JP5096012B2 - Electric drive work vehicle - Google Patents

Description

  The present invention relates to an electrically driven work vehicle in which a working device is provided on a travelable vehicle body, and the working device receives a hydraulic oil supply from a hydraulic unit driven by an electric motor.

  In general, an engine is the main drive source for construction machines, but recently, an electrically driven work vehicle using an electric motor as a drive source has been proposed in consideration of the surrounding environment (for example, Patent Document 1). ). Such a construction machine is equipped with a battery for supplying electric power to the electric motor, and is provided with a control device that controls the operation of various electric components such as the electric motor. In such an electrically driven work vehicle, the workable time is determined according to the chargeable capacity of the battery. Therefore, a battery having a capacity capable of working for one day is mounted, and the day after the work is completed on the next day. Generally, a configuration in which the battery is charged before the start of the operation is employed.

JP 2004-225355 A

  However, since the power consumption of the battery varies greatly depending on the use status of the work device, the frequency, and the work content of the work vehicle, the remaining battery power is lost during the work, and the work cannot be performed. There is also a risk that traveling movement will be impossible. In order to avoid such a situation, the battery capacity may be increased. However, if the battery capacity is increased, the battery mounted on the vehicle becomes larger and heavier, and the work vehicle becomes larger and heavier. For this reason, a battery with a larger capacity is required, and a vicious circle may be repeated.

  In view of such a problem, the present invention can ensure a certain amount of work or traveling movement even in the case where the remaining amount of the battery is exhausted in an electrically driven work vehicle that drives a work device or the like with electric power from the battery. An object of the present invention is to provide an electrically driven work vehicle having such a configuration.

In order to achieve the above object, an electrically driven work vehicle according to the present invention includes a vehicle body having a traveling device that can travel, a working device provided on the vehicle body, a hydraulic unit that drives the working device, An electric motor for driving the hydraulic unit and a main battery for driving the electric motor by supplying driving electric power to the electric motor . On top of that, has a rated voltage of the high voltage from the main battery, a sub battery can be charged to the main battery, and a connection switching means for selectively connecting the sub-battery to the electric motor and the main battery a, wherein the connection switching means, wherein the electric motor can be driven der Rutotomoni by electric power supply to the sub-battery from the sub battery is connected to the electric motor, and the sub-battery is connected to the main battery The main battery is configured to be rechargeable by supplying power from the sub battery.

  The electrically driven work vehicle further includes power generation means provided on the vehicle body, and sub-battery charge control means for charging the sub-battery by supplying generated power supplied from the power generation means to the sub-battery. Is preferred.

In this case, the power generation means is driven by solar power generation means for receiving solar energy to generate power, energy regeneration means for regenerative power generation of driven energy received by the traveling device, or hydraulic oil supplied from the hydraulic unit. The hydraulic oil power generation means for generating power can be configured. Further, when the vehicle body is of a configuration having a pivoting member provided pivotally to the running device may be configured the power generating means from the energy recovery unit for regeneration of the driving energy which the swing body is subjected.

In this configuration, the sub-battery charging control means, when the sub battery is fully charged state, the generated power supplied from said power generating means so as to charge the main battery is supplied to said main battery It is preferable to configure.

  Note that the electrically driven work vehicle according to the present invention is not limited to the configuration of only the electrically driven system, and may be a hybrid drive system that also includes an engine that drives the traveling device and the hydraulic unit.

  In the electrically driven work vehicle according to the present invention configured as described above, in addition to the main battery that drives the electric motor, the sub battery that has a rated voltage higher than the main battery and can charge the main battery Therefore, when the remaining capacity of the main battery is exhausted, the sub-battery is connected to the electric motor by the connection switching means, and the electric motor is driven to perform a certain amount of work or traveling. For this reason, when the remaining capacity of the main battery is exhausted, the work vehicle can be driven to the place where the charging facility is located using the power of the sub battery, and it is sufficient to charge the main battery using this charging facility. Is possible.

