Patent Publication Number: US-2018050727-A1

Title: Working vehicle

Description:
FIELD 
     The present invention relates to a working vehicle. 
     BACKGROUND 
     In a working vehicle, a variety of fluids such as fuel, oil, and cooling water are used. A remaining amount of the fluid is checked in an inspection of the working vehicle. In order to check the remaining amount of the fluid, it is often the case that a gauge is provided in a housing member in which the fluid is housed. An inspector checks the remaining amount of the fluid by observing the gauge. For example, in a pre-operation inspection of the working vehicle, the inspector checks a remaining amount of cooling water in a radiator by observing a gauge provided in the radiator. 
     CITATION LIST 
     Patent Literature 
     Patent Literature 1: JP 2015-190259 A 
     SUMMARY 
     Technical Problem 
     When a working vehicle is in a stopped state on an inclined ground surface, even though a housing member for fluid, such as a tank, inclines, a liquid level of the fluid is parallel to a horizontal plane. Therefore, when the working vehicle is in the stopped state on the inclined ground surface, a gauge provided in the housing member may not be able to correctly indicate a remaining amount of the fluid. For example, when the working vehicle is a large dump truck that operates in a mining site of a mine, a housing member for fluid provided in the dump truck is also large. When the housing member is large, a position of an end portion of the housing member changes greatly even when an inclination of the ground surface is slight. Therefore, when the gauge is provided at the end portion of the housing member, there is a high possibility that the gauge is not able to correctly indicate a remaining amount of the fluid. 
     An aspect of the present invention has an object to provide a working vehicle that can correctly indicate a remaining amount of fluid. 
     Solution to Problem 
     According to an aspect of the present invention, a working vehicle comprises: a housing member in which fluid is housed; and a gauge that indicates a remaining amount of the fluid in the housing member, wherein the gauge is disposed at a central portion of the housing member in a longitudinal direction. 
     Advantageous Effects of Invention 
     According to an aspect of the present invention, a working vehicle that can correctly indicate a remaining amount of fluid is provided. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a perspective view illustrating an example of a working vehicle according to the present embodiment. 
         FIG. 2  is a schematic view of the working vehicle according to the present embodiment as viewed from the front. 
         FIG. 3  is a schematic view of a portion of the working vehicle according to the present embodiment as viewed from a left side. 
         FIG. 4  is a schematic view of a portion of an upper tank according to the present embodiment as viewed from behind. 
         FIG. 5  is a schematic view of a portion of the upper tank according to the present embodiment as viewed from above. 
         FIG. 6  is a view of portions of a floor deck, a cover member, and a handrail according to the present embodiment as viewed from above. 
         FIG. 7  is a view illustrating a state in which a first lid is removed from a base member of the cover member according to the present embodiment. 
         FIG. 8  is a view illustrating a state in which the first lid, a second lid, and a nonslip plate are removed from the base member of the cover member according to the present embodiment. 
         FIG. 9  is a schematic view illustrating a state in which a driver is observing a level gauge through an opening portion in a pre-operation inspection according to the present embodiment. 
         FIG. 10  is a view illustrating action of a radiator according to a comparative example. 
         FIG. 11  is a view illustrating action of the radiator according to the present embodiment. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     In the following, an embodiment according to the present invention will be described with reference to the drawings. However, the present invention is not limited to this embodiment. The components of the embodiment described below can optionally be combined. Furthermore, there may be a case where some of the components are not used. 
     In the following description, a positional relationship among respective portions will be described using the terms “vertical direction”, “left-right direction”, and “front-rear direction”. The vertical direction refers to a direction perpendicular to a ground contact surface of a wheel of a working vehicle which is in contact with the ground surface. The left-right direction refers to a direction parallel to a rotation axis of a wheel which is not steered among a plurality of wheels of the working vehicle. In addition, the left-right direction is synonymous with a vehicle width direction of the working vehicle. The front-rear direction refers to a direction perpendicular to the left-right direction and the vertical direction. 
