JP2016113119A - Work machine and electric circuit of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a work machine and an electric circuit of the same, which can prolong a retention time of a battery when an engine stops or an engine speed is reduced below a set value.SOLUTION: A work machine comprises: a battery 11; a key switch 12 having a key-on terminal connected to the battery 11 during key-on; a fuel pump 14 connected to the key-on terminal through a power supply line 28; a charge lamp 24 connected to the key-on terminal through a power supply line 29; a power generator 13 which is connected to an output shaft of an engine and to the charge lamp 24 through an earth line 23, and comprises a regulator 25 for grounding the earth line 23 on condition that the engine stops or an engine speed is reduced below a set value; and a relay 19 for cutting off the power supply line 28 when it is electrified to the charge lamp 24.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a work machine and its electric circuit.

  Some work machines such as hydraulic excavators can be remotely operated with a remote controller or the like (see Patent Document 1).

JP2013-168778A

  Even for a work machine that supports remote control, it is often necessary to operate a key switch in the operator's cab to turn the work machine body on and off. Therefore, even if the engine is stopped due to some trouble during remote operation and the operation becomes impossible, there may be an electric device that continues to operate because the key switch remains on. At sites that are not immediately accessible to the work machine, there is a concern that the battery of the work machine will run up.

  An object of the present invention is to provide a work machine and its electric circuit capable of extending the duration of a battery when the engine stops or falls below a set value and the rotational speed decreases.

  In order to achieve the above object, an electrical circuit of a work machine according to the present invention is connected to a key switch having a battery, a key switch having a key-on terminal connected to the battery at the time of key-on, and the key-on terminal via a first power supply line. Connected to the key-on terminal via a second power supply line, and to an output shaft of the engine and connected to the warning device via a ground line to stop the engine or A generator having a regulator for grounding the earth line under a condition that the rotational speed is lower than a set value, and a relay for cutting off the first power feeding line when the warning device is energized. .

  According to the present invention, it is possible to extend the duration of the battery when the engine stops or falls below a set value and the rotational speed decreases.

1 is a side view of a hydraulic excavator that is an example of a work machine to which an electric circuit according to an embodiment of the present invention is applied. It is the electric circuit diagram which extracted and represented the part which concerns on one Embodiment of this invention among the electric circuits mounted in the hydraulic shovel shown in FIG.

  Embodiments of the present invention will be described below with reference to the drawings.

1. Working Machine FIG. 1 is a side view of a hydraulic excavator that is an example of a working machine to which an electric circuit according to an embodiment of the present invention is applied.

  A hydraulic excavator 1 shown in FIG. 1 includes a traveling body 4 for traveling and traveling, a revolving body 2 that is pivotably mounted on an upper portion of the traveling body 4, and a working device 6 that is provided on the front portion of the revolving body 2 so as to be able to be raised and lowered. It has. The traveling body 4 and the revolving body 2 constitute a vehicle body. The work device 6 is an articulated excavator, and is attached to the front side of a ladder-like base frame 5 that forms a support structure of the revolving structure 2. A cab 9, an engine compartment 10 and a counterweight 3 are also mounted on the base frame 5. The base frame 5, the cab 9, the engine compartment 10, the counterweight 3, and the like supported by the base frame 5 are components of the revolving structure 2. The cab 9 is on the left side of the base of the working device 6, the counterweight 3 is on the opposite side (rear part) of the working device 6 across the turning center of the swing body 2, and the engine compartment 10 is between the counterweight 3 and the cab 9. Is located in each.

2. Electrical Circuit FIG. 2 is an electrical circuit diagram showing an extracted portion of the electrical circuit mounted on the hydraulic excavator 1 according to the present embodiment.

  The electric circuit shown in FIG. 2 includes a battery 11, a key switch 12, a generator 13, a fuel pump 14, an operating device 15, a receiving device 16, a controller 17, a monitor 18, and a relay 19.