  In addition, the power generation means such as photovoltaic power generation, regenerative power generation of driven energy, power generation means driven by hydraulic oil supplied from the hydraulic unit, etc. is provided, and the sub-battery is generated by this power generation means. Thus, the sub-battery can be charged by the power generation means during work and traveling, and the capacity of the sub-battery can always be kept high.

  In this case, when the sub-battery is charged with the generated power from the power generation means and is fully charged, it is preferable to supply the generated power from the power generation means to the main battery to charge the main battery. Thus, while maintaining the sub-battery in a fully charged state, the charging capacity of the main battery can be increased using surplus generated power, and a work vehicle with high energy utilization efficiency can be obtained.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a crawler-type power shovel 1 as an example of an electrically driven work vehicle according to the present invention. The power shovel vehicle 1 includes a travel device 2 configured by providing travel mechanisms 3 and 3 on the left and right of a substantially H-shaped travel cart 4 (vehicle body) in a plan view, and a rear portion of the travel cart 4 that can swing up and down. Blade (discarding plate) 9 provided on the upper side of the traveling carriage 4, a revolving body 11 (vehicle body) provided so as to be turnable, and a shovel mechanism 12 (working device) provided on the front part of the revolving body 11. And an operator cabin 15 (vehicle body) for boarding the driver standing on the upper part of the revolving structure 11.

  A pair of left and right traveling mechanisms 3, 3 constituting the traveling device 2 are provided between a driving sprocket wheel 5 provided at the left and right front part of the traveling carriage 4 and an idler wheel 6 provided at the left and right rear part of the traveling carriage 4. It is constructed by crawling around the crawler belt 7. The driving sprocket wheel 5 is rotationally driven by a traveling motor made up of an electric motor or a hydraulic motor.

  The blade 9 is swung by a blade cylinder 9a made of a hydraulic cylinder. The turning body 11 is turned by a turning motor composed of an electric motor or a hydraulic motor. The shovel mechanism 12 includes a boom 21 pivotably connected to the front portion of the swing body 11, and an arm 22 pivotally connected to the tip of the boom 21 so as to swing up and down within the undulating surface of the boom 21. And a bucket 23 pivotally connected to the tip of the arm 22 so as to be swingable up and down. The boom 21 is raised and lowered by a boom cylinder 24 made of a hydraulic cylinder. The bucket 23 is swung by a bucket cylinder 26 formed of a hydraulic cylinder. In this specification, these hydraulic cylinders and hydraulic motors are collectively referred to as hydraulic actuators.

  The operator cabin 15 is formed in a rectangular box shape that is surrounded by the top, bottom, front, rear, left and right, and performs an operation operation of the operator seat 16 for the driver to sit inside, the traveling device 2 and the excavator mechanism 12. And an operating device 17 are provided. Further, a known solar panel 27 for converting solar energy into electric energy (that is, generating electric power by receiving solar energy) is attached to the ceiling outer surface 15 a of the operator cabin 15. The solar panel 27 is formed in an outer flat plate shape.

  In the power shovel 1, a pump for supplying hydraulic oil to a hydraulic actuator is driven by an electric motor. The hydraulic unit 30 that supplies hydraulic oil to the hydraulic actuator and the power supply system 40 that supplies electric power to the pump electric motor 33 will be described below with reference to FIG. The hydraulic unit 30 and the power supply system 40 are disposed on the revolving structure 11 so as to be covered with the cover member 50. In the configuration shown in FIG. 2, the travel motor and the turning motor are hydraulic motors, and these hydraulic motors are included in the hydraulic actuator.

  The hydraulic unit 30 includes a tank 31 that stores hydraulic oil, a hydraulic pump 32 that is driven by the electric motor 33 for pumps to discharge hydraulic oil at a predetermined hydraulic pressure and flow rate, and hydraulic oil that is discharged from the hydraulic pump 32. A control valve 34 that performs control to supply each hydraulic actuator with a supply direction and supply amount according to the operation, and hydraulic oil power generation that generates power by being rotationally driven in response to the flow of hydraulic oil returning from the control valve 34 to the tank 31 It is comprised from the machine 35. The hydraulic oil generator 35 includes, for example, a rotating blade disposed in a return oil passage from the control valve 34 to the tank 31 and a generator that is rotated by receiving the rotational force of the rotating blade.

