JPS6026727A - Working vehicle with slewing base - Google Patents

Abstract

PURPOSE:To prevent the unexpected slewing of a working machine by sending a warning at the time of non-setting relation by providing a comparator circuit to detect whether or not the operation input signal and the operation output signal of the drive power source circuit of a solenoid proportion valve set to a slewing oil-pressure circuit are in a setting relation. CONSTITUTION:A control valve 9 and a solenoid proportion valve 28 are provided a slewing oil-pressure motor 3 and an oil-pressure pump 8. A sensor 13 and a stop position setter 14 for a slewing base 2 and an operation detector 15 for the control valve 9 are also provided. The solenoids 18a and 18b of pilot valves 11a and 11b provided to a pilot circuit to drive the valve 28 are controlled by a power source circuit 19. Also, a comparator circuit 25 to detect whether or not the input and output signals of the power source circuit 19 are in setting relation is provided, and an alarm 27 is actuated when they are not in setting relation. Unexpected slewing of working machine due to the electrical trouble of the control circuit of the valve 28 can thus be prevented.

Description

[Detailed description of the invention] The original F! A is provided with a hydraulic motor for driving the swivel base, a valve that switches the operating state of the motor, and an electromagnetic proportional valve that continuously adjusts the amount of oil supplied to the hydraulic motor, and also controls the rotational position of the swivel base relative to the vehicle body. The swivel base includes a device that sets the rotational position relative to the vehicle body at which the swivel base should stop, and a device that detects the operating state of the switching valve. A control mechanism is provided to automatically operate the electromagnetic proportional valve to the flow rate decreasing side before reaching the set rotational position relative to the vehicle body while the rotating base is rotating toward the rotational position. In order to automatically stop the swivel at a certain position, the swivel base is rotated at high speed during rotation to improve work efficiency, but at the end of the rotation, the rotation speed of the swivel base is slowed down and the swivel base is stopped. This invention relates to a work vehicle equipped with a swivel platform that allows operations to be carried out without receiving shocks.

Conventionally, in the above-mentioned work vehicle with a swivel platform, there have been cases where the electromagnetic proportional valve does not operate normally despite the operation signal being transmitted due to trouble in the drive power supply circuit for the electromagnetic proportional valve. If it did not operate to reduce the flow rate, the swivel table would not be decelerated and would overshoot the set stop position, which could lead to an unexpected accident.

In view of the above-mentioned actual situation, an object of the present invention is to prevent unexpected operational troubles of the swivel table caused by electrical troubles in the drive power supply circuit for the electromagnetic proportional valve by improving the automatic operation circuit. The characteristic structure of the above-mentioned work vehicle with a rotating platform includes a comparison circuit for detecting whether or not the operation input signal of the drive power supply circuit for the electromagnetic proportional valve and the operation current have a set correspondence relationship, and the comparison circuit An alarm device is provided which is activated when the set correspondence relationship is deviated from, based on information from the above, and its functions and effects are as follows.

In other words, 1! means that the operation input signal and the operation current deviate from the set correspondence relationship. A warning device can quickly make the operator aware of troubles in the drive power circuit detected by separating the electrical troubles, and can prevent unforeseen situations such as overrun of the swivel table due to electrical troubles. As a result, the safety of automatic swivel base operation can be greatly improved.

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

As shown in Fig. 1, a pair of left and right Taro-2 traveling devices fi
A swivel base (2) is attached to a machine base equipped with a hydraulic motor (3) so as to be freely swivelable by a hydraulic motor (3), and the swivel base +21K, a boarding operation section (4), and a driving section (5) are provided,
An excavation work device is constructed by connecting an excavation baguette (7) to a work arm (6) which can be vertically swung and can be bent and extended, and is connected to a swivel base (2) to constitute an excavation work vehicle.

