JPS6352330B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a working device that can freely change its attitude with respect to a vehicle body, and is provided with a sensor that detects a change in its attitude relative to the ground, and the attitude of the working device relative to the ground is adjusted to a set attitude based on information from the sensor. The present invention relates to a working device posture maintaining device for a working vehicle that is provided with a control device that automatically operates a vehicle body posture correcting device to maintain the posture of a working vehicle.

Conventionally, in the posture maintenance device for the above-mentioned work equipment,
In order to prevent erroneous detection by the sensor due to vibrations of the work equipment, which would impair the stability of posture correction control, for example, if the sensor is configured as a weight type, the swing of the weight should be A predetermined initial resistance may be applied to the sensor, or a filter device may be interposed between the sensor and the control device to remove instantaneous signals caused by vibrations of the working equipment from among the signals emitted from the sensor. However, in any case, since the dead zone of the sensor is increased, the detection sensitivity of the sensor is greatly reduced, and as a result, the attitude correction control performance is significantly reduced in terms of accuracy. It was hot.

In view of the above-mentioned circumstances, it is an object of the present invention to rationally improve the information processing circuit from the sensor, while maintaining high accuracy of the posture correction control performance, while reducing control instability caused by the detection of vibrations of the working equipment. The goal is to be able to effectively prevent this.

The characteristic structure of the working equipment posture maintaining device according to the present invention is that, in the above-mentioned working vehicle, the sensor has a weight that is swingably suspended, and the sensor is selected by the weight as the working equipment swings from the set posture. The control device includes two switches that can be turned on or off at the same time, and the control device includes an integrating circuit for two types of voltage signals sent in response to the selective operation of the switches, and The present invention includes a circuit that determines the direction in which the attitude of the working device relative to the vehicle body should be corrected based on the obtained integral value, and its functions and effects are as follows.

In other words, the two types of signals from the sensor, including the signal due to the vibration of the work equipment, are integrated, and the direction of the attitude correction of the work equipment is determined based on the integrated value, so the attitude correction control is effective regardless of vibration detection. Furthermore, since there is no need to set up a large dead zone to ignore signals caused by vibrations as in conventional configurations, the detection sensitivity of the sensor can be maintained at a good level. The accuracy of the correlated attitude correction control can be maintained extremely high, and as a whole, it has become possible to provide an attitude maintenance device that is excellent in both control stability and accuracy and has great practical effects.

Next, embodiments of the present invention will be described in detail based on illustrative drawings.

As shown in FIG. 1, a swivel base 2 is attached to a machine base equipped with a pair of left and right traveling devices 1, and a boarding and driving section 3 and a driving section 4 are provided on the swivel base 2.
An excavation bucket 6 is attached to the tip of a working arm 5 connected to the swivel table 2 and is capable of vertically swinging and bending/extending operation, so as to be able to swing freely around the horizontal axis Q using a hydraulic cylinder 7. has been configured.

As shown in FIG. 2, the three-position switching operation valve 8 for the bucket hydraulic cylinder 7 is configured as a proportional valve that can adjust the amount of pressure oil supplied to the cylinder 7, and the operation valve 8 is switched by pilot pressure. A pair of electromagnetic proportional pressure reducing valves 9a, 9b are provided for operation and proportional control operation, and these electromagnetic proportional valves 9a,
By operating the drive controller 10 for the drive controller 9b, a bucket operation is performed.

Then, a weight type sensor 11 is attached to the bucket 6 to detect changes in its rocking attitude relative to the ground, and based on the information from the sensor 11, the attitude of the bucket 6 relative to the ground is maintained at a preset soil holding posture. The drive controller 10
A control device 12 is provided to automatically operate the work arm 5, and when the bucket 6 holding excavated soil is moved from the excavation site, the posture of the working arm 5 can be changed by simply starting the automatic control device 12. Accordingly, the attitude of the bucket 6 relative to the vehicle body is automatically corrected, and the structure is configured such that the attitude relative to the ground can be continuously maintained at an appropriate soil holding attitude.

The sensor 11 is connected to the swing axis Q of the bucket 6.
A weight 13 is suspended so as to be swingable around an axis P parallel to the bucket 6, and the bucket 6 comes into contact with the weight 13 as it swings from the set position, so that the bucket 6 can be selectively entered and operated. , a pair of limit switches 14a, 14b fixed to the bucket 6 side and distributed in the swinging direction of the weight 13, and when the limit switches 14a, 14b are selectively turned on, the limit switches 14a, 14b are turned on. Based on the circuit 12a that continuously integrates the side voltage signals separately transmitted from 14b and the equivalent side voltage signals in a set time unit, and the integral value obtained by the integrating circuit 12a,
The control device 12 is equipped with a determination circuit 12b that specifies the direction of correcting the attitude of the bucket 6 relative to the vehicle body on the side where the calculated integral value becomes 0, and the cylinder 7 for the bucket 7
is configured to automatically operate in the direction designated by the determination circuit 12b and at a speed proportional to the absolute value of the integral value calculated by the integrating circuit 12a.

In other words, by integrating the two types of voltage signals from the sensor 11, the sensor 1
The control accuracy is improved by making the dead zone of 1 as small as possible.

In addition to the bucket truck 6, various work devices such as a crane device can be used as the target device for correcting the vehicle body posture according to the present invention.

In addition, various types of drive devices such as hydraulic type and electric type can be applied as specific drive devices for changing the attitude of the working device 6, and these drive devices are collectively referred to as the attitude toward the vehicle body. It is called a correction device 7.

Furthermore, various improvements can be made to the specific circuit configurations of the integrating circuit 12a for the two types of voltage signals transmitted from the sensor 11 and the circuit 12b for determining the direction of correcting the attitude of the working device 6 relative to the vehicle body based on the integrated value. In addition, the two switches 14a and 14b that are selectively engaged or switched by the weight 13 in the sensor 11 may be of various types, such as using a pressure sensitive element instead of using a limit switch. It is possible to apply a switch.

[Brief explanation of the drawing]

The drawings show an embodiment of the working device posture maintaining device for a working vehicle according to the present invention, and FIG. 1 is an overall side view of the working vehicle, and FIG. 2 is a schematic control system diagram. 6... Working device, 7... Vehicle attitude correction device,
11...sensor, 12...control device, 12a...
...integrator circuit, 12b...judgment circuit, 13...wait, 14a, 14b...switch.

Claims (1)

[Claims] 1. A working device 6 that can freely change its posture with respect to the vehicle body,
A sensor 11 is provided to detect a change in the ground attitude, and a control device 12 is provided to automatically operate the vehicle attitude correction device 7 to maintain the ground attitude of the working device 6 at a set attitude based on information from the sensor 11. In the working vehicle, the sensor 11 is selectively engaged or disengaged by a weight 13 that is swingably suspended, and the weight 13 is selectively operated by the weight 13 as the working device 6 swings from a set posture. The control device 12 includes an integrating circuit 12a for two types of voltage signals sent in response to an alternative operation of the switches 14a, 14b, and the circuit 12a. A working device posture maintaining device for a working vehicle, comprising a circuit 12b that determines a direction of correcting the posture of the working device 6 relative to the vehicle body based on the obtained integral value.