  Specifically, as shown in the figure, the control valve 34 controls supply of hydraulic pressure to the blade cylinder 9a, the boom cylinder 24, the arm cylinder 25, the bucket cylinder 26, the travel hydraulic motor 36, and the swing hydraulic motor 38. Here, the traveling hydraulic motor 36 is provided with a regenerative generator 37 that is rotated when the traveling hydraulic motor 36 decelerates to travel to regenerate deceleration energy and generate electric power. Similarly, the swing hydraulic motor 38 is provided with a regenerative generator 39 that generates power by regenerating energy that is rotationally driven during the swing deceleration operation and decelerates the swing.

  The power supply system 40 includes a main battery 41 composed of a secondary battery such as a lithium ion battery or an organic radical battery, and an outlet 42a connected to a commercial power source. The outlet 42a is connected to the commercial power source and AC power from here is supplied. A main charger 42 that receives and charges the main battery 41; an output control device 43 that converts DC power from the main battery 41 into AC power of an arbitrary frequency and supplies the AC power to the pump electric motor 33; A sub-battery 44 composed of a secondary battery such as a lithium ion battery or an organic radical battery, a connection switch 45 for selectively connecting the sub-battery 44 to the main battery 41 and the output control device 43, and the solar panel 27 described above. The sub-battery 4 receives the generated power supply from the hydraulic oil generator 35 and the regenerative generators 37 and 39. Composed of sub charger 46 for charging the. In FIG. 2, the hydraulic oil generator 35 and the regenerative generators 37 and 39 are shown in two places for easy understanding, but in actuality, they are the same.

  As can be seen from the above configuration and FIG. 2, the main battery 41 functions as a power source for the pump electric motor 33 and is set to a high rated voltage and a high capacity (for example, a rated voltage of DC 336 V and a capacity of 30 Kw). The sub-battery 44 is set to a rated voltage (for example, rated voltage DC 400 to 450 V) higher than the rated voltage of the main battery 41 so that the main battery 41 can be charged when connected to the main battery 41 by the connection switch 45. Although set, it is set to a low capacity (for example, 500 W) for the purpose of use to be described later. Therefore, the sub battery 44 is smaller and lighter than the main battery 41.

  The pump electric motor 33 is composed of an AC motor such as an IPM motor (permanent magnet synchronous motor). Therefore, by applying AC power of an arbitrary frequency converted by the output control device 43 to the pump electric motor 33, the output torque of the pump electric motor 33 is controlled to supply a predetermined hydraulic pressure from the hydraulic pump 32. be able to. The power supply at this time is normally performed by the main battery 41, but the electric motor 33 is driven by the power supply from the sub battery 44 by connecting the sub battery 44 to the output control device 43 by the switch 45. You can also.

  The main charger 42 can be connected to a commercial power source via an outlet 42a, and can convert AC power (for example, AC 200V) supplied from the commercial power source into DC power and charge the main battery 41 with an output voltage (DC voltage). In this way, the charging control unit is configured to be controlled. The sub-charger 46 performs control for charging the sub-battery 44 with the electric power supplied from the solar panel 27, the hydraulic oil generator 35 and the regenerative generators 37 and 39. The battery is continuously charged during operation.

  Therefore, as will be described later, when the sub-battery 44 is fully charged, the sub-charger 46 that monitors the sub-battery 44 uses the power supplied from the solar panel 27, the hydraulic oil generator 35, and the regenerative generators 37 and 39. The main battery 41 is supplied and charged.

