JPH03149452A - Car speed controller of working car - 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 includes an engine load detection means for detecting the load state of the engine, and a speed change system based on information from the engine load detection means so as to reduce the vehicle speed when the engine load becomes large. The vehicle speed control device of a working vehicle is equipped with vehicle speed control means for automatically decelerating the device. [Prior Art] The vehicle speed control device for this type of work vehicle described above has the risk of stalling when the load on the engine increases.
When the engine load exceeds a set value, it automatically decelerates to reduce the engine load.
. By the way, to set the above setting values, take advantage of the fact that the engine speed is not changed during work, for example,
The setting value for determining the magnitude of the load during work is determined based on the load state of the engine when the work equipment is in a non-operating state and immediately before switching to the work state. [Problems to be Solved by the Invention] By the way, even when not working, when the vehicle body is turned to move between work strokes, if the running ground condition is poor and the running load is large, Even when the equipment is in a non-operating state, the engine load may increase and the engine may stall. Therefore, it is desirable to be able to automatically decelerate when the engine load increases even when the engine is not working, but it has been difficult to determine a set value for determining the magnitude of the load during work. In other words, when the engine is not working, the driver often changes and sets the engine speed, so it is not possible to determine the set value for non-working. The present invention has been made in view of the above-mentioned circumstances, and its purpose is to enable accurate automatic deceleration when the load increases even during non-work. [Means for Solving the Problems] A vehicle speed control device for a work vehicle according to the present invention includes an engine load detection means for detecting the load state of the engine, and a device for controlling the engine load so as to reduce the vehicle speed when the engine load becomes large. A vehicle speed control means for automatically decelerating the transmission based on information from the load detection means is provided, and its characteristic configuration is as follows. That is, a working state detecting means is provided for detecting whether the vehicle is working or not, and the vehicle speed control means determines whether the value of the engine load is low during working based on information from the working state detecting means. The present invention is configured to perform a deceleration operation when the rate of increase in the engine load is greater than a set value, and to perform a deceleration operation when the rate of increase in the engine load is greater than the set value during non-operation.

[For use]

