KR20020019404A - Controller for work vehicle - Google Patents

Abstract

PURPOSE: To provide a control device for a working vehicle easily resolving the cause by allowing input of power supply for many times in occurring of overcurrent abnormality in an electric circuit. CONSTITUTION: In this control device for the working vehicle controlling the working machine 3 and drive actuators 49, 46, and 45 for the traveling and having the electric circuit with a protective appliance for the overcurrent, the protective appliance is provided with circuit breakers 11-19 and the circuit breakers 11-19 are concentrated in a prescribed part or a car body.

Description

CONTROLLER FOR WORK VEHICLE}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control apparatus for a work vehicle capable of improving maintenance management, such as failure diagnosis when a failure occurs due to an overcurrent caused by a short circuit of a circuit load.

Background Art In recent years, in order to realize high performance, high functionality, high maintenance, and the like, a control apparatus for controlling an actuator based on an electric signal is often used. These control devices are mainly composed of a computer, perform a predetermined calculation process based on detection signals of various sensors, and output a control command in accordance with the calculation result, drive control of each work machine, vehicle driving, and the like. And a variety of electric or hydraulic actuators, and a driving device for driving the various actuators in response to the control command. In general, in order to protect an excessive current from flowing through a controller, each drive device, each actuator, and a wiring when a failure of various sensors or actuators, a short circuit or a ground fault, etc. occur in these devices, It is equipped with overcurrent protection function and protection device such as current limiting circuit or fuse.

In the case of construction machinery, as a fuse, a normal one that melts and cuts off when an excessive current flows and protects the circuit is installed in a predetermined position so as to be replaceable.

If a part of the circuit load breaks down and an overcurrent flows, the fuse of the circuit melts and is cut off to protect the circuit. In this case, after the field engineer (so-called serviceman) finds the cause of the failure, the control device can be used again in exchange for a replacement new fuse.

However, in the conventional method of circuit protection by the fuse, the following problem arises.

If the fuse is melted and shut off, it is a normal procedure for the field engineer to find out the cause of the failure and replace it with a new one. However, in recent years, many loads (actuator drive circuits and sensors, etc.) are connected to one controller in order to realize high functions, high performance, and high maintenance control. The load path is complex and diverged in multiples. Therefore, it is difficult to immediately identify the cause of the failure in a short time. On the contrary, in order to find the cause of the failure, it is often necessary to replace the fuse temporarily, turn on the power of the control device, and grasp the failure situation. The fuse will melt and block. As a result, a large number of spare fuses are required, maintenance costs increase, and when there is no spare fuse at the time of troubleshooting, it is very difficult to find a fixed cause.

In particular, in case of a vehicle failure in a place where the distance from the service center where the field engineer is located, such as in a deep mountain crushing ground, for example, it takes time for the field engineer to travel between the site and the service center. As much as possible, it is required to complete the troubleshooting by only one work in the field. For this reason, it is necessary to understand the failure situation in detail, to estimate the cause of the failure, to leave the site fully equipped with repair parts, etc., and to contact the workers in the field to receive the symptoms of the vehicle when the power is turned on several times. It may be necessary. At this time, since there are many cases in which the fuse is hardly provided by re-powering on, the failure situation cannot be understood in detail, and as a result, the number of round trips between field engineers increases or the time taken for troubleshooting is increased. there is a problem.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and it is to provide a control device for a work vehicle that enables re-powering of the power supply so that the cause can be easily identified when an overcurrent abnormality occurs in the electrical circuit of the control device. It is aimed.

1 is a side view of a hydraulic excavator to which the present invention is applied.

2 is a perspective view of a mounting portion of a CB box and a battery according to the present invention.

3 is a circuit block diagram of a control device for holding an electric circuit using the CB of the present invention.

4 is a side view showing another embodiment of the installation position of the CB box.

5 is a plan view of FIG. 4.

6 is an explanatory diagram of a CB box.