     An upper side refers to one direction in the vertical direction, and the direction separating from the ground contact surface of the wheel. A lower side refers to a direction opposite to the upper side in the vertical direction, and the direction approaching the ground contact surface of the wheel. A left side refers to one direction in the left-right direction, and the direction in a left side based on a driver seated on a seat of the working vehicle when the seat on which the driver of the working vehicle sits and a steering wheel operated by the driver are provided. A right side refers to a direction opposite to the left side in the left-right direction, and the direction in a right side based on the driver seated on the seat of the working vehicle. A front side refers to one direction in the front-rear direction, and the direction from the seat toward the steering wheel. A rear side refers to a direction opposite to the front side in the front-rear direction, and the direction from the steering wheel toward the seat. 
     Moreover, an upper portion refers to a portion at an upper side of a member or space in the vertical direction, and the portion separated from the ground contact surface of the wheel. A lower portion refers to a portion at a lower side of the member or the space in the vertical direction, and the portion close to the ground contact surface of the wheel. A left portion refers to a portion at a left side of the member or the space based on the driver seated on the seat of the working vehicle. A right portion refers to a portion at a right side of the member or the space based on the driver seated on the seat of the working vehicle. A front portion refers to a portion at a front side of the member or the space in the front-rear direction. A rear portion refers to a portion at a rear side of the member or the space in the front-rear direction. 
     [Working Vehicle] 
       FIG. 1  is a perspective view illustrating an example of a working vehicle  1  according to the present embodiment. 
     In the present embodiment, an example in which a dump truck  1  is the working vehicle  1  will be described. The dump truck  1  is a self-propelled off-road dump truck that operates in a mining site of a mine. The dump truck  1  is a rigid-frame type. Note that, the dump truck  1  may be an articulate type. 
     As illustrated in  FIG. 1 , the dump truck  1  includes a vehicle main body  2 , a dump body  3  supported by the vehicle main body  2  and on which a cargo is loaded, and a traveling device  4  that supports the vehicle main body  2  and is movable. 
     The vehicle main body  2  has a frame  21 , a floor deck  22  provided at an upper portion of the frame  21 , and a lower deck  23  provided at a lower portion of the frame  21 . The frame  21  supports the traveling device  4 . 
     A movable ladder  5  is provided on the lower deck  23 . An inclined ladder  6  is provided between the lower deck  23  and the floor deck  22 . A lower end portion of the inclined ladder  6  is connected to a left portion of the lower deck  23 , and an upper end portion of the inclined ladder  6  is connected to a right portion of the floor deck  22 . A handrail  7  is provided in front of the floor deck  22 . 
     The vehicle main body  2  has an operating room  8 . The operating room  8  is disposed at least on a portion of the floor deck  22 . In the present embodiment, the operating room  8  is provided on a left portion of the floor deck  22 . At least a portion of the floor deck  22  is disposed in front of the operating room  8 . In addition, at least a portion of the floor deck  22  is disposed on a right side of the operating room  8 . 
     A driver boards on the operating room  8 . A seat on which the driver sits is provided in the operating room  8 . Furthermore, a plurality of operation devices disposed in the operating room  8  is operated by the driver. The operation devices disposed in the operating room  8  include at least a steering wheel. As described above, the front side refers to the direction from the seat toward the steering wheel. The driver adjusts a traveling direction of the dump truck  1  by operating the steering wheel. 
     When the driver boards on the operating room  8 , the driver, after climbing the movable ladder  5  at a left portion of the vehicle main body  2  and moving to the lower deck  23 , climbs the inclined ladder  6  and moves to the right portion of the floor deck  22 . Then, the driver who has arrived at the right portion of the floor deck  22  walks toward the left portion of the floor deck  22 . Thereafter, the driver who has arrived at the left portion of the floor deck  22  moves to a left portion of the operating room  8 , opens a door provided at the left portion of the operating room  8 , and boards on the operating room  8 . The floor deck  22  is a portion of a path for the driver or an inspector to access to the operating room  8 . 
     The cargo is loaded on the dump body  3 . The dump body  3  can stand or sit by an actuator such as a hydraulic cylinder. The actuator is disposed between the vehicle main body  2  and the dump body  3 , and can cause the dump body  3  to stand or sit. The dump body  3  is adjusted by the actuation of the actuator so as to take a loading posture and/or a standing posture. The loading posture refers to a posture in which the dump body  3  is, within a movable range of the dump body  3 , lowered to the most to be at the closest to the vehicle main body  2  and seated. The standing posture refers to a posture in which the dump body  3  is, within the movable range of the dump body  3 , raised to the most to be at the farthest from the vehicle main body  2 . When the dump body  3  is in the loading posture, the cargo is loaded on the dump body  3  and the dump truck  1  can travel. When the dump body  3  is in the standing posture, the cargo is discharged from the dump body  3 . 
