KR101298401B1 - Self-diagnostic emergency steering device for wheel loader - Google Patents

Abstract

The present invention relates to a self-diagnosis emergency steering device for a wheel loader, comprising a steering flow path (L1) for supplying hydraulic oil of a steering pump (Ps) to a steering cylinder (4a) via a priority valve (3) and a steering valve (4). ; An electric motor 7 selectively connected with the battery BAT; A first pressure switch (16) which is operated when the pressure in the branch flow path (L2) branched with the steering flow path (L1) is detected and is less than a set value; If the detection value is greater than or equal to the set value, the battery BAT and the electric motor 7 are shorted and the detected value is less than the set value. The battery BAT and the electric motor 7 are energized and the electric motor 7 is driven to supply hydraulic oil to the priority valve 3 through the emergency steering flow path Le to provide emergency steering. A controller 30; It is configured to include a self-diagnostic means provided to confirm whether the normal operation by operating the electric motor (7) temporarily, so that the emergency steering of the equipment as well as the normal operation of the emergency steering means for a set time automatically at start-up There is an effect that can ensure the safety and reliability.

Wheel Loaders, Emergency Steering, Inspection

Description

Self-diagnostic emergency steering device for wheel loader

1 is a circuit diagram showing an emergency steering system of a wheel loader according to the prior art.

2 is a circuit diagram showing a self-diagnosis emergency steering apparatus of a wheel loader according to the present invention.

<< Explanation of symbols for main part of drawing >>

3: priority valve 4: steering valve

4a: steering cylinder 7: electric motor

8: emergency steering hydraulic pump

15: emergency steering check valve 16, 17: pressure switch

20: emergency steering manual switch 30: controller

According to the present invention, when the engine is stopped by a fatal defect of the engine during operation of the machine, the emergency steering electric motor can be driven to form hydraulic pressure to temporarily steer, and the self-loading of the wheel loader that can provide self-diagnosis of the electric motor. Diagnostic emergency steering system.

In general, when the engine is stopped during normal operation, the wheel loader stops the supply of hydraulic pressure to all hydraulic circuits including the steering and stops the steering. In this case, the emergency steering system of the wheel loader according to the prior art of FIG. 1 has a pressure of the hydraulic oil to the steering flow path L11 supplied from the steering pump Ps to the emergency steering pressure switch 5 provided at the front end of the valve 3. If this is not detected, it is determined that the engine is off or not in normal operation.

As described above, if the emergency steering pressure switch 5 is turned off or is confirmed to be in a non-operational state (below a certain pressure), the emergency steering timer 6 is connected to the emergency line electrically connected by the signal line L20. The detection value (emergency steering) is input from the steering pressure switch 5 to supply electricity to the electric motor 7, and the hydraulic oil of the flow path L20 is driven through the emergency steering flow path L13 by the motor driving. By supplying to the steering cylinder 4a via the steering valve 4, the steering is temporarily realized. In this case, the emergency steering timer 6 performs a function of connecting a lamp function informing that emergency steering is necessary and a battery BAT connected to the electric motor 7.

However, the prior art having such a configuration has the advantage of temporarily evacuating the equipment to the safety shoes in case of emergency such as when the engine is stopped or normal operation, but checks the normal operation of the emergency steering system. There was a problem that could not be done.

An object of the present invention created to solve the above problems, to implement the emergency steering in the emergency of the equipment, to provide a self-diagnostic emergency steering apparatus of the wheel loader that can easily check the normal operation of the emergency steering system. Is in.

An object of the present invention, a steering flow path for supplying the hydraulic oil of the steering pump to the steering cylinder via the first valve and the steering valve, an electric motor driven by a battery and equipped with an emergency steering hydraulic pump on the output shaft, the emergency steering An emergency steering flow passage connecting the hydraulic pump and the priority valve, a first pressure switch detecting the pressure in the steering flow passage, a second pressure switch detecting the pressure in the emergency steering flow passage, the first pressure switch and the first pressure switch. 2 is provided with a pressure value detected from the pressure switch, and when starting, the electric motor is temporarily operated for a predetermined time, and the emergency steering hydraulic pump is broken if the pressure value detected from the second pressure switch is less than a preset value. Outputs an informing signal and if the pressure value of the first pressure switch is less than the set value when starting, Is controlled so as to energize the electric motor and equal to or greater than the preset value can be achieved by the battery and diagnosis of emergency steering apparatus of the wheel loader self comprises a controller which controls to maintain the short-circuited state of said electric motor.

