Construction machine

Abstract

To provide a construction machine capable of storing water generated by a fuel cell unit without stagnation.SOLUTION: Since wastewater discharged from a drain port 43 of the fuel cell unit 42 mounted on the upper rotating body 2 is received by a lower tank 80 located on a lower carriage 1, which is located below an upper rotating body 2, the wastewater is prevented from accumulating on the upper rotating body 2 side. Also, when the relative angle θ of the upper rotating body 2 to the lower carriage 1 is within a specified range (-α to +α), since a switching valve 36 is switched to the allowable state, the wastewater falling from the outlet 32 of the drain pipe 30 is received by the lower tank 80.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present disclosure relates to a construction machine driven by a fuel cell device as a power source. [Background technology]

[0002] Machines that are driven by fuel cell devices have been proposed. Examples include the machines described in Patent Documents 1 and 2. The machines described in Patent Documents 1 and 2 are equipped with a storage unit (tank) that stores water produced as the fuel cell device generates electricity. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-154283 [Patent Document 2] Japanese Patent Application Laid-Open No. 2007-242434 Summary of the Invention [Problem to be solved by the invention]

[0004] However, if a reservoir for storing water generated by a fuel cell device is located near the fuel cell device, and water accumulates in the piping connecting the fuel cell device and the reservoir, this can hinder the drainage of the water generated by the fuel cell device, resulting in a decrease in the operating efficiency of the fuel cell device. In particular, at low temperatures, there is a risk that the accumulated water will freeze in the piping, which could further reduce the operating efficiency of the fuel cell device.

[0005] The present disclosure has been made to solve the above-mentioned problems, and its purpose is to provide a construction machine that can store water generated by a fuel cell device in a storage section without stagnating. [Means for solving the problem]

[0006] The construction machine of the first aspect comprises a lower running body, an upper rotating body supported rotatably relative to the lower running body, a fuel cell device mounted on the upper rotating body, a drain pipe connected to an device drain outlet formed in the fuel cell device, a storage section disposed on the lower running body and receiving water discharged from the outlet of the drain pipe, a switching valve that switches between an allowable state that allows drainage from the drain pipe and a blocked state that blocks drainage from the drain pipe, and a controller that controls the switching valve, wherein the controller switches the switching valve to the allowable state when the relative angle of the upper rotating body to the lower running body is within a predetermined range, the predetermined range being an angle range in which the storage section can receive water discharged from the outlet of the drain pipe.

[0007] In the construction machine according to the first aspect, water generated by the fuel cell device can be stored in a storage unit located on the undercarriage, which is located away from the fuel cell device. Specifically, water discharged from the drainage outlet of the fuel cell device mounted on the upper rotating body is received in a storage unit located on the undercarriage, which is located below the upper rotating body, preventing water from accumulating in the upper rotating body. Furthermore, when the relative angle of the upper rotating body to the undercarriage is within a predetermined range, the switching valve is switched to an allowable state, allowing the storage unit to receive water discharged from the outlet of the drain pipe. This allows the storage unit to be made smaller.

[0008] A construction machine according to a second aspect is preferably the construction machine according to the first aspect, further comprising the following feature: That is, the construction machine according to the second aspect includes a sensor that detects the swing angular velocity of the upper swing body, and the controller switches to the permissive state when the relative angle is within the predetermined range and the swing angular velocity is equal to or less than a predetermined speed threshold. If the swing angular velocity is fast, even if the relative angle is within the predetermined range, water discharged from the outlet of the drain pipe will splash outward due to centrifugal force, making it difficult to collect in the storage section. In contrast, according to the second aspect, by switching to the permissive state only when the swing angular velocity is equal to or less than the predetermined speed threshold, water can be collected in the storage section without splashing outward.

[0009] It is preferable that the construction machine according to the third aspect further comprises the following feature in addition to the construction machine according to the first or second aspect. That is, in the construction machine according to the third aspect, the drain pipe is provided with a second storage section along its route that can temporarily store water flowing through the drain pipe. According to the third aspect, by temporarily storing water flowing through the drain pipe in the second storage section, it is possible to prevent water flowing through the drain pipe from flowing toward the fuel cell device even if the switching valve is switched to the blocked state.

[0010] It is preferable that the construction machine according to the fourth aspect is the construction machine according to the third aspect, further comprising the following feature: That is, the construction machine according to the fourth aspect includes a sensor that detects the amount of water stored in the second storage section, and when the stored amount becomes equal to or exceeds a predetermined storage amount threshold, the controller rotates the upper rotating body until the relative angle falls within the predetermined range, or notifies the operator to rotate the upper rotating body until the relative angle falls within the predetermined range. According to the fourth aspect, when there is a risk that the amount of water stored in the second storage section will exceed the allowable amount, the upper rotating body can be rotated in advance to drain the water stored in the second storage section.

[0011] A construction machine according to a fifth aspect is preferably the construction machine according to any one of the first to fourth aspects, further comprising the following feature: In other words, in the construction machine according to the fifth aspect, the storage section is fitted with an openable drain plug for discharging water stored in the storage section to the outside of the storage section. According to the fifth aspect, the water stored in the storage section can be discharged at an appropriate time. For example, at a work site where drainage is not desirable, the drainage can be prevented by closing the drain plug.

[0012] A construction machine according to a sixth aspect is preferably the construction machine according to any one of the first to fifth aspects, further comprising the following feature: In other words, in the construction machine according to the sixth aspect, the storage unit is detachable from the lower traveling body. According to the sixth aspect, the storage unit can be removed from the lower traveling body and carried to a location where it can be drained.

