rather than performing deceleration control that is judged only based on the standard target value as in the past. We were able to obtain a control device suitable for this purpose.

[Example] Hereinafter, a case in which the present invention is applied to a vehicle speed control device for a combine harvester as an example of a work vehicle will be described based on the drawings.

As shown in Fig. 3, the combine harvester includes a machine body (V), a crawler traveling device (1), and a threshing device (1) as a working device.
2), and a reaping section (3) and a control section (4) are provided at the front of the machine body (V).

The reaping section (3) includes a triggering device (5) that raises the grain culm in the field, a cutting blade (6) that cuts the base of the raised grain culm, and a rear part of the machine while changing the posture of the harvested grain culm to a sideways posture. Each is provided with a conveying device (7) for conveying the threshing toward the side threshing feed chain (8). In addition, the above-mentioned reaping part (
3) is provided so as to be movable up and down with respect to the body (V).

As shown in FIG. 1, the engine (E) and the crawler traveling device (1) are connected to a hydraulic continuously variable transmission (9) as a transmission and a pair of left and right steering clutch brakes (16).
and the engine (E)
and the handling cylinder (lO) of the threshing device (2) are interlocked and connected via a belt tension type threshing clutch (11).

A rotation speed sensor (S2) is provided as rotation detection means for detecting the rotation speed of the engine (E).

The transmission (9) is operatively connected to a manually operated transmission lever (13) via a link mechanism (12). A speed change motor (14) serving as a speed change actuator is operatively connected to the link mechanism (12) via a friction type transmission mechanism (15). In other words, while the speed change lever (13) can be used to manually change the speed, the speed change motor (14) can also be used to automatically change the speed. The pair of steering clutch brakes (16) can each be switched into four stages by a control valve (17). That is, there are four stages: "forward rotation", "clutch disengagement", "clutch disengagement and braking", and "reverse rotation".

The control valve (17) is connected to an operating lever (18) and can be manually operated. still,
This operating lever (18) is also connected to a control valve (19) for raising and lowering the reaping section (3).

Although not described in detail, the operating lever (18) is constructed in a cross-swing type and is biased to return to the neutral position (N). It can be swung left and right in three steps. For example, when the vehicle is swung one step to the right, the power to the right traveling device (1) is cut off. When you swing it up to the second stage, the right traveling device (
A braking force is further applied to 1). In the third stage, reverse power is applied to the right traveling device (1). When rocking to the left, the left traveling device (
1) will act in the same way. Also, when the operating lever (18) is swung backward, the reaping section (3
) is raised and swung forward, the reaping section (
3) of the reaping section (3).
20).

Further, a turning sensor (SL) serving as turning detection means (S1) is provided near the base of the operating lever (18). The turning sensor (SL) is used to detect whether the work vehicle is in a turning state, and when the operating lever (18) is kept at the machine turning position for a certain period of time, it sends a turning signal. It is detected as follows. Detection information from the aforementioned turning detection means (S1) and engine rotation detection means (S2) is collected in a vehicle speed control means (100) provided in a vehicle speed control device.

A microcomputer-based vehicle speed control means (100) that operates the speed change motor (14) to reduce the vehicle speed will be described below. This vehicle speed control means (
100) is shown in FIG. 2.

This flow is a flow for determining whether or not to perform deceleration control processing as the processing operation in step 5, and also has a function of determining with respect to which reference value this deceleration control should be performed.

Explain the steps step by step.

In this flow, when the work vehicle is not turning,
From judgment step 1, the process moves to step la. In this step 1a, the engine speed (R) from the speed sensor (S2) is averaged, and this is stored as the straight-ahead engine speed (Rx). This process continues as long as the work vehicle continues to travel straight. Therefore, the engine speed at the end of the straight-ahead travel state is stored as the straight-ahead travel engine rotation speed (Rx). As shown in the figure, this step la is completed, and no deceleration control processing is performed. Now, such a straight running state is performed during mowing work or simply when traveling, but when this is finished and the turning running state is entered, the operation flow shifts from step 1 to step 2. Such a state corresponds to a state in which, in an actual field, the combine harvester finishes mowing to the edge of the field and enters a turning position. Conventionally, before entering this turning state, skilled workers such as rental companies would reduce the accelerator setting of the work vehicle, which was still traveling straight, when the combine reached the headland. As a result, the engine speed dropped significantly when turning, causing problems.