(Explanation of symbols for the main parts of the drawing)

2 … Upper pivot 2a... Turning frame

3…. Working machine 4. Cab

5, 6... Step cover 7. battery

8 … Step plate 8a... step

10... CB boxes 11 to 19. CB

20... Fuse box 31. Start switch

32. Battery relay 33. Wiper motor

34. Working tools 35. headlight

36. Electric feed pump 37. Pump controller

38. Engine controller 39. Monitor device

41…. Traveling solenoid valve 42. Swing solenoid valve

43. Cut-off cancellation solenoid valve 44. Torque Control Solenoid Valve

45.. Driving motor 46. Turning motor

47. Variable displacement hydraulic pump 48. Selector valve

49. Hydraulic cylinder for working machine 51. sensor

52... Interlock switch 61. Injector

62. Supply pump

In order to achieve the above object, the first invention of the control device for a work vehicle according to the present invention is to provide a working vehicle including an electric circuit that controls a drive actuator such as a work machine and a run, and provides a protection device against overcurrent. In the control apparatus, the protection device has a circuit breaker, and the protection device has a configuration in which the protection circuit breaker is concentrated at a predetermined position of the vehicle body.

According to the first invention, even if the circuit breaker is turned off (trip) due to the overcurrent of the load, the power supply can be immediately turned on again several times, so that the failure situation can be easily understood and the diagnosis can be facilitated. . If only one function is not used, for example, if only one actuator is not driven, the circuit breaker may not trip, and the vehicle may move and move. In this case, the circuit breaker immediately turns on the power to provide service. It can be moved to a place close to the center, making repairs easier. In addition, since the circuit breaker is provided concentrated at a predetermined position, the circuit breaker is easy to operate and maintainability is very good.

According to a second invention, the circuit breaker is provided in the vicinity of a battery for power supply based on the first invention.

According to the second invention, the distance between the circuit breaker and the battery for the power supply is shortened, and the circuit portion protected by the circuit breaker can be increased. Thus, the reliability and maintenance of the electric circuit can be improved.

According to a third aspect of the present invention, in the first invention, the electric circuit provided with the circuit breaker is a power supply circuit to a controller such as a monitor device, an engine controller, and a pump controller.

According to the third aspect of the present invention, when a circuit breaker of a controller device in which a large number of current loads are connected such as a monitor device, an engine controller, a pump controller, and the like is tripped, how many times is necessary to investigate which of the plurality of current loads causes a short circuit? The power supply can be turned back on to identify the fault condition. Therefore, troubleshooting of these devices can be made very easy. It is economical since it is completed even if it does not have many spare fuses conventionally.

EMBODIMENT OF THE INVENTION Below, embodiment of this invention is described in detail with reference to drawings. In addition, in the following embodiment, a hydraulic excavator is demonstrated as an example to a working vehicle.

1 is a side view of a hydraulic excavator to which the present invention is applied. The hydraulic excavator shown in FIG. 1 is provided with the lower traveling body 1 drive-driven by the traveling motor controlled by receiving the hydraulic oil from the hydraulic pump which rotates by the power of the engine which is not shown in figure. The upper traveling body 2 is rotatably mounted in a substantially central portion of the lower traveling body 1, and is pivotally driven by a turning motor (not shown). In addition, a work machine 3 such as a boom, an arm, and a bucket is provided so as to be able to swing up and down at approximately the center of the front part of the swing frame 2a of the upper swing body 2, and a hydraulic cylinder (boom cylinder 3a for each work machine) is provided. Etc.). The cab 4 is attached to the front left end of the swing frame 2a, and a battery 7 is provided at the front of the right side of the swing frame 2a. The 1st step cover 5 is provided so that opening and closing is possible above the battery 7, and has covered the upper part of the battery 7. As shown in FIG. The first step cover 5 may be opened and closed by rotationally moving in the front-rear direction or the left-right direction. In addition, the second step cover 6 is disposed to be inclined rearward and upward from the rear of the first step cover 5, and the circuit breaker is provided on the inner frame 9 covered by the second step cover 6. A box (hereinafter referred to as a CB box) 10 is provided. In the CB box 10, as described in detail later, a predetermined number of circuit breakers (hereinafter, referred to as CBs) for overcurrent protection of the power supply circuit of the control device are provided. The handrail 5b is provided in the side edge part of the upper surface of the step cover 5 and 6. As shown in FIG.