[0013] It is preferable that the construction machine according to the seventh aspect further comprises the following feature in addition to the construction machine according to any one of the first to sixth aspects. That is, in the construction machine according to the seventh aspect, the storage section has an opening at the top, and the opening is located vertically below the outlet of the drainage pipe when the relative angle is within the predetermined range. According to the seventh aspect, when the relative angle is within the predetermined range, the opening of the storage section is located vertically below the outlet of the drainage pipe, so that when the switching valve is switched to the allowing state, water falling from the outlet of the drainage pipe is poured into the storage section through the opening. [Effects of the Invention]

[0014] According to the present disclosure, a construction machine is provided that is capable of storing water produced by a fuel cell device at a location away from the fuel cell device. [Brief explanation of the drawings]

[0015] [Figure 1] FIG. 1 is a side view showing a construction machine according to an embodiment. [Figure 2] 2 is a diagram showing the inside of a machine room of the construction machine of FIG. 1, and is a cross-sectional view taken along line II-II of FIG. [Figure 3] FIG. 2 is a perspective view showing the vehicle frame and the fuel cell device. [Figure 4] FIG. 4 is an enlarged perspective view of a portion surrounded by a dashed line in FIG. 3. [Figure 5] 5 is a right side view of the part shown in FIG. 4 as seen in the direction indicated by arrow V. FIG. [Figure 6] FIG. 2 is a schematic diagram showing a structure for guiding water discharged from a drain outlet of a fuel cell device to a tank. [Figure 7]FIG. 10 is a diagram showing the positions of the lower tank and the outlet of the drain pipe. [Figure 8] 4 is a flowchart illustrating the control operation of a controller. [Figure 9] FIG. 10 is a schematic diagram showing a structure for guiding wastewater discharged from a fuel cell device to a lower tank, according to a second embodiment. [Figure 10] 10A and 10B are views showing another aspect of the opening formed in the lower tank. DETAILED DESCRIPTION OF THE INVENTION

[0016] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings.

[0017] [Overall structure] 1 and 2, the construction machine 10 includes a lower traveling structure 1 including a traveling device, an upper rotating structure 2 supported to be rotatable relative to the lower traveling structure 1 about a vertically extending rotation axis Z (rotation center), and a working device 3 supported by the upper rotating structure 2. The construction machine 10 according to this embodiment is a hydraulic excavator, but the construction machine in this disclosure is not limited to hydraulic excavators and may be other construction machines such as a crane or a bulldozer. The traveling device may be a crawler traveling device as shown in FIG. 1, or may be a traveling device having tires (not shown).

[0018] The front-rear direction and left-right direction shown in the drawings are directions based on the orientation of the upper rotating body 2. Specifically, the front-rear direction is a horizontal direction parallel to the longitudinal direction of the working device 3 in a plan view, and the left-right direction is a horizontal direction perpendicular to the front-rear direction.

[0019] The work device 3 includes a boom 4 that is attached to the upper rotating body 2 so that it can be raised and lowered, an arm 5 that is attached to the boom 4 so that it can rotate, and a tip attachment 6 that is attached to the arm 5 so that it can rotate. In this embodiment, the tip attachment 6 is a bucket, but the tip attachment may be another tip attachment such as a grapple, fork, or crusher.

[0020] The upper rotating body 2 is disposed above the undercarriage 1. The upper rotating body 2 includes a machine frame 20, a cab 11 supported by the machine frame 20, a counterweight 12, and an outer wall 13. The outer wall 13 has, for example, a box shape and defines a machine room 14. Various pieces of equipment are housed inside the machine room 14. The various pieces of equipment housed in the machine room 14 will be described later.

[0021] The machine frame 20 is a member that is rotatably supported on the undercarriage 1. The machine frame 20 includes a frame main body 21 and a rising body 22. The frame main body 21 supports the cab 11 and the outer wall 13. The frame main body 21 has an upper surface that extends in the front-to-rear and left-to-right directions and is large enough to support the cab 11 and the outer wall 13. The rising body 22 supports the boom 4 so that it can be raised and lowered. The rising body 22 includes a boom mounting portion 22A to which the base end portion 4A of the boom 4, shown by the dashed line in FIG. 1, is attached. The boom mounting portion 22A forms the front portion of the rising body 22.

[0022] The cab 11 is disposed, for example, at the left front portion of the frame body 21. The counterweight 12 is a weight for balancing, and is disposed at the rear of the frame body 21 or further rearward than the frame body 21. The cab 11 is equipped with a driver's seat, operating levers, operating pedals, etc.

[0023] 1, the rising body 22 has a shape that stands up from the frame main body 21 and extends in the front-to-rear direction. The rising body 22 includes a rear portion 22B that is located rearward of the boom mounting portion 22A (front portion). The rear portion 22B is located rearward of the boom mounting portion 22A and is lower in height than the boom mounting portion 22A.

[0024] 1, 2, and 3, the upright body 22 includes left and right upright plates 23, 23 that face each other at a distance from each other on the left and right. Each of the left and right upright plates 23, 23 is a plate-like member that stands upright from the frame main body 21 and is disposed so as to extend in the front-rear direction.

[0025] The construction machine 10 is equipped with a plurality of actuators. Each of the plurality of actuators is operated by receiving a supply of hydraulic oil discharged from a hydraulic pump 62 (described later). The plurality of actuators include a boom cylinder 7 for raising and lowering the boom 4, an arm cylinder 8 for rotating the arm 5, a tip attachment cylinder 9 for rotating the tip attachment 6, and a hydraulic motor 64 for rotating the upper rotating body 2 relative to the lower traveling body 1.

[0026] The machinery room 14 accommodates a plurality of equipment groups, which will be described later. The machinery room 14 is formed in the space on the top surface of the frame body 21, excluding the area where the cab 11 is located, the area where the base end 4A of the boom 4 is attached, and the area where the counterweight 12 is located. The machinery room 14 may be formed, for example, in a rear space that is the space behind the cab 11, or in a side space that is the space to the side (for example, to the right) of the cab 11, or may be formed in both the rear space and the side space. Note that if the weight of the equipment accommodated inside the machinery room 14 is heavy, the counterweight 12 can be omitted.

[0027] The outer wall 13 has, for example, a box shape and defines a machine chamber 14. As shown in FIGS. 1 and 2 , an air intake port 16 and an exhaust port 17 are formed in the outer wall 13. The air intake port 16 is an opening for drawing air outside the machine chamber 14 into the machine chamber 14 as cooling air CA. The exhaust port 17 is an opening for discharging the cooling air CA inside the machine chamber 14 to the outside of the machine chamber 14. There are no particular limitations on the locations where the air intake port 16 and the exhaust port 17 are formed, but in this embodiment, the air intake port 16 is formed on a side portion (e.g., the right side) of the outer wall 13, and the exhaust port 17 is formed on another side portion (e.g., the left side) of the outer wall 13.

