JP5975838B2 - Electric work vehicle and cooling method for power supply device for electric work vehicle - Google Patents

Description

  The present invention relates to an electric work vehicle and a cooling method for an electric work vehicle power supply device.

  In recent years, motorization of work vehicles has progressed. In particular, a work vehicle such as a mine dump truck is required to have a high driving torque because it moves on a slope with a large gradient with high weight. Therefore, in such a vehicle, a shift from a mechanical type in which engine output is directly used for driving to driving to an electric type in which engine output is used for power generation and driven to drive by an electric motor is progressing.

  The electric work vehicle includes a power supply device for supplying power to the electric motor. In the power supply device, for example, a diode for rectifying the AC voltage generated from the generator using the engine output into a DC voltage, and an IGBT (used for an inverter that converts the DC voltage into an AC voltage supplied to the motor) Semiconductor elements such as Insulated Gate Bipolar Transistor) are used.

  When these semiconductor elements are operated, heat is generated, and the efficiency of the semiconductor elements is reduced by the heat. Therefore, it is necessary to cool the semiconductor elements.

  Since work vehicles such as dump trucks and construction machines are required to operate stably over a wide temperature range, it is necessary to appropriately cool the semiconductor elements of the power supply device. Among them, in particular, work vehicles such as mining dump trucks are used in harsh environments, and therefore energized portions including semiconductor elements are sealed and cooled by a water cooling method. In addition, although it is not a working vehicle, it is also known that a railway vehicle is cooled using a heat pipe.

JP 2011-233562 A JP 2005-123459 A

  In an electric work vehicle such as a dump truck, further weight reduction is desired in order to increase the loadable amount and improve fuel efficiency. However, when the power supply is cooled by the water cooling method, various components such as an antifreeze, a radiator, piping, and a pump are required, which increases the weight of the cooling structure and makes it difficult to reduce the weight of the vehicle.

  Therefore, it is conceivable to use heat pipe fins. The base end side of the heat pipe is embedded in the base on which the semiconductor element to be cooled is mounted. Due to the heat generated by the semiconductor element, the working fluid in the pipe evaporates on the proximal end side of the heat pipe, the steam moves to the low temperature part on the distal end side of the heat pipe, cools with the cooling air, condenses, and the working fluid passes through the pipe. It is transmitted and returns to the base end side. Since the heat pipe includes a plurality of cooling fins, it is called a heat pipe fin.

  The heat pipe fin has a high cooling capacity and is suitable for an electric work vehicle. However, since the work vehicle travels on a road with a large gradient, rough terrain, and the like, the vehicle tends to tilt. If the working fluid condensed on the front end side hardly returns to the base end side due to the tilting of the vehicle, the circulation of the working fluid in the heat pipe is hindered, so that the cooling efficiency is lowered.

  Accordingly, an object of the present invention is to provide an electric work vehicle and a method for cooling an electric work vehicle power supply device capable of suppressing a decrease in cooling efficiency due to the inclination of the vehicle body. Another object of the present invention is to provide an electric work vehicle and a method for cooling an electric work vehicle power supply device capable of improving impact resistance.

  In order to solve the above problems, an electric work vehicle according to the present invention is an electric work vehicle that travels by driving wheels by an electric motor, and includes at least one power supply device for supplying power to the electric motor. The power supply device is provided on at least one of the left and right sides with respect to the traveling direction of the vehicle body along the left and right direction with respect to the traveling direction, and a heat conduction member that releases heat absorbed at the proximal end side at the distal end side, and heat conduction At least a part of a power supply circuit for supplying power is provided on the base end side of the member.

  The electric motor includes a left electric motor for driving the left driving wheel and a right electric motor for driving the right driving wheel, and the power supply device includes a left power supply device for supplying power to the left electric motor, and a right electric motor. The left power supply device includes a right power supply device for supplying power to the left power supply device so that the front end side of the left heat conduction member of the left power supply device faces the front end side of the right heat conduction member of the right power supply device. And the right power supply device may be disposed opposite to the vehicle body.

  According to the present invention, since the heat conducting member for cooling at least a part of the power supply circuit is provided along the left-right direction with respect to the traveling direction, the cooling efficiency of the heat conducting member is improved even when the vehicle body is tilted back and forth or left and right. Can be suppressed.