Accordingly, in the present application, in step 2, the straight running engine rotation speed (Rx) of the combine is compared with a value obtained by adding a margin value (I) to a reference target value (Ri). If the rotational speed (Rx) is low, the process moves to step 3, and if it is high, the process moves to step 4. Here, the above-mentioned standard target value (Ri) is a value that is considered to require deceleration when a load is applied when the engine is in the maximum output state, and the above-mentioned margin value (I) is a value that is considered to require deceleration when the engine is in the maximum output state. This is the empirical value of the rotation speed, which is the margin between the engine rotation speed when the engine is considered to be in good operating condition based on the engine noise etc. when driving straight ahead, and the rotation speed that is actually allowed for the engine. In this state, the straight-line driving engine rotation speed (Rx) that causes the transition to step 3 means that the accelerator setting was used at a low value in the straight-line driving condition described above, and the straight-line driving engine speed that causes the transition to step 4 Traveling engine rotation speed (R
x) means that the accelerator setting was good and the engine was used with sufficient power in the straight-ahead driving state. Therefore, in order to avoid unnecessary deceleration control processing when turning, it was decided to change the reference value as the deceleration processing setting value (X) for determining whether or not to perform deceleration control processing depending on the situation. That is, in step 3, the value obtained by subtracting the margin value (I) from the straight-ahead running engine speed (Rx) is selected as the deceleration processing setting value (X), and if the current engine speed (R) is lower than this value The deceleration control process in step 5 is performed only when the value is high, and this process is not performed if the value is high. In addition, in step 4, the commonly used reference target value (Ri) described above is selected as the deceleration processing setting value (X), and if the current engine speed (R) is lower than this, step 5 is performed. A deceleration control process is performed, and if the value is high, this process is not performed. Therefore, in this control system, deceleration control processing during cornering is performed based on two values determined based on the engine rotational speed in normal driving conditions.

[Another Embodiment] In the above embodiment, a turning sensor serving as a turning detection means (S1) is provided at the base of the operating lever (I8), and the turning state is detected by detecting the position of this sensor. However, this may be manually operated by the operator.

Incidentally, although reference numerals are written in the claims section for convenient comparison with the drawings, the present invention is not limited to the structure shown in the accompanying drawings by the reference numerals.

[Brief explanation of drawings]

The drawings show an embodiment of the present application, and FIG. 1 is a mechanical diagram of a traveling system and a control system, FIG. 2 is a diagram showing an operation flow of a vehicle speed control means, and FIG. 3 is a side view of a combine harvester. (9)...Transmission, (E)...Engine, (31)...Turning detection means, (S2
)...Engine rotation detection means, (100)...
...Vehicle speed control means.

Claims (1)

[Claims] 1. The transmission (9) installed in the driving system is connected to the engine (E
), and further includes a vehicle speed control means (100) for decelerating the transmission (9), and a turning detection means (S1) for determining whether the work vehicle is in a turning state; engine rotation detection means (S2) for detecting the engine rotation speed (R) of the working vehicle, the working vehicle is in the turning traveling state, and the engine rotation speed (R) is a deceleration processing setting value (X). In the vehicle speed control device for a work vehicle, the vehicle speed control means (100) operates when the vehicle speed becomes lower than (X
) is the vehicle speed control device for a work vehicle. 2. The vehicle speed control means (100) controls the engine rotation speed (R) during cornering to a reference target value (Ri).
) and the margin value (I), the value obtained by subtracting the margin value (I) from the engine rotation speed (Rx) before the turn is selected as the deceleration processing setting value (X). If the engine speed (R) during cornering is higher than the sum of the reference target value (Ri) and the margin value (I), the reference target value (Ri) is set as the deceleration processing setting value. The vehicle speed control device for a work vehicle according to claim 1, wherein the vehicle speed control device is selected as (X).