[0028] The construction machine 10 includes a plurality of equipment groups. The plurality of equipment groups include a hydrogen equipment group 40, a high-voltage equipment group 50, a hydraulic equipment group 60, and a cooling equipment group 70. In the specific example shown in Fig. 2, the hydrogen equipment group 40 is arranged in an area near the center of the rear of the upper rotating body 2, the cooling equipment group 70 is arranged in an area near the left side of the rear of the upper rotating body 2, and the high-voltage equipment group 50 and the hydraulic equipment group 60 are arranged in areas other than these, but the areas in which each equipment group is arranged are not limited to the specific example shown in Fig. 2.

[0029] The hydrogen equipment group 40 includes a hydrogen tank 41, a fuel cell device 42, and a hydrogen filling port 44. The hydrogen tank 41 is connected to the fuel cell device 42 via a fuel pipe 40A. The hydrogen filling port 44 is connected to the hydrogen tank 41 via a hydrogen filling pipe 40B.

[0030] The hydrogen tank 41 is a container for storing hydrogen. In this embodiment, the hydrogen tank 41 is disposed above the fuel cell device 42. The hydrogen tank 41 may be supported by a tank support member (not shown) in the machine room 14. A pressure reducing valve 45 may be disposed in the fuel pipe 40A. In this case, the high-pressure hydrogen stored in the hydrogen tank 41 is reduced in pressure by the pressure reducing valve 45. The reduced-pressure hydrogen is supplied to the fuel cell device 42 via the fuel pipe 40A.

[0031] The fuel cell device 42 is mounted on the upper rotating body 2 and includes a fuel cell 42A. The fuel cell 42A generates electricity (power) by causing an electrochemical reaction between hydrogen supplied from the hydrogen tank 41 and oxygen (for example, oxygen contained in the air). The fuel cell 42A may be configured, for example, by a fuel cell stack including a plurality of cells.

[0032] The hydrogen filling port 44 has a filling port that communicates with the hydrogen filling pipe 40B. During the filling operation of filling the hydrogen tank 41 with hydrogen, a nozzle of a hydrogen gas filling device (not shown) is connected to the hydrogen filling port 44, thereby filling the hydrogen tank 41 with hydrogen. Once filling of the hydrogen tank 41 with hydrogen is complete, the nozzle of the hydrogen gas filling device is removed from the hydrogen filling port 44.

[0033] The high-voltage equipment group 50 includes an inverter 51 and an electric motor 52. The inverter 51 is connected to the fuel cell device 42 by a cable (not shown). The inverter 51 is connected to the electric motor 52 by a cable (not shown).

[0034] The inverter 51 converts the direct current supplied from the fuel cell device 42 into a three-phase alternating current and supplies it to the electric motor 52. The inverter 51 adjusts the rotation speed of the electric motor 52.

[0035] The electric motor 52 is a drive source that drives the hydraulic pump 62. The electric motor 52 is operated by receiving a supply of electric power from the fuel cell device 42 via an inverter 51. The electric motor 52 is configured as, for example, a three-phase motor.

[0036] The high-voltage equipment group 50 may further include a battery 53. The battery 53 may be, for example, a lithium-ion battery or another type of battery. The electric motor 52 may be operated by receiving power output from the battery 53 via an inverter 51. The inverter 51 may convert the direct current supplied from the battery 53 into three-phase alternating current and supply it to the electric motor 52. The battery 53 may also be charged by receiving power from the fuel cell device 42.

[0037] The high-voltage equipment group 50 may further include a repeater (junction box) 55. The repeater 55 has a function of combining the power output by the fuel cell device 42 and the power output by the battery 53, and a function of distributing the power to a plurality of high-voltage equipment such as the inverter 51 and a converter 54 described below.

[0038] The high-voltage equipment group 50 may further include a converter 54 (DC-DC converter). The converter 54 steps down the high voltage output from the repeater 55. The converter 54 supplies the stepped-down low-voltage power to the low-voltage equipment group.

[0039] The hydraulic equipment group 60 includes a hydraulic oil tank 61, a hydraulic pump 62, a control valve 63, and a hydraulic motor 64. The hydraulic oil tank 61 is a container that stores hydraulic oil. The hydraulic pump 62 is driven by the electric motor 52 and discharges hydraulic oil. The hydraulic pump 62 is connected to the electric motor 52 via a shaft connection coupling (not shown). The hydraulic motor 64 is operated by receiving hydraulic oil from the hydraulic pump 62 via a control valve 63. The control valve 63 opens and closes in response to a lever operation or pedal operation applied by the operator to an operating device (not shown) so that hydraulic oil from the hydraulic pump 62 is supplied to an actuator corresponding to that operation.

[0040] The cooling equipment group 70 includes a cooling fan 71 and a heat exchanger. The heat exchanger may include at least one of an oil cooler 72 and a radiator 73.

[0041] The cooling fan 71 forms a flow of cooling air CA in the machine room 14. That is, the cooling fan 71 forms a flow of cooling air CA in the machine room 14 from the intake port 16 to the exhaust port 17. The cooling fan 71 has an impeller including a rotating shaft and a plurality of blades arranged along the outer periphery of the rotating shaft, and a fan motor that drives the impeller. The impeller of the cooling fan 71 rotates when power is supplied to the fan motor from the fuel cell device 42 or the battery 53 via the repeater 55, for example. The cooling fan 71 may further have a shroud that is arranged to surround the impeller.

[0042] The oil cooler 72 may be configured to cool the hydraulic oil discharged from the equipment included in the hydraulic equipment group 60. The hydraulic oil discharged from the control valve 63 reaches the oil cooler 72 via an oil cooler hose (not shown), where it is cooled by heat exchange with cooling air CA, and then returns to the hydraulic oil tank 61 via the oil cooler hose (not shown). In this way, the hydraulic oil is cooled.