  According to the present invention, the left and right heat conductive members are divided into the left heat conductive member and the right heat conductive member to cool the power supply devices arranged on both the left and right sides. Can be shortened. Accordingly, it is possible to withstand an impact when traveling on a rough road.

It is explanatory drawing which concerns on 1st Example and looked at the dump truck as an electrically-driven working vehicle from back. It is explanatory drawing which shows the relationship between a wind tunnel part and a heat pipe fin. It is explanatory drawing which shows that arrangement | positioning of a heat pipe fin inclines according to the inclination of the vehicle body of a dump truck. It is explanatory drawing which shows the state which the dump truck inclines. It is explanatory drawing which concerns on 2nd Example and looked at the dump truck from back. It is explanatory drawing which concerns on 3rd Example and looked at the dump truck from back. It is explanatory drawing which shows the structure of a heat pipe fin. It is explanatory drawing which looked at the dump truck from back regarding 4th Example. It is explanatory drawing which looked at the dump truck from back concerning 5th Example. It is explanatory drawing which looked at the dump truck from back regarding 6th Example.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the present embodiment, as will be described in detail below, an electric work vehicle having a power supply device that has a high adaptability to the inclination of the vehicle body and can appropriately maintain the cooling capacity is proposed. Moreover, in this embodiment, the electric work vehicle provided with the power supply device strong also to the impact which arises on a rough road driving | running is proposed.

  The first embodiment will be described with reference to FIGS. FIG. 1 is an explanatory view of a dump truck 1 as an “electric work vehicle” according to the present embodiment as viewed from the rear.

  The dump truck 1 includes a vehicle body 2 provided with a driver's cab (not shown), a frame 3 provided on the lower side of the vehicle body 2, front and rear wheels provided on the front, rear, left and right of the frame 3, and front wheels and / or rear wheels. And an electric motor 10 to be described later.

  In this embodiment, the rear-wheel drive type dump truck 1 is taken as an example, but a front-wheel drive type or a system in which all wheels are driven may be used. Drive wheels 4L and 4R are provided on the rear side of the body frame 3 so as to be located on both the left and right sides. The drive wheels 4L and 4R are driven by respective electric motors 5L and 5R. Unless otherwise distinguished, they may be referred to as drive wheels 4 and electric motors 5. The dump truck 1 travels on the ground R by driving the drive wheels 4 with the electric motor 5.

  The power supply device 10 electrically connects the inverter circuit 12 as a “power supply circuit”, the heat pipe fin device 11 as a “heat conducting member” for cooling each inverter circuit 12, and the inverter circuit 12 and the electric motor 5. Electrical wiring 13 for carrying out.

  FIG. 1 shows an electric circuit from the inverter circuit 12 to the electric motor 5. In this embodiment, in order to explain the case of using a three-phase AC motor, an inverter circuit 12, a heat pipe fin device 11, and an electrical wiring 13 are provided for each of the U phase, the V phase, and the W phase. Instead of this, other types of electric motors such as a DC electric motor and a single-phase AC motor may be used.

  In this embodiment, a case where an IGBT is used for the inverter circuit 2 will be described. Instead, a SiC MOS FET (Metal-Oxide-Semiconductor Field-Effect Transistor) or GTO (Gate Turn Off Thyristor) may be used. Any element that can handle a high breakdown voltage and a large current is applicable.

  In this embodiment, the inverter circuit 2 is assumed to have a structure in which two U-phase, V-phase, and W-phase upper and lower IGBTs are mounted on the heat pipe fin device 11. Alternatively, all IGBT elements may be mounted on one heat pipe fin device 11, or only one IGBT element may be mounted on one heat pipe fin device 11. good. If a predetermined function is obtained, the correspondence between the number of elements of the heat pipe fin device 11 and the inverter circuit 2 is not limited to that shown in FIG.

  In addition, although illustration is abbreviate | omitted, in the electric circuit of the dump truck 1, for example, a diode element for rectifying the generated power from the generator that generates power by the engine output into direct current, and the regenerative power obtained by the regenerative brake is a direct current capacitor In addition, a chopper circuit or the like for suppressing an increase in DC voltage can be provided. These circuit elements may also be cooled by the heat pipe fin device 11, or may be cooled using normal air-cooling fins when the heat generation amount is small.

  Furthermore, in the present embodiment, it is assumed that a plurality of film capacitors are used for the DC capacitor of the inverter circuit 2, but the present invention is not limited to this. Instead of the film capacitor, other circuit elements such as an electrolytic capacitor may be used.