     In the present embodiment, the dump truck  1  is a rear-dumping type, and the cargo is discharged from the dump body  3  by inclining the dump body  3  to the rear side. Note that, the dump truck  1  may be a side-dumping type that discharges the cargo from the dump body  3  by inclining the dump body  3  to the left side or the right side. 
     The dump body  3  has a protector  31 . The protector  31  is a flange portion disposed at a front portion of the dump body  3 . In the loading posture, the protector  31  of the dump body  3  is disposed above the operating room  8 . Moreover, in the loading posture, the protector  31  of the dump body  3  is disposed above a portion of the floor deck  22 . 
     The traveling device  4  includes front wheels  41  and rear wheels  42 . The rear wheels  42  are disposed behind the front wheels  41 . The front wheels  41  are each disposed at a left side and a right side of the vehicle main body  2 . The rear wheels  42  are each disposed at the left side and the right side of the vehicle main body  2 . The rear wheels  42  at the left side and right side each include two tires. 
     That is, the dump truck  1  according to the present embodiment is a four-wheel vehicle, and the number of tires used is two in the front wheels  41  and four in the rear wheels  42 . 
     The traveling device  4  is actuated by power generated by a power generation device provided in the vehicle main body  2 . The power generation device includes an internal combustion engine such as a diesel engine, and/or an electric motor. 
     The front wheel  41  rotates about a rotation axis. The rear wheel  42  rotates about a rotation axis. The rear wheel  42  rotates and the traveling device  4  travels by the power generated by the power generation device. The front wheels  41  are steered by the operation of the steering wheel by the driver. In the present embodiment, the rear wheels  42  are not steered by the operation of the steering wheel. As described above, the left-right direction refers to the direction parallel to the rotation axis of the wheel which is not steered among the plurality of wheels of the working vehicle  1 . In the present embodiment, the left-right direction refers to a direction parallel to the rotation axis of the rear wheel  42 . 
     [Radiator] 
       FIG. 2  is a schematic view of the dump truck  1  according to the present embodiment as viewed from the front. In  FIG. 2 , the structure of the dump truck  1  illustrated in  FIG. 1  is partially omitted.  FIG. 3  is a schematic view of a portion of the dump truck  1  according to the present embodiment as viewed from the left side. As illustrated in  FIGS. 1, 2 and 3 , the dump truck  1  has a radiator  10 . The radiator  10  is a housing member in which cooling water (coolant), which is fluid, is housed. The cooling water is liquid. The radiator  10  is disposed at a front portion of the vehicle main body  2 . 
     In the vertical direction, the radiator  10  is disposed between the lower deck  23  and the upper deck  22 . In the left-right direction, the radiator  10  is disposed at a central portion of the vehicle main body  2 . 
     As illustrated in  FIGS. 2 and 3 , a dimension of the radiator  10  in the left-right direction is longer than a dimension of the radiator  10  in the front-rear direction. In the following description, the left-right direction of the radiator  10  is appropriately referred to as a longitudinal direction of the radiator  10 . 
     In the present embodiment, an outer shape of the radiator  10  and a shape of a housing space of the radiator  10  in which the cooling water is housed are substantially similar to each other. The housing space of the radiator  10  is an internal space of the radiator  10  in which the cooling water is housed. As described later, the radiator  10  has an upper tank  11 , a core tank  12 , and a lower tank  13 . The housing space of the radiator  10  includes an internal space of the upper tank  11  in which the cooling water is stored, an internal space of the core tank  12 , and an internal space of the lower tank  13 . When the outer shape of the radiator  10  is a rectangular shape, the housing space of the radiator  10  is also a rectangular shape. The dimension of the radiator  10  includes a dimension of the housing space of the radiator  10  in which the cooling water is housed. The longitudinal direction of the radiator  10  and the longitudinal direction of the housing space of the radiator  10  are the same. 
     A central portion of the radiator  10  in the longitudinal direction refers to a portion in a central portion of the housing space divided into D equal portions when the housing space of the radiator  10  in which the cooling water is housed is divided into D equal portions in the longitudinal direction. 