[0043] The radiator 73 may be configured to cool the fuel cell device 42. Specifically, for example, the radiator 73 may be connected to the fuel cell device 42 via radiator hoses 74 and 75. Coolant is circulated between the fuel cell device 42 and the radiator 73 by a water pump. The coolant is cooled by heat exchange with the cooling air CA in the radiator 73, and is supplied to the fuel cell device 42 via the radiator hose 74. In this way, the fuel cell device 42 is cooled by the coolant. The coolant that has passed through the fuel cell device 42 returns to the radiator 73 via the radiator hose 75.

[0044] [First embodiment] Next, the features of the construction machine 10 according to this embodiment will be described with reference to FIGS.

[0045] The fuel cell device 42 has an device drain outlet 43 for discharging water generated within the fuel cell device 42 as wastewater. The construction machine 10 is provided with a drain pipe 30 connected to the device drain outlet 43 formed in the fuel cell device 42. The drain pipe 30 is positioned at a height equal to or lower than the device drain outlet 43.

[0046] The drain pipe 30 has a pipe inlet 31 connected to the device drain outlet 43, and is located at a height below the pipe inlet 31. The drain pipe 30 may be arranged so that the entire drain pipe 30 is at the same height as the device drain outlet 43, but it is preferable that the pipe inlet 31 of the drain pipe 30 and the base end portion nearby are at the same height as the device drain outlet 43, and that the portion other than the pipe inlet 31 and the base end portion is lower than the device drain outlet 43.

[0047] The fuel cell device 42 may include a case 42B that houses the fuel cell 42A, and in this case, the device drain outlet 43 may be formed in the case 42B. In this embodiment, the device drain outlet 43 is formed in the side surface of the case 42B, but the location where the device drain outlet 43 is formed is not limited to the side surface of the case 42B, and may be, for example, the bottom surface or the top surface of the case 42B. More specifically, the device drain outlet 43 is formed in the lower part of the side surface of the case 42B.

[0048] In the fuel cell device 42, water (water vapor) is produced by a chemical reaction, and the produced water is discharged from the device drain outlet 43. The water discharged from the device drain outlet 43 of the fuel cell device 42 may contain both liquid water and gaseous vapor (water vapor), or may contain only either liquid water or gaseous vapor.

[0049] The drain pipe 30 has an outlet 32. The outlet 32 ​​is an outlet of the drain pipe 30 that is connected to an apparatus outlet 43. The outlet 32 ​​discharges water generated in the fuel cell apparatus 42 as wastewater. The outlet 32 ​​is located lower than the apparatus outlet 43. In this case, water in the drain pipe 30 is more easily discharged from the outlet 32, making it less likely that water will stagnate in the drain pipe 30.

[0050] The drain pipe 30 is provided with an upper tank 34 along its path, capable of temporarily storing water flowing through the drain pipe 30. The upper tank 34 may be rectangular or cylindrical. In other words, the shape of the upper tank 34 is not limited as long as it can temporarily store water flowing through the drain pipe 30. The upper tank 34 includes an upper wall 34a located above, a bottom wall 34b located below, and a side wall 34c connecting the upper wall 34a and the bottom wall 34b. The side wall 34c extends vertically from the edges of the upper wall 34a and the bottom wall 34b. The upper tank 34 is formed with an exhaust hole 35 that communicates with the outside. Steam and other contaminants contained in the wastewater are discharged to the outside through the exhaust hole 35. The exhaust hole 35 is preferably formed, for example, in the upper part of the upper wall 34a or the side wall 34c. The upper tank 34 is an example of a second storage unit of the present disclosure.

[0051] In connection with the placement of the upper tank 34 on the path of the drain pipe 30, the drain pipe 30 is divided into an upper drain pipe 30A connecting the fuel cell device 42 and the upper tank 34, and a lower drain pipe 30B positioned below the upper tank 34.

[0052] The lower end of the upper drain pipe 30A is connected to, for example, the upper wall 34a of the upper tank 34. The upper drain pipe 30A may be connected to the side wall 34c. In this case, it is preferable that the upper drain pipe 30A is connected to a part of the side wall 34c above the center in the vertical direction. The upper drain pipe 30A does not have a portion that extends upward. This prevents water from accumulating in the upper drain pipe 30A.

[0053] The lower drain pipe 30B is connected, for example, to the bottom wall 34b of the upper tank 34. The lower drain pipe 30B may be connected to the side wall 34c of the upper tank 34. In this case, the lower drain pipe 30B is preferably connected to a portion of the side wall 34c near the bottom wall 34b. The lower drain pipe 30B passes through an opening 24 formed in the machine body frame 20 and extends to a position below the machine body frame 20. An outlet 32 ​​is formed at the lower end of the lower drain pipe 30B. The outlet 32 ​​is located below the device drain port 43 and on the underside of the machine body frame 20 of the upper rotating body 2 or below the underside. The lower drain pipe 30B does not have a portion extending upward. This prevents water from accumulating in the lower drain pipe 30B.

[0054] A switching valve 36 is attached to the lower drain pipe 30B. The switching valve 36 switches between an allowable state, which allows drainage from the outlet 32 ​​of the drain pipe 30, and a blocked state, which blocks drainage from the outlet 32 ​​of the drain pipe 30. When the switching valve 36 is switched to the allowable state, water stored in the upper tank 34 is discharged from the outlet 32. When the switching valve 36 is switched to the blocked state, water is not discharged from the outlet 32. Even when the switching valve 36 is switched to the blocked state, water discharged from the fuel cell device 42 is stored in the upper tank 34, so water does not accumulate near the fuel cell device 42. The volume of the upper tank 34 is determined in advance experimentally or by design, and is set to a size that will not cause the upper tank 34 to become full even if the switching valve 36 is switched to the blocked state for a predetermined period of time. The operating state of the switching valve 36 is controlled by a controller 110 (see FIG. 6), which will be described later.

