Dump truck

Abstract

To provide a dump truck that can suppress a decrease in heat exchange efficiency by providing a structure for suppressing air re-circulation between an exhaust path and an intake path.SOLUTION: At a position between a front face and a side face outside a heat exchanger (left heat exchanger 117A, right het exchanger 117B), a blockage member (left blockage member 120A, right blockage member 120B) which blocks flow of exhaust air discharged from the side face toward the front face is provided. More specifically, the blockage member (left blockage member 120A, right blockage member 120B) which suppresses circulation is located between a side face of the heat exchanger on a vehicle structure side (vehicle center side) and a side face of a vehicle structure opposite to (facing) the aforesaid side face.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a dump truck, and more particularly to a dump truck having a structure that prevents high-temperature exhaust gas from returning (circulating) to the intake side after heat exchange in a heat exchanger mounted on a fender. [Background technology]

[0002] A dump truck is known that includes an engine, at least one fan that draws in outside air to generate cooling air, and a heat exchanger that exchanges heat between a refrigerant circulating inside the engine and the cooling air (see, for example, Patent Document 1). The heat exchanger cools the refrigerant by absorbing heat stored in the refrigerant into the cooling air (outside air) and dissipating it. The heat exchanger is mounted on the front of the vehicle with its front side open forward (in the direction of travel) so that outside air can be easily drawn into the interior by the wind generated by the dump truck's travel. As such, in dump trucks equipped with an engine, the heat exchanger is often mounted on the front center of the vehicle just in front of the engine. However, depending on the power unit (hereinafter also referred to as the power source), the power unit may approach this position, leaving no space for the heat exchanger. In such cases, it may be possible to relocate the heat exchanger to the front of the fender on the side of the vehicle. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2018-043554 Summary of the Invention [Problem to be solved by the invention]

[0004] From the perspective of heat exchange efficiency, it is preferable for such dump truck heat exchangers to have a front intake / rear exhaust configuration, in which outside air is taken in from the front and exhausted from the rear (back). However, if the heat exchanger is relocated to the front of the fender and an exhaust port is provided on the fender behind the heat exchanger, the exhaust port may be clogged with dust kicked up by the tires. Therefore, if the heat exchanger is relocated to the front of the fender, a side exhaust configuration is used, where there is less dust. With a side exhaust configuration, there is nothing obstructing the exhaust path on the outside of the vehicle, but there are vehicle structures on the inside of the vehicle, and after the exhaust hits the vehicle structure, it may be re-intaken, circulating back into the intake port on the front of the heat exchanger. When such re-intaken air occurs, the intake air temperature rises, reducing the difference with the exhaust temperature and reducing heat exchange efficiency.

[0005] The present invention has been made in consideration of the above circumstances, and aims to provide a dump truck that can suppress a decrease in heat exchange efficiency by providing a structure that suppresses re-intake between the exhaust path and the intake path. [Means for solving the problem]

[0006] In order to solve the above problem, the dump truck of the present invention is a dump truck comprising a body having wheels, a drive unit including a power source for operating the body, a fender covering the wheels, and a heat exchanger provided on the front of the fender, which takes in outside air from the front and discharges it from the side, and regulates the temperature of a heat medium for regulating the temperature of the drive unit, and is characterized in that a blocking member is provided on the outside of the heat exchanger at a position between the front and the side, which blocks the flow of exhaust gas discharged from the side toward the front. [Effects of the Invention]

[0007] According to the present invention, by providing a blocking member between the exhaust path and the intake path as a structure for suppressing re-intake of air, it is possible to suppress a decrease in heat exchange efficiency. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a perspective view showing the appearance (overall configuration) of a dump truck according to an embodiment of the present invention. [Figure 2] 2 is a perspective view showing the dump truck of FIG. 1 with the loading platform removed. FIG. [Figure 3] FIG. 3 is a front view of the dump truck of FIG. 2. [Figure 4A] FIG. 4 is an enlarged perspective view showing the detailed structure of the left heat exchanger and its surroundings and the exhaust path. [Figure 4B] FIG. 4 is an enlarged perspective view showing a detailed structure around the right heat exchanger and an exhaust path. [Figure 5A] FIG. 10 is a top view schematically showing the intake path and the exhaust path when there is no blocking member. [Figure 5B] FIG. 10 is a top view schematically showing an intake path and an exhaust path when a blocking member is present. [Figure 6] FIG. 1 is a diagram showing a temperature control circuit mounted on a dump truck. [Figure 7] 1 is a table showing an example of power distribution between left and right passive or active heat exchangers. [Figure 8] A table showing an example of power distribution between left and right passive or active heat exchangers (when the power exceeds 100% of the rated power). [Figure 9] Table showing an example of fan power distribution in a passive heat exchanger. [Figure 10] 10 is a table showing an example of heater output distribution in an active temperature control circuit. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Components with the same reference numerals in each drawing have the same functions unless otherwise specified, and the description thereof will be omitted.