     The radiator  10  has the upper tank  11 , the core tank  12 , and the lower tank  13 . A radiator core is disposed in the core tank  12 . The upper tank  11  has a supply port  14  for supplying the cooling water to the radiator  10 . A predetermined amount of the cooling water is stored in the internal space of the upper tank  11 . The cooling water is supplied to the radiator  10  through the supply port  14 . The supply port  14  is closed by a cap  15 . 
     The supply port  14  is provided in a central portion of the upper tank  11  in the longitudinal direction. 
     [Gauge] 
     Next, a gauge  50  according to the present embodiment will be described using  FIGS. 2, 3, 4, and 5 .  FIG. 4  is a schematic view of a portion of the upper tank  11  according to the present embodiment as viewed from behind.  FIG. 5  is a schematic view of a portion of the upper tank  11  according to the present embodiment as viewed from above. 
     As illustrated in  FIGS. 2, 3, 4, and 5 , the dump truck  1  includes the gauge  50  that indicates a remaining amount of the cooling water in the radiator  10 . The gauge  50  is a so-called level gauge. In the following description, the gauge  50  is appropriately referred to as a level gauge  50 . 
     The level gauge  50  is connected to an upper portion of the radiator  10 . As illustrated in  FIG. 2 , in the present embodiment, the level gauge  50  is disposed at the central portion of the radiator  10  in the longitudinal direction. As described above, in the present embodiment, the housing space of the radiator  10  is substantially a rectangular shape. The central portion of the radiator  10  in the longitudinal direction refers to the central portion in an upper portion of the housing space of the radiator  10  in the longitudinal direction. 
     The upper tank  11  has an upper surface  11 A facing up, and a rear surface  11 B facing down. The level gauge  50  is connected to the rear surface  11 B of the upper tank  11 . 
     The level gauge  50  is a long rod-shaped member and has a central axis AX. As illustrated in  FIG. 5 , the level gauge  50  is connected to the rear surface  11 B of the upper tank  11  through a connecting member  60 . The connecting member  60  has a base portion  63 , a first holding portion  61 , and a second holding portion  62 . The base portion  63  is connected to the rear surface  11 B of the upper tank  11 . The first holding portion  61  is connected to the base portion  63  and holds one end portion of the level gauge  50 . The second holding portion  62  is connected to the base portion  63  and holds the other end portion of the level gauge  50 . A gap is formed between the base portion  63  and the level gauge  50 . 
     As illustrated in  FIG. 4 , the level gauge  50  inclines to the upper surface  11 A of the upper tank  11  in the upper tank  11  provided in the upper portion of the radiator  10 . That is, the level gauge  50  is provided in the upper tank  11  so that the central axis AX of the level gauge  50  inclines to a virtual vertical axis extending in the vertical direction and to a virtual left-right axis extending in the left-right direction. 
     In the present embodiment, the level gauge  50  is provided in the upper tank  11  so that the central axis AX of the level gauge  50  is perpendicular to a virtual front-rear axis extending in the front-rear direction. In other words, the central axis AX of the level gauge  50  is disposed in parallel with a predetermined plane including the vertical axis and the left-right axis. The level gauge  50  is provided in the upper tank  11  so that the central axis AX inclines to a horizontal plane in the predetermined plane. In the present embodiment, an angle θ formed by the horizontal plane and the central axis AX is 30[°] to 45[°]. 
     As illustrated in  FIG. 3 , the radiator  10  is disposed in front of the floor deck  22 . The level gauge  50  is disposed so as to be adjacent to the floor deck  20 . The level gauge  50  is disposed between the handrail  7  and the floor deck  22  in the front-rear direction. 
     In the upper surface  11 A of the upper tank  11 , the supply port  14  is provided in the central portion of the radiator  10  in the longitudinal direction. In the rear surface  112  of the upper tank  11 , the level gauge  50  is provided in the central portion of the radiator  10  in the longitudinal direction. The level gauge  50  is disposed so as to be adjacent to the supply port  14 . 
     Furthermore, when the dump body  3  is in the loading posture, the level gauge  50  is disposed in front of the protector  31  of the dump body  3 . The level gauge  50  is disposed at least in front of a front end portion  31 E of the protector  31 . 
