JPS644013B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automatic slip correction device for automatically eliminating slips during work of an earthmoving vehicle equipped with a working machine such as a blade or a bucket cart.

Normally, in earthmoving vehicles, when the load on working equipment such as blades becomes excessive during work such as dozing, the tracks or wheels often slip, which causes wear on the tracks and wheels and impedes work efficiency. This is the result.

In addition to the overload of the work equipment as mentioned above, the causes of slips are not limited to the road surface shape, the shape of the tracks or wheels, etc., but even when slips occur due to any factor, it is possible to eliminate them. There is a need to.

Conventionally, operators manually operate vehicles and work equipment based on comprehensive judgment in order to obtain the maximum amount of work with the minimum amount of slippage.

However, such manual operation not only requires considerable skill and labor, but also poses a major problem that must be solved if unmanned earthmoving vehicles are to be used.

Furthermore, when a slip occurs due to an overload on the work equipment, when the work equipment is corrected in the direction of reducing the load in order to eliminate the slip, if the correction action is not performed properly, the road surface that should be finished smooth This may result in unevenness occurring on the surface, etc., which may affect the desired leveling accuracy.

This invention was made in view of the above circumstances, and its main purpose is to prevent slips in earthmoving vehicles by enabling early prediction and detection of vehicle slips during earthwork work, and automatically eliminating the slips at that point by signal control. To provide an automatic correction device.

In order to achieve the above-mentioned main purpose, this invention automatically detects the operating status of the components of each part of the vehicle and the load of the work machine, and performs corrective operation of the vehicle and work machine under computer control based on the detection signal, thereby preventing slippage. The present invention is characterized in that it is possible to prevent slips from occurring or to eliminate slips early and reliably.

Another object of the present invention is to provide an automatic slip correction device for an earthmoving vehicle that not only improves vehicle performance but also greatly contributes to completely unmanned operation of the vehicle.

In order to solve the above-mentioned problems, the present invention provides (a) a device for automatically correcting the slip of an earthmoving vehicle equipped with a working machine such as a blade or a bucket and a hydraulic system for driving the working machine, and (b) ) Providing a sensor to detect the load of the work equipment during earthwork work, (c) Providing a sensor to detect the operating status of the vehicle power transmission system components, (d) Providing a sensor to detect the operating status of the vehicle's power transmission system components, (d) is provided with a slip control device that outputs a work equipment control command signal and a vehicle traction force control command signal when a vehicle slip occurs or when the occurrence is predicted; (e) a work equipment control command signal is input from the slip control device; and (f) providing a traction force control means for inputting a traction force control command signal from the slip control device to control the power transmission system of the vehicle. We are taking appropriate measures.

Hereinafter, preferred embodiments of the present invention will be described based on the drawings.

In the illustrated wheeled earthmoving vehicle 1, the power transmission system includes a power transmission system in which power from an engine 2 is transmitted via a variable displacement torque converter 3 and a transmission 4 to an output shaft 5, and from the output shaft to a differential gear. It has a well-known configuration in which the power is transmitted to the left and right axle shafts 7 and 8 and both left and right wheels 9 and 10 via the shaft 6.

The vehicle 1 is equipped with a bucket 11 as a working machine in the illustrated example.

The bucket cart 11 is driven by hydraulic cylinders 12 and 13 for lifting and tilting.

Each of the hydraulic cylinders 12 and 13 is selectively operated by being supplied with pressure oil from a hydraulic system (not shown) provided in the vehicle 1 via an electromagnetic control valve or the like.

The vehicle 1 is equipped with sensors 15 to 18 for detecting the work machine load during earthwork work, and sensors 19 to 24 for detecting the operating status of each component of the power transmission system.

In the illustrated example, the sensors 15 to 18 for detecting the load on the work machine are tilt system pressure sensors 15 and 16 for individually detecting each hydraulic pressure on the head side and bottom side of the tilt hydraulic cylinder 13, and the same on the lift cylinder 13. It consists of lift system pressure sensors 17 and 18 that detect the oil pressure on the head side and bottom side of the hydraulic cylinder 12.