[0055] Next, we will explain how to treat the water (wastewater) discharged from the outlet 32 ​​of the drain pipe 30. If water were to freely discharge from the outlet 32, it could adhere to the metal parts of the lower running body 1 located below the outlet 32. This could lead to rusting of the parts of the lower running body 1 to which the water adheres. Furthermore, depending on the work site, there may be locations where drainage is undesirable, resulting in undesirable wastewater. To prevent this, in this embodiment, the lower running body 1 is provided with a lower tank 80 that receives the water (wastewater) discharged from the outlet 32 ​​of the drain pipe 30. This allows the water generated by the fuel cell device 42 to be stored in the lower tank 80, which is located away from the fuel cell device 42. This prevents water from accumulating in the fuel cell device 42, thereby preventing rust on the lower running body 1 and wastewater in undesirable locations. The lower tank 80 is an example of a storage unit in the present disclosure.

[0056] 6 is a cross-sectional view of the construction machine 10 cut along a plane passing through the rotation axis Z, and is a diagram that schematically shows the structure that guides wastewater (including steam) discharged from the drain outlet of the fuel cell device 42 to the lower tank 80. Note that because FIG. 6 is a diagram that schematically shows the structure that guides wastewater discharged from the fuel cell device 42 to the lower tank 80, the scale and shape do not necessarily match those of FIGS. 1 to 5 described above.

[0057] As shown in FIG. 6, a lower tank 80 is disposed on a lower traveling body 1. The lower traveling body 1 includes a pair of left and right crawlers 84L, 84R and a car body 82 connecting the pair of left and right crawlers 84L, 84R. The crawler 84L includes a crawler frame 85L extending in one direction, two wheels 86L (see FIG. 1) and a wheel 87L (see FIG. 1) rotatably supported on one end and the other end of the crawler frame 85L, respectively, and an annular (endless) crawler belt 89L supported by the two wheels 86L, ​​87L. The crawler 84R includes a crawler frame 85R extending in one direction, two wheels 86R (see FIG. 1) and a wheel 87R (see FIG. 1) rotatably supported on one end and the other end of the crawler frame 85R, and an annular (endless) crawler belt 89R supported by the two wheels 86R, 87R. Each of the crawler belts 89L, 89R has a number of crawler shoes 91 connected to each other.

[0058] The car body 82 includes an upper body 82a and a lower body 82b disposed below the upper body 82a. The upper body 82a and the lower body 82b are connected to a crawler frame 85L of the crawler 84L and a crawler frame 85R of the crawler 84R, respectively.

[0059] A space S is formed between the upper body 82a and the lower body 82b, and a portion of the lower tank 80 is housed in this space S. Specifically, the lower tank 80 passes through a through-hole 81 formed in the lower body 82b, and the lower part of the lower tank 80 is disposed within the space S.

[0060] The lower tank 80 is formed, for example, in a cylindrical shape with an opening 78 at its top. In this case, the lower tank 80 includes a disk portion 80a and a cylindrical portion 80b extending upward from the outer edge of the disk portion 80a. The disk portion 80a may be disposed in direct contact with the lower body 82b, or may be supported by a support base installed on the lower body 82b. The cylindrical portion 80b passes through a through-hole 81 formed in the upper body 82a and protrudes to the outside of the car body 82. The lower tank 80 is not limited to a cylindrical shape and may be, for example, a rectangular parallelepiped shape. In other words, the shape of the lower tank 80 is not limited as long as it has an opening for receiving water falling from above.

[0061] The lower tank 80 is disposed in a position where it can receive water dropping from the discharge port 32 of the drain pipe 30. Specifically, the lower tank 80 is disposed vertically below the discharge port 32 in the state shown in Fig. 6. That is, when the distance between the pivot axis Z and the discharge port 32 is defined as a radius R1 and the distance between the pivot axis Z and the center of the lower tank 80 is defined as a radius R2, it is preferable that the radius R1 is equal to or approximately equal to the radius R2.

[0062] FIG. 7 is a diagram showing the relative positions of the lower tank 80 and the discharge port 32 of the drain pipe 30, and corresponds to a view of the lower tank 80 and the discharge port 32 viewed vertically from above. As shown in FIG. 7, it is preferable that the radius R1 between the pivot axis Z and the center of the lower tank 80, i.e., the center of the disk portion 80a, is equal to the radius R2 between the pivot axis Z and the center of the discharge port 32. This allows the opening 78 of the lower tank 80 to receive water dropping from the discharge port 32 if an imaginary circle representing the discharge port 32 is located within the area SA of the opening 78 (the hatched area in FIG. 7). In this regard, it is preferable that the inner diameter d1 of the opening 78 be larger than the inner diameter d2 of the discharge port 32.

[0063] The discharge outlet 32 ​​moves along an imaginary circle CR of radius R2 centered on the rotation axis Z in conjunction with the upper rotating body 2. That is, the discharge outlet 32 ​​moves relative to the lower tank 80 in conjunction with the upper rotating body 2. As a result, when the circle representing the discharge outlet 32 ​​is located, for example, at the position shown by the dashed line with respect to the lower tank 80, the discharge outlet 32 ​​is outside the area SA of the opening 78, and therefore, water dropping from the discharge outlet 32 ​​cannot be received by the opening 78 of the lower tank 80.

[0064] On the other hand, if the circle representing the discharge outlet 32 ​​is within the area SA of the opening 78, the opening 78 is positioned vertically below the discharge outlet 32, and water dropping from the discharge outlet 32 ​​can be received by the opening 78 of the lower tank 80. Specifically, when the relative angle θ of the discharge outlet 32 ​​with respect to the lower tank 80 is within a predetermined angle range (-α<θ<+α) shown in FIG. 7, the opening 78 of the lower tank 80 is positioned vertically below the discharge outlet 32, and water dropping from the discharge outlet 32 ​​can be received by the lower tank 80. The relative angle θ is based (zero) on the state where the center of the lower tank 80 and the center of the discharge outlet 32 ​​are aligned, that is, the state where the circle representing the discharge outlet 32 ​​in FIG. 7 is at the position indicated by the solid line.