  The negative terminal of the battery 11 is grounded, and the positive terminal is connected to each B terminal of the key switch 12 and the generator 13. The battery 11 stores the electric power supplied from the generator 13, and supplies electric power to the electric devices (in FIG. 2, the fuel pump 14, the controller 17, the monitor 18, etc.) via the key switch 12 at the time of discharging.

  In addition to the B terminal, the key switch 12 includes a BR terminal, an R1 terminal, an R2 terminal, a C terminal, and an Acc terminal. When the key switch 12 is in the warm-up position (PRE-HEATING), the B terminal, the BR terminal, and the R1 terminal are connected, the BR terminal and the R1 terminal are connected to the battery 11 through the B terminal, the R2 terminal, the C terminal, and The connection between the Acc terminal and the battery 11 is cut off. When the key switch 12 is set to the key-off position (OFF), the connection between the B terminal and the other terminals is cut off, and the connection between the BR terminal, R1 terminal, R2 terminal, C terminal and Acc terminal and the battery 11 is cut off. When the key switch 12 is set to the key-on position (ON), the B terminal, BR terminal, R2 terminal and Acc terminal are connected, the BR terminal, R2 terminal and Acc terminal are connected to the battery 11 via the B terminal, the R1 terminal and The connection between the C terminal and the battery 11 is cut off. In the specification of the present application, “key-on terminal” means a BR terminal, an R2 terminal, or an Acc terminal connected to the battery 11 at the key-on position. When the key switch 12 is set to the start position (START), the B terminal, BR terminal, R1 terminal, C terminal and Acc terminal are connected, and the BR terminal, R1 terminal, C terminal and Acc terminal are connected to the battery 11 via the B terminal. The connection between the R2 terminal and the battery 11 is interrupted.

  The generator 13 is connected to an output shaft of an engine (not shown) housed in the engine room 10 and is driven by the engine to generate power. The B terminal of the generator 13 is connected to the B terminal of the key switch 12 and the battery 11, and power is supplied to the battery 11 and the key switch 12 through the B terminal during power generation. The IG terminal of the generator 13 is connected to the BR terminal of the key switch 12 through the power supply line 28. The L terminal of the generator 13 is connected to the charge lamp 24 of the monitor 18 via the earth line 23. The charge lamp 24 is connected to the Acc terminal of the key switch 12 through the power supply line 29. Fuses 20 and 21 are provided in the middle of the power supply lines 28 and 29, respectively. For example, the monitor 18 is provided at a position where a passenger who has boarded a driver's seat (not shown) in the driver's cab 9 can easily visually recognize. Yes. The charge lamp 24 is a warning device that informs the passenger that the engine and the generator 13 are stopped or the number of revolutions thereof is below a predetermined set value (lower limit value) and the battery 11 is in a discharged state. In the present specification, a state where the engine is stopped or a state where the engine speed is lower than a set value is referred to as engine stop or the like. The generator 13 is provided with a regulator 25 for grounding the ground line 23 on condition that the engine is stopped.

  The operation device 15 is provided adjacent to a driver's seat (not shown) in the cab 9 and outputs an operation signal corresponding to the operation direction and the operation amount to the controller 17. The receiving device 16 receives an operation signal from a remote operation device 22 such as a remote controller, and outputs the received operation signal to the controller 17. The controller 17 calculates a command value according to the input operation signal, and outputs a command signal to a corresponding control target device (not shown). Examples of the control target device include a control valve that controls the flow of pressure oil supplied to the hydraulic actuators that drive the work device 6, the traveling body 4, and the revolving body 2, respectively.

  The fuel pump 14 serves to supply fuel to the engine, and is connected to the BR terminal of the key switch 12 via the fuse 20. A relay 19 is provided in the middle of the wiring connecting the fuel pump 14 and the BR terminal of the key switch 12. The relay 19 includes a coil 26 and a switch 27. The coil 26 connects the power supply line 28 and the earth line 23. The switch 27 is provided on the power supply line 28 and communicates or blocks the power supply line 28.