     As illustrated in  FIG. 3 , in the present embodiment, the dump truck  1  includes a cover member  70  disposed at least on a portion of a periphery of the radiator  10 . The cover member  70  protects the radiator  10 . 
     In addition, the cover member  70  protects the level gauge  50 . In the present embodiment, at least a portion of the cover member  70  faces the upper surface  11 A of the upper tank  11 . Moreover, at least a portion of the cover member  70  faces the rear surface  11 B of the upper tank  11 . 
     An opening portion  71  is provided in a portion of the cover member  70 . At least a portion of the level gauge  50  is disposed at an inner side of the opening portion  71 . 
     The internal space of the upper tank  11  and the internal space of the level gauge  50  are connected to each other through a flow path (not illustrated) provided inside the connecting member  60 . As illustrated in  FIG. 3 , the heights of a liquid level of the cooling water stored in the internal space of the upper tank  11  and a liquid level of the cooling water in the internal space of the level gauge  50  in the vertical direction are maintained at the same height. That is, the liquid level of the cooling water stored in the internal space of the upper tank  11  and the liquid level of the cooling water in the internal space of the level gauge  50  are disposed in the same plane. The inspector can observe the level gauge  50  through the opening portion  71 . The inspector can check the remaining amount of the cooling water in the radiator  10  by observing the level gauge  50 . Note that, the inspector and the driver may be the same person, or the inspector and the driver may be different. 
       FIGS. 6, 7, and 8  are specific examples illustrating a portion of the dump truck  1  according to the present embodiment. 
       FIG. 6  is a view of portions of the floor deck  22 , the cover member  70 , and the handrail  7  according to the present embodiment as viewed from above. As illustrated in  FIG. 6 , the cover member  70  is disposed in front of the floor deck  22 . The opening portion  71  is provided in the portion of the cover member  70 . At least the portion of the level gauge  50  is disposed at the inner side of the opening portion  71 . Therefore, the inspector of the floor deck  22  can visually check the level gauge  50  through the opening portion  71 . 
     Moreover, the handrail  7  is provided in front of the floor deck  22 . The handrail  7  is, for example, supported by the cover member  70 . The level gauge  50  is disposed in front of the floor deck  22 , and is adjacent to a front end portion of the floor deck  22 . The level gauge  50  is disposed between the handrail  7  and the floor deck  22  in the front-rear direction. 
     In the present embodiment, the floor deck  22  includes a nonslip plate  24 . The nonslip plate  24  has an upper surface, and a plurality of recessed portions or openings provided in the upper surface. The nonslip plate  24  has the plurality of recessed portions or openings in the upper surface, thereby suppressing slipping of the inspector who walks on the upper surface of the nonslip plate  24 . 
     The level gauge  50  is adjacent to a front end portion of the nonslip plate  24 . Therefore, when the inspector observes the level gauge  50  through the opening portion  71  or supplies the cooling water from the supply port  14  to the radiator  10 , as described later, the inspector can inspect the remaining amount of the cooling water or supply the cooling water, respectively, without slipping. In addition, the handrail  7  is provided in front of the nonslip plate  24  and the level gauge  50 . Therefore, accidental falling of the inspector, who is visually checking the level gauge  50  or supplying the cooling water, is suppressed. 
     The cover member  70  has a base member  708 , a first lid  72 , and a second lid  73 . The first lid  72  is provided on a portion of the base member  70 B, and closes a first opening  72 K. The second lid  73  is provided on a portion of the base member  70 B, and closes a second opening  73 K. In the present embodiment, the opening portion  71  is provided in the first lid  72 . 
       FIG. 7  is a view illustrating a state in which the first lid  72  is removed from the base member  70 B of the cover member  70  according to the present embodiment. As illustrated in  FIGS. 6 and 7 , the first opening  72 K is long in the left-right direction. By removing the first lid  72  from the first opening  72 K, the inspector can sufficiently observe or inspect not only the level gauge  50  but also the upper tank  11 . 
       FIG. 8  is a view illustrating a state in which the first lid  72 , the second lid  73 , and the nonslip plate  24  are removed from the base member  70 B of the cover member  70  according to the present embodiment. As illustrated in  FIG. 8 , the cap  15  is disposed in the second opening  73 K. The cap  15  appears when the second lid  73  is removed from the second opening  73 K. By removing the second lid  72  and the cap  15 , the inspector can supply the cooling water from the supply port  14  to the radiator  10 . 