  The operation of the power shovel 1 configured as described above will be described below. The power shovel 1 is operated by an operator sitting on an operator seat 16 in an operator cabin 15 by operating an operating device 17. Specifically, two operating devices 17 provided upright from the floor in front of the central portion constitute a traveling operation lever for operating the traveling mechanisms 3 and 3, and are provided on the left and right sides of the seat of the operator seat 16. A pair of left and right operating devices 17 provided constitutes a work operating lever for operating the shovel mechanism 12.

  Therefore, when the travel operation lever 17 is operated, the operation of the control valve 34 is controlled based on the operation signal, the hydraulic pressure supply control to the travel hydraulic motor 36 is performed, and the left and right travel mechanisms 3 and 3 are driven. Thus, the control for causing the power shovel vehicle 1 to travel is performed. In addition, in the case where the control for traveling the power shovel vehicle 1 is performed in this way, when the vehicle is decelerated, energy regeneration is performed by the regenerative generator 37 to generate deceleration torque. In this way, the electric power generated by the regenerative generator 37 is supplied to the sub-battery 44 via the sub-charger 46 to charge it. At this time, the power control is performed from the main battery 41 to the pump drive motor 33 by the output control device 43 according to the operation, and the hydraulic pump 32 is driven by the motor 33 so that the hydraulic pressure is supplied to the control valve 34. Have been supplied.

  On the other hand, when the work operation lever 17 is operated, the operation of the control valve 34 is controlled based on the operation signal, and the hydraulic pressure applied to the blade cylinder 9a, the boom cylinder 24, the arm cylinder 25, the bucket cylinder 26, and the swing hydraulic motor 38. Supply control is performed, and the operation of the shovel mechanism 12 and the turning operation of the revolving structure 11 are performed. At this time, when revolving is stopped, energy is regenerated by the regenerative generator 39 to decelerate the turn, and the power generated by the regenerative power generator 39 in this way is supplied to the sub battery 44 via the sub charger 46. To charge this. Even at this time, the power control is performed from the main battery 41 to the pump drive motor 33 by the output control device 43 according to the operation, and the hydraulic pump 32 is driven by the motor 33 so that the hydraulic pressure is supplied to the control valve 34. Have been supplied.

  When the excavator vehicle 1 travels and works by the excavator mechanism 12 in this way, the power of the main battery 41 is consumed. Therefore, when the remaining capacity is reduced, the outlet 42a is connected to the commercial power source and is connected to the commercial power source. Electric power is supplied to the main battery 41 via the main charger 42 to be charged.

  On the other hand, the sub-battery 46 is not shown, but can be charged with electric power from a commercial power source via the sub-charger 46. Furthermore, as described above, the generated power of the solar panel 27 and the regenerative power generation The power generated by the machines 37 and 39 and the power generated by the hydraulic oil generator 35 are supplied via the sub-charger 46 and charged. Normally, the traveling of the power shovel vehicle 1 and the work by the shovel mechanism 12 are performed by driving the pump drive motor 33 by the power of the main battery 41. For this reason, there is almost no power consumption of the sub-battery 46. Since the generated power of the solar panel 27 or the like cannot be used for charging in the fully charged state, the sub-charger 46 supplies this generated power to the main battery 41. The main battery 41 is used for charging.

  When the power of the main battery 41 is consumed by the traveling of the power shovel 1 and the work by the shovel mechanism 12 and the remaining capacity is reduced, the sub battery 44 is connected to the main battery 41 by the connection switch 45, and The main battery 41 is charged by the battery 44. Alternatively, when the remaining capacity of the main battery 41 runs out, the connection switch 45 connects the sub battery 44 to the output control device 43, and the power of the sub battery 44 is controlled by the output control device 43 to the pump drive motor 33. Supply and drive this. As a result, when the remaining capacity of the main battery 41 is exhausted, the pump drive motor 33 is driven using the power of the sub-battery 44, and the left and right traveling mechanisms 3, 3 are driven to charge the power shovel vehicle 1. It is possible to take a measure of traveling to a place where the facility is located and charging the main battery 41 with this charging facility. Since the sub-battery 44 plays such a role, the capacity thereof is smaller than that of the main battery 41 as described above.