[0065] The angles (-α) and (+α) shown in FIG. 7 are thresholds of the relative angle θ at which the water dropping from the discharge port 32 can be received by the lower tank 80, i.e., the threshold at which the entire circle representing the discharge port 32 falls within the area SA of the opening 78 shown in FIG. 7. The states where the relative angle θ is angle (-α) and angle (+α) respectively correspond to the states where the circle representing the discharge port 32 is located at the position indicated by the dashed line in FIG. 7. Therefore, the predetermined range (-α to +α) of the relative angle θ is the angle range at which the water discharged from the discharge port 32 can be received by the lower tank 80. Note that the discharge port 32 is linked to the upper revolving body 2, and the lower tank 80 is disposed on the lower running body 1. Therefore, the relative angle θ of the discharge port 32 with respect to the lower tank 80 is the same as the relative angle θ of the upper revolving body 2 with respect to the lower running body 1.

[0066] Furthermore, it is preferable that the lower tank 80 be fitted with an openable drain plug for discharging wastewater stored in the lower tank 80 to the outside of the lower tank 80. From the viewpoint of workability, it is more preferable that this drain plug be a drain cock 92 that can be opened and closed manually or electrically. In this case, the drain cock 92 is disposed in a drain pipe 90 connected to the lower tank 80. The drain cock 92 is an example of a drain plug of the present disclosure.

[0067] Drain pipe 90 is connected to, for example, disk portion 80a of lower tank 80, passes through a through-hole 93 formed in lower body 82b of lower traveling body 1, and extends to a position below lower body 82b. Drain pipe 90 may also be connected to cylindrical portion 80b. In this case, drain pipe 90 is preferably connected below the center position in the height direction of cylindrical portion 80b.

[0068] The drain cock 92 is disposed, for example, near the outlet of the drain pipe 90. The drain cock 92 may be a manual type that is opened and closed manually by an operator, or may be an electric type that is operated by turning on and off a selector switch disposed in the cab 11, for example. By disposing the drain cock 92, it is possible to discharge the wastewater stored in the lower tank 80 at an appropriate time. For example, at a work site where drainage is not desirable, unintentional drainage of water from the lower tank 80 can be avoided by closing the drain cock 92. In addition, a sensor that detects the amount of water stored in the lower tank 80 may be disposed, and a configuration may be adopted in which, when the amount of water stored in the lower tank 80 reaches or exceeds a predetermined amount, the sensor notifies the operator that the lower tank 80 needs to be drained.

[0069] A slewing bearing 96 that functions as a slewing ring for the upper slewing body 2 is disposed directly below the machine body frame 20. The slewing bearing 96 supports the upper slewing body 2 so that it can slew relative to the lower running body 1. The slewing bearing 96 includes an annular inner ring 96a disposed on the lower running body 1, an annular outer ring 96b disposed on the upper slewing body 2, and a plurality of balls 96c interposed between the inner ring 96a and the outer ring 96b. The outer ring 96b is disposed on the outer peripheral side of the inner ring 96a and is fitted onto the inner ring 96a via the plurality of balls 96c so as to be rotatable relative to the inner ring 96a.

[0070] Internal teeth 98 are formed on the inner peripheral surface of the inner ring 96a. The internal teeth 98 mesh with a pinion gear 102 driven by a swing motor 100. The swing motor 100 is disposed on the upper swing body 2 side. A reducer may be interposed between the swing motor 100 and the pinion gear 102.

[0071] The outer wheel 96b is fixed to the machine frame 20 with a plurality of bolts 104 and is rotatable about the rotation axis Z together with the machine frame 20, i.e., the upper rotating body 2. When the pinion gear 102 rotates, the rotation motor 100 revolves around the rotation axis Z. At this time, the outer wheel 96b rotates, and the upper rotating body 2 is rotated about the rotation axis Z together with the rotation motor 100.

[0072] The operating state of the swing motor 100 is controlled by a controller 110. The controller 110 is configured by a computer including a central processing unit (a processing unit such as a CPU) (not shown) and storage devices such as a ROM and RAM (not shown), and executes various processes including the operation control of the swing motor 100.

[0073] The controller 110 receives various signals, including a signal representing the relative angle θ of the upper rotating body 2 with respect to the lower running body 1 and a signal representing the rotation angular velocity ω of the upper rotating body 2, which are detected by a rotation angle sensor 112, a signal representing the rotation speed Np of the pinion gear 102 of the rotation motor 100, which is detected by a motor rotation speed sensor 114, and a signal representing the amount Q of water stored in the upper tank 34, which is detected by a storage amount sensor 116.

[0074] The controller 110 controls the operating state of the swing motor 100, the switching valve 36, etc. based on various information detected by various sensors (such as the relative angle θ of the upper swing body 2, the swing angular velocity ω of the upper swing body 2, and the storage volume Q of the upper tank 34).

[0075] [Control mode] A specific control mode by the controller 110 will be described below.

[0076] The controller 110 determines whether the relative angle θ of the upper revolving body 2 with respect to the lower traveling body 1 detected by the rotation angle sensor 112 is within a predetermined range (-α to +α). The relative angle θ is set to a reference (zero) at the angle at which the center of the discharge port 32 and the center of the lower tank 80 coincide.

[0077] The controller 110 also determines whether the rotation angular velocity ω of the upper rotating body 2 detected by the rotation angle sensor 112 is equal to or less than a predetermined speed threshold β. The speed threshold β is determined in advance experimentally or by design, and is set to an upper limit threshold at which the water dropping from the discharge port 32 does not scatter due to centrifugal force, i.e., an upper limit threshold at which the water dropping from the discharge port 32 can be poured into the lower tank 80. The speed threshold β may be set to a value close to zero, for example.

[0078] When the relative angle θ is within a predetermined range and the swing angular velocity ω is equal to or less than the velocity threshold value β, the controller 110 switches the switching valve 36 to the above-described permissive state, i.e., a state that allows drainage from the outlet 32. As a result, water falls from the outlet 32, and the drainage water that falls is poured into the opening 78 of the lower tank 80 without splashing outside, and is stored in the lower tank 80. As a result, even if the lower tank 80 is small, the water that falls from the outlet 32 ​​can be received by the lower tank 80.