[0010] Fig. 1 is a perspective view showing the appearance (overall configuration) of a dump truck 100. Fig. 2 is a perspective view showing the dump truck of Fig. 1 with the bed removed. Fig. 3 is a front view of the dump truck of Fig. 2. Fig. 3 schematically shows the intake path and exhaust path of the heat exchanger.

[0011] The dump truck 100 is an electric dump truck equipped with a chargeable and dischargeable power storage device 110 as a power source for traveling. The dump truck 100 is, for example, a dump truck (mining truck) that transports earth and sand, minerals, etc. excavated in an open-cut mine.

[0012] The dump truck 100 is composed of front wheels 101, rear wheels 102, and a sturdy body frame 104 connected to the front wheels 101 and rear wheels 102. A loading platform (also called a body, vessel, etc.) 105 for loading earth and sand is mounted on top of the body frame 104. The body frame 104 is provided with a hoist cylinder (not shown) for tilting the loading platform 105 relative to the body frame 104 when dumping earth. The loading platform 105 rises and falls vertically around a hinge pin at the rear of the body frame 104 as the hoist cylinder extends and retracts. One end of the hoist cylinder is connected to the body frame 104 and the other end is connected to the loading platform 105, and the hoist cylinder extends and retracts by receiving hydraulic oil from a hydraulic pump (not shown). The hydraulic pump is driven by a hydraulic pump motor 106 (FIG. 6), which is an electric motor. When the hoist cylinder extends, the loading platform 105 rises, and when the hoist cylinder retracts, the loading platform 105 falls down. A pair of left and right front wheels 101 and rear wheels 102 are rotatably supported on the front and rear parts of the body frame 104. The front wheels 101 are steering wheels, and the rear wheels 102 are drive wheels, and a travel motor (not shown) is provided on the rotating shaft of the rear wheels 102. The travel motor is an electric motor that is rotated by receiving power from an electricity storage device 110, which is a power source. In addition, the front wheels 101 and the rear wheels 102 are provided with braking devices 103 (FIG. 6) for slowing down or stopping the vehicle body. A deck 107 on which an operator can walk and an operator's cabin (also called a cab) 108 in which the operator sits are provided on the upper front part of the body frame 104.

[0013] The dump truck 100 is equipped with a power storage device (also referred to as a battery) 110 as a main device (main engine) for moving the vehicle body, and a DC / DC converter 111 (FIG. 6) that controls the charge / discharge operation of the power storage device 110 by stepping down or stepping up the input / output voltage of the power storage device 110 to a predetermined voltage. The power storage device 110 and the DC / DC converter 111 are provided as a high-voltage system of about several thousand volts.

[0014] The dump truck 100 is equipped with auxiliary machinery other than the main engine, such as an air conditioning unit (not shown) that adjusts the temperature and humidity of the air in the cab 108, and a heater (not shown) that heats the heat medium supplied to the air conditioning unit. The air conditioning unit and the heater are provided as low-voltage systems of about several tens of volts.

[0015] The power storage device 110 is disposed in the front part of the body frame 104 of the dump truck 100. More specifically, a plate-shaped grill is provided in the center front part of the body frame 104 to protect equipment behind it, and the power storage device 110 is disposed behind the grill. The power storage device 110 is made up of a plurality of units, and the units are disposed in a stacked manner in the vertical direction. The DC / DC converter 111 is disposed in the center part of the body frame 104, behind the power storage device 110.

[0016] A building 112 for accommodating the above-mentioned power storage device 110 and the like is provided at the front of the body frame 104 of the dump truck 100. The building 112 is a vehicle structure made up of a flat left side surface member 112A arranged along the left side surface of the rectangular power storage device 110, a flat right side surface member 112B arranged along the right side surface of the power storage device 110, and a flat top surface member 112C arranged along the top surface of the power storage device 110 and bridging between upper ends of the left side surface member 112A and the right side surface member 112B. The power storage device 110 is connected to the building 112 (to the inner surfaces of the left side surface member 112A and the right side surface member 112B) and is supported by the building 112 together with the body frame 104.