  The heat pipe fin device 11 is a cooling structure including a plurality of heat pipe fins 110 as will be described later. In the present embodiment, three sets of the heat pipe fin device 11, the inverter circuit 12, and the electric wiring 13 are provided on both the left and right sides of the vehicle body 2 in correspondence with the left and right electric motors 5L and 5R. Further, in this embodiment, the assembly of the inverter circuit 12 and the heat pipe fin device 11 is arranged in multiple stages so as to overlap in the direction of gravity (Z-axis direction in the figure). Specifically, the assembly of the lowermost inverter circuit 12L and the heat pipe fin device 11, the assembly of the middle inverter circuit 12M and the heat pipe fin device 11, the uppermost inverter circuit 12U and the heat pipe are sequentially arranged from the bottom. The assembly of the fin device 11 is arranged along the direction of gravity. Unless otherwise distinguished, the inverter circuits 12L, 12M, and 12U may be referred to as the inverter circuit 12.

  The vehicle body 2 is provided with sealed spaces 20L and 20R on the left and right sides thereof. For example, a wind tunnel portion 22 through which outside air circulates during travel is provided at the center of the vehicle body 2. The sealed space portions 20L and 20R are formed by being blocked from the wind tunnel portion 22 by the partition wall portion 21. If there is no particular distinction, it may be called the sealed space 20. As will be described later, the inverter circuit 12 and the like are accommodated in the sealed space portion 20. The sealed space portion 20 is formed in a substantially sealed state using a seal member or the like in order to protect the inverter circuit 12 in the interior from external dust or moisture.

  The vehicle body 2 may be provided with a blower (not shown) for sending outside air as cooling air to the wind tunnel portion 22.

  The relationship between the wind tunnel part 22 and the heat pipe fin apparatus 11 is demonstrated using FIG. FIG. 2 is an explanatory diagram when the power supply device 10 is looked down from the upper side of the dump truck 1. The left and right heat pipe fin devices 11 are arranged opposite to the left and right sides of the vehicle body 2 with an axis line along the traveling direction (an axis line in the X direction in the figure) interposed therebetween.

  Each heat pipe fin device 11 includes a base portion 112 and a plurality of heat pipe fins 110 connected in parallel to the mounting surface of the base portion 112. A plurality of fins 111 are provided so as to connect the plurality of heat pipe fins 110.

  The base portion 112 is formed, for example, in a thin flat plate shape, and at least one of the two surfaces having the largest area among the six surfaces is an attachment surface 112A. One or a plurality of inverter circuits 12 are attached to the attachment surface 112A.

  A cooling passage (not shown) for cooling the inverter circuit 12 with a working fluid is formed inside the base portion 112. Of the four surfaces orthogonal to the mounting surface 112 </ b> A of the base portion 112, a plurality of heat pipe fins 110 are provided on the surface facing the wind tunnel portion 22 so as to extend into the wind tunnel portion 22.

  The proximal end side 110B of the heat pipe fin 110 is connected to the base portion 112, and the distal end side 110A of the heat pipe fin 110 extends into the wind tunnel portion 22 toward the axis along the traveling direction. The base portion 112 and the wind tunnel portion 22 are blocked by the partition wall portion 21. Accordingly, dust, moisture and the like in the wind tunnel portion 22 cannot enter the sealed space portion 20.

  A passage (not shown) through which hydraulic fluid flows is formed inside the heat pipe fin 110, and the passage communicates with a cooling passage in the base portion 112. The hydraulic fluid in the cooling passage of the base portion 112 takes heat from the inverter circuit 12 and vaporizes. The gas flows from the cooling passage of the base portion 112 through the passage of the heat pipe fin 110 and moves toward the front end side 110 </ b> A of the heat pipe fin 110.

  The gas generated by evaporation of the hydraulic fluid is cooled by the cooling air A <b> 1 flowing through the wind tunnel portion 22 while flowing through the passage of the heat pipe fin 110. At the front end side 110 </ b> A of the heat pipe fin 110, the gas condenses and returns to the liquid, and returns to the cooling passage in the base portion 112 through the passage of the heat pipe fin 110. The cooling air A1 that has flowed into the wind tunnel 22 takes heat from the heat pipe fin device 11 and flows out from the rear of the vehicle body 2 as cooling air A2.