Preferably, in the present invention, the controller further comprises an emergency steering selector switch for releasing or returning a function of notifying whether the emergency steering hydraulic pump has failed when starting up.

Preferably, the means for informing the failure of the emergency steering hydraulic pump at start-up is a starter switch, and if the starter switch is in an off state, the battery and the electric motor are short-circuited and the starter switch is on. ) And a controller provided to short-circuit the battery and the electric motor when the second pressure switch is operated by operating the electric motor and discharged hydraulic oil by energizing the battery and the electric motor.

Preferably, the controller of the present invention is equipped with a safety program to short-circuit the battery and the electric motor when a certain time has passed after the battery and the electric motor is energized.

Preferably, the present invention further comprises a gauge panel connected to receive a signal indicating that the electric motor is running or the emergency steering hydraulic pump is broken from the controller.

More preferably, the present invention further comprises an emergency steering check valve provided at the confluence of the branching flow path and the emergency steering flow path for supplying the hydraulic oil of the steering pump to the priority valve and the steering valve.

Hereinafter, the configuration of the present invention will be described in detail with reference to the drawings.

2 is a circuit diagram showing a self-diagnosis emergency steering apparatus of a wheel loader according to the present invention.

2, an emergency steering hydraulic pump 8, a first pressure switch 16, emergency steering, which is mounted on a steering flow path L1, an electric motor 7, and an electric motor output shaft according to the present invention to discharge hydraulic pressure And a second pressure switch 17 and a controller 30 for detecting the pressure of the discharge hydraulic pressure of the hydraulic pump 8.

When the wheel loader operates normally, the hydraulic oil discharged from the steering pump Ps is supplied to the priority valve 3 and the steering valve 4 through the steering flow path L1, and a steering wheel (not shown) or a joystick (not shown). Are supplied to the corresponding steering cylinders 4a by steering operation, respectively.

However, when the engine of the wheel loader is turned off or is not in a normal operating state, the steering fluid discharged from the steering pump Ps may be less or less than normal, and thus steering may not be realized. In order to solve this disadvantage, the present invention provides an emergency steering means.

The emergency steering means according to the present invention includes a first pressure switch 16 provided in the branch flow path L2 and an electric motor 7 and is controlled by the controller 30.

Here, the electric motor 7 is selectively energized with the battery BAT, and the above-described first pressure switch 16 detects the pressure in the steering flow path L1 or the branch flow path L2 so that the detected value is less than the set value. In case of operation (when emergency steering is required), the battery BAT and the electric motor 7 are energized by the controller 30 so that the hydraulic oil of the flow path L3 is passed through the emergency steering flow path Le. Is supplied to the corresponding steering cylinder 4a via the steering valve 4.

In the present invention, the pressure detecting method of the steering flow path L1 or the branch flow path L2 is a normal open type in which the contact is closed only when the first pressure switch 16 is applied with a pressure higher than a set value. If the contact is closed, the equipment is in normal operating condition. If the contact is open, the engine of the equipment is stopped or abnormally operating. In the present invention, the pressure switch is used, but not limited thereto. Sensors of various types, shapes, or methods may be applied.

The emergency steering means according to the present invention is configured to automatically make emergency steering by means of an emergency steering program mounted on the controller 30 when it is determined that the pressure in the steering flow path L1 is less than a predetermined value. Since the steering state is unknown, a lighting gauge panel GP is provided inside the cab to identify the emergency steering state. Here, the gauge panel GP is electrically connected to the controller 30 and is turned on or flashes depending on whether the first pressure switch 16 is operated.

In addition, the present invention is provided with an emergency steering select switch 20 that can release or restore the function of the controller 30 by the driver's selection.

In addition, the present invention includes a self-diagnostic means capable of diagnosing the emergency steering means, in particular the operation of the electric motor (7).

The self-diagnostic means comprises a starter switch (SS), a second pressure switch (17) for detecting the discharge pressure of the emergency steering hydraulic pump (8), and a controller (30) equipped with a self-diagnosis program.

The self-diagnosis means according to the present invention is fixed when the driver inserts a key of the equipment into the starter switch SS to start the equipment, that is, when the switch is switched to the on position where the switch is applied with electricity. During the period of time, the controller 30 energizes the battery BAT and the electric motor 7 by the on-board self-diagnosis program to transfer the hydraulic oil of the flow path 30 through the emergency steering flow path Le as described above. And the steering cylinder 4a are selectively supplied to the steering cylinder 4a.