[0017] A deck 107 and an operator's cab (cab) 108 are attached to and supported on the upper part of the outer surface (left side) of a left side member 112A of the building 112. A flat left fender 113A that covers approximately the upper half of the front side of the left front wheel 101 is attached to and supported on the front part of the underside of the deck 107 on the outer surface (left side) of the left side member 112A of the building 112. The left fender 113A extends downward from the underside of the deck 107 and protrudes outward (to the left) from the outer surface (left side) of the left side member 112A of the building 112 to prevent scattering of dust kicked up by the dump truck 100 when the dump truck 100 is traveling (when the front wheel 101 is rotating). The left fender 113A extends in a direction approximately perpendicular to the traveling direction (front-to-rear direction) in front of the left front wheel 101 and offset rearward from the front end of the left side member 112A.

[0018] A frame body 109 serving as a base is attached to and supported on the upper part of the outer surface (right side surface) of the right side surface member 112B of the building 112. A right fender 113B covering approximately the upper half of the front side of the right front wheel 101 is attached to and supported on the front part of the underside of the frame body 109 on the outer surface (right side surface) of the right side surface member 112B of the building 112. The right fender 113B extends downward from the underside of the frame body 109 and protrudes outward (to the right) from the outer surface (right side surface) of the right side surface member 112B of the building 112 to prevent scattering of dust kicked up by the dump truck 100 when the dump truck 100 is traveling (when the front wheel 101 is rotating). The right fender 113B extends in a direction approximately perpendicular to the traveling direction (front-to-rear direction) at a position in front of the right front wheel 101 and offset rearward from the front end of the right side surface member 112B and the frame body 109.

[0019] A coolant tank 114 (see FIG. 2, etc.) that stores coolant as a heat medium and a pump (see FIG. 6) that circulates the coolant to each device are provided at the front of the body frame 104 of the dump truck 100 and ahead of the power storage device 110, i.e., at the front end of the body frame 104. The coolant passes from the discharge side of the pump through the power storage device 110, the drive devices and auxiliary devices for operating the vehicle body such as the DC / DC converter 111, and the coolant tank 114 in this order, and then circulates to the suction side of the pump, thereby regulating (cooling) the temperatures of the drive devices and auxiliary devices such as the power storage device 110 and the DC / DC converter 111 (also see FIG. 6). The pump is operated by rotation of an electric motor that is driven by power supplied from the power storage device 110 or a low-voltage auxiliary battery different from the power storage device 110. The pump is provided behind the coolant tank 114, i.e., between the coolant tank 114 and the power storage device 110.

[0020] The coolant tank 114 includes an active tank 115 that stores coolant that mainly regulates (cools) the temperature of the power storage device 110, and a passive tank 116 that stores coolant that regulates (cools) the temperature of drive devices other than the power storage device 110, such as the DC / DC converter 111 (see FIG. 2, etc.). The active tank 115 and the passive tank 116 are divided into left and right tanks and arranged at the front end of the body frame 104. The active tank 115 and the passive tank 116 of the coolant tank 114 are connected to a left heat exchanger 117A and a right heat exchanger 117B that are provided on the left and right sides of the front of the dump truck 100, respectively. The coolant in the active tank 115 and the passive tank 116 of the coolant tank 114 is cooled by the left heat exchanger 117A and the right heat exchanger 117B.

[0021] A substantially rectangular left heat exchanger 117A is provided on the front surface of the left fender 113A of the dump truck 100. The left heat exchanger 117A is provided on the front surface of the left fender 113A at a distance from both the underside of the deck 107 and the outer surface (left side surface) of the left side surface member 112A of the building 112 (also see FIG. 4A).

[0022] A substantially rectangular right heat exchanger 117B is provided on the front surface of the right fender 113B of the dump truck 100. The right heat exchanger 117B is provided on the front surface of the right fender 113B, spaced apart (with a gap) from both the underside of the frame 109 and the outer surface (right side surface) of the right side surface member 112B of the building 112 (also see FIG. 4B ).

[0023] The power storage device 110, and the left heat exchanger 117A and the right heat exchanger 117B, which are respectively provided on the left and right sides of the power storage device 110 via the building 112, have their fronts open forward so that they can be easily cooled by the wind generated by the dump truck 100 traveling.