  With reference to FIG. 3 and FIG. 4, the mounting angle of the heat pipe fin 110 and the state when the vehicle body is tilted will be described. On the upper side of FIG. 3, the dump truck 1 may travel on the substantially horizontal ground R, work on the substantially horizontal ground R, or stop on the substantially horizontal ground R.

  As described above, the left heat pipe fin device 11L and the right heat pipe fin device 11R are disposed so as to face each other with the axis in the traveling direction interposed therebetween, and are upwardly directed by a predetermined angle θ1 with respect to the horizontal plane (XY plane). It is attached.

  As shown in the lower side of FIG. 3 and FIG. 4, the dump truck 1 travels on the inclined ground R, works on the inclined ground R, or stops on the inclined ground R. For example, work vehicles such as large dump trucks and wheel loaders for mining often travel on rough roads or work on rough terrain.

  When the vehicle body 2 is inclined to the left side by an angle θ2 with respect to the horizontal plane, as shown in the lower side of FIG. 3, the angle of the left heat pipe fin device 11L with respect to the horizontal plane increases from θ1 to (θ1 + θ2). On the other hand, the angle of the right heat pipe fin device 11R with respect to the horizontal plane decreases from θ1 to (θ1−θ2).

  When the inclination angle θ2 of the ground R becomes equal to the mounting angle θ1 of the heat pipe fin device 11, the right heat pipe fin device 11R is substantially horizontal. That is, even if the vehicle body 2 is tilted to an angle θ2 equal to the mounting angle θ1 with respect to the horizontal plane of the heat pipe fin device 11, the working fluid can be circulated in the heat pipe fin device 11 and the cooling performance can be maintained. .

  When the vehicle body 2 is inclined at an angle θ1 or more, the distal end side 110A of the heat pipe fin 110 is positioned below the proximal end side 110B. For this reason, it becomes difficult for the hydraulic fluid condensed on the distal end side 110A to return to the proximal end side 110B, and the cooling performance may be reduced.

  In the present embodiment, as described above, the left and right heat pipe fin devices 11L and 11R are disposed upward from the horizontal plane by the attachment angle θ1, so that the heat pipe fin devices 11L and 11R are closer to each other than when horizontally disposed. be able to. Therefore, by attaching the heat pipe fin devices 11L and 11R at the predetermined attachment angle θ1, it is possible to cope with the inclination of the vehicle 2 and further reduce the size of the cooling structure.

  As shown in FIGS. 3 and 4, when the vehicle body 2 is tilted to the left, the torque of the left electric motor 5L for driving the left drive wheel 4L increases, so that power is supplied to the left electric motor 5L. The amount of current required for the inverter circuit 12 also increases. Therefore, the heat generation amount of the inverter circuit 12 corresponding to the left electric motor 5L increases. On the contrary, since the torque of the right electric motor 5R decreases, the amount of current required for the inverter circuit 12 that supplies power to the right electric motor 5R decreases. Accordingly, the amount of heat generated by the inverter circuit 12 corresponding to the right electric motor 5R decreases.

  As described below in FIG. 3, when the vehicle body 2 is inclined to the left by the angle θ2, the angle of the heat pipe fin device 11L for cooling the inverter circuit 12 corresponding to the left electric motor 5L with respect to the horizontal plane is (θ1 + θ2). To increase. By increasing the angle of the heat pipe fin device 11L with respect to the horizontal plane, the heat circulation speed in the heat pipe fin device 11L increases, and the heat resistance of the heat pipe fin device 11L decreases. Therefore, the cooling performance of the heat pipe fin device 11L is improved, and the inverter circuit 12 that generates a large amount of heat can be effectively cooled to suppress an increase in temperature.

  On the other hand, the heat pipe fin device 11R for cooling the inverter circuit 12 corresponding to the right electric motor 5R has a small angle with respect to the horizontal plane (θ1-θ2). Therefore, the heat circulation speed in the heat pipe fin device 11R is decreased, and the thermal resistance of the heat pipe fin device 11R is increased. However, since the load (current value) required for the inverter circuit 12 corresponding to the right electric motor 5R is small, the amount of heat generated by the inverter circuit 12 is also small. Even if the cooling performance of the heat pipe fin device 11R is reduced, the heat generation amount of the inverter circuit 12 in charge of the heat pipe fin device 11R is reduced, so that no inconvenience occurs.