On the other hand, in the illustrated example, the sensors 19 to 24 of the power transmission system are the rotation speed detection sensor 2 of the engine 2.
4, a transmission torque level detection sensor 23 of the torque converter 3, a speed stage detection sensor 22 of the transmission 4, a vehicle speed sensor 21 that detects the rotation speed of the output shaft 5, and an axle illustrated as an example of a left and right drive system. A pair of left and right slip sensors 2 that individually detect the rotation speed of the shafts 7 and 8.
It consists of 0,19.

The respective output parts of the sensors 15 to 24 are connected to an input device 25A of a microcomputer (hereinafter abbreviated as microcomputer) 25 used as a slip control device.

The microcomputer 25 includes a CPU and memory (both not shown) in addition to the input device 25A and output device 25B.
The memory is preprogrammed with reference data for setting the operating conditions of the vehicle 1, the working position of the bucket 11, etc., or an operation control signal from an operator is input thereto.

Further, the microcomputer 25 includes a display device 26 for displaying input information from each of the sensors 15 to 24 and control command information as a result of information processing based on the input information.

Furthermore, the output device 25B of the microcomputer 25 is connected to the tractive force control means 27 and the working machine control means 28 of the vehicle 1.

When the bucket cart 11 is displaced and maintained at a predetermined working position while the vehicle 1 is traveling forward, earthwork work such as loading earth and sand is performed using the bucket cart.

Since the wheeled earthmoving vehicle 1 used during the work has the differential 6 as described above,
If a traction load occurs on the wheels 9, 10 and exceeds the limit of ground resistance, it is extremely rare that both wheels 9, 10 start to slip together. Therefore, in this case, a rotation difference occurs between both wheels 9 and 10.

The difference in rotation is determined by the slip sensors 19 and 20 detecting the respective rotational speeds of the axle shafts 7 and 8. The microcomputer 25 takes in the detection information and predicts the occurrence of a slip.

At the same time, the microcomputer 25 controls the other sensors 15.
It also incorporates information from ~18 and 21-24.

The microcomputer 25 processes and judges the input information from the sensors 15 to 24, and transmits the resulting control command signals to the traction force control means 27 to the working machine control means 28.

That is, the microcomputer 25 determines the cause of the slip by processing the input information from the sensors 15 to 24.

For example, if the cause is an overload on the bucket 11, the microcomputer 25 executes processing corresponding to the information from the work equipment load detection sensors 15 to 18 in order to reduce the load, and sends the resulting control command signal to this If so, it is transmitted to the work machine control means 28.

The means 28 automatically controls the hydraulic pressure of the hydraulic cylinders 12 and 13, the pump discharge pressure, the drive pressure of the hydraulic motor, the stress of the bucket 11, etc. in the hydraulic system for driving the work machine by inputting the control command signal described above. Control.

Through this control, the bucket 11 is operated to correct the load in the direction of reducing the load. Therefore, slips caused by the load on the work machine are automatically eliminated at an early stage.

On the other hand, if the cause of the slip is other than the work machine load, such as road surface conditions, the control command signal from the microcomputer 25 is transmitted to the traction force control means 27.

The means 27 automatically controls the fuel injection amount of the engine 2, the transmission torque level of the torque converter 3, the speed stage of the transmission 4, etc. based on the input signal.

Since the traction force of the vehicle 1 is automatically corrected, slips caused by road surface conditions other than the load on the work equipment are also automatically eliminated.

Therefore, even if a slip occurs due to any cause, it can be automatically resolved at an early stage.

Although the above is a case of a wheeled earthmoving vehicle, it goes without saying that the present invention can also be implemented in a tracked earthmoving vehicle.

However, there are some differences in the slip detection means between the wheeled type and the crawler type.

In other words, in the case of a track-type earthmoving vehicle in which the left and right tracks are driven individually by hydraulic pressure, there is a difference in ground resistance (traction coefficient) between those in which slip occurs in the left and right tracks and those in which slip does not occur. the result,
A change occurs in the motor drive pressure of the left and right drive hydraulic systems. Furthermore, if a slip occurs when the left and right tracks are driven individually, the vehicle attitude changes to either the left or the right.

That is, even if one crawler belt slips and spins, the opposite crawler belt continues to drive (rotate), so that the vehicle turns in either the left or right direction with respect to the direction of travel. This is true even if the vehicle is a wheeled type, but in particular, since a track type vehicle does not have a differential gear in order to maintain straight-line performance, the above-mentioned change in the vehicle's attitude clearly appears.