     When only the supplying of the cooling water is performed, the inspector removes the second lid  73 , but does not need to remove the first lid  72  and the nonslip plate  24 . In other words, the supplying of the cooling water can be performed by removing only a minimum member (lid) and thus, no load, such as the removal of a large and heavy member, is given to the inspector. When the inspector determines that the remaining amount of the cooling water is small by observing the level gauge  50  through the opening portion  71 , the inspector can supply the cooling water from the supply port  14  to the radiator  10  by removing the second lid  73  and removing the cap  15 . 
     After the supplying of the cooling water is completed, the cap  15  and the second lid  73  are mounted by the inspector. 
     [Inspection Method] 
     Next, a method for inspecting the remaining amount of the cooling water according to the present embodiment will be described. In the present embodiment, there will be described an example in which, in the pre-operation inspection of the dump truck  1 , the driver of the dump truck  1 , who is the inspector, observes the level gauge  50  provided in the radiator  10  to check the remaining amount of the cooling water in the radiator  10 . 
     In order to board on the operating room  8 , the driver, after climbing the movable ladder  5  at the left portion of the vehicle main body  2  and moving to the lower deck  23 , climbs the inclined ladder  6 . Accordingly, the driver arrives at the right portion of the floor deck  22 . 
     Then, the driver who has arrived at the right portion of the floor deck  22  walks toward the left portion of the floor deck  22 . The opening portion  71  is provided in a walking path of the driver. Therefore, before moving to the operating room  8 , the driver on the floor deck  22  can easily and surely observe the level gauge  50  through the opening portion  71 . 
       FIG. 9  is a schematic view illustrating a state in which the driver is observing the level gauge  50  through the opening portion  71  in the pre-operation inspection according to the present embodiment. As illustrated in  FIG. 9 , the driver can observe the level gauge  50  through the opening portion  71 . Through the opening portion  71 , the driver observes the level gauge  50  from above. In the present embodiment, the level gauge  50  includes a direct-viewing type liquid level gauge, and inclines to the upper surface  11 A of the radiator  10  in the upper portion of the radiator  10 . Therefore, even when the driver observes the level gauge  50  from above through the small opening portion  71 , the driver can easily and surely observe the liquid level of the cooling water in the level gauge  50 . 
     In the present embodiment, the nonslip plate  24  is provided on the floor deck  22 . In addition, the handrail  7  is provided in front of the nonslip plate  24 . Therefore, the safety of the foot and the front of the driver who observes the level gauge  50  is ensured. 
     Moreover, the level gauge  50  is disposed in front of the protector  31  of the dump body  3 . The level gauge  50  is disposed at least in front of the front end portion  31 E of the protector  31 . Accordingly, an upper side of the level gauge  50  is opened and thus, sufficiently illuminated with illumination light such as sunlight. Therefore, the driver can sufficiently observe the level gauge  50 . 
     When the inspector determines that the remaining amount of the cooling water is small by observing the level gauge  50  through the opening portion  71 , the inspector can supply the cooling water from the supply port  14  to the radiator  10  by removing the second lid  73  and removing the cap  15 . After the supplying of the cooling water is completed, the cap  15  and the second lid  73  are mounted by the inspector. 
     The driver who has completed the pre-operation inspection walks on the floor deck  22  and boards on the operating room  8 . Then, the operation of the dump truck  1  starts. 
     [Action and Effect] 
     As described above, according to the present embodiment, the level gauge  50  is disposed at the central portion of the radiator  10  in the longitudinal direction. Therefore, in the pre-operation inspection, even when the vehicle is in a stopped state on an inclined ground surface and thus, the radiator  10  inclines to the horizontal plane, the level gauge  50  can correctly indicate the remaining amount of the cooling water. 
       FIG. 10  is a view illustrating action of the radiator  10  according to a comparative example.  FIG. 10  is a schematic diagram illustrating an example in which the level gauge  50  is provided at an end portion of the radiator  10  in the longitudinal direction. 
     When the dump truck  1  is in a stopped state on a horizontal ground surface, the radiator  10  is also installed horizontally as illustrated by a dotted line in  FIG. 10 . In such case, the level gauge  50  can correctly indicate the remaining amount of the cooling water in the radiator  10 . 