  Therefore, according to the present embodiment, in the dump truck 1 in which the vehicle body 2 is likely to be inclined when traveling on rough roads or rough terrain, the cooling capacity corresponding to the temperature difference between the left and right inverter circuits 12 when the vehicle body is inclined is heated. This can be realized by the pipe fin device 11. For this reason, the temperature difference between the inverter circuits 12 corresponding to the left and right electric motors 5 can be reduced.

  Furthermore, in the present embodiment, the left and right heat pipe fin devices 11 are arranged on both the left and right sides of the vehicle body 2 so as to face each other across the axis X along the traveling direction of the vehicle body 2. Therefore, even when the dump truck 1 goes down a steep mountain road, the cooling capacity of the heat pipe fin device 11 can be maintained.

  Here, consider the case where the heat pipe fin device is arranged along the front-rear direction (traveling direction) of the vehicle body. The proximal end side of the heat pipe fin device is located on the rear side in the front-rear direction, and the distal end side of the heat pipe fin device is located on the front side in the front-rear direction. When the dump truck 1 climbs a mountain road, the distal end side of the heat pipe fin device is lifted and the proximal end side of the heat pipe fin device is sunk, so that the cooling capacity of the heat pipe fin device is increased.

  On the other hand, when the dump truck 1 goes down the mountain road, the distal end side of the heat pipe fin device sinks and the proximal end side of the heat pipe fin device lifts. Therefore, the cooling capacity of the heat pipe fin device is reduced.

  In the present embodiment, the left and right heat pipe fin devices 11 are arranged to face each other so as to be substantially orthogonal to the traveling direction of the vehicle body 2, so that the influence on the gradient in the traveling direction of the vehicle body 2 can be suppressed.

  Furthermore, in this embodiment, a plurality of heat pipe fin devices 11 are arranged in multiple stages in the direction of gravity. Therefore, it is possible to efficiently cool the heat pipe fin device 11 by applying the cooling air A1 flowing in the wind tunnel portion 22 to each heat pipe fin device 11 efficiently. On the other hand, when the heat pipe fin device 11 is arranged back and forth along the traveling direction, it is impossible to efficiently apply cold air to the downstream heat pipe fin device 11, and the downstream heat pipe fin device 11. 11 cooling performance is reduced. In this embodiment, since the plurality of heat pipe fin devices 11 are arranged in multiple stages in the direction of gravity so as to be perpendicular to the flow of the cooling air, each heat pipe fin device 11 can be air-cooled equally, and the inverter The temperature difference of the circuit 12 can be reduced.

  Furthermore, in this embodiment, since the plurality of heat pipe fin devices 11 are arranged in multiple stages in the direction of gravity, mechanical rigidity can be increased by connecting the heat pipe fin devices 11 with attachment stays or the like. Therefore, even when the dump truck 1 travels on a rough road and a strong vertical vibration or impact is applied to the vehicle body 2, the heat pipe fin device 11 can withstand the vibration or impact. Thereby, the impact resistance and reliability of the heat pipe fin apparatus 11 can be improved.

  Furthermore, in this embodiment, the wind tunnel portion 22 is provided in the center of the vehicle body 2, and the inverter circuit 12 is disposed in the sealed space portion 20 formed on the left and right sides so as to sandwich the wind tunnel portion 22. Thereby, compared with the case where the inverter circuit 12 is arrange | positioned adjacently, the distance between the inverter circuits 12 can be lengthened. Therefore, the wiring impedance between the inverter circuits 12 can be increased, and the current (cross current) flowing between the inverter circuits 12 can be suppressed.

  A second embodiment will be described with reference to FIG. Each of the following embodiments, including the present embodiment, corresponds to a modification of the first embodiment, and therefore, differences from the first embodiment will be mainly described. In the present embodiment, the heat pipe fin device 11A included in the power supply device 10A is arranged in parallel to the horizontal plane.

  FIG. 5 is an explanatory diagram showing an electrical configuration from the inverter circuit 12 to the electric motor 5 when the dump truck 1 is viewed from the rear. The heat pipe fin device 11A arranged opposite to the left and right of the vehicle body 2 is configured in the same manner as described in FIGS. 2 and 3, but the mounting angle is different. Each heat pipe fin 110 of the heat pipe fin apparatus 11A is configured to be parallel to a horizontal plane.