As shown in Figure 2, hydraulic motor (3) and pump (8)
A pilot pressure is provided in the oil path connecting the motor (3) to forward/reverse rotation and to stop the motor (3), and to continuously throttle and adjust the amount of oil supplied to the motor (3) in each of the forward rotation state and the reverse rotation state. An operable proportional switching valve (9) is installed, and the spool of the switching valve (9) can be slid in a stepless manner to change its position in cooperation with a neutral biasing spring (10) attached to it. A pair of electromagnetic proportional one operation type (that is, proportional control) +7) first and second pilot valves (lla
), (llb) are provided so that the pressure oil from the pump (8), which is diverted from the brake mechanism, is used as oil pressure oil.

In other words, those pilot valves (lla), (1lb
) is configured to perform forward/reverse switching and stopping operations of the swivel base (2), as well as a swivel speed control operation, by electromagnetic operations.

As shown in FIG. 8, a sensor (13) for detecting the rotational position of the swivel base (21) relative to the vehicle body is provided on the rotating shaft portion of the swivel base (2), and device (14a) = (14b) for setting the position, and the switching valve (9)
) is provided with a device (151) for detecting the switching state of the
Those sensors (IJ, setting device (14a, L (14b)
) and based on the information from the detection device (Is), in order to stop the swivel base (2) at the set rotational position relative to the vehicle body, the amount of oil supplied is changed (9) before reaching the set rotational position relative to the vehicle body. The eleventh and second pilots fF (lla) and (lla) are operated to the decreasing side and to the neutral stop position.
A controller (14a) with a built-in microcomputer is provided to automatically control (b) a controller (14a) with a built-in microcomputer that automatically controls each stop position of the reciprocating rotation in order to control the rotation operation that is repeatedly performed to release the excavated earth and sand to a predetermined position. ), (14b)
The switching valve (9) is configured with a proportional valve so that the switching valve (9) can be easily activated by simply starting the swivel base under the conditions set separately for each of the swivel bases (2) and 3).
By controlling the amount of oil supplied to the
It is constructed so that the rotational speed during turning is increased to improve work efficiency and efficiency, and the rotating table (2) can be smoothly decelerated and stopped without impact.

In the figure, (+71) is used to manually switch the switching valve (9) to give priority to automatic swing control, to control the flow rate, and to operate the swing base (2) before starting up during self-help swing operation. It is a human operating device.

The electromagnetic proportional operation type pilot valve (11aI).

(llb), the first and second
Electromagnetic solenoids (18a), (18b) for operating the pilot valves (lla), (llb), each with a separate first. The second drive power circuit (19a), (19b) is connected to the microcomputer (16a) built in the controller port 0.
/Aim circuit ■ and direction 1'lJ switching circuit +21
) are connected in series, and a microcomputer (
The voltage value signal as a speed signal transmitted from the microcomputer (16a) via the D/A conversion circuit (2) is determined and switched based on the l-Qw-HIGH direction signal also transmitted from the microcomputer (16a). The circuit CD is configured to selectively switch and transmit the signal to the first and second drive power supply circuits (19a) and (19b). In other words, the switching valve (9)
The actuation speed of the actuator is proportionally indicated by a speed signal, and the actuation direction is selectively indicated by a direction signal.

First and second drive power supply times fil! r (19a), (19
b) & corresponding electromagnetic solenoid (18a),
(18b) between the first and second operating current detection circuits (
22a) and (22b) are separately interposed, and the first and second operating current detection circuits (22a) and (22b)
) Ic, first and second current comparators (23a) that convert these detection operation currents into LOW-HIGH signals, (
zab), and also a voltage comparator ta is installed to convert the voltage value signal from the D/A conversion circuit into a LOW-HIGH signal.

And Microkon Byouk (16a) Kara 77)
Direction signal and first and second current comparators (28a) @
The electromagnetic solenoid (18a) on the side instructed to operate by the direction signal is compared with the signal from C28b).