[0024] The left heat exchanger 117A and the right heat exchanger 117B have almost the same basic configuration. The left heat exchanger 117A and the right heat exchanger 117B are each a front intake / side exhaust heat exchanger that takes in outside air from the front into the interior (heat exchanger main body) and exhausts it from the left and right side surfaces (both side surfaces). The front surfaces of the left heat exchanger 117A and the right heat exchanger 117B are intake surfaces and include, for example, intake ports with multiple slits. The left and right side surfaces of the left heat exchanger 117A and the right heat exchanger 117B are exhaust surfaces and include, for example, exhaust ports with multiple slits.

[0025] The left heat exchanger 117A includes a left active heat exchanger 118A that mainly cools the coolant that regulates (cools) the temperature of the power storage device 110, and a left passive heat exchanger 119A that cools the coolant that regulates (cools) the temperature of drive devices other than the power storage device 110, such as the DC / DC converter 111. In the left heat exchanger 117A, the left active heat exchanger 118A is disposed on the upper side and the left passive heat exchanger 119A is disposed on the lower side, stacked one on top of the other. The left active heat exchanger 118A and the left passive heat exchanger 119A are each heat exchangers with front intake and side exhaust as described above. The left active heat exchanger 118A and the left passive heat exchanger 119A are respectively connected to the active tank 115 and the passive tank 116 that are provided in a left and right divided section at the front of the dump truck 100. The left active heat exchanger 118A and the left passive heat exchanger 119A cool the coolant in the active tank 115 and the passive tank 116, respectively.

[0026] Like the left heat exchanger 117A, the right heat exchanger 117B includes a right active heat exchanger 118B that cools the coolant that mainly regulates (cools) the temperature of the power storage device 110, and a right passive heat exchanger 119B that cools the coolant that regulates (cools) the temperature of drive devices other than the power storage device 110, such as the DC / DC converter 111. In the right heat exchanger 117B, the right active heat exchanger 118B is disposed on the upper side and the right passive heat exchanger 119B is disposed on the lower side, stacked one on top of the other. The right active heat exchanger 118B and the right passive heat exchanger 119B are each heat exchangers with front intake and side exhaust as described above. The right active heat exchanger 118B and the right passive heat exchanger 119B are respectively connected to the active tank 115 and the passive tank 116 that are provided in a left-right split at the front of the dump truck 100. The right active heat exchanger 118B and the right passive heat exchanger 119B cool the coolant in the active tank 115 and the passive tank 116, respectively.

[0027] As described above, if the heat exchanger is placed on the front of the fender and exhaust is discharged from the side of the heat exchanger, there is nothing obstructing the exhaust path to the outside of the vehicle, but there is a vehicle structure (building) on ​​the inside of the vehicle, and the exhaust hits the vehicle structure at the center of the vehicle, causing the exhaust pressure to rise between the side of the heat exchanger and the side of the vehicle structure.The pressurized exhaust then flows to the front of the heat exchanger, which is at low pressure, and is then taken in (re-intaken) from the intake surface on the front of the heat exchanger, reducing the heat exchange efficiency (see Figure 5A).

[0028] Therefore, on the left side of the dump truck 100 of this embodiment, a left shutoff member 120A is provided between the left heat exchanger 117A and the left side surface member 112A of the building 112. The left shutoff member 120A shuts off the flow of exhaust air discharged from the right side surface (inner surface) of the left heat exchanger 117A toward the front surface, thereby separating the exhaust path on that side from the intake path on the front surface. The left shutoff member 120A has a rectangular flat plate shape spanning the height of the left heat exchanger 117A in the vertical direction, with its outer end (left end) airtightly connected to the vicinity of the corner between the right side surface (inner surface) and the front surface of the left heat exchanger 117A and its inner end (right end) airtightly connected to the left surface (outer surface) of the left side surface member 112A of the building 112, and extending in a direction approximately perpendicular to the front-to-rear direction (traveling direction) (see FIG. 4A ).

[0029] The above-described left blocking member 120A prevents outside air (exhaust air) discharged from the right side surface (inner surface) of the left heat exchanger 117A from returning to the front surface via the space outside the side surface and being sucked in again (re-intake).The outside air (exhaust air) is discharged (guided) in the vertical direction from the right side surface (inner surface) of the left heat exchanger 117A, passing between the left heat exchanger 117A and the left side surface member 112A of the building 112 and between the left fender 113A and the left blocking member 120A, thereby maintaining heat exchange efficiency (see FIGS. 3, 4A, and 5B).