3. Operation When the key switch 12 is set to the start position (START), a starter motor (not shown) is provided on the condition that a lock lever (not shown) as a safety device that prohibits the operation by the operating device 15 is in the locked state (operation prohibited state). The engine rotates (not shown) and the engine (not shown) starts. When the engine starts, the generator 13 rotates, the voltage at the B terminal of the generator 13 rises, the battery 11 is charged, and the voltage is applied to the B terminal of the key switch 12 by the generator 13. Thereafter, the engine and the generator 13 continue to operate even after the key switch 12 is in the key-on position (ON).

  In the key-on position, the B terminal is connected to the BR, R2 and Acc terminals inside the key switch 12. As a result, a voltage is applied to the fuel pump 14 connected to the BR terminal. Since the fuel pump 14 is grounded, a current flows through the fuel pump 14 via the BR terminal, the power supply line 28, the fuse 20 and the switch 27 of the relay 19, and the fuel pump 14 is driven. Further, a current also flows to the IG terminal of the generator 13 via the BR terminal, the power supply line 28 and the fuse 20, and this becomes a power source for the regulator 25. On the other hand, a current also flows through the Acc terminal, the power supply line 29 and the fuse 21 to the controller 17 connected to the Acc terminal, and this becomes the power source of the controller 17. However, although a voltage is also applied to the charge lamp 24 connected to the Acc terminal, no current flows through the charge lamp 24 and the charge lamp 24 is turned off because the L terminal of the generator 13 is not grounded by the regulator 25 during engine rotation. It is in the state.

  In the present specification, a state in which the key switch 12 is in the key-on position and the engine is operating normally is referred to as a movable state, and when the operation device 15 or the remote operation device 22 is operated in the movable state, A command signal is output from the controller 17 and the excavator 1 operates.

  At this time, if the engine is stopped due to some trouble in the movable state, the L terminal of the generator 13 is grounded by the regulator 25 provided in the generator 13. As a result, the earth line 23 is grounded, a current flows through the charge lamp 24, and the charge lamp 24 is turned on. At the same time, the power supply line 28 is also grounded via the relay 19 and the ground line 23, and in the relay 19, the current flowing through the power supply line 28 flows to the coil 26, so that the coil 26 is excited and the switch 27 is opened. The current supplied to the fuel pump 14 is cut off. As a result, the fuel pump 14 stops.

4). 2. If the relay 19 is omitted in the electric circuit of FIG. 2 and the power supply line 28 is connected to the fuel pump 14 without the relay 19, the engine 13 is stopped due to some trouble, the B terminal of the generator 13 The voltage is lowered, and the battery 11 is switched to a discharged state. At this time, since the connection state between the BR terminal of the key switch 12 and the fuel pump 14 is maintained, the fuel pump 14 is driven even though the generator 13 is not operated, and the power of the battery 11 is wasted. End up.

  On the other hand, in this embodiment, paying attention to the charge lamp 24 that lights when the engine is stopped or the like, a relay 19 is provided in the power supply line 28, and when a current flows through the wiring of the charge lamp 24, the power supply line is switched by the switch 27. 28 was cut off. Thereby, even if the battery 11 is switched to a discharged state when the engine is stopped or the like, the power supply to the fuel pump 14 is cut off, so that the power consumption of the battery 11 can be suppressed. Therefore, the duration of the battery 11 when the engine is stopped can be greatly extended.

  In particular, in the case of the hydraulic excavator 1 that supports remote operation as in this embodiment, when operating in a high radiation environment where humans cannot enter by remote operation, even if the engine is stopped due to a communication error or the like, the rescue robot The possibility of sustaining the battery 11 is greatly increased until it arrives. Therefore, even when the hydraulic excavator 1 is operated where a person cannot easily approach, the possibility that the hydraulic excavator 1 can be returned to the movable state by restarting the engine increases when the engine is stopped.