[0079] On the other hand, when at least one of the following conditions is met: the relative angle θ is outside a predetermined range, and the swing angular velocity ω exceeds the velocity threshold value β, the controller 110 switches the switching valve 36 to a blocked state, i.e., a state in which water is not discharged from the discharge port 32. As a result, when it is difficult for the lower tank 80 to receive the water dropping from the discharge port 32, the water is not discharged from the discharge port 32, and therefore, the water discharged from the discharge port 32 is prevented from adhering to the undercarriage 1. Note that while the switching valve 36 is switched to the blocked state, the water discharged from the fuel cell device 42 is stored in the upper tank 34.

[0080] Furthermore, when the storage volume Q of the upper tank 34 detected by the storage volume sensor 116 becomes equal to or greater than a predetermined storage volume threshold γ, the controller 110 rotates the upper rotating body 2 until the relative angle θ falls within a predetermined range (−α to +α). The storage volume threshold γ is determined in advance experimentally or by design and is set to a threshold value at which the upper tank 34 may become full of water. By rotating the upper rotating body 2 until the relative angle θ falls within the predetermined range, water falling from the outlet 32 ​​can be received by the lower tank 80. In this state, the controller 110 switches the switching valve 36 to the permissive state, allowing water to fall from the outlet 32 ​​and be received by the lower tank 80. As a result, the storage volume Q of the upper tank 34 decreases, preventing the upper tank 34 from becoming full of water and flowing toward the fuel cell device 42. When rotating the upper rotating body 2, it is preferable to notify the worker in advance of the planned rotation by using at least one of a voice and a monitor disposed in the cab 11. This makes it possible to prevent the worker from rotating unintentionally.

[0081] Alternatively, when the storage volume Q of the upper tank 34 becomes equal to or greater than the storage volume threshold value γ, the controller 110 notifies the operator to rotate the upper rotating body 2 until the relative angle θ falls within a predetermined range. The operator may be notified by sound such as voice, or by text or the like on a monitor located in the cab 11, or both. The construction machine 10 may also be equipped with an alarm 120. The alarm 120 is configured to issue an alarm to rotate the upper rotating body 2 at a timing according to a command from the controller 110.

[0082] In response to the notification, the operator rotates the upper rotating body 2 until the relative angle θ falls within a predetermined range, thereby allowing the water dropping from the outlet 32 ​​to be received in the lower tank 80. In this state, the controller 110 switches the switching valve 36 to the permissive state, causing water to drop from the outlet 32 ​​and be received in the lower tank 80. As a result, the storage volume Q of the upper tank 34 decreases, preventing the upper tank 34 from becoming full of water and flowing toward the fuel cell device 42.

[0083] 8 is a flowchart illustrating the control operation of the controller 110. The controller 110 repeatedly executes the flowchart shown in FIG.

[0084] First, the controller 110 detects the relative angle θ of the upper rotating body 2 with respect to the lower traveling body 1 (step S10). Next, the controller 110 detects the swing angular velocity ω of the upper rotating body 2 (step S20). The controller 110 determines whether the detected swing angular velocity ω is equal to or less than a velocity threshold value β (step S30). If the swing angular velocity ω exceeds the velocity threshold value β (NO in step S30), the controller 110 proceeds to step S60, which will be described later. If the swing angular velocity ω is equal to or less than the velocity threshold value β (YES in step S30), the controller 110 determines whether the relative angle θ is within a predetermined range (-α to +α) (step S40). If the relative angle θ is not within the predetermined range (NO in step S40), the controller 110 proceeds to step S60, which will be described later. If the relative angle θ is within the predetermined range (YES in step S40), the controller 110 opens the switching valve 36 to switch to the permissive state (step S50), and returns to step S10. At this time, water falls from the outlet 32 ​​of the drain pipe 30, and the fallen water is poured into the lower tank 80. As a result, the amount Q of water stored in the upper tank 34 decreases.

[0085] In step S60, the controller 110 determines whether the storage volume Q of the wastewater in the upper tank 34 is equal to or greater than a predetermined storage volume threshold γ (step S70). If the storage volume Q of the upper tank 34 is less than the storage volume threshold γ (NO in step S70), the controller 110 returns to step S10. If the storage volume Q of the upper tank 34 is equal to or greater than the storage volume threshold γ (YES in step S70), the controller 110 rotates the upper rotating body 2 until the relative angle θ falls within a predetermined range (step S80), and then returns to step S10. Alternatively, the controller 110 notifies the operator to rotate the upper rotating body 2 until the relative angle θ falls within the predetermined range (step S80), and then returns to step S10. As a result, the relative angle θ falls within the predetermined range, and the switching valve 36 is switched to the permissive state, whereby the water stored in the upper tank 34 is discharged and poured into the lower tank 80.

[0086] [Second embodiment] Next, a second embodiment relating to the treatment of wastewater discharged from the outlet 32 ​​of the drain pipe 30 will be described. FIG. 9 is a cross-sectional view of the construction machine 10 cut along a plane passing through the rotation axis Z, and is a schematic diagram showing the structure for guiding wastewater discharged from the fuel cell device 42 to the lower tank 150. Comparing FIG. 9 with the schematic diagram of FIG. 6 described above, the structure of the lower tank 150 is different, but other structures and control aspects are basically the same as those of the first embodiment described above. The structure of the lower tank 150 will be described below. The lower tank 150 is an example of a storage unit of the present disclosure.

[0087] 9, the lower tank 150 is disposed directly below the outlet 32 ​​so as to receive the wastewater discharged from the outlet 32 ​​of the drain pipe 30. That is, when the distance between the pivot axis Z and the outlet 32 ​​is defined as a radius R1, and the distance between the pivot axis Z and the center of the lower tank 150 is defined as a radius R2, the lower tank 150 is disposed at a position where the radius R1 is equal to or approximately equal to the radius R2. Furthermore, the lower tank 150 is not particularly limited to a specific shape, such as a cylindrical shape or a rectangular parallelepiped shape, as long as it has an opening 152 at its top.