[0030] Furthermore, on the right side of the dump truck 100 of this embodiment, a right blocking member 120B is provided between the right heat exchanger 117B and the right side member 112B of the building 112. The right blocking member 120B blocks the flow of exhaust air discharged from the left side surface (inner surface) of the right heat exchanger 117B toward the front, thereby separating the exhaust path on that side from the intake path on the front. The right blocking member 120B is composed of two members: a front surface member 120Ba extending in the left-right and up-down directions, and an upper surface member 120Bb extending in the left-right and front-rear directions. The front member 120Ba of the right blocking member 120B has a rectangular flat plate shape spanning the vertical height of the right heat exchanger 117B, with its outer end (right end) airtightly connected to the vicinity of the corner between the left side surface (inner surface) and the front of the right heat exchanger 117B and its inner end (left end) airtightly connected to the right side surface (outer surface) of the right side member 112B of the building 112, and extending in a direction approximately perpendicular to the front-to-rear direction (travel direction). The top member 120Bb of the right blocking member 120B has a rectangular flat plate shape spanning the length of the right heat exchanger 117B in the front-to-rear direction, with its outer end (right end) airtightly connected to the vicinity of the corner between the left side surface (inner surface) and the top surface of the right heat exchanger 117B and its inner end (left end) airtightly connected to the right side surface (outer surface) of the right side member 112B of the building 112, and extending in a direction approximately perpendicular to the vertical direction. The upper end of the front surface member 120Ba and the front end of the top surface member 120Bb are airtightly connected (see FIG. 4B).

[0031] The above-described right blocking member 120B prevents outside air (exhaust air) discharged from the left side surface (inner surface) of the right heat exchanger 117B from returning to the front surface via the space outside the side surface and being sucked in again (re-intake).The outside air (exhaust air) is discharged (guided) only downward from the left side surface (inner surface) of the right heat exchanger 117B, passing between the right heat exchanger 117B and the right side surface member 112B of the building 112 and between the right fender 113B and the right blocking member 120B, and therefore heat exchange efficiency can be maintained (see FIGS. 3, 4B, and 5B).

[0032] That is, in the right heat exchanger 117B, in order to prevent the exhaust air from colliding with the frame body 109 that is positioned above and protrudes forward, the upper surface member 120Bb of the right blocking member 120B blocks the exhaust path through which the exhaust air from the inner surface is discharged upward, compared to the left heat exchanger 117A.

[0033] The temperature regulation circuit 127, which is configured by the aforementioned coolant tank 114, left heat exchanger 117A, right heat exchanger 117B, etc. and regulates the temperature of the drive devices and accessories such as the power storage device 110 and DC / DC converter 111, will now be described.

[0034] 6 is a diagram showing the configuration of a temperature control circuit 127 mounted on the dump truck 100. In the figure, solid arrows indicate the flow of coolant, double arrows indicate the flow of refrigerant gas, and dotted arrows indicate information or control commands.

[0035] The temperature control circuit 127 has multiple systems of temperature control circuits that differ depending on the required performance, and has two systems of temperature control circuits: an active temperature control circuit 128 that mainly controls the temperature (cooling) of the storage device 110 of the dump truck 100, and a passive temperature control circuit 129 that controls the temperature (cooling) of driving devices other than the storage device 110 of the dump truck 100, such as the DC / DC converter 111.

[0036] The passive temperature control circuit 129 is a temperature control circuit that uses outside air to cool the coolant. Therefore, the controlled temperature of the coolant is higher than that of the outside air. The passive temperature control circuit 129 is composed of the passive tank 116, pumps 123 to 125 attached to the passive tank 116, a left passive heat exchanger 119A of the left heat exchanger 117A, a right passive heat exchanger 119B of the right heat exchanger 117B, and a passive heat exchanger control device 126 that controls the operation of the left passive heat exchanger 119A and the right passive heat exchanger 119B.

[0037] The passive temperature control circuit 129 stores coolant as a heat medium in a passive tank 116, and pumps 123-125 pump the coolant from the passive tank 116 to the devices to be cooled, namely, the brake device 103, the hydraulic pump motor 106, and the DC / DC converter 111, to cool the devices. The warm liquid after cooling the devices returns to the passive tank 116. To maintain the temperature of the coolant in the passive tank 116 at or below a controlled temperature, the passive temperature control circuit 129 pumps the coolant from the passive tank 116 to the left passive heat exchanger 119A and the right passive heat exchanger 119B. Condenser fans (two in each passive heat exchanger in the illustrated example, hereinafter sometimes simply referred to as fans) are built into the left passive heat exchanger 119A and the right passive heat exchanger 119B, and outside air is drawn in and exhausted by the rotation of the fans. The coolant exchanges heat with the outside air in the left passive heat exchanger 119A and the right passive heat exchanger 119B, cooling the coolant and returning it to the passive tank 116.