5. Others In the present embodiment, the case where the fuel pump 14 is selected as the power supply cutoff target when the engine is stopped due to the large amount of power consumption has been described as an example. Not exclusively. If the electrical device is connected to the battery 11 via the key-on terminal, the power supply is cut off when the engine is stopped or the like, thereby contributing to the suppression of power consumption of the battery 11. Therefore, for example, providing the relay 19 in a circuit for operating a work light and an air conditioner (air blowing) also leads to the extension of the duration of the battery 11. In addition, the charge lamp 24 is described as an example of a warning device that is a driving target of the ground line 23 through which the driving current of the relay 19 flows. However, the warning device connected to the ground line 23 is not a simple indicator lamp, for example, It is also possible to apply an apparatus (buzzer, speaker, LCD, etc.) having a warning sound, voice, and other display functions. In addition, the current flows through the coil 26 from the ground line 23. In short, since the current flowing through the charge lamp 24 only needs to flow through the coil 26, the coil 26 is connected to the power supply line 29 instead of the ground line 23. A configuration is also conceivable.

  In addition, although an example of application to a work machine that supports remote operation has been described, even if the present invention is applied to a work machine that does not support remote operation, power is supplied to a specific electrical device when the engine is stopped, etc. By cutting off the battery, the effect of extending the battery duration can be obtained. Further, the present invention is applied to the hydraulic excavator 1 that operates by driving a control valve (not shown) by an electrical command signal output from the controller 17 in response to an operation signal from the operation device 15 or the receiving device 16. Although illustrated, for example, the present invention can also be applied to a work machine that operates by driving a control valve with a hydraulic signal (pilot pressure) from the operation device 15. Furthermore, the case where the present invention is applied to the hydraulic excavator 1 having one working device 6 has been described as an example, but a so-called double-arm type working machine having two working devices, a wheel loader, or the like The present invention can be applied to other types of work machines, and the same effects can be achieved. The size (machine mass) of the work machine to be applied is not limited.

1 Excavator (work machine)
2 Revolving body (car body)
4 Running body (car body)
6 Working device 11 Battery 12 Key switch 13 Generator 14 Fuel pump (electrical equipment)
16 Receiver 17 Controller 19 Relay 23 Ground Line 24 Charge Lamp (Warning Device)
25 Regulator 28 Feeding line (first feeding line)
29 Feeding line (second feeding line)
Acc, BR, R1, R2 terminals (key-on terminals)

Claims (4)

Battery,
A key switch having a key-on terminal connected to the battery at the time of key-on;
An electrical device connected to the key-on terminal via a first power supply line;
A warning device connected to the key-on terminal via a second power supply line;
A generator connected to the output shaft of the engine and connected to the warning device via a ground line, and having a regulator that grounds the ground line on condition that the engine is stopped or the rotational speed is lower than a set value;
An electrical circuit for a working machine, comprising: a relay that shuts off the first power supply line when the warning device is energized.   2. The electric circuit for a working machine according to claim 1, wherein the electric device is a fuel pump. In the electric circuit of the working machine according to claim 1,
A receiving device for receiving an operation signal from the remote control device;
An electrical circuit for a work machine, comprising: a controller that controls the work machine according to an operation signal received by the receiving device. The car body,
A working device provided on the vehicle body;
A battery mounted on the vehicle body;
A key switch having a key-on terminal connected to the battery at the time of key-on;
An electrical device connected to the key-on terminal via a first power supply line;
A warning device connected to the key-on terminal via a second power supply line;
A generator connected to the output shaft of the engine and connected to the warning device via a ground line, and having a regulator that grounds the ground line on condition that the engine is stopped or the rotational speed is lower than a set value;
A work machine comprising: a relay that cuts off the first power supply line when the warning device is energized.

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