[0088] The lower tank 150 includes a bottom plate portion 150a held by the upper body 82a, a side wall portion 150b extending upward from the edge of the bottom plate portion 150a, and a handle portion 150c attached to the side wall portion 150b.

[0089] Furthermore, the lower tank 150 is detachably attached to the car body 82 (i.e., the lower running body 1). This allows an operator to grasp the handle 150c and remove the lower tank 150 from the car body 82. As a result, when water accumulates in the lower tank 150, the operator can remove the lower tank 150, move it to a location where water can be drained, and discard the water accumulated in the lower tank 150.

[0090] [Variations] In the above-described embodiments, the openings 78, 152 formed in the lower tanks 80, 150 are circular when viewed vertically from above, but the present disclosure is not limited thereto. For example, the openings may be oval, square, rectangular, or polygonal with pentagons or more sides. Furthermore, the openings may be arc-shaped openings 160 as shown in FIG. 10 . When the openings 160 are arc-shaped, it becomes possible to expand the predetermined range of the relative angle θ within which the lower tank can receive water dropping from the discharge port 32.

[0091] In the above embodiment, after determining whether the turning angular velocity ω is equal to or less than the velocity threshold value β in step S30 of the flowchart in FIG. 8, it is determined whether the relative angle θ is within a predetermined range (-α to +α) in step S40. However, the present disclosure is not limited to this. That is, the order of steps S30 and S40 may be reversed. That is, it may be determined whether the relative angle θ is within a predetermined range, and then it may be determined whether the turning angular velocity ω is equal to or less than the predetermined velocity threshold value β. Similarly, the order of step S10 for detecting the relative angle θ and step S20 for detecting the turning angular velocity ω may be reversed.

[0092] In the above embodiment, control is performed to determine whether the swing angular velocity ω is equal to or less than the velocity threshold value β, but this control may be omitted or performed. That is, the controller 110 switches the switching valve 36 to the permitting state only on the condition that the relative angle θ of the upper swing structure 2 with respect to the lower traveling structure 1 is within a predetermined range (-α to +α).

[0093] In the second embodiment, the lower tank 150 is detachably attached to the lower traveling body 1, but the lower tank 80 in the first embodiment may also be detachably attached to the lower traveling body 1.

[0094] In the above embodiment, a drain cock 92 is provided for draining water stored in the lower tank 80, but the present disclosure is not limited to this as long as the structure is capable of draining water stored in the lower tank 80. For example, the lower tank 80 may be provided with a removable plug, and the water stored in the lower tank 80 may be drained by removing the plug.

[0095] In the above embodiment, the radius R1, which is the distance between the pivot axis Z and the discharge port 32, is equal to or approximately equal to the radius R2, which is the distance between the pivot axis Z and the center of the lower tank 80. However, the present disclosure is not limited to this. That is, the radius R1 and the radius R2 may be different. Specifically, there may be a dimensional difference between the radius R1 and the radius R2 as long as the discharge port 32 can enter the area SA of the opening 78.

[0096] In the above embodiment, the condition for switching the switching valve 36 to the allowable state was whether the relative angle θ, which is the angle at which the center of the outlet 32 ​​and the center of the lower tank 80 coincide, is within a predetermined range (-α to +α). However, even if the outlet 32 ​​does not overlap with the opening 78 in the vertical direction, the predetermined range (-α to +α) based on the relative angle θ may be set based on the water-receiving position, as long as the lower tank 80 is provided with a guide structure capable of guiding water discharged from the outlet 32 ​​and the guide structure is in a position where it can guide the discharged water. By providing the guide structure, it is possible to improve the design freedom for the arrangement of the outlet 32 ​​and the lower tank 80 and the range of the relative angle that can be taken as the allowable state. [Explanation of symbols]

[0097] 1: Lower running body 2: Upper rotating body 10: Construction machinery 30: Drain pipe 32: Outlet (exit of drainage pipe) 34: Upper tank (second storage section) 36: Switching valve 42:Fuel cell device 43:Drain port 78:Aperture 80: Lower tank (storage section) 92: Drain cock (drain plug) 110: Controller 112: Rotation angle sensor (sensor that detects rotation angular velocity) 116: Storage volume sensor (sensor that detects the amount of stored water) 150: Lower tank (storage section) 152:Aperture 160:Aperture

Claims

1. a lower running body; an upper rotating body rotatably supported relative to the lower traveling body; a fuel cell device mounted on the upper rotating body; a drain pipe connected to an apparatus drain outlet formed in the fuel cell apparatus; a reservoir disposed on the lower traveling body and configured to receive water discharged from the outlet of the drain pipe; a switching valve that switches between an allowable state that allows drainage from the drain pipe and a blocked state that blocks drainage from the drain pipe; a controller for controlling the switching valve, the controller switches the switching valve to the permitting state when a relative angle of the upper rotating body with respect to the lower traveling body is within a predetermined range; The predetermined range is an angle range within which the water discharged from the outlet of the drain pipe can be received by the storage section.

2. a sensor for detecting a rotation angular velocity of the upper rotating body; The construction machine according to claim 1 , wherein the controller switches to the permissive state when the relative angle is within the predetermined range and the swing angular velocity is equal to or less than a predetermined velocity threshold.

3. 3. The construction machine according to claim 1, wherein the drain pipe is provided with a second reservoir portion on its path that is capable of temporarily storing water flowing through the drain pipe.

4. a sensor for detecting the amount of water stored in the second storage section; 4. The construction machine according to claim 3, wherein when the storage amount becomes equal to or greater than a predetermined storage amount threshold, the controller rotates the upper rotating body until the relative angle falls within the predetermined range, or notifies the operator to rotate the upper rotating body until the relative angle falls within the predetermined range.

5. 3. The construction machine according to claim 1, wherein the reservoir is provided with an openable and closable drain plug for discharging the water stored in the reservoir to the outside of the reservoir.

6. The construction machine according to claim 1 or 2, wherein the storage section is detachable from the lower traveling body.

7. The storage section has an opening at an upper portion, 3. The construction machine according to claim 1, wherein the opening is positioned vertically below the outlet of the drainage pipe when the relative angle is within the predetermined range.

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