[0038] The active temperature control circuit 128 is a temperature control circuit that pressurizes (compresses) the coolant, cools it, and then cools the liquefied refrigerant gas using the heat of vaporization when it expands. Therefore, the controlled temperature of the coolant can be set lower than the outside air temperature. It is also possible to raise the temperature using a heater. The active temperature control circuit 128 is made up of the active tank 115, a pump 121 attached to the active tank 115, heaters 130A to 130C, a left active heat exchanger 118A of the left heat exchanger 117A, a right active heat exchanger 118B of the right heat exchanger 117B, and an active heat exchanger control device 122 that controls the operation of the left active heat exchanger 118A and the right active heat exchanger 118B.

[0039] The active temperature control circuit 128 stores coolant as a heat medium in an active tank 115, and uses a pump 121 to send the coolant from the active tank 115 to the power storage device 110 to be cooled, thereby cooling the power storage device 110. The warm liquid after cooling the power storage device 110 returns to the active tank 115. In order to maintain the temperature of the coolant in the active tank 115 at or below a control temperature, the active temperature control circuit 128 sends the coolant from the active tank 115 to the left active heat exchanger 118A and the right active heat exchanger 118B. A compressor, a condenser, a liquid tank, and an evaporator are built in the left active heat exchanger 118A and the right active heat exchanger 118B, and refrigerant gas circulates in the left active heat exchanger 118A and the right active heat exchanger 118B. In the left active heat exchanger 118A and the right active heat exchanger 118B, this refrigerant gas is compressed → cooled → liquefied → expanded, and the heat absorbed by evaporation during expansion is used to cool the coolant and return it to the active tank 115.

[0040] Furthermore, when the temperature of the coolant is lower than the control temperature, the temperature is increased by heaters 130A to 130C arranged in active tank 115. The number of heaters can be changed as appropriate depending on the required performance or required output.

[0041] The passive heat exchanger control device 126 and the active heat exchanger control device 122 include a processor and a memory, and the processor executes a program stored in the memory to realize the functions of the passive temperature control circuit 129 and the active temperature control circuit 128 of the temperature control circuit 127. The passive heat exchanger control device 126 and the active heat exchanger control device 122 control the operation of the pumps 123 to 125 and the pump 121, respectively, and also control the operation of the left passive heat exchanger 119A, the right passive heat exchanger 119B, the left active heat exchanger 118A, and the right active heat exchanger 118B, respectively. In this way, the passive heat exchanger control device 126 and the active heat exchanger control device 122 control the flow of coolant in the passive temperature control circuit 129 and the active temperature control circuit 128, and adjust the temperatures of the drive devices and accessories, such as the power storage device 110 and the DC / DC converter 111, of the dump truck 100, within an allowable range.

[0042] The passive temperature control circuit 129 is provided with a temperature measuring device that measures the temperature of the coolant in the passive tank 116, and a temperature measuring device that measures the temperature of the coolant before and after heat exchange in the left passive heat exchanger 119A and the right passive heat exchanger 119B, and the measurement results of each temperature measuring device are transmitted to the passive heat exchanger control device 126.

[0043] The passive heat exchanger control device 126 controls the operation of the pumps 123 to 125, calculates the required cooling output (hereinafter sometimes simply referred to as the required output) from the temperature of the coolant in the passive tank 116, and calculates the heat exchange efficiency from the temperatures of the coolant before and after heat exchange in the left passive heat exchanger 119A and the right passive heat exchanger 119B. Based on the calculated required output and the heat exchange efficiencies of the left passive heat exchanger 119A and the right passive heat exchanger 119B, the passive heat exchanger control device 126 calculates the output distribution to the left passive heat exchanger 119A and the right passive heat exchanger 119B to meet the required output, and transmits a control command to supply power to the left passive heat exchanger 119A and the right passive heat exchanger 119B according to the output distribution. The passive heat exchanger control device 126 can also calculate the power distribution to each fan in the left passive heat exchanger 119A and the right passive heat exchanger 119B to satisfy the required power output, and send a control command to supply power to each fan according to the power distribution. In this way, the passive heat exchanger control device 126 controls the flow or temperature of the coolant in the passive temperature control circuit 129.

[0044] The active temperature control circuit 128 is provided with a temperature measuring device that measures the temperature of the coolant in the active tank 115, and a temperature measuring device that measures the temperature of the coolant before and after heat exchange in the left active heat exchanger 118A and the right active heat exchanger 118B, and the measurement results of each temperature measuring device are transmitted to the active heat exchanger control device 122.