  Next, a modification of the embodiment of the present invention will be described with reference to FIG. In this embodiment, the traveling mechanism 3 is driven, that is, the driving sprocket wheel 5 is driven by the electric motor 51 so that the traveling device 2 travels. Further, the revolving unit 11 is driven to rotate by the electric motor 52. Since the configuration other than this is the same as the configuration of FIG. 2, the same parts are denoted by the same reference numerals and the description thereof is omitted.

  These electric motors 51 and 52 are constituted by motor generators, which are driven by power supply from the main battery 41 (or the sub-battery 44) via the output control device 43. The electric motor 51 acts as a generator upon receiving the deceleration force, and the generated power is supplied to the sub-battery 44 via the sub-charger 46 to charge it. Similarly, when the turning body 11 is decelerated and turned, the electric motor 52 acts as a generator upon receiving the deceleration force, and the generated power is supplied to the sub-battery 44 via the sub-charger 46 to charge it.

    The electric drive work vehicle according to the present invention is not limited to the configuration of only the electric drive method as described above, and may be a hybrid drive method including an engine for driving the traveling device and the hydraulic unit.

1 is a perspective view of a power shovel vehicle as an example of an electrically driven work vehicle according to the present invention. It is a block diagram of the hydraulic unit and power supply system concerning a 1st embodiment of the above-mentioned power shovel vehicle. It is a block diagram of the hydraulic unit and power supply system concerning a 2nd embodiment of the above-mentioned power shovel vehicle.

Explanation of symbols

1 Excavator vehicle (electrically driven work vehicle)
12 Excavator mechanism (working device)
27 Solar panel (photovoltaic means)
30 Hydraulic unit 33 Electric motor 34 for pump 34 Control valve 35 Hydraulic oil generator 37, 39 Regenerative generator 41 Main battery 44 Sub battery 45 Connection switcher

Claims (8)

A vehicle body capable of traveling with a traveling device;
A working device provided on the vehicle body;
A hydraulic unit for driving the working device;
An electric motor for driving the hydraulic unit;
An electrically driven work vehicle comprising: a main battery for driving the electric motor by supplying driving power to the electric motor ;
A sub-battery having a higher rated voltage than the main battery and capable of charging the main battery ;
And a connection switching means for selectively connecting the sub-battery to the electric motor and the main battery,
By the connection switching means, wherein the drivable electric motor Der by electric power supply to the sub-battery from the sub battery is connected to the electric motor Rutotomoni, the sub-battery to the sub battery is connected to the main battery An electrically driven work vehicle characterized in that the main battery can be charged by supplying electric power from the vehicle. Power generation means provided on the vehicle body;
Electrically driven working vehicle according to claim 1, characterized in Rukoto a sub-battery charging control means for charging the sub-battery generated electric power to be supplied is supplied to the sub-battery from the power generating means. The electrically driven work vehicle according to claim 2, wherein the power generation means is a solar power generation means that generates power by receiving solar energy . The power generating means, electrically driven working vehicle according to claim 2, characterized in that a driven energy the traveling device receives an energy recovery unit for regeneration. The power generating means, electrically driven working vehicle according to claim 2, characterized in that a hydraulic oil power generating means for generating power by being driven by a hydraulic fluid supplied from the hydraulic unit. Said body has a pivoting member provided pivotally on the traveling device,
The power generating means, electrically driven working vehicle according to claim 2, characterized in that a driven energy the rotating body receives the energy regenerating means for regenerating power. The sub-battery charging control means, wherein said when the sub-battery is fully charged state, the generated power supplied from the power generating means is supplied to said main battery, wherein the charging the main battery Item 7. The electrically driven work vehicle according to any one of Items 2 to 6.   The electrically driven work vehicle according to any one of claims 1 to 7, wherein the electric drive work vehicle is configured in a hybrid drive system including an engine that drives the traveling device and the hydraulic unit.

Images