A first comparison circuit (25a) is provided to detect whether or not the electromagnetic solenoid (18b) is in an energized state and the other electromagnetic solenoids (18b) and (18a) are in a de-energized state. and *X% signals from the second current comparators (28a) and (28b),
When a speed signal is being transmitted, whether or not one of the electromagnetic solenoids (18a) and (18b) is in a magnetic state is determined at 31, and when a speed signal is not being transmitted, both electromagnetic solenoids (18a) and (18b) are in a magnetic state. ) and (18b) are both in the dream excitation state. ! J2 comparison circuit (2
5b), thereby providing the first and second drive power supply circuits (19
Due to the troubles in a) and (19b), each electromagnetic solenoid (18a) and (18b) did not operate according to the instructions of the microcomputer (16a) in either or both of the speed signal and direction signal. 1. Second comparison circuit (25a).

Based on the information from (25b), the alarm circuit (2) is activated, and in the hydraulic circuit, the safety stop valve (27a) installed in series with the switching valve (9) is closed and activated. ) is brought to an emergency stop, and the alarm update (27b
) and a warning lamp (27c).

In addition, a device a5V for detecting the operating state of the switching pulp (3)
i. Instead of directly detecting the switching state of the pulp (9), for example, the rotation of the swivel base (2) is based on information from a sensor f13 that detects the position of the swivel base (2) relative to the vehicle. The operation state of the pulp (9) may be indirectly detected by detecting the direction.

In addition, as described above, while the switching valve (9) is also used to switch between forward and reverse rotation of the swivel base (2), the amount of oil supplied can be adjusted from the first and second pilot valves (lla) and (llb). Instead of configuring the electromagnetic proportional valve (■) for use in the hydraulic system, an electromagnetic proportional valve for adjusting the amount of oil supplied may be provided as a separate device from the switching valve (9), and various improvements can be made to the specific hydraulic circuit structure. De-ru.

Furthermore, the electromagnetic proportional valve (driving power supply times w for 281vc)
! Various improvements can be made to the specific circuit configuration of the comparator circuit that detects whether or not the operating input signal of the rus and the operating current have a set correspondence relationship. The safety stop valve (
soya), alarm buzzer-C27b), alarm lamp (2
Various improvements are possible, such as using only one of 7c) or using other alarm devices.

The present invention is directed to various types of work vehicles with swivel platforms, such as excavation work vehicles and crane work vehicles.

[Brief explanation of the drawing]

The drawings show an embodiment of a working vehicle with a swivel platform according to the FIAVc of the present invention, in which Fig. 1 is an overall side view, Fig. 2 is a hydraulic circuit diagram, and Fig. 8 is a hydraulic circuit diagram.
The figure is a control system diagram. (2)...Swivel base, (3)...Hydraulic motor, (3)...Switching pulp, IL...
・Rotational position detection sensor, (14a) + (14b)...
... Setting device, (151... Operation state detection device, (le... Control mechanism, (1鵠...
・Drive power supply circuit, ■・・・Comparison circuit, fixed...
・・Warning device is in trouble・・・Solenoid proportional valve.

Claims (1)

[Claims] A hydraulic motor (3) for driving the swivel table, a valve (9) for switching the operating state of the motor (3), and an electromagnetic proportional valve for continuously adjusting the amount of oil supplied to the hydraulic motor (3) are provided. In addition, a sensor f13 for detecting the rotational position of the swivel base (2) relative to the vehicle body, and a device (14a) or Vi (14) for setting the rotational position relative to the vehicle body at which the swivel base 21 should be stopped.
b) and the device 09 that detects the operation state of the switching valve (9).
) is rotating toward a set rotational position relative to the vehicle body, a control mechanism (1
61, the control mechanism (161) determines whether or not the operation input signal of the drive power supply circuit fil and the operation current for the electromagnetic proportional valve (branch) have a set correspondence relationship. A work vehicle with a swivel platform is provided with a comparison circuit (2) for detection, and an alarm device that is activated when the set correspondence relationship is deviated based on information from the comparison circuit (E).