  In the present embodiment, for example, as shown in FIG. 4, when the dump truck 1 is tilted to the left side, in the heat pipe fin device 11A corresponding to the electric motor 5R on the side where the torque does not increase, the tip side 110A is below the horizontal plane. Located on the side. Therefore, in the heat pipe fin device 11A on the right side, the circulating amount of the hydraulic fluid is reduced and the thermal resistance is increased. Thereby, the temperature drop of the inverter circuit 12 corresponding to the right electric motor 5R can be reduced.

  In the case of the first embodiment, in FIG. 4, the cooling performance of the heat pipe fin device 11 corresponding to the right electric motor 5R does not deteriorate. Accordingly, the inverter circuit 12 corresponding to the right electric motor 5R is efficiently cooled despite the load (current) being reduced and the heat generation amount being reduced. When the dump truck 1 travels or works for a long time while tilting in the same direction, the temperature of the inverter circuit 12 corresponding to the right electric motor 5R may be too low. In such a case, the temperature difference between the left and right inverter circuits 12 can be reduced by adopting the configuration of the present embodiment.

  A third embodiment will be described with reference to FIGS. In the present embodiment, the heat pipe fin device 11B of the power supply device 10B has the heat pipe fin 110 attached perpendicular to the element attachment surface of the base portion 112. In this embodiment, 90 degrees is given as an example of the “predetermined angle”, but instead, for example, the heat pipe fin may be attached to the element mounting surface of the base portion in the range of 1 to 89 degrees or 30 to 60 degrees. Good.

  FIG. 6 is an explanatory diagram showing an electrical configuration from the inverter circuit 12 to the electric motor 5 when the electric dump truck 1 is viewed from the rear, as in the above embodiments. As described in the first embodiment, the heat pipe fin device 11B is positioned opposite to the left and right sides of the vehicle body 2, and the heat pipe fin 110 is mounted upward by a predetermined mounting angle θ1 from the horizontal plane.

  FIG. 7 is a plan view of the left and right heat pipe fin devices 11 </ b> B as viewed from above the dump truck 1. Of the six surfaces of the base portion 112, one of the two surfaces with the largest area is an element mounting surface 112A for mounting an element, and the other is a heat pipe fin for mounting each heat pipe fin 110 vertically. It is a mounting surface 112B. Furthermore, in this embodiment, a plurality of heat pipe fins 110 are arranged for each of the semiconductor elements 14 attached to the element attachment surface 112A. That is, the plurality of heat pipe fins 110 included in the heat pipe fin device 11B are grouped for each semiconductor element 14 and are responsible for cooling the corresponding semiconductor elements 14 respectively.

  In this embodiment, since the heat pipe fins 110 are vertically attached to the base portion 112, the size in the lateral direction of the power supply device 10B can be reduced as compared with the configuration shown in FIG. In particular, since the length dimension from the front end side 110A of the heat pipe fin 110 to the element mounting surface 112A of the base portion 112 can be made shorter than the configuration shown in FIG. 2, the mechanical strength of the heat pipe fin device 11B can be increased. it can. Thereby, even when mounted on the dump truck 1 used on rough roads or rough terrain, the cooling performance and reliability can be maintained.

  A third embodiment will be described with reference to FIG. In the present embodiment, a case will be described in which circuits other than the inverter circuit 12 are arranged in the left and right sealed spaces 20 (which may be referred to as device housing chambers), and the other circuits are cooled.

  FIG. 8 shows an electrical configuration of the electric dump truck 1 as viewed from the rear. The power supply device 10C includes a heat pipe fin 11B, an inverter circuit 12, a left electric motor 5L, a right electric motor 5R, a converter and chopper circuit 15, and an in-panel cooling device 16.

  The converter circuit has a function of converting electric power generated by a generator driven by engine output from AC to DC. The converter circuit and chopper circuit 15 are assumed to use diodes, but other elements such as IGBTs may be used as long as they have the same function as the diodes.

  The chopper circuit has a function of clamping in order to keep the DC voltage below a certain level during regenerative braking in the left electric motor 5L and the right electric motor 5R. The electric power regenerated at the time of braking is consumed by the grid resistance, etc. outside the figure. The chopper circuit is assumed to use a diode and an IGBT, but other elements may be used.

  The panel cooling device 16 has a function of reducing the temperature in the sealed space 20 (in the panel), and a heat pipe fin and a fan for blowing air in the panel to the heat pipe fin. With. Unlike the air conditioner or the like, the in-panel cooling device 16 does not cause condensation due to cooling in the sealed space 20.