     There is a case where the dump truck  1  is in a stopped state on an inclined ground surface. When the dump truck  1  is in the stopped state on the inclined ground surface, the radiator  10  also inclines as illustrated by a solid line in  FIG. 10 . However, even when the radiator  10  inclines, the liquid level of the cooling water is parallel to the horizontal plane. When the radiator  10  is large and a dimension of the radiator  10  in the longitudinal direction is long, a position of the end portion of the radiator  10  in the longitudinal direction changes greatly in the vertical direction even when an inclination of the ground surface is slight. As illustrated in  FIG. 10 , when the level gauge  50  is provided at the end portion of the radiator  10  in the longitudinal direction, there is a high possibility that the level gauge  50  is not able to correctly indicate the remaining amount of the cooling water. In the example illustrated in  FIG. 10 , the level gauge  50  is provided at an end portion on the right side of the radiator  10  in the longitudinal direction, and the level gauge  50  indicates the remaining amount of the cooling water larger than the actual remaining amount. On the other hand, when the level gauge  50  is provided at an end portion on the left side of the radiator  10  in the longitudinal direction, the level gauge  50  indicates the remaining amount of the cooling water smaller than the actual remaining amount. In a large dump truck  1  that operates in a mine, particularly, depending on an attached position of the level gauge  50  in the radiator  10 , the accuracy of a remaining-amount indication of the cooling water is affected by the inclination of the ground surface. 
       FIG. 11  is a view illustrating action of the radiator  10  according to the present embodiment.  FIG. 11  is a schematic diagram illustrating an example in which the level gauge  50  is provided at the central portion of the radiator  10  in the longitudinal direction. When the dump truck  1  is in a stopped state on a horizontal ground surface, the radiator  10  is also installed horizontally as illustrated by a dotted line in  FIG. 11 . In such case, the level gauge  50  can correctly indicate the remaining amount of the cooling water in the radiator  10 . 
     When the dump truck  1  is in a stopped state on an inclined ground surface, the radiator  10  also inclines as illustrated by a solid line in  FIG. 11 . However, even when the radiator  10  inclines, the liquid level of the cooling water is parallel to the horizontal plane. Even though the position of the end portion of the radiator  10  in the longitudinal direction changes greatly in the vertical direction when the radiator  10  inclines, the change of a position of the central portion of the radiator  10  in the longitudinal direction is suppressed. That is, when the level gauge  50  is provided at the central portion of the radiator  10  in the longitudinal direction, the level gauge  50  can correctly indicate the remaining amount of the cooling water. 
     Furthermore, in the present embodiment, the level gauge  50  includes a direct-viewing type liquid level gauge, and is installed so as to incline to the upper surface  11 A of the radiator  10  in the upper portion of the radiator  10 . When the dump truck  1  is in the stopped state on the horizontal ground surface, the upper surface  11 A of the radiator  10  is substantially parallel to the horizontal plane. The level gauge  50  is provided so that the central axis AX of the level gauge  50  inclines; therefore, the visibility of the level gauge  50  improves. As a result, the inspector can easily and surely check the remaining amount of the cooling water by directly observing the level gauge  50  from above. 
     Moreover, in the present embodiment, the level gauge  50  is disposed so as to be adjacent to the floor deck  22 . Accordingly, the inspector can easily observe the level gauge  50  by moving to the floor deck  22 . In addition, the driver boards on the operating room  8  by moving from the movable ladder  5  to the lower deck  23 , the inclined ladder  6 , and the floor deck  22 . Since the level gauge  50  is adjacent to the floor deck  22 , the remaining-amount inspection of the cooling water is incorporated in a pre-operation movement process, that is, in the middle of the access path to the operating room  8 , of the driver. The driver can easily and surely observe, without forgetting, the level gauge  50 , and check the remaining amount of the cooling water. 
     Furthermore, in the present embodiment, the level gauge  50  is disposed between the handrail  7  and the floor deck  22  in the front-rear direction. Accordingly, when the inspector on the floor deck  22  observes the level gauge  50  that exists in front of the floor deck  22 , the accidental falling of the inspector at the time of inspecting the cooling water is suppressed since the handrail  7  is provided in front of the level gauge  50 . 