Here, the second pressure switch 17 is provided in the flow path in branch communication with the emergency steering flow path (Le), the operation according to the normal operation of the emergency steering hydraulic pump (8) directly connected to the output shaft of the electric motor (7). Or deactivated. Therefore, when the emergency steering hydraulic pump 8 is normally operated, the second pressure switch 17 is operated and the signal is transmitted to the controller 30, and the controller 30 is connected to the battery BAT and the electric motor by the self-diagnosis program. Short-circuit 7).

In addition, the driver can know whether the emergency steering hydraulic pump 8 is normally operated by the lighting of the above-described gauge panel GP. For example, when the second pressure switch 17 is operated by the hydraulic fluid discharged after the emergency steering hydraulic pump 8 is normally operated in the self-diagnosis process, the driver 30 turns on the gauge panel GP by the controller 30. It can be confirmed whether the emergency steering hydraulic pump 8 including the motor 7 operates normally.

The controller 30 according to the present invention is equipped with a safety program to short-circuit the battery BAT and the electric motor 7 after a certain time has elapsed regardless of whether the emergency steering hydraulic pump 8 is operated. This is because the self-diagnosis of the present invention does not require a long time because it is for diagnosing whether the emergency steering device operates normally.

In addition, an emergency steering check valve 15 is provided to prevent a back flow of the working oil to a portion where the branch flow path L2 and the emergency steering flow path Le join.

Referring to the operation relationship of the self-diagnosis emergency steering apparatus of the wheel loader of the present invention having the above configuration as follows.

Close the first pressure switch 16

This state is that the wheel loader is operating normally.

1st pressure switch 16 open

As the engine is stopped or abnormally operated during the operation of the wheel loader, the controller 30 energizes the battery BAT and the electric motor 7 by an emergency steering program to supply hydraulic oil of the oil passage L3 to the emergency steering flow path ( Le) is supplied to the corresponding steering cylinder 4a in response to the operation of the steering wheel (not shown) or the joystick (not shown) via the priority valve 3 and the steering valve 4 to temporarily steer. To be done.

In this case, the gauge panel GP is turned on to identify the driver as an emergency steering state.

Self-diagnosis

When the wheel loader is started, when the key is inserted into the starter switch (SS) to switch to the on position, the controller 30 energizes the battery BAT and the electric motor 7 by a self-diagnosis program for a predetermined time and makes an emergency. The second pressure switch 17 is operated in accordance with the discharge pressure of the steering hydraulic pump 8, and as a result, the normal operation of the emergency steering means is determined according to the controller 30 in accordance with the lighting of the gauge panel GP. You can check it. Detailed description thereof will be omitted since it has been described above.

Then, the controller 30 ends the self-diagnosis by shorting the battery BAT and the electric motor 7 when a set time, for example, 3 to 5 seconds has elapsed by the safety program.

Although the present invention described above is limited to the above-described embodiments, the present invention is not limited thereto, and the present invention may be easily modified by those skilled in the art. It is obvious that it belongs to the technical idea of the.

The present invention having the above configuration can confirm the normal operation of the emergency steering means during the set time automatically at start-up as well as the emergency steering of the equipment has the effect of ensuring safety and reliability.

Claims (3)

A steering flow path L1 for supplying hydraulic oil of the steering pump Ps to the steering cylinder 4a via the priority valve 3 and the steering valve 4; An electric motor 7 driven by a battery BAT and equipped with an emergency steering hydraulic pump 8 on an output shaft; An emergency steering flow path (Le) connecting the emergency steering hydraulic pump (8) and the priority valve (3); A first pressure switch (16) for detecting the pressure in the steering flow path (L1); A second pressure switch (17) for detecting a pressure in the emergency steering flow path (Le); The pressure value detected from the first pressure switch 16 and the second pressure switch 17 is provided, and at start-up, the electric motor 7 is temporarily operated for a predetermined time and the emergency steering hydraulic pump 8 is provided. When the pressure value detected from the second pressure switch 17 by the discharge of less than the predetermined value outputs a signal indicating that the emergency steering hydraulic pump 8 is broken, and when the first pressure switch ( If the pressure value of 16) is lower than the set value, the battery BAT and the electric motor 7 are controlled to be energized. If the pressure value is higher than the set value, the battery BAT and the electric motor 7 are kept short-circuited. Self-diagnosis emergency steering device of the wheel loader comprising a controller (30) for controlling. The method of claim 1, The controller 30 short-circuits the battery BAT and the electric motor 7 when a predetermined time elapses after the battery BAT and the electric motor 7 are energized. Emergency steering system. The method of claim 1, And a gauge panel (GP) connected to receive the signal from the controller (30) indicating that the electric motor (7) is running or the emergency steering hydraulic pump (8) is broken.

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