  The present embodiment discloses a configuration for cooling the inside of the sealed space 20 and can be combined with each of the above-described embodiments. In the present embodiment, since the temperature of the sealed space 20 can be lowered, the inverter circuit 12 and other circuits 15 can be effectively cooled.

  A fifth embodiment will be described with reference to FIG. In the power supply device 10 </ b> D of the present embodiment, the left and right heat pipe fin devices 11 </ b> C are connected in the wind tunnel portion 22. FIG. 9 is an explanatory diagram showing an electrical configuration when the electric dump truck 1 is viewed from the rear.

  On both the left and right sides of the vehicle body 2, heat pipe fin devices 11C are arranged to face each other. Each heat pipe fin 110 is attached upward by a predetermined angle from the horizontal plane. The heat pipe fins 110 facing each other in the wind tunnel portion 22 are connected to each other at the front end side 110 </ b> A through a connecting portion 113. That is, the passage in the left heat pipe fin 110 and the passage in the right heat pipe fin 110 are connected via a passage (not shown) in the connecting portion 113.

  In this embodiment, since the left and right heat pipe fin devices 11C are connected by the connecting portion 113, the temperature difference between the left and right inverter circuits 12 is further reduced when the dump truck 1 is tilted as shown in FIG. Can do.

  A sixth embodiment will be described with reference to FIG. This embodiment corresponds to a modification of the fourth embodiment, and the power supply device 10E of this embodiment is an inverter circuit 17 for supplying power to an auxiliary machine such as a blower for sending cooling air to the wind tunnel portion 22. Is provided.

  FIG. 10 is an explanatory diagram of an electrical configuration when the electric dump truck 1 is viewed from the rear. The auxiliary drive inverter circuit 17 is located above the wind tunnel portion 22 and is provided in a sealed space portion 20 </ b> C formed in the vehicle body 2. The inverter drive inverter circuit 17 includes a heat sink, and the heat sink is exposed in the wind tunnel portion 22.

  The auxiliary drive inverter circuit 17 may be a three-phase AC circuit, a single-phase AC circuit, or a DC circuit.

  The auxiliary drive inverter circuit 17 converts electric power far smaller than the inverter circuit 12 that converts high electric power. Therefore, the heat pipe fin device is not used for cooling the inverter circuit 17. Therefore, in this embodiment, the inverter circuit 17 is air-cooled with a heat sink.

In addition, this invention is not limited to the Example mentioned above. A person skilled in the art can make various additions and changes within the scope of the present invention. For example, the present invention can be grasped as a power supply device as follows.
“Expression 1. A power supply device that supplies power to an electric motor of an electric work vehicle,
A heat conducting member that is provided on at least one of the left and right sides of the vehicle body in the running direction along the left-right direction with respect to the running direction, and that releases heat absorbed at the base end side at the tip side;
At least a part of a power supply circuit for supplying the power is provided on the base end side of the heat conducting member.
Power supply device for electric work vehicles.
Expression 2. The wheels of the power work vehicle include a left drive wheel and a right drive wheel,
The electric motor includes a left electric motor for driving the left driving wheel and a right electric motor for driving the right driving wheel,
The power supply device includes a left power supply device for supplying power to the left electric motor, and a right power supply device for supplying power to the right electric motor,
The left power supply device and the right power supply device are arranged to face the vehicle body so that the front end side of the left heat conductive member of the left power supply device faces the front end side of the right heat conductive member of the right power supply device. ,
The power supply device for an electric work vehicle according to expression 1. "

  In each of the above embodiments, an electric work vehicle such as a dump truck has been described as an example. However, the present invention is not limited to this, and any electric vehicle used on mountain roads, rough roads, rough terrain, private vehicles, buses, It can also be applied to other vehicles such as trucks. Therefore, the expression “electric work vehicle” in the description of the present invention may be replaced with another expression such as “electric vehicle”.