     In the present embodiment, the supply port  14  and the cap  15  are disposed between the handrail  7  and the floor deck  22  in the front-rear direction. Since the handrail  7  is provided in front of the supply port  14  and the cap  15 , the accidental falling is also suppressed at the time of supplying the cooling water. 
     Moreover, in the present embodiment, the level gauge  50  is adjacent to the front end portion of the nonslip plate  24 . Therefore, the inspector observes the level gauge  50  in a state of being on the nonslip plate  24 , thereby suppressing the slipping of the inspector. 
     In the present embodiment, the level gauge  50  is disposed in front of the protector  31  of the dump body  3 . Accordingly, the illumination light, such as sunlight, is sufficiently applied onto the level gauge  50  without being blocked by the protector  31 . As a result, the driver can easily and surely observe the level gauge  50 . 
     Furthermore, in the present embodiment, the radiator  10  has the supply port  14  through which the cooling water is supplied, and the level gauge  50  is disposed so as to be adjacent to the supply port  14 . The level gauge  50 , the supply port  14 , and the cap  15  are linearly disposed in the front-rear direction. Therefore, when the inspector who has observed the level gauge  50  determines that the remaining amount of the cooling water is small, the inspector can supply the cooling water to the radiator  10  through the supply port  14  while observing the level gauge  50 . As a result, the inspector can supply an appropriate amount of the cooling water. 
     Moreover, in the present embodiment, at least the portion of the level gauge  50  is disposed at the inner side of the opening portion  71  provided in the portion of the cover member  70 . The level gauge  50  is protected by providing the cover member  70 . In addition, by disposing at least the portion of the level gauge  50  in the opening portion  71 , the inspector can observe the level gauge  50  through the opening portion  71  without removing the large cover member  70 . 
     In the embodiment described above, the housing member has been the radiator  10 , and the level gauge  50  has indicated the remaining amount of the cooling water in the radiator  10 . In addition, the fluid housed in the housing member has been the cooling water. However, the housing member that houses the liquid may be an oil tank which houses oil (working oil) for actuating hydraulic equipment, and the level gauge  50  may indicate a remaining amount of the oil as the fluid in the oil tank. Moreover, the housing member that houses the liquid may be a fuel tank which houses fuel in an internal combustion engine, and the level gauge  50  may indicate a remaining amount of the fuel as the fluid in the fuel tank. 
     In the embodiment described above, the longitudinal direction of the radiator  10  (housing member) and the left-right direction of the dump truck  1  have been the same. However, the longitudinal direction of the radiator  10  (housing member) and the front-rear direction of the dump truck  1  may be the same. Moreover, the level gauge  50  may be provided in the housing member so that the longitudinal direction of the level gauge  50  inclines to the left-right direction of the dump truck  1 , or the level gauge  50  may be provided in the housing member so that the longitudinal direction of the level gauge  50  inclines to the front-rear direction of the dump truck  1 . 
     In the embodiment described above, the working vehicle  1  has been the dump truck. However, the working vehicle  1  may be an excavator that has a lower traveling body, an upper swing body, and a working unit, or may be a wheel loader. 
     The present embodiment has been described above. However, the present embodiment is not limited to the content described above. In addition, the components described above may include components readily conceivable by those skilled in the art, components substantially identical, and components in a so-called equivalent range. Moreover, the components described above can be appropriately combined. Furthermore, various kinds of omission, replacement, and modification may be made in the components in the scope not departing from the gist of the present embodiment. 
     REFERENCE SIGNS LIST 
       1  Dump truck (working vehicle) 
       2  Vehicle main body 
       3  Dump body 
       4  Traveling device 
       5  Movable ladder 
       6  Inclined ladder 
       7  Handrail 
       8  Operating room 
       10  Radiator 
       11  Upper tank 
       11 A Upper surface 
       11 B Rear surface 
       12  Core tank 
       13  Lower tank 
       14  Supply port 
       15  Cap 
       21  Frame 
       22  Floor deck 
       23  Lower deck 
       24  Nonslip plate 
       31  Protector 
       41  Front wheel 
       42  Rear wheel 
       50  Gauge 
       60  Connecting member 
       61  First holding member 
       62  Second holding member 
       63  Base portion 
       70  Cover member 
       71  Opening portion 
       72  First lid 
       72 K First opening 
       73  Second lid 
       73 K Second opening