Therefore, it is sufficient to detect this change in the vehicle posture.

Therefore, in the case of a track-type earthmoving vehicle, slip detection means include the pump discharge pressure of the left and right track drive hydraulic systems, motor drive pressure, motor torque, etc.
The driving force of the left and right tracks may be detected by a pressure sensor, and the vehicle attitude may be detected by a geomagnetic sensor, a gyro compass, etc. provided in the vehicle itself. Other information detection, information processing, control commands, etc. are basically the same as in the case of the wheeled vehicle described above, so their explanation will be omitted.

Therefore, slips can be automatically eliminated in the case of a tracked earthmoving vehicle as well as in the case of a wheeled earthmoving vehicle.

As described above, the present invention automatically detects the operating status of power transmission system components and the load of the work machine during work on an earthmoving vehicle, and uses a control command signal as a result of processing the detected information by a computer to control the operation of the vehicle when a slip occurs. Since the traction force control and the corrective operation of the work equipment are carried out, it is possible to quickly and automatically eliminate vehicle slippage during earthwork work.

Therefore, according to the present invention, it is possible to eliminate all the problems caused by slipping of earthmoving vehicles,
In addition to improving vehicle performance, there are many other benefits such as no manual operation required to control traction force or correct work equipment when a slip occurs, greatly contributing to unmanned operation of earthmoving vehicles.

[Brief explanation of drawings]

The drawing is a system block diagram of an automatic slip correction device according to a preferred embodiment of the present invention. 1 is an earthmoving vehicle, 2 to 10 are power transmission system components of the vehicle, 11 is a bucket exemplified as a working machine, 12 and 13 are hydraulic cylinders of a hydraulic system for driving the working machine, 15 to 18 are sensors for detecting the load of the working machine, 19 to 24 are component type sensors, 2
5 is a microcomputer, 27 is a traction force control means, and 28 is a work machine control means.

Claims (1)

[Scope of Claims] 1. A device that automatically corrects the slip of an earthmoving vehicle equipped with a working machine such as a blade or bucket and a hydraulic system for driving the working machine, and detects the load of the working machine during earthwork work. A sensor detects the operating status of the vehicle's power transmission system components, and detects information signals from these sensors, and performs information processing based on the input signal to perform work when a vehicle slip occurs or when the occurrence is predicted. a slip control device that outputs a machine control command signal and a vehicle tractive force control command signal; and a work machine control means that inputs the work machine control command signal from the slip control device to correct the work machine in a direction to reduce the load. An automatic slip correction device for an earthmoving vehicle, comprising: a traction force control means for controlling a power transmission system of the vehicle by inputting a traction force control command signal from the slip control device. 2. The automatic slipper for an earthmoving vehicle according to claim 1, wherein the sensor for detecting the load on the working equipment is a pressure sensor that detects the hydraulic pressure of the hydraulic system for driving the working equipment during earthwork work. correction device. 3 Sensors for power transmission system components include sensors that individually detect the engine rotation speed, torque converter transmission torque level, transmission speed stage, and torque converter output shaft rotation speed, and sensors that detect the rotation speed of the left and right drive systems. 2. The automatic slip correction device for an earthmoving vehicle according to claim 1, further comprising a slip sensor for detecting changes in driving force or vehicle posture in the left-right direction. 4 The slip control device is composed of a microcomputer, which inputs or stores reference data for setting vehicle operating conditions and work equipment working positions, and compares and calculates the reference data with input information from each sensor. 2. The automatic slip correction device for an earthmoving vehicle according to claim 1, wherein the device is configured to output appropriate control signals for the vehicle and the working machine. 5. The earthmoving vehicle according to claim 1 or 4, wherein the slip control device includes a display device that displays input information from each sensor and control command information as a result of information processing. automatic slip correction device. 6. The work machine control means controls the hydraulic pressure of the hydraulic cylinder in the work machine drive hydraulic system, the pump discharge pressure, the drive pressure of the hydraulic motor, the work machine stress, etc. based on the input signal from the slip control device. An automatic slip correction device for an earthmoving vehicle according to claim 1, characterized in that: 7. A patent claim characterized in that the traction force control means controls the fuel injection amount of the engine, the transmission torque of the torque converter, the speed gear of the transmission, etc. based on the input signal from the slip control device. An automatic slip correction device for an earthmoving vehicle according to item 1.