2 is a perspective view of the mounting portion of the CB box 10 and the battery 7. As shown in FIG. 2, the scaffolding plate 5a is fixed to the upper surface portion (above the battery 7) of the first step cover 5. In addition, a hole 6a is formed in the second step cover 6 in front of the CB box 10, and the step plate 8 has a second step cover 6 so as to cover the hole 6a. It is installed to open and close. The step plate 8 is formed with a recess in which the step 8a is provided.

3 is a circuit block diagram of a control device for holding an electric circuit using CB according to the present invention. In the following description, since it is easy to understand by the simplification of the description, it will be described functionally (functionally) with a focus on the connection of the power supply circuit.

In the figure, the output voltage of the battery 7 is input to the B terminal of the start switch 31 via the CB 11 in the CB box 10, and from the BR terminal when the start switch 31 is turned on. It is applied to the excitation coil 32c of the battery relay 32. The excitation current of the battery relay 32 returns to the negative voltage terminal (normally car chairs) of the battery 7. When the battery relay 32 is turned on, the power supply current from the battery 7 is transferred from the output (a) contact 32a (standard open) of the battery relay 32 to each CB (12, 13) in the CB box 10. , Wiper motor 33 (for window of cab 4), work lamp 34 (illuminates front of work machine 3) via head 14, 15, 16, 17, headlight 35, respectively. (Light in front of the body), electric feed pump 36, pump controller 37 (to control the hydraulic pump for the hydraulic actuator for driving the work machine 3 and the vehicle running), and the predetermined in the fuse box 20 Is supplied to the fuses 21, 22, 23, and the like.

From these fuses 21, 22, 23 and the like, power is supplied to an air conditioner, a heater, a horn 68, a radio, a window washer motor and the like, respectively.

In addition, the output voltage of the battery 7 is directly via the CBs 18, 19, and 17a in the CB box 10, respectively, to the engine controller 38 (controlling the engine speed efficiently and with high precision), It is applied to the monitor device 39 (having the function of the machine interface), predetermined fuses 25 and 26 in the fuse box 20, etc., and room light or steplight (step) from the fuses 25 and 26 or the like. Power is supplied to the covers 5 and 6).

As a current load of the pump controller 37, the traveling solenoid valve 41 and the pre-rotator valve 42 which perform drive control of the traveling motor 45 and the turning motor 46, respectively, the traveling motor 45, and the turning motor The output torque of the variable displacement hydraulic pump 47 for supplying the pressurized oil through the control valve 48 which can be controlled to the 46 and the hydraulic cylinder 49 for the work machine (the cylinder 3a for the boom, etc.) can be efficiently and accurately A cutoff cancel solenoid valve 43 and a torque control solenoid valve 44 for controlling the road are connected, and each of these solenoid valves 41, 42, 43, 44 is controlled from the pump controller 37. It is controlled by the command current. The pump controller 37 further includes a detection signal from sensors 51 such as various pressure sensors and pressure switches, a switch signal from the actuator control interlock switch 52, and a clogging sensor 64 of the air cleaner of the engine. Detection signals and the like are respectively input.

As the current load of the engine controller 38 (which controls the rotation speed of the engine efficiently and with high accuracy), the injector 61 (fuel injection valve of the engine), the supply pump 62 (to feed fuel), Sensors 63 such as engine speed, various pressures, oil temperature and water temperature are connected. The injector 61 and the supply pump 62 are controlled by the control command current from the engine controller 38.

The start switch 65 is supplied with a power supply current directly from the C terminal of the start switch 31 when the start switch 31 is turned on.

As the current load of the monitor device 39, the wiper motor 33, the horn 68, and the buzzer 67 (used for running alarm alarm, work machine alarm alarm, etc.) and the like are connected. It operates by the control command current from (39).