In other words, during work, the engine load is determined based on whether or not the engine load is greater than the set value, that is, whether or not to decelerate the engine load, and during non-work, the engine load is determined based on the rate of increase in the engine load. By determining the magnitude, it is possible to accurately determine an increase in load even if the engine speed is changed during non-operation. [Effects of the Invention] As a result, it has become possible to accurately automatically decelerate when the load increases both during work and non-work. [Example] Hereinafter, an example in which the present invention is applied to a combine harvester as a working vehicle will be described based on the drawings. As shown in Fig. 5, a combine harvester has a machine body (2) equipped with a pair of left and right crawler running devices (1), and a threshing device (3) as a working device mounted on the machine body (2). A boarding control section (4) is provided, and a reaping section (5) as a working device is provided on the front side of the boarding control section (4) so as to be movable up and down. In the figure, (6) indicates the reaping part (
5) is a hydraulic cylinder for lifting. During the transport route of the reaped grain culm in the reaping section (5), the switch contacts the base of the reaped grain culm and is turned on when the transport grain rod is present, and is turned on when the transport grain rod is absent. The stock sensor (S0
) is provided. In other words, this stock sensor (S0)
corresponds to the work state detection means for detecting whether the work is in progress or not. As shown in FIG. 1, the crawler traveling device (1) includes:
The hydraulic continuously variable transmission (7) is configured to be driven by the output of a hydraulic continuously variable transmission (7) driven by an engine (E), and the hydraulic continuously variable transmission (7) is driven by a speed change electric motor ( 8) allows for automatic reproduction. However, the hydraulic continuously variable transmission W (7) is interlocked and connected to the speed change lever (9) provided in the boarding control section (4) so that it can be operated manually, and In order to be able to give priority to the operation by the electric gear shifting motor (8), the electric gear shifting lever (9) is connected to the hydraulic continuously variable transmission (7) in a linkage path between the gear shifting lever (9) and the hydraulic continuously variable transmission (7). A motor (8) is linked via a frictional transmission (10). In the figure, (1l) is a transmission case for the crawler traveling device (1). Based on the engine rotation speed detection sensor (S0) that detects the rotation speed of the engine (E) and the input rotation speed from the hydraulic continuously variable transmission (7) to the transmission case (M). A vehicle speed sensor (S2) as a vehicle speed detection means for detecting vehicle speed, and these sensors (S+) and (SZ)
Based on the information of and the information of the stock sensor (S0),
The load condition of the engine (E) is determined, and the electric motor for speed change (8) is controlled to control the hydraulic continuously variable transmission (
7) A microcomputer-based control device (11) constituting a vehicle speed control means (Zoo) that automatically decelerates the vehicle.
and is provided. By the way, when the load on the engine (fE) increases, the rotational speed of the engine (fE) decreases in accordance with the increase in load, so during work, as shown in FIG.
The load state of the engine (E) is determined based on the deviation between the engine rotation speed detected by the engine rotation speed detection sensor (S8) and a preset set value, that is, the decrease in rotation speed (n) from the set value. This is to make it possible to determine the following. In other words, the engine rotation speed detection sensor (
S1) corresponds to the load state detection means for detecting the load state of the engine (E). However, the above-mentioned reduced rotational speed (n
) is the set value (n0) for the engine (E).
Set value (for example, 1
10 rpm) is set to a lower value. To explain, the reference rotation speed is the detected value of the rotation speed detection sensor (S0) at the time when the combine harvester enters the planted culm group from the headland and the stock sensor (S0) is turned on. Set based on On the other hand, during non-work, as shown in Figure 4, if the deviation between the previously detected engine speed and the currently detected engine speed, that is, the speed decrease rate (N), becomes larger than the set value (N1). , the deceleration speed is increased as the rotational speed reduction rate (N) increases. In other words, the rate of decrease (N) in the engine speed increases as the engine load increases rapidly, so that the more rapidly the load increases, the faster the engine speed is decelerated so that the load can be reduced quickly. Next, the operation of the control device (11) will be explained based on the flowchart shown in FIG. As the control operation is started, the stock sensor (S0
) is used to determine whether the machine is working or not. When the engine is not working, compare the rotation speed reduction rate (N) with the set value for non-working (Nl) to determine the load state of the engine ([!) during the non-working period. , and if the work is in progress, the reduced rotational speed (n) is compared with the work setting value (n1) and the engine (
The load condition of E) will be determined. First, control when the machine is not working will be explained. The rotation speed reduction rate (N) is the non-working setting value (N1)
If the load is higher than that, it is determined that the load is large and a deceleration operation is performed, and if it is less than the non-work set value (N0), the current vehicle speed is maintained. However, when decelerating, as shown in Figure 4,
In order to perform rapid deceleration, the electric motor (8) is driven intermittently at a period (T ). T=C-N+B However, C and B are control constants. On the other hand, if the stock sensor (S0) is in the ON state and it is determined that work is in progress, the reduced rotational speed (n
) and the work set value (n1), and if the reduced rotational speed (n) is larger than the dead zone for the work set value (n0), a deceleration operation is performed. . However, as shown in Fig. 3, the deceleration speed during work is determined by the reduced rotational speed (n) and the work setting value (n0).
The cycle (T) of the intermittent drive of the electric motor (8) is determined in the same manner as the deceleration operation during non-working so that the deceleration operation is performed at a higher speed as the deviation from the motor (8) increases. Although I will not go into details, since the load characteristics on the engine (IE) are different when not working and when working, the control characteristics of the deceleration speed are changed between when not working and when working. As the engine (E) becomes larger, the margin for the maximum load of the engine (E) becomes smaller. Therefore, as the load becomes larger, it is necessary to reduce the load more quickly. Therefore, as the load becomes larger, the speed can be reduced more quickly. However, if the vehicle decelerates too much, there is a risk of the vehicle stopping, so the vehicle speed or set vehicle speed (V0
), the deceleration operation should be performed only when the value is greater than . During work, if the reduced rotational speed (n) is smaller than the dead zone for the work setting value <n0) and there is sufficient output from the engine (E), the engine (E) will automatically increase the output. It is also possible to reach. When performing a speed increase operation, similarly to the case of a deceleration operation during work, the speed increase increases as the deviation of the reduced rotational speed (n) from the work setting value (n0) increases. The intermittent drive cycle (T
) (see Figure 3). [Another Embodiment] In the above embodiment, a stock origin sensor (
Although we have exemplified the case where it is determined whether the machine is working or not based on the information of S0), for example,
It is determined whether the threshing device (3) is in operation or not in operation based on whether or not it is in a driving state, and whether the driving torque of the threshing device (3) is greater than a set value. It may be possible to determine whether the work is in progress or not based on whether the work is in progress or not, and the specific configuration of the work state detection means can be modified in various ways. Further, in the above embodiment, the load condition on the engine (E) is determined based on the engine rotation speed, but for example, the load condition is determined based on the output torque of the engine (E), etc. The specific configuration of the engine load detection means can be changed in various ways. Furthermore, in the above embodiment, the case where the speed increasing operation is also performed during work is exemplified, but it is also possible to perform only the decelerating operation, or even when the load is reduced even during non-work. The speed may be increased automatically. Furthermore, instead of the configuration in which the deceleration speed is controlled according to the magnitude of the load, the deceleration speed may be controlled according to the magnitude of the vehicle speed. In other words, the load on the engine (E) increases as the vehicle speed increases, and the greater the load, the more quickly the load needs to be reduced, that is, the faster the deceleration operation is required. good. Furthermore, the deceleration speed may be controlled based on both the amount or rate of decrease in the engine speed and the vehicle speed, and the specific configuration of each part, such as the specific configuration for setting the deceleration speed, may be changed in various ways. can. In addition, in the above embodiment, a case is illustrated in which it is always determined whether or not to decelerate, but for example, if the operator artificially changes the engine speed, the engine (E)
The deceleration may not be made until the output is stabilized. 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.

[Brief explanation of the drawing]

The drawings show an embodiment of the vehicle speed control device for a working vehicle according to the present invention, in which Fig. 1 is a block diagram of the control configuration, Fig. 2 is a flowchart of control operation, and Fig. 3 shows load conditions and deceleration speed during work. FIG. 4 is an explanatory diagram showing the relationship between the load state and deceleration speed during non-working, and FIG. 5 is a schematic side view of the front part of the working vehicle. (10)...Engine, (S0)...
Working state detection means, (S0)...Engine load detection means, (7)...Transmission device, (100).
...Vehicle speed control means.

Claims (1)

[Claims] The engine load detection means (S_1) detects the load state of the engine (E), and the engine load detection means (S_1) detects the load state of the engine (E).
A vehicle speed control device for a work vehicle, which is provided with a vehicle speed control means (100) that automatically decelerates the transmission (7) based on the information of 1), and is provided with a vehicle speed control means (100) that automatically decelerates the transmission (7) based on the information of (1), whether the vehicle is in operation or not in operation. The vehicle speed control means (100) detects whether the engine load value is lower than the set value during the work based on the information of the work state detection means (S_0). A vehicle speed control device for a work vehicle configured to perform a deceleration operation when the increase rate of the engine load is greater than a set value, and to perform a deceleration operation when the increase rate of the engine load is greater than a set value during non-work.