  1: dump truck, 2: vehicle body, 3: frame, 4L, 4R: drive wheel, 5L, 5R: electric motor, 10, 10A to 10E: power supply device, 11, 11L, 11R, 11A to 11C: heat pipe fin device 12, 12U, 12M, 12L: inverter circuit, 13: electrical wiring, 20L, 20R: sealed space, 22: wind tunnel, 110: heat pipe fin, 110A: distal end side, 110B: proximal end side, 112: base Part, R: ground

Claims (9)

An electric work vehicle that travels by driving wheels by an electric motor,
Comprising at least one power supply for supplying power to the electric motor;
The wheels include left drive wheels and right drive wheels,
The electric motor includes a left electric motor for driving the left driving wheel and a right electric motor for driving the right driving wheel,
The power supply device
A left power supply that supplies power to the left electric motor, and a right power supply that supplies power to the right electric motor,
Dissipates heat absorbed at the distal end side of the left power supply device by releasing the heat at the distal end side to cool the left heat conduction member, and releases the heat absorbed at the proximal end side of the right power supply device at the distal end side. Is arranged on the vehicle body so as to face the front end side of the right heat conductive member for cooling by sandwiching the longitudinal central axis along the traveling direction of the vehicle body,
In the vehicle body, air flows so as to include at least a space where the front end side of the left heat conductive member and the front end side of the right heat conductive member are opposed to each other with a longitudinal central axis along the traveling direction of the vehicle body. A wind tunnel,
The left and right sides of the vehicle body are provided with a left sealed space portion and a right sealed space portion that are blocked from the wind tunnel portion,
The base end side of the left heat conducting member is disposed in the left sealed space,
The base end side of the right heat conduction member is disposed in the front right side sealed space,
Electric work vehicle. The left heat conduction member and the right heat conduction member are opposed to each other with a longitudinal center axis along the traveling direction of the vehicle body, and the front end sides thereof are directed upward by a predetermined angle with respect to a horizontal plane. Provided in the
The electric work vehicle according to claim 1 . The left heat conductive member and the right heat conductive member are opposed to each other across the longitudinal central axis of the vehicle body, and are provided on the vehicle body along a horizontal plane.
The electric work vehicle according to claim 1 . A plurality of each of the left heat conductive member and the right heat conductive member are provided,
The plurality of left side heat conductive members and the plurality of right side heat conductive members are arranged in multiple stages along the direction of gravity.
The electric work vehicle in any one of Claims 1-3 . The base end side of the left heat conductive member is connected to a left base portion on which at least a part of the power supply circuit of the left power supply device is mounted,
The base end side of the right heat conductive member is connected to a right base portion on which at least a part of the power supply circuit of the right power supply device is mounted,
The left heat conducting member is attached in parallel to the plane of the left base portion,
The right heat conducting member is mounted in parallel to the plane of the right base portion;
The electric work vehicle in any one of Claims 1-3 . The base end side of the left heat conductive member is connected to a left base portion on which at least a part of the power supply circuit of the left power supply device is mounted,
The base end side of the right heat conductive member is connected to a right base portion on which at least a part of the power supply circuit of the right power supply device is mounted,
The left heat conducting member is attached to the plane of the left base portion at a predetermined angle,
The right heat conduction member is attached to the plane of the right base portion at a predetermined angle;
The electric work vehicle in any one of Claims 1-3 . The leading end side of the left heat conducting member and the leading end side of the right heat conducting member communicate with each other via a communicating member located in the wind tunnel portion.
The electric work vehicle in any one of Claims 1-3 . A method for cooling a power supply for an electric work vehicle,
The power supply device includes a left power supply device that supplies power to the left electric motor for driving the left drive wheel, and a right power supply device that supplies power to the right electric motor for driving the right drive wheel. And
A left heat conducting member for cooling said left power supply, and a right heat conducting member for cooling said right power supply device, each of the tip side opposite to each other across the central axis along the traveling direction of the car body In the car body,
Supplying cooling air to a predetermined wind tunnel including at least a space where the front end side of the left heat conductive member and the front end side of the right heat conductive member face each other;
A cooling method for a power supply device for an electric work vehicle. An electric work vehicle that travels by driving wheels by an electric motor,
The power supply apparatus that supplies power to the electric motor supplies power to the left power supply apparatus that supplies power to the left electric motor for driving the left drive wheel and the right electric motor that drives the right drive wheel. Right side power supply and
The left heat conducting member for cooling the left power supply device and the right heat conducting member for cooling the right power supply device are opposed to each other with their front end sides sandwiching the central axis along the traveling direction of the vehicle body. Placed on the car body,
Cooling air is supplied to a predetermined wind tunnel including at least a space where the front end side of the left heat conductive member and the front end side of the right heat conductive member face each other.
Electric work vehicle.

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