In each of the CBs 11 to 17a, 19, the breaking characteristics between the current value (rated current value) and the operation time at the time of trip are set in accordance with the maximum load current in the corresponding circuit. Moreover, these CBs have a trip switch of the type which returns when an overcurrent flows and trips (that is, it protrudes outward from a CB main body). After the trip, the power can be turned on again by pressing the trip switch. Moreover, these CBs are suitable for use environment conditions such as vibration, shock and ambient temperature when the work vehicle is operated. Moreover, since the trip switch at the time of return is employ | adopted, it can be miniaturized and it is suitable at the time of vehicle loading.

According to the above configuration, the power supply circuits of the controllers, the drive units, and the electric equipments of the control device are protected by the overcurrent by the CB. Even if an overcurrent occurs due to any one short circuit failure, In addition to protection, it is also possible to immediately turn the power back on for troubleshooting. At this time, it is not necessary to prepare a plurality of preliminary fuses as described in the prior art items, and since the power can be turned on several times, it is possible to easily diagnose the failure and learn economically. In particular, in order to improve the control function and to increase the precision, circuits according to controllers such as the pump controller 37, the engine controller 38, and the monitor device 39, in which a large number of current loads such as actuators and sensors are connected to each other, are used. Even when an overcurrent abnormality occurs, it is possible to immediately investigate the fixed state after turning on the corresponding CB and turning the power on again, while sequentially removing the current load connected to the controller. It can be done.

In addition, since the CB box 10 is placed near the power supply battery 7 to shorten the wiring distance between the CB box 10 and the battery 7, the circuit part which can be protected by the CB (equipment or wiring). ) Can be extended, and the reliability is increased. In addition, since the CB box 10 is installed at a location where the CB box 10 can be easily opened and closed from the outside and the CB can be easily operated, workability during repair is good.

Further, for example, a short circuit occurs between the motor coil and the case inside the electric feed pump 36, and the electric feed pump 36 is operated so that a short circuit current flows only when the electric motor inside is at a predetermined rotational position. If this occurs, it is also possible to turn on the CB 15 again, turn the power on again, and move the work vehicle to a predetermined service point without the electric feed pump 36 operating. As a result, trouble shooting can be performed more easily.

The position at which the CB box 10 is to be installed is not limited to the above position, and may be a place where other workers can easily contact. For example, FIGS. 4 to 6 show an embodiment in which the CB box 10 is installed, and a space is provided between the cab 4 and the hydraulic oil tank 71 provided at the rear of the cab 4. The CB box 10 may be provided in this space. In the CB box 10, it is arrange | positioned so that the operation which presses the said trip switch after each CB trips is easy, and is located in front of the CB box 10 of this operation direction (namely, the CB box 10 of FIG. 5). The maintenance cover 72 which can be opened and closed is provided in the vehicle side.

By providing the CB box 10 immediately behind the cab 4 in this way, the worker's contact from the cab 4 becomes very good, and thus workability at the time of failure diagnosis is good.

In addition, CB may be applied only to any equipment which is difficult to identify the cause when performing the fault diagnosis and needs to be re-powered a plurality of times, and a fuse other than this may be applied. In addition, CB is not limited to having a return type trip switch, and a yaw may be a circuit breaker.

According to the present invention, since the CB is provided in the power supply circuit of the work vehicle, when a short circuit failure occurs, the power supply can be turned on as many times as necessary and the failure symptom can be immediately recognized. In addition, it is possible to accurately find the cause of the failure in a short time and improve the maintenance management.

Claims (3)

In the control apparatus for a work vehicle provided with an electric circuit which controls the work machine 3 and drive actuators 49, 46, 45, such as traveling, and installs a protection device against overcurrent, the protection device is a circuit breaker ( 11 to 19), wherein the circuit breakers (11 to 19) are concentrated and provided at predetermined positions of the vehicle body. The control device for a work vehicle according to claim 1, wherein the circuit breakers (11 to 19) are provided near a power battery (7). 2. The electric circuit provided with the circuit breakers 11 to 19 is a power supply circuit to a controller such as a monitor device 39, an engine controller 38, a pump controller 37, and the like. Control device of a working vehicle.