[0045] The active heat exchanger control device 122 controls the operation of the pump 121 and the heaters 130A to 130C, calculates the required cooling output (required output) from the temperature of the coolant in the active tank 115, and calculates the heat exchange efficiency from the temperatures of the coolant before and after heat exchange in the left active heat exchanger 118A and the right active heat exchanger 118B. The active heat exchanger control device 122 calculates the output distribution to the left active heat exchanger 118A and the right active heat exchanger 118B to meet the required output from the calculated required output and the heat exchange efficiencies of the left active heat exchanger 118A and the right active heat exchanger 118B, and transmits a control command to supply power to the left active heat exchanger 118A and the right active heat exchanger 118B according to the output distribution. The active heat exchanger control device 122 can also calculate the power distribution to each of the heaters 130A to 130C in the active tank 115 to satisfy the required power, and send a control command to supply power to each of the heaters 130A to 130C according to the power distribution. In this way, the active heat exchanger control device 122 controls the flow or temperature of the coolant in the active temperature adjustment circuit 128.

[0046] As described above, the passive temperature control circuit 129 and the active temperature control circuit 128 of the temperature control circuit 127 are equipped with two passive heat exchangers and two active heat exchangers, one for each heat exchanger provided on the left and right sides of the dump truck 100. As shown in Fig. 7, when a device malfunctions and the required output is not achieved, the passive heat exchanger control device 126 and the active heat exchanger control device 122 are capable of performing performance complement control, in which the output of the normal device is increased (compared to the output when both devices are normal) to compensate for the performance of the malfunctioning device.

[0047] In addition, as shown in Figure 8, the passive heat exchanger control device 126 and the active heat exchanger control device 122 can temporarily output (calculate) an output that exceeds 100% of the rated output within the range acceptable to the equipment (for example, 150%), thereby meeting the required output.

[0048] Furthermore, as shown in FIG. 9, when one of the multiple fans in the passive heat exchanger malfunctions and the required output is not achieved, the passive heat exchanger control device 126 can perform performance complementation control, in which the output of the normal fans is increased (compared to the output of each fan when it is normal) to compensate for the performance of the malfunctioning fan.

[0049] Furthermore, as shown in FIG. 10, when one of the heaters in the active tank malfunctions and the required output is not achieved, the active heat exchanger control device 122 can perform performance complementation control, in which the output of the normal heaters is increased (compared to the output of each heater when it is normal) to compensate for the performance of the malfunctioning heater.

[0050] As explained above, if the heat exchanger is placed on the front of the fender and exhaust is discharged from the side of the heat exchanger, there is nothing obstructing the exhaust path to the outside of the vehicle, but there is a vehicle structure (building) on ​​the inside of the vehicle, and the exhaust hits the vehicle structure in the center of the vehicle, causing the exhaust pressure to rise between the side of the heat exchanger and the side of the vehicle structure.The pressurized exhaust then flows to the front of the heat exchanger, which is at low pressure, and is drawn in from the intake surface on the front of the heat exchanger, reducing heat exchange efficiency.

[0051] In the dump truck 100 of this embodiment, blocking members (left blocking member 120A, right blocking member 120B) are provided at positions between the front and side surfaces outside the heat exchangers (left heat exchanger 117A, right heat exchanger 117B) to block the flow of exhaust gas discharged from the side surfaces toward the front surfaces. More specifically, the blocking members (left blocking member 120A, right blocking member 120B) that suppress circulation are disposed between the side surfaces of the heat exchangers on the vehicle structure side (vehicle center side) and the side surfaces of the vehicle structure facing (opposing) the side surfaces. This prevents a decrease in heat exchange efficiency and maintains heat exchange efficiency, thereby suppressing output limitations when the equipment to be cooled is at high temperatures.

[0052] Furthermore, in a vehicle equipped with multiple heat exchangers, when some of the devices malfunction, the heat exchange performance decreases.

[0053] In the dump truck 100 of this embodiment, the output of normal equipment is increased to compensate for the performance degradation (insufficient output) of malfunctioning equipment. Furthermore, the upper output limit of normal equipment is temporarily increased (to exceed 100% of the rated output) to compensate for the performance degradation (output reduction) of malfunctioning equipment. In other words, multiple devices with the same cooling and heating functions are installed in the temperature control circuit, and a measuring device capable of monitoring the status of each device is attached. The heat exchange efficiency of each device is calculated, and the drive output allocation is determined based on the heat exchange efficiency of each device to satisfy the required output. This suppresses the decrease in heat exchange efficiency and the decrease in vehicle running and driving performance, thereby maintaining the availability rate, braking performance, and preventing immobility.

[0054] In the above embodiment, two heat exchangers (left heat exchanger 117A and right heat exchanger 117B) are used, separated and arranged on the left and right sides of the power source, such as the power storage device 110, as the heat exchangers for adjusting the temperature of the heat medium (coolant) for adjusting the temperature of the drive unit. However, three or more heat exchangers having a built-in temperature control circuit and cooling and heating functions may be separated and arranged in appropriate positions. In addition, the shape and arrangement of the shutoff members (left shutoff member 120A and right shutoff member 120B) that suppress circulation may be changed as appropriate.

[0055] Although the above embodiment is an electrically powered vehicle equipped with a power storage device as a power source, an engine may be provided as a power source instead of or in addition to the power storage device. The above embodiment may also be applied to earthmoving machines or construction machines other than dump trucks.

[0056] Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above embodiments and various modifications can be made without departing from the spirit of the present invention. In the present invention, the configuration of one embodiment can be added to the configuration of another embodiment, the configuration of one embodiment can be replaced with the configuration of another embodiment, or part of the configuration of one embodiment can be deleted. [Explanation of symbols]

[0057] 100...dump truck, 101...front wheel (wheel), 102...rear wheel (wheel), 103...braking device, 104...body frame, 105...bed, 106...hydraulic pump motor, 110...electricity storage device, 111...DC / DC converter, 112...building (supporting member), 113A...left fender, 113B...right fender, 114...coolant tank, 115...active tank, 116...passive tank, 117A...left heat exchanger, 117 B...right heat exchanger, 118A...left active heat exchanger, 118B...right active heat exchanger, 119A...left passive heat exchanger, 119B...right passive heat exchanger, 120A...left blocking member, 120B...right blocking member, 120Ba...front member, 120Bb...top member, 122...active heat exchanger control device, 126...passive heat exchanger control device, 127...temperature control circuit, 128...active temperature control circuit, 129...passive temperature control circuit

Claims

1. a body having wheels; a drive unit including a power source for operating the vehicle body; a fender covering the wheel; A dump truck equipped with a heat exchanger that is provided on the front surface of the fender, that takes in outside air from the front surface and discharges it from the side, and that adjusts the temperature of a heat medium for adjusting the temperature of the drive unit, A dump truck characterized in that a blocking member is provided at a position outside the heat exchanger between the front surface and the side surface to block the flow of exhaust gas discharged from the side surface toward the front surface.

2. The dump truck according to claim 1, a support member having the power source supported on one side thereof and the fender provided on the other side thereof; the heat exchanger is provided on a front surface of the fender at a distance from the other side surface of the support member, The dump truck is characterized in that the blocking member extends between the heat exchanger and the support member.

3. The dump truck according to claim 1, The dump truck is characterized in that the blocking member is configured to guide exhaust gas discharged from the side surface of the heat exchanger in an upward and downward direction.

4. The dump truck according to claim 3, The dump truck is characterized in that the blocking member is configured as a member extending in a direction perpendicular to the traveling direction.

5. The dump truck according to claim 1, The dump truck is characterized in that the blocking member is configured to guide exhaust gas discharged from the side surface of the heat exchanger only downward.

6. The dump truck according to claim 5, The dump truck is characterized in that the blocking member is composed of a front member extending in a direction perpendicular to the traveling direction and an upper member extending in a direction perpendicular to the up-down direction.

7. The dump truck according to claim 1, The dump truck is characterized in that the heat exchanger is arranged in a plurality of divided parts on either side of the power source.

8. The dump truck according to claim 7, a temperature measuring device for measuring the temperature of the heat medium before and after heat exchange in each heat exchanger; a heat exchanger control device that calculates the heat exchange efficiency of each heat exchanger from the temperature of the heat medium before and after heat exchange in each of the heat exchangers, and calculates an output allocation to each heat exchanger to satisfy the required output from the required outputs of the plurality of heat exchangers and the heat exchange efficiencies of each of the heat exchangers.

9. The dump truck according to claim 8, The dump truck is characterized in that the heat exchanger control device is capable of temporarily calculating an output distribution that exceeds 100% of the rated output of each heat exchanger.

10. The dump truck according to claim 1, The dump truck is characterized in that the